Primary change is HDFFV-11212 - new refs and JNI (#372)

* OESS-98 convert plugin option to FetchContent, add tests

* Fixes for pkcfg files because of plugin option

* OESS-98 fix tools test for plugins

* Keep doxygen comments under 100 chars long - format hint

* Whitespace

* HDFFV-11144 - Reclassify CMake messages

* HDFFV-11099/11100 added help text

* Reworked switch statement to compare string instead

* Fix typo

* Update CDash mode

* Correct name of threadsafe

* Correct option name

* Undo accidental commit

* Note LLVM 10 to 11 format default changes

* Update format plugin

* Undo clang-format version 11 changes

* One more correction

* Update supported platforms

* Revert whitespace changes

* Correct whitespace

* Changes from PR#3

* HDFFV-11213 added option to control gcc10 warnings diagnostics

* HDFFV-11212 Use the new references correctly in JNI utility and tests

* format source

* Fix typo

* Add new test file

* HDFFV-11212 - update test and remove unused arg

* Minor non-space formatting changes

* Use H5I_INVALID_ID instead of "-1"

* source formatting

* add missing testfile, update jni function

* Undo commit of debug code

* remove mislocated file

* Fix h5repack test for handling of fapls and id close

* Update h5diff test files usage text

* HDFFV-11212 add new ref tests for JNI export dataset

* src format update

* Remove blank line typo

* src format typo

* long double requires %Lg

* Another long double foramt specifer S.B. %Lg

* issue with t128bit test

* Windows issue with h5dump and type.

* Fix review issues

* refactor function nesting and fix error checks

* format fixes

* Remove untested functions and javadoc quiet comments

* Restore TRY block.

* Change string append errors to memory exception

* revert to H5_JNI_FATAL_ERROR - support functions need work

* Add assertion error for h5util functions

* remove duplicate function

* format fix

* Revert HD function error handling

* Update copyright comments

51 files changed, 350 insertions, 350 deletions

diff --git a/java/examples/datasets/H5Ex_D_Alloc.java b/java/examples/datasets/H5Ex_D_Alloc.java
index dd7e7ae..e4fcde2 100644
--- a/java/examples/datasets/H5Ex_D_Alloc.java
+++ b/java/examples/datasets/H5Ex_D_Alloc.java
@@ -65,11 +65,11 @@ public class H5Ex_D_Alloc {
     }
 
     private static void allocation() {
-        long file_id = -1;
-        long filespace_id = -1;
-        long dataset_id1 = -1;
-        long dataset_id2 = -1;
-        long dcpl_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long filespace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id1 = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id2 = HDF5Constants.H5I_INVALID_HID;
+        long dcpl_id = HDF5Constants.H5I_INVALID_HID;
         long[] dims = { DIM_X, DIM_Y };
         int[][] dset_data = new int[DIM_X][DIM_Y];
         int space_status = 0;
diff --git a/java/examples/datasets/H5Ex_D_Checksum.java b/java/examples/datasets/H5Ex_D_Checksum.java
index 9dcfdb3..2298791 100644
--- a/java/examples/datasets/H5Ex_D_Checksum.java
+++ b/java/examples/datasets/H5Ex_D_Checksum.java
@@ -93,10 +93,10 @@ public class H5Ex_D_Checksum {
     }
 
     private static void writeChecksum() {
-        long file_id = -1;
-        long filespace_id = -1;
-        long dataset_id = -1;
-        long dcpl_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long filespace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
+        long dcpl_id = HDF5Constants.H5I_INVALID_HID;
         long[] dims = { DIM_X, DIM_Y };
         long[] chunk_dims = { CHUNK_X, CHUNK_Y };
         int[][] dset_data = new int[DIM_X][DIM_Y];
@@ -193,9 +193,9 @@ public class H5Ex_D_Checksum {
     }
 
     private static void readChecksum() {
-        long file_id = -1;
-        long dataset_id = -1;
-        long dcpl_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
+        long dcpl_id = HDF5Constants.H5I_INVALID_HID;
         int[][] dset_data = new int[DIM_X][DIM_Y];
 
         // Open an existing file.
diff --git a/java/examples/datasets/H5Ex_D_Chunk.java b/java/examples/datasets/H5Ex_D_Chunk.java
index 3afa53c..fdbc47d 100644
--- a/java/examples/datasets/H5Ex_D_Chunk.java
+++ b/java/examples/datasets/H5Ex_D_Chunk.java
@@ -66,10 +66,10 @@ public class H5Ex_D_Chunk {
     }
 
     private static void writeChunk() {
-        long file_id = -1;
-        long filespace_id = -1;
-        long dataset_id = -1;
-        long dcpl_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long filespace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
+        long dcpl_id = HDF5Constants.H5I_INVALID_HID;
         long[] dims = { DIM_X, DIM_Y };
         long[] chunk_dims = { CHUNK_X, CHUNK_Y };
         int[][] dset_data = new int[DIM_X][DIM_Y];
@@ -201,10 +201,10 @@ public class H5Ex_D_Chunk {
     }
 
     private static void readChunk() {
-        long file_id = -1;
-        long filespace_id = -1;
-        long dataset_id = -1;
-        long dcpl_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long filespace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
+        long dcpl_id = HDF5Constants.H5I_INVALID_HID;
         int[][] dset_data = new int[DIM_X][DIM_Y];
 
         // Open an existing file.
diff --git a/java/examples/datasets/H5Ex_D_Compact.java b/java/examples/datasets/H5Ex_D_Compact.java
index 347c05c..509b221 100644
--- a/java/examples/datasets/H5Ex_D_Compact.java
+++ b/java/examples/datasets/H5Ex_D_Compact.java
@@ -60,10 +60,10 @@ public class H5Ex_D_Compact {
     }
 
     private static void writeCompact() {
-        long file_id = -1;
-        long filespace_id = -1;
-        long dataset_id = -1;
-        long dcpl_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long filespace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
+        long dcpl_id = HDF5Constants.H5I_INVALID_HID;
         long[] dims = { DIM_X, DIM_Y };
         int[][] dset_data = new int[DIM_X][DIM_Y];
 
@@ -163,10 +163,10 @@ public class H5Ex_D_Compact {
     }
 
     private static void readCompact() {
-        long file_id = -1;
-        long filespace_id = -1;
-        long dataset_id = -1;
-        long dcpl_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long filespace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
+        long dcpl_id = HDF5Constants.H5I_INVALID_HID;
         int[][] dset_data = new int[DIM_X][DIM_Y];
 
         // Open file and dataset using the default properties.
diff --git a/java/examples/datasets/H5Ex_D_External.java b/java/examples/datasets/H5Ex_D_External.java
index 5cf03af..c88234c 100644
--- a/java/examples/datasets/H5Ex_D_External.java
+++ b/java/examples/datasets/H5Ex_D_External.java
@@ -34,10 +34,10 @@ public class H5Ex_D_External {
     private static final int NAME_BUF_SIZE = 32;
 
     private static void writeExternal() {
-        long file_id = -1;
-        long dcpl_id = -1;
-        long filespace_id = -1;
-        long dataset_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long dcpl_id = HDF5Constants.H5I_INVALID_HID;
+        long filespace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
         long[] dims = { DIM_X, DIM_Y };
         int[][] dset_data = new int[DIM_X][DIM_Y];
 
@@ -138,9 +138,9 @@ public class H5Ex_D_External {
     }
 
     private static void readExternal() {
-        long file_id = -1;
-        long dcpl_id = -1;
-        long dataset_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long dcpl_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
         int[][] dset_data = new int[DIM_X][DIM_Y];
         String[] Xname = new String[1];
 
diff --git a/java/examples/datasets/H5Ex_D_FillValue.java b/java/examples/datasets/H5Ex_D_FillValue.java
index a19c026..c8b905e 100644
--- a/java/examples/datasets/H5Ex_D_FillValue.java
+++ b/java/examples/datasets/H5Ex_D_FillValue.java
@@ -40,10 +40,10 @@ public class H5Ex_D_FillValue {
     private static final int FILLVAL = 99;
 
     private static void fillValue() {
-        long file_id = -1;
-        long dcpl_id = -1;
-        long dataspace_id = -1;
-        long dataset_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long dcpl_id = HDF5Constants.H5I_INVALID_HID;
+        long dataspace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
         long[] dims = { DIM_X, DIM_Y };
         long[] extdims = { EDIM_X, EDIM_Y };
         long[] chunk_dims = { CHUNK_X, CHUNK_Y };
diff --git a/java/examples/datasets/H5Ex_D_Gzip.java b/java/examples/datasets/H5Ex_D_Gzip.java
index 67d15bb..cbe6be9 100644
--- a/java/examples/datasets/H5Ex_D_Gzip.java
+++ b/java/examples/datasets/H5Ex_D_Gzip.java
@@ -95,10 +95,10 @@ public class H5Ex_D_Gzip {
     }
 
     private static void writeGzip() {
-        long file_id = -1;
-        long filespace_id = -1;
-        long dataset_id = -1;
-        long dcpl_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long filespace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
+        long dcpl_id = HDF5Constants.H5I_INVALID_HID;
         long[] dims = { DIM_X, DIM_Y };
         long[] chunk_dims = { CHUNK_X, CHUNK_Y };
         int[][] dset_data = new int[DIM_X][DIM_Y];
@@ -196,9 +196,9 @@ public class H5Ex_D_Gzip {
     }
 
     private static void readGzip() {
-        long file_id = -1;
-        long dataset_id = -1;
-        long dcpl_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
+        long dcpl_id = HDF5Constants.H5I_INVALID_HID;
         int[][] dset_data = new int[DIM_X][DIM_Y];
 
         // Open an existing file.
diff --git a/java/examples/datasets/H5Ex_D_Hyperslab.java b/java/examples/datasets/H5Ex_D_Hyperslab.java
index 57dfa6a..6174478 100644
--- a/java/examples/datasets/H5Ex_D_Hyperslab.java
+++ b/java/examples/datasets/H5Ex_D_Hyperslab.java
@@ -34,9 +34,9 @@ public class H5Ex_D_Hyperslab {
     private static final int RANK = 2;
 
     private static void writeHyperslab() {
-        long file_id = -1;
-        long filespace_id = -1;
-        long dataset_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long filespace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
         long[] dims = { DIM_X, DIM_Y };
         int[][] dset_data = new int[DIM_X][DIM_Y];
 
@@ -142,10 +142,10 @@ public class H5Ex_D_Hyperslab {
     }
 
     private static void readHyperslab() {
-        long file_id = -1;
-        long filespace_id = -1;
-        long dataset_id = -1;
-        long dcpl_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long filespace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
+        long dcpl_id = HDF5Constants.H5I_INVALID_HID;
         int[][] dset_data = new int[DIM_X][DIM_Y];
 
         // Open an existing file.
diff --git a/java/examples/datasets/H5Ex_D_Nbit.java b/java/examples/datasets/H5Ex_D_Nbit.java
index d995a02..417d88b 100644
--- a/java/examples/datasets/H5Ex_D_Nbit.java
+++ b/java/examples/datasets/H5Ex_D_Nbit.java
@@ -96,11 +96,11 @@ public class H5Ex_D_Nbit {
     }
 
     private static void writeData() throws Exception {
-        long file_id = -1;
-        long filespace_id = -1;
-        long dataset_id = -1;
-        long dtype_id = -1;
-        long dcpl_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long filespace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
+        long dtype_id = HDF5Constants.H5I_INVALID_HID;
+        long dcpl_id = HDF5Constants.H5I_INVALID_HID;
         long[] dims = { DIM_X, DIM_Y };
         long[] chunk_dims = { CHUNK_X, CHUNK_Y };
         int[][] dset_data = new int[DIM_X][DIM_Y];
@@ -157,9 +157,9 @@ public class H5Ex_D_Nbit {
     }
 
     private static void readData() throws Exception {
-        long file_id = -1;
-        long dataset_id = -1;
-        long dcpl_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
+        long dcpl_id = HDF5Constants.H5I_INVALID_HID;
         int[][] dset_data = new int[DIM_X][DIM_Y];
 
         // Open an existing file.
diff --git a/java/examples/datasets/H5Ex_D_ReadWrite.java b/java/examples/datasets/H5Ex_D_ReadWrite.java
index 3f6e9ac..cf33057 100644
--- a/java/examples/datasets/H5Ex_D_ReadWrite.java
+++ b/java/examples/datasets/H5Ex_D_ReadWrite.java
@@ -32,9 +32,9 @@ public class H5Ex_D_ReadWrite {
     private static final int RANK = 2;
 
     private static void WriteDataset() {
-        long file_id = -1;
-        long filespace_id = -1;
-        long dataset_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long filespace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
         long[] dims = { DIM_X, DIM_Y };
         int[][] dset_data = new int[DIM_X][DIM_Y];
 
@@ -109,8 +109,8 @@ public class H5Ex_D_ReadWrite {
     }
 
     private static void ReadDataset() {
-        long file_id = -1;
-        long dataset_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
         int[][] dset_data = new int[DIM_X][DIM_Y];
 
         // Open file using the default properties.
diff --git a/java/examples/datasets/H5Ex_D_Shuffle.java b/java/examples/datasets/H5Ex_D_Shuffle.java
index 9677e75..9e705bd 100644
--- a/java/examples/datasets/H5Ex_D_Shuffle.java
+++ b/java/examples/datasets/H5Ex_D_Shuffle.java
@@ -122,10 +122,10 @@ public class H5Ex_D_Shuffle {
     }
 
     private static void writeShuffle() {
-        long file_id = -1;
-        long filespace_id = -1;
-        long dataset_id = -1;
-        long dcpl_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long filespace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
+        long dcpl_id = HDF5Constants.H5I_INVALID_HID;
         long[] dims = { DIM_X, DIM_Y };
         long[] chunk_dims = { CHUNK_X, CHUNK_Y };
         int[][] dset_data = new int[DIM_X][DIM_Y];
@@ -229,9 +229,9 @@ public class H5Ex_D_Shuffle {
     }
 
     private static void readShuffle() {
-        long file_id = -1;
-        long dataset_id = -1;
-        long dcpl_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
+        long dcpl_id = HDF5Constants.H5I_INVALID_HID;
         int[][] dset_data = new int[DIM_X][DIM_Y];
 
         // Open an existing file.
diff --git a/java/examples/datasets/H5Ex_D_Sofloat.java b/java/examples/datasets/H5Ex_D_Sofloat.java
index 5818371..22ee2d3 100644
--- a/java/examples/datasets/H5Ex_D_Sofloat.java
+++ b/java/examples/datasets/H5Ex_D_Sofloat.java
@@ -96,10 +96,10 @@ public class H5Ex_D_Sofloat {
     }
 
     private static void writeData() {
-        long file_id = -1;
-        long filespace_id = -1;
-        long dataset_id = -1;
-        long dcpl_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long filespace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
+        long dcpl_id = HDF5Constants.H5I_INVALID_HID;
         long[] dims = { DIM_X, DIM_Y };
         long[] chunk_dims = { CHUNK_X, CHUNK_Y };
         double[][] dset_data = new double[DIM_X][DIM_Y];
@@ -213,9 +213,9 @@ public class H5Ex_D_Sofloat {
     }
 
     private static void readData() {
-        long file_id = -1;
-        long dataset_id = -1;
-        long dcpl_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
+        long dcpl_id = HDF5Constants.H5I_INVALID_HID;
         double[][] dset_data = new double[DIM_X][DIM_Y];
 
         // Open file using the default properties.
diff --git a/java/examples/datasets/H5Ex_D_Soint.java b/java/examples/datasets/H5Ex_D_Soint.java
index 3f5f170..b2f0a29 100644
--- a/java/examples/datasets/H5Ex_D_Soint.java
+++ b/java/examples/datasets/H5Ex_D_Soint.java
@@ -96,10 +96,10 @@ public class H5Ex_D_Soint {
     }
 
     private static void writeData() {
-        long file_id = -1;
-        long filespace_id = -1;
-        long dataset_id = -1;
-        long dcpl_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long filespace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
+        long dcpl_id = HDF5Constants.H5I_INVALID_HID;
         long[] dims = { DIM_X, DIM_Y };
         long[] chunk_dims = { CHUNK_X, CHUNK_Y };
         int[][] dset_data = new int[DIM_X][DIM_Y];
@@ -195,9 +195,9 @@ public class H5Ex_D_Soint {
     }
 
     private static void readData() {
-        long file_id = -1;
-        long dataset_id = -1;
-        long dcpl_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
+        long dcpl_id = HDF5Constants.H5I_INVALID_HID;
         int[][] dset_data = new int[DIM_X][DIM_Y];
 
         // Open file using the default properties.
diff --git a/java/examples/datasets/H5Ex_D_Szip.java b/java/examples/datasets/H5Ex_D_Szip.java
index 57ba873..8891bc9 100644
--- a/java/examples/datasets/H5Ex_D_Szip.java
+++ b/java/examples/datasets/H5Ex_D_Szip.java
@@ -95,10 +95,10 @@ public class H5Ex_D_Szip {
     }
 
     private static void writeSzip() {
-        long file_id = -1;
-        long filespace_id = -1;
-        long dataset_id = -1;
-        long dcpl_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long filespace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
+        long dcpl_id = HDF5Constants.H5I_INVALID_HID;
         long[] dims = { DIM_X, DIM_Y };
         long[] chunk_dims = { CHUNK_X, CHUNK_Y };
         int[][] dset_data = new int[DIM_X][DIM_Y];
@@ -196,9 +196,9 @@ public class H5Ex_D_Szip {
     }
 
     private static void readSzip() {
-        long file_id = -1;
-        long dataset_id = -1;
-        long dcpl_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
+        long dcpl_id = HDF5Constants.H5I_INVALID_HID;
         int[][] dset_data = new int[DIM_X][DIM_Y];
 
         // Open an existing file.
diff --git a/java/examples/datasets/H5Ex_D_Transform.java b/java/examples/datasets/H5Ex_D_Transform.java
index 04bfa2e..7f0cf5a 100644
--- a/java/examples/datasets/H5Ex_D_Transform.java
+++ b/java/examples/datasets/H5Ex_D_Transform.java
@@ -36,10 +36,10 @@ public class H5Ex_D_Transform {
     private static String RTRANSFORM = "x-1";
 
     private static void writeData() {
-        long file_id = -1;
-        long filespace_id = -1;
-        long dataset_id = -1;
-        long dxpl_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long filespace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
+        long dxpl_id = HDF5Constants.H5I_INVALID_HID;
 
         long[] dims = { DIM_X, DIM_Y };
         int[][] dset_data = new int[DIM_X][DIM_Y];
@@ -144,9 +144,9 @@ public class H5Ex_D_Transform {
 
     private static void readData() {
 
-        long file_id = -1;
-        long dataset_id = -1;
-        long dxpl_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
+        long dxpl_id = HDF5Constants.H5I_INVALID_HID;
         int[][] dset_data = new int[DIM_X][DIM_Y];
 
         // Open an existing file using the default properties.
diff --git a/java/examples/datasets/H5Ex_D_UnlimitedAdd.java b/java/examples/datasets/H5Ex_D_UnlimitedAdd.java
index 925023a..deecd7c 100644
--- a/java/examples/datasets/H5Ex_D_UnlimitedAdd.java
+++ b/java/examples/datasets/H5Ex_D_UnlimitedAdd.java
@@ -39,10 +39,10 @@ public class H5Ex_D_UnlimitedAdd {
     private static final int NDIMS = 2;
 
     private static void writeUnlimited() {
-        long file_id = -1;
-        long dcpl_id = -1;
-        long dataspace_id = -1;
-        long dataset_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long dcpl_id = HDF5Constants.H5I_INVALID_HID;
+        long dataspace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
         long[] dims = { DIM_X, DIM_Y };
         long[] chunk_dims = { CHUNK_X, CHUNK_Y };
         long[] maxdims = { HDF5Constants.H5S_UNLIMITED, HDF5Constants.H5S_UNLIMITED };
@@ -143,9 +143,9 @@ public class H5Ex_D_UnlimitedAdd {
     }
 
     private static void extendUnlimited() {
-        long file_id = -1;
-        long dataspace_id = -1;
-        long dataset_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long dataspace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
         long[] dims = { DIM_X, DIM_Y };
         long[] extdims = { EDIM_X, EDIM_Y };
         long[] start = { 0, 0 };
@@ -293,9 +293,9 @@ public class H5Ex_D_UnlimitedAdd {
     }
 
     private static void readUnlimited() {
-        long file_id = -1;
-        long dataspace_id = -1;
-        long dataset_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long dataspace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
         long[] dims = { DIM_X, DIM_Y };
         int[][] dset_data;
 
diff --git a/java/examples/datasets/H5Ex_D_UnlimitedGzip.java b/java/examples/datasets/H5Ex_D_UnlimitedGzip.java
index 40ddc60..2421610 100644
--- a/java/examples/datasets/H5Ex_D_UnlimitedGzip.java
+++ b/java/examples/datasets/H5Ex_D_UnlimitedGzip.java
@@ -99,10 +99,10 @@ public class H5Ex_D_UnlimitedGzip {
     }
 
     private static void writeUnlimited() {
-        long file_id = -1;
-        long dcpl_id = -1;
-        long dataspace_id = -1;
-        long dataset_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long dcpl_id = HDF5Constants.H5I_INVALID_HID;
+        long dataspace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
         long[] dims = { DIM_X, DIM_Y };
         long[] chunk_dims = { CHUNK_X, CHUNK_Y };
         long[] maxdims = { HDF5Constants.H5S_UNLIMITED, HDF5Constants.H5S_UNLIMITED };
@@ -200,9 +200,9 @@ public class H5Ex_D_UnlimitedGzip {
     }
 
     private static void extendUnlimited() {
-        long file_id = -1;
-        long dataspace_id = -1;
-        long dataset_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long dataspace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
         long[] dims = { DIM_X, DIM_Y };
         long[] extdims = { EDIM_X, EDIM_Y };
         long[] start = { 0, 0 };
@@ -350,10 +350,10 @@ public class H5Ex_D_UnlimitedGzip {
     }
 
     private static void readUnlimited() {
-        long file_id = -1;
-        long dataspace_id = -1;
-        long dataset_id = -1;
-        long dcpl_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long dataspace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
+        long dcpl_id = HDF5Constants.H5I_INVALID_HID;
         long[] dims = { DIM_X, DIM_Y };
         int[][] dset_data;
 
diff --git a/java/examples/datasets/H5Ex_D_UnlimitedMod.java b/java/examples/datasets/H5Ex_D_UnlimitedMod.java
index 0476bc1..966ab03 100644
--- a/java/examples/datasets/H5Ex_D_UnlimitedMod.java
+++ b/java/examples/datasets/H5Ex_D_UnlimitedMod.java
@@ -39,10 +39,10 @@ public class H5Ex_D_UnlimitedMod {
     private static final int NDIMS = 2;
 
     private static void writeUnlimited() {
-        long file_id = -1;
-        long dcpl_id = -1;
-        long dataspace_id = -1;
-        long dataset_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long dcpl_id = HDF5Constants.H5I_INVALID_HID;
+        long dataspace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
         long[] dims = { DIM_X, DIM_Y };
         long[] chunk_dims = { CHUNK_X, CHUNK_Y };
         long[] maxdims = { HDF5Constants.H5S_UNLIMITED, HDF5Constants.H5S_UNLIMITED };
@@ -143,9 +143,9 @@ public class H5Ex_D_UnlimitedMod {
     }
 
     private static void extendUnlimited() {
-        long file_id = -1;
-        long dataspace_id = -1;
-        long dataset_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long dataspace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
         long[] dims = { DIM_X, DIM_Y };
         long[] extdims = { EDIM_X, EDIM_Y };
         int[][] dset_data;
@@ -279,9 +279,9 @@ public class H5Ex_D_UnlimitedMod {
     }
 
     private static void readUnlimited() {
-        long file_id = -1;
-        long dataspace_id = -1;
-        long dataset_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long dataspace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
         long[] dims = { DIM_X, DIM_Y };
         int[][] dset_data;
 
diff --git a/java/examples/datatypes/H5Ex_T_Array.java b/java/examples/datatypes/H5Ex_T_Array.java
index 30eb360..7b8a4bd 100644
--- a/java/examples/datatypes/H5Ex_T_Array.java
+++ b/java/examples/datatypes/H5Ex_T_Array.java
@@ -34,11 +34,11 @@ public class H5Ex_T_Array {
     private static final int NDIMS = 2;
 
     private static void CreateDataset() {
-        long file_id = -1;
-        long filetype_id = -1;
-        long memtype_id = -1;
-        long dataspace_id = -1;
-        long dataset_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long filetype_id = HDF5Constants.H5I_INVALID_HID;
+        long memtype_id = HDF5Constants.H5I_INVALID_HID;
+        long dataspace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
         long[] dims = { DIM0 };
         long[] adims = { ADIM0, ADIM1 };
         int[][][] dset_data = new int[DIM0][ADIM0][ADIM1];
@@ -152,10 +152,10 @@ public class H5Ex_T_Array {
     }
 
     private static void ReadDataset() {
-        long file_id = -1;
-        long filetype_id = -1;
-        long memtype_id = -1;
-        long dataset_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long filetype_id = HDF5Constants.H5I_INVALID_HID;
+        long memtype_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
         long[] dims = { DIM0 };
         long[] adims = { ADIM0, ADIM1 };
         int[][][] dset_data;
diff --git a/java/examples/datatypes/H5Ex_T_ArrayAttribute.java b/java/examples/datatypes/H5Ex_T_ArrayAttribute.java
index 26d7fb6..cd6b174 100644
--- a/java/examples/datatypes/H5Ex_T_ArrayAttribute.java
+++ b/java/examples/datatypes/H5Ex_T_ArrayAttribute.java
@@ -35,12 +35,12 @@ public class H5Ex_T_ArrayAttribute {
     private static final int NDIMS = 2;
 
     private static void CreateDataset() {
-        long file_id = -1;
-        long filetype_id = -1;
-        long memtype_id = -1;
-        long dataspace_id = -1;
-        long dataset_id = -1;
-        long attribute_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long filetype_id = HDF5Constants.H5I_INVALID_HID;
+        long memtype_id = HDF5Constants.H5I_INVALID_HID;
+        long dataspace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
+        long attribute_id = HDF5Constants.H5I_INVALID_HID;
         long[] dims = { DIM0 };
         long[] adims = { ADIM0, ADIM1 };
         int[][][] dset_data = new int[DIM0][ADIM0][ADIM1];
@@ -84,7 +84,7 @@ public class H5Ex_T_ArrayAttribute {
                 dataset_id = H5.H5Dcreate(file_id, DATASETNAME, HDF5Constants.H5T_STD_I32LE, dataspace_id,
                         HDF5Constants.H5P_DEFAULT, HDF5Constants.H5P_DEFAULT, HDF5Constants.H5P_DEFAULT);
                 H5.H5Sclose(dataspace_id);
-                dataspace_id = -1;
+                dataspace_id = HDF5Constants.H5I_INVALID_HID;
             }
         }
         catch (Exception e) {
@@ -175,11 +175,11 @@ public class H5Ex_T_ArrayAttribute {
     }
 
     private static void ReadDataset() {
-        long file_id = -1;
-        long filetype_id = -1;
-        long memtype_id = -1;
-        long dataset_id = -1;
-        long attribute_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long filetype_id = HDF5Constants.H5I_INVALID_HID;
+        long memtype_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
+        long attribute_id = HDF5Constants.H5I_INVALID_HID;
         long[] dims = { DIM0 };
         long[] adims = { ADIM0, ADIM1 };
         int[][][] dset_data;
diff --git a/java/examples/datatypes/H5Ex_T_Bit.java b/java/examples/datatypes/H5Ex_T_Bit.java
index 30acda4..d14f850 100644
--- a/java/examples/datatypes/H5Ex_T_Bit.java
+++ b/java/examples/datatypes/H5Ex_T_Bit.java
@@ -32,9 +32,9 @@ public class H5Ex_T_Bit {
     private static final int RANK = 2;
 
     private static void CreateDataset() {
-        long file_id = -1;
-        long dataspace_id = -1;
-        long dataset_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long dataspace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
         long[] dims = { DIM0, DIM1 };
         int[][] dset_data = new int[DIM0][DIM1];
 
@@ -116,9 +116,9 @@ public class H5Ex_T_Bit {
     }
 
     private static void ReadDataset() {
-        long file_id = -1;
-        long dataspace_id = -1;
-        long dataset_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long dataspace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
         long[] dims = { DIM0, DIM1 };
         int[][] dset_data;
 
diff --git a/java/examples/datatypes/H5Ex_T_BitAttribute.java b/java/examples/datatypes/H5Ex_T_BitAttribute.java
index 2059dd5..eae9624 100644
--- a/java/examples/datatypes/H5Ex_T_BitAttribute.java
+++ b/java/examples/datatypes/H5Ex_T_BitAttribute.java
@@ -33,10 +33,10 @@ public class H5Ex_T_BitAttribute {
     private static final int RANK = 2;
 
     private static void CreateDataset() {
-        long file_id = -1;
-        long dataspace_id = -1;
-        long dataset_id = -1;
-        long attribute_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long dataspace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
+        long attribute_id = HDF5Constants.H5I_INVALID_HID;
         long[] dims = { DIM0, DIM1 };
         int[][] dset_data = new int[DIM0][DIM1];
 
@@ -66,7 +66,7 @@ public class H5Ex_T_BitAttribute {
                 dataset_id = H5.H5Dcreate(file_id, DATASETNAME, HDF5Constants.H5T_STD_I32LE, dataspace_id,
                         HDF5Constants.H5P_DEFAULT, HDF5Constants.H5P_DEFAULT, HDF5Constants.H5P_DEFAULT);
                 H5.H5Sclose(dataspace_id);
-                dataspace_id = -1;
+                dataspace_id = HDF5Constants.H5I_INVALID_HID;
             }
         }
         catch (Exception e) {
@@ -139,10 +139,10 @@ public class H5Ex_T_BitAttribute {
     }
 
     private static void ReadDataset() {
-        long file_id = -1;
-        long dataspace_id = -1;
-        long dataset_id = -1;
-        long attribute_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long dataspace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
+        long attribute_id = HDF5Constants.H5I_INVALID_HID;
         long[] dims = { DIM0, DIM1 };
         int[][] dset_data;
 
diff --git a/java/examples/datatypes/H5Ex_T_Commit.java b/java/examples/datatypes/H5Ex_T_Commit.java
index 35caa6b..fe72d58 100644
--- a/java/examples/datatypes/H5Ex_T_Commit.java
+++ b/java/examples/datatypes/H5Ex_T_Commit.java
@@ -101,9 +101,9 @@ public class H5Ex_T_Commit {
     }
 
     private static void CreateDataType() {
-        long file_id = -1;
-        long strtype_id = -1;
-        long filetype_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long strtype_id = HDF5Constants.H5I_INVALID_HID;
+        long filetype_id = HDF5Constants.H5I_INVALID_HID;
         Sensor_Datatype datatypes = new Sensor_Datatype();
         // Create a new file using default properties.
         try {
@@ -183,9 +183,9 @@ public class H5Ex_T_Commit {
     }
 
     private static void ReadDataType() {
-        long file_id = -1;
-        long typeclass_id = -1;
-        long filetype_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long typeclass_id = HDF5Constants.H5I_INVALID_HID;
+        long filetype_id = HDF5Constants.H5I_INVALID_HID;
 
         // Open an existing file.
         try {
diff --git a/java/examples/datatypes/H5Ex_T_Compound.java b/java/examples/datatypes/H5Ex_T_Compound.java
index 61e79c7..b5b30b1 100644
--- a/java/examples/datatypes/H5Ex_T_Compound.java
+++ b/java/examples/datatypes/H5Ex_T_Compound.java
@@ -122,12 +122,12 @@ public class H5Ex_T_Compound {
     }
 
     private static void CreateDataset() {
-        long file_id = -1;
-        long strtype_id = -1;
-        long memtype_id = -1;
-        long filetype_id = -1;
-        long dataspace_id = -1;
-        long dataset_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long strtype_id = HDF5Constants.H5I_INVALID_HID;
+        long memtype_id = HDF5Constants.H5I_INVALID_HID;
+        long filetype_id = HDF5Constants.H5I_INVALID_HID;
+        long dataspace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
         long[] dims = { DIM0 };
         Sensor[] object_data = new Sensor[DIM0];
         byte[] dset_data = null;
@@ -286,11 +286,11 @@ public class H5Ex_T_Compound {
     }
 
     private static void ReadDataset() {
-        long file_id = -1;
-        long strtype_id = -1;
-        long memtype_id = -1;
-        long dataspace_id = -1;
-        long dataset_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long strtype_id = HDF5Constants.H5I_INVALID_HID;
+        long memtype_id = HDF5Constants.H5I_INVALID_HID;
+        long dataspace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
         long[] dims = { DIM0 };
         Sensor[] object_data2;
         byte[] dset_data;
diff --git a/java/examples/datatypes/H5Ex_T_CompoundAttribute.java b/java/examples/datatypes/H5Ex_T_CompoundAttribute.java
index 4294b4a..678472f 100644
--- a/java/examples/datatypes/H5Ex_T_CompoundAttribute.java
+++ b/java/examples/datatypes/H5Ex_T_CompoundAttribute.java
@@ -125,13 +125,13 @@ public class H5Ex_T_CompoundAttribute {
     }
 
     private static void CreateDataset() {
-        long file_id = -1;
-        long strtype_id = -1;
-        long memtype_id = -1;
-        long filetype_id = -1;
-        long dataspace_id = -1;
-        long dataset_id = -1;
-        long attribute_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long strtype_id = HDF5Constants.H5I_INVALID_HID;
+        long memtype_id = HDF5Constants.H5I_INVALID_HID;
+        long filetype_id = HDF5Constants.H5I_INVALID_HID;
+        long dataspace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
+        long attribute_id = HDF5Constants.H5I_INVALID_HID;
         long[] dims = { DIM0 };
         Sensor[] object_data = new Sensor[DIM0];
         byte[] dset_data = null;
@@ -205,7 +205,7 @@ public class H5Ex_T_CompoundAttribute {
                 dataset_id = H5.H5Dcreate(file_id, DATASETNAME, HDF5Constants.H5T_STD_I32LE, dataspace_id,
                         HDF5Constants.H5P_DEFAULT, HDF5Constants.H5P_DEFAULT, HDF5Constants.H5P_DEFAULT);
                 H5.H5Sclose(dataspace_id);
-                dataspace_id = -1;
+                dataspace_id = HDF5Constants.H5I_INVALID_HID;
             }
         }
         catch (Exception e) {
@@ -310,12 +310,12 @@ public class H5Ex_T_CompoundAttribute {
     }
 
     private static void ReadDataset() {
-        long file_id = -1;
-        long strtype_id = -1;
-        long memtype_id = -1;
-        long dataspace_id = -1;
-        long dataset_id = -1;
-        long attribute_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long strtype_id = HDF5Constants.H5I_INVALID_HID;
+        long memtype_id = HDF5Constants.H5I_INVALID_HID;
+        long dataspace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
+        long attribute_id = HDF5Constants.H5I_INVALID_HID;
         long[] dims = { DIM0 };
         Sensor[] object_data2;
         byte[] dset_data;
diff --git a/java/examples/datatypes/H5Ex_T_Float.java b/java/examples/datatypes/H5Ex_T_Float.java
index e469d63..f808954 100644
--- a/java/examples/datatypes/H5Ex_T_Float.java
+++ b/java/examples/datatypes/H5Ex_T_Float.java
@@ -36,9 +36,9 @@ public class H5Ex_T_Float {
     private static final int RANK = 2;
 
     private static void CreateDataset() {
-        long file_id = -1;
-        long dataspace_id = -1;
-        long dataset_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long dataspace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
         long[] dims = { DIM0, DIM1 };
         double[][] dset_data = new double[DIM0][DIM1];
 
@@ -120,9 +120,9 @@ public class H5Ex_T_Float {
     }
 
     private static void ReadDataset() {
-        long file_id = -1;
-        long dataspace_id = -1;
-        long dataset_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long dataspace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
         long[] dims = { DIM0, DIM1 };
         double[][] dset_data;
 
diff --git a/java/examples/datatypes/H5Ex_T_FloatAttribute.java b/java/examples/datatypes/H5Ex_T_FloatAttribute.java
index b6c92be..2f98b5a 100644
--- a/java/examples/datatypes/H5Ex_T_FloatAttribute.java
+++ b/java/examples/datatypes/H5Ex_T_FloatAttribute.java
@@ -37,10 +37,10 @@ public class H5Ex_T_FloatAttribute {
     private static final int RANK = 2;
 
     private static void CreateDataset() {
-        long file_id = -1;
-        long dataspace_id = -1;
-        long dataset_id = -1;
-        long attribute_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long dataspace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
+        long attribute_id = HDF5Constants.H5I_INVALID_HID;
         long[] dims = { DIM0, DIM1 };
         double[][] dset_data = new double[DIM0][DIM1];
 
@@ -66,7 +66,7 @@ public class H5Ex_T_FloatAttribute {
                 dataset_id = H5.H5Dcreate(file_id, DATASETNAME, HDF5Constants.H5T_STD_I32LE, dataspace_id,
                         HDF5Constants.H5P_DEFAULT, HDF5Constants.H5P_DEFAULT, HDF5Constants.H5P_DEFAULT);
                 H5.H5Sclose(dataspace_id);
-                dataspace_id = -1;
+                dataspace_id = HDF5Constants.H5I_INVALID_HID;
             }
         }
         catch (Exception e) {
@@ -139,10 +139,10 @@ public class H5Ex_T_FloatAttribute {
     }
 
     private static void ReadDataset() {
-        long file_id = -1;
-        long dataspace_id = -1;
-        long dataset_id = -1;
-        long attribute_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long dataspace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
+        long attribute_id = HDF5Constants.H5I_INVALID_HID;
         long[] dims = { DIM0, DIM1 };
         double[][] dset_data;
 
diff --git a/java/examples/datatypes/H5Ex_T_Integer.java b/java/examples/datatypes/H5Ex_T_Integer.java
index f0b3755..e99cdb6 100644
--- a/java/examples/datatypes/H5Ex_T_Integer.java
+++ b/java/examples/datatypes/H5Ex_T_Integer.java
@@ -34,9 +34,9 @@ public class H5Ex_T_Integer {
     private static final int RANK = 2;
 
     private static void CreateDataset() {
-        long file_id = -1;
-        long dataspace_id = -1;
-        long dataset_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long dataspace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
         long[] dims = { DIM0, DIM1 };
         int[][] dset_data = new int[DIM0][DIM1];
 
@@ -117,9 +117,9 @@ public class H5Ex_T_Integer {
     }
 
     private static void ReadDataset() {
-        long file_id = -1;
-        long dataspace_id = -1;
-        long dataset_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long dataspace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
         long[] dims = { DIM0, DIM1 };
         int[][] dset_data;
 
diff --git a/java/examples/datatypes/H5Ex_T_IntegerAttribute.java b/java/examples/datatypes/H5Ex_T_IntegerAttribute.java
index 8c85c63..b80b342 100644
--- a/java/examples/datatypes/H5Ex_T_IntegerAttribute.java
+++ b/java/examples/datatypes/H5Ex_T_IntegerAttribute.java
@@ -35,10 +35,10 @@ public class H5Ex_T_IntegerAttribute {
     private static final int RANK = 2;
 
     private static void CreateDataset() {
-        long file_id = -1;
-        long dataspace_id = -1;
-        long dataset_id = -1;
-        long attribute_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long dataspace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
+        long attribute_id = HDF5Constants.H5I_INVALID_HID;
         long[] dims = { DIM0, DIM1 };
         int[][] dset_data = new int[DIM0][DIM1];
 
@@ -64,7 +64,7 @@ public class H5Ex_T_IntegerAttribute {
                 dataset_id = H5.H5Dcreate(file_id, DATASETNAME, HDF5Constants.H5T_STD_I32LE, dataspace_id,
                         HDF5Constants.H5P_DEFAULT, HDF5Constants.H5P_DEFAULT, HDF5Constants.H5P_DEFAULT);
                 H5.H5Sclose(dataspace_id);
-                dataspace_id = -1;
+                dataspace_id = HDF5Constants.H5I_INVALID_HID;
             }
         }
         catch (Exception e) {
@@ -137,10 +137,10 @@ public class H5Ex_T_IntegerAttribute {
     }
 
     private static void ReadDataset() {
-        long file_id = -1;
-        long dataspace_id = -1;
-        long dataset_id = -1;
-        long attribute_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long dataspace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
+        long attribute_id = HDF5Constants.H5I_INVALID_HID;
         long[] dims = { DIM0, DIM1 };
         int[][] dset_data;
 
diff --git a/java/examples/datatypes/H5Ex_T_ObjectReference.java b/java/examples/datatypes/H5Ex_T_ObjectReference.java
index 97f02af..0099bfa 100644
--- a/java/examples/datatypes/H5Ex_T_ObjectReference.java
+++ b/java/examples/datatypes/H5Ex_T_ObjectReference.java
@@ -65,11 +65,11 @@ public class H5Ex_T_ObjectReference {
     }
 
     private static void writeObjRef() {
-        long file_id = -1;
-        long dataspace_id = -1;
-        long filespace_id = -1;
-        long group_id = -1;
-        long dataset_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long dataspace_id = HDF5Constants.H5I_INVALID_HID;
+        long filespace_id = HDF5Constants.H5I_INVALID_HID;
+        long group_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
         long[] dims = { DIM0 };
         byte[][] dset_data = new byte[DIM0][8];
 
@@ -90,9 +90,9 @@ public class H5Ex_T_ObjectReference {
                         HDF5Constants.H5P_DEFAULT, HDF5Constants.H5P_DEFAULT, HDF5Constants.H5P_DEFAULT);
                 if (dataset_id >= 0)
                     H5.H5Dclose(dataset_id);
-                dataset_id = -1;
+                dataset_id = HDF5Constants.H5I_INVALID_HID;
                 H5.H5Sclose(dataspace_id);
-                dataspace_id = -1;
+                dataspace_id = HDF5Constants.H5I_INVALID_HID;
             }
         }
         catch (Exception e) {
@@ -106,7 +106,7 @@ public class H5Ex_T_ObjectReference {
                         HDF5Constants.H5P_DEFAULT);
             if (group_id >= 0)
                 H5.H5Gclose(group_id);
-            group_id = -1;
+            group_id = HDF5Constants.H5I_INVALID_HID;
         }
         catch (Exception e) {
             e.printStackTrace();
@@ -187,11 +187,11 @@ public class H5Ex_T_ObjectReference {
     }
 
     private static void readObjRef() {
-        long file_id = -1;
-        long dataset_id = -1;
-        long dataspace_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
+        long dataspace_id = HDF5Constants.H5I_INVALID_HID;
         int object_type = -1;
-        long object_id = -1;
+        long object_id = HDF5Constants.H5I_INVALID_HID;
         long[] dims = { DIM0 };
         byte[][] dset_data;
 
diff --git a/java/examples/datatypes/H5Ex_T_ObjectReferenceAttribute.java b/java/examples/datatypes/H5Ex_T_ObjectReferenceAttribute.java
index b1cab7c..ee2fe26 100644
--- a/java/examples/datatypes/H5Ex_T_ObjectReferenceAttribute.java
+++ b/java/examples/datatypes/H5Ex_T_ObjectReferenceAttribute.java
@@ -67,11 +67,11 @@ public class H5Ex_T_ObjectReferenceAttribute {
     }
 
     private static void CreateDataset() {
-        long file_id = -1;
-        long dataspace_id = -1;
-        long group_id = -1;
-        long dataset_id = -1;
-        long attribute_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long dataspace_id = HDF5Constants.H5I_INVALID_HID;
+        long group_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
+        long attribute_id = HDF5Constants.H5I_INVALID_HID;
         long[] dims = { DIM0 };
         byte[][] dset_data = new byte[DIM0][8];
 
@@ -92,9 +92,9 @@ public class H5Ex_T_ObjectReferenceAttribute {
                         HDF5Constants.H5P_DEFAULT, HDF5Constants.H5P_DEFAULT, HDF5Constants.H5P_DEFAULT);
                 if (dataset_id >= 0)
                     H5.H5Dclose(dataset_id);
-                dataset_id = -1;
+                dataset_id = HDF5Constants.H5I_INVALID_HID;
                 H5.H5Sclose(dataspace_id);
-                dataspace_id = -1;
+                dataspace_id = HDF5Constants.H5I_INVALID_HID;
             }
         }
         catch (Exception e) {
@@ -108,7 +108,7 @@ public class H5Ex_T_ObjectReferenceAttribute {
                         HDF5Constants.H5P_DEFAULT);
             if (group_id >= 0)
                 H5.H5Gclose(group_id);
-            group_id = -1;
+            group_id = HDF5Constants.H5I_INVALID_HID;
         }
         catch (Exception e) {
             e.printStackTrace();
@@ -139,7 +139,7 @@ public class H5Ex_T_ObjectReferenceAttribute {
                 dataset_id = H5.H5Dcreate(file_id, DATASETNAME, HDF5Constants.H5T_STD_I32LE, dataspace_id,
                         HDF5Constants.H5P_DEFAULT, HDF5Constants.H5P_DEFAULT, HDF5Constants.H5P_DEFAULT);
                 H5.H5Sclose(dataspace_id);
-                dataspace_id = -1;
+                dataspace_id = HDF5Constants.H5I_INVALID_HID;
             }
         }
         catch (Exception e) {
@@ -212,12 +212,12 @@ public class H5Ex_T_ObjectReferenceAttribute {
     }
 
     private static void ReadDataset() {
-        long file_id = -1;
-        long dataspace_id = -1;
-        long dataset_id = -1;
-        long attribute_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long dataspace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
+        long attribute_id = HDF5Constants.H5I_INVALID_HID;
         int object_type = -1;
-        long object_id = -1;
+        long object_id = HDF5Constants.H5I_INVALID_HID;
         long[] dims = { DIM0 };
         byte[][] dset_data;
 
diff --git a/java/examples/datatypes/H5Ex_T_Opaque.java b/java/examples/datatypes/H5Ex_T_Opaque.java
index 1d9ab1b..09ecbe6 100644
--- a/java/examples/datatypes/H5Ex_T_Opaque.java
+++ b/java/examples/datatypes/H5Ex_T_Opaque.java
@@ -32,10 +32,10 @@ public class H5Ex_T_Opaque {
     private static final int RANK = 1;
 
     private static void CreateDataset() {
-        long file_id = -1;
-        long dataspace_id = -1;
-        long datatype_id = -1;
-        long dataset_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long dataspace_id = HDF5Constants.H5I_INVALID_HID;
+        long datatype_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
         long[] dims = { DIM0 };
         byte[] dset_data = new byte[DIM0 * LEN];
         byte[] str_data = { 'O', 'P', 'A', 'Q', 'U', 'E' };
@@ -138,11 +138,11 @@ public class H5Ex_T_Opaque {
     }
 
     private static void ReadDataset() {
-        long file_id = -1;
-        long datatype_id = -1;
-        long dataspace_id = -1;
-        long dataset_id = -1;
-        long type_len = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long datatype_id = HDF5Constants.H5I_INVALID_HID;
+        long dataspace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
+        long type_len = HDF5Constants.H5I_INVALID_HID;
         long[] dims = { DIM0 };
         byte[] dset_data;
         String tag_name = null;
diff --git a/java/examples/datatypes/H5Ex_T_OpaqueAttribute.java b/java/examples/datatypes/H5Ex_T_OpaqueAttribute.java
index 8955d77..abfa810 100644
--- a/java/examples/datatypes/H5Ex_T_OpaqueAttribute.java
+++ b/java/examples/datatypes/H5Ex_T_OpaqueAttribute.java
@@ -33,11 +33,11 @@ public class H5Ex_T_OpaqueAttribute {
     private static final int RANK = 1;
 
     private static void CreateDataset() {
-        long file_id = -1;
-        long dataspace_id = -1;
-        long datatype_id = -1;
-        long dataset_id = -1;
-        long attribute_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long dataspace_id = HDF5Constants.H5I_INVALID_HID;
+        long datatype_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
+        long attribute_id = HDF5Constants.H5I_INVALID_HID;
         long[] dims = { DIM0 };
         byte[] dset_data = new byte[DIM0 * LEN];
         byte[] str_data = { 'O', 'P', 'A', 'Q', 'U', 'E' };
@@ -65,7 +65,7 @@ public class H5Ex_T_OpaqueAttribute {
                 dataset_id = H5.H5Dcreate(file_id, DATASETNAME, HDF5Constants.H5T_STD_I32LE, dataspace_id,
                         HDF5Constants.H5P_DEFAULT, HDF5Constants.H5P_DEFAULT, HDF5Constants.H5P_DEFAULT);
                 H5.H5Sclose(dataspace_id);
-                dataspace_id = -1;
+                dataspace_id = HDF5Constants.H5I_INVALID_HID;
             }
         }
         catch (Exception e) {
@@ -158,11 +158,11 @@ public class H5Ex_T_OpaqueAttribute {
     }
 
     private static void ReadDataset() {
-        long file_id = -1;
-        long datatype_id = -1;
-        long dataspace_id = -1;
-        long dataset_id = -1;
-        long attribute_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long datatype_id = HDF5Constants.H5I_INVALID_HID;
+        long dataspace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
+        long attribute_id = HDF5Constants.H5I_INVALID_HID;
         long type_len = -1;
         long[] dims = { DIM0 };
         byte[] dset_data;
diff --git a/java/examples/datatypes/H5Ex_T_String.java b/java/examples/datatypes/H5Ex_T_String.java
index f91d866..107c52b 100644
--- a/java/examples/datatypes/H5Ex_T_String.java
+++ b/java/examples/datatypes/H5Ex_T_String.java
@@ -32,11 +32,11 @@ public class H5Ex_T_String {
     private static final int RANK = 1;
 
     private static void CreateDataset() {
-        long file_id = -1;
-        long memtype_id = -1;
-        long filetype_id = -1;
-        long dataspace_id = -1;
-        long dataset_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long memtype_id = HDF5Constants.H5I_INVALID_HID;
+        long filetype_id = HDF5Constants.H5I_INVALID_HID;
+        long dataspace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
         long[] dims = { DIM0 };
         byte[][] dset_data = new byte[DIM0][SDIM];
         StringBuffer[] str_data = { new StringBuffer("Parting"), new StringBuffer("is such"),
@@ -156,11 +156,11 @@ public class H5Ex_T_String {
     }
 
     private static void ReadDataset() {
-        long file_id = -1;
-        long filetype_id = -1;
-        long memtype_id = -1;
-        long dataspace_id = -1;
-        long dataset_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long filetype_id = HDF5Constants.H5I_INVALID_HID;
+        long memtype_id = HDF5Constants.H5I_INVALID_HID;
+        long dataspace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
         long sdim = 0;
         long[] dims = { DIM0 };
         byte[][] dset_data;
diff --git a/java/examples/datatypes/H5Ex_T_StringAttribute.java b/java/examples/datatypes/H5Ex_T_StringAttribute.java
index 7fe46c8..ab5e95c 100644
--- a/java/examples/datatypes/H5Ex_T_StringAttribute.java
+++ b/java/examples/datatypes/H5Ex_T_StringAttribute.java
@@ -33,12 +33,12 @@ public class H5Ex_T_StringAttribute {
     private static final int RANK = 1;
 
     private static void CreateDataset() {
-        long file_id = -1;
-        long memtype_id = -1;
-        long filetype_id = -1;
-        long dataspace_id = -1;
-        long dataset_id = -1;
-        long attribute_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long memtype_id = HDF5Constants.H5I_INVALID_HID;
+        long filetype_id = HDF5Constants.H5I_INVALID_HID;
+        long dataspace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
+        long attribute_id = HDF5Constants.H5I_INVALID_HID;
         long[] dims = { DIM0 };
         byte[][] dset_data = new byte[DIM0][SDIM];
         StringBuffer[] str_data = { new StringBuffer("Parting"), new StringBuffer("is such"),
@@ -80,7 +80,7 @@ public class H5Ex_T_StringAttribute {
                 dataset_id = H5.H5Dcreate(file_id, DATASETNAME, HDF5Constants.H5T_STD_I32LE, dataspace_id,
                         HDF5Constants.H5P_DEFAULT, HDF5Constants.H5P_DEFAULT, HDF5Constants.H5P_DEFAULT);
                 H5.H5Sclose(dataspace_id);
-                dataspace_id = -1;
+                dataspace_id = HDF5Constants.H5I_INVALID_HID;
             }
         }
         catch (Exception e) {
@@ -179,12 +179,12 @@ public class H5Ex_T_StringAttribute {
     }
 
     private static void ReadDataset() {
-        long file_id = -1;
-        long filetype_id = -1;
-        long memtype_id = -1;
-        long dataspace_id = -1;
-        long dataset_id = -1;
-        long attribute_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long filetype_id = HDF5Constants.H5I_INVALID_HID;
+        long memtype_id = HDF5Constants.H5I_INVALID_HID;
+        long dataspace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
+        long attribute_id = HDF5Constants.H5I_INVALID_HID;
         long sdim = 0;
         long[] dims = { DIM0 };
         byte[][] dset_data;
diff --git a/java/examples/datatypes/H5Ex_T_VLString.java b/java/examples/datatypes/H5Ex_T_VLString.java
index e1c9bd5..4a638eb 100644
--- a/java/examples/datatypes/H5Ex_T_VLString.java
+++ b/java/examples/datatypes/H5Ex_T_VLString.java
@@ -26,10 +26,10 @@ public class H5Ex_T_VLString
     private static String DATASETNAME = "DS1";
 
     private static void createDataset() {
-        long file_id = -1;
-        long type_id = -1;
-        long dataspace_id = -1;
-        long dataset_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long type_id = HDF5Constants.H5I_INVALID_HID;
+        long dataspace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
         int rank = 1;
         String[] str_data = { "Parting", "is such", "sweet", "sorrow." };
         long[] dims = { str_data.length };
@@ -93,9 +93,9 @@ public class H5Ex_T_VLString
     }
 
     private static void readDataset() {
-        long file_id = -1;
-        long type_id = -1;
-        long dataset_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long type_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
         String[] str_data = { "", "", "", "" };
 
         try {
diff --git a/java/examples/groups/H5Ex_G_Compact.java b/java/examples/groups/H5Ex_G_Compact.java
index 6078c6c..a24ed33 100644
--- a/java/examples/groups/H5Ex_G_Compact.java
+++ b/java/examples/groups/H5Ex_G_Compact.java
@@ -60,9 +60,9 @@ public class H5Ex_G_Compact {
     }
 
     public static void CreateGroup() {
-        long file_id = -1;
-        long group_id = -1;
-        long fapl_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long group_id = HDF5Constants.H5I_INVALID_HID;
+        long fapl_id = HDF5Constants.H5I_INVALID_HID;
         H5G_info_t ginfo;
         long size;
 
diff --git a/java/examples/groups/H5Ex_G_Corder.java b/java/examples/groups/H5Ex_G_Corder.java
index 74f70ba..a00252f 100644
--- a/java/examples/groups/H5Ex_G_Corder.java
+++ b/java/examples/groups/H5Ex_G_Corder.java
@@ -25,10 +25,10 @@ public class H5Ex_G_Corder {
     private static String FILE = "H5Ex_G_Corder.h5";
 
     private static void CreateGroup() throws Exception {
-        long file_id = -1;
-        long group_id = -1;
-        long subgroup_id = -1;
-        long gcpl_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long group_id = HDF5Constants.H5I_INVALID_HID;
+        long subgroup_id = HDF5Constants.H5I_INVALID_HID;
+        long gcpl_id = HDF5Constants.H5I_INVALID_HID;
         int status;
         H5G_info_t ginfo;
         int i;
diff --git a/java/examples/groups/H5Ex_G_Create.java b/java/examples/groups/H5Ex_G_Create.java
index f653987..7d9e150 100644
--- a/java/examples/groups/H5Ex_G_Create.java
+++ b/java/examples/groups/H5Ex_G_Create.java
@@ -25,8 +25,8 @@ public class H5Ex_G_Create {
     private static String GROUPNAME = "G1";
 
     private static void CreateGroup() {
-        long file_id = -1;
-        long group_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long group_id = HDF5Constants.H5I_INVALID_HID;
 
         // Create a new file using default properties.
         try {
diff --git a/java/examples/groups/H5Ex_G_Intermediate.java b/java/examples/groups/H5Ex_G_Intermediate.java
index 6109e9a..4649741 100644
--- a/java/examples/groups/H5Ex_G_Intermediate.java
+++ b/java/examples/groups/H5Ex_G_Intermediate.java
@@ -31,9 +31,9 @@ public class H5Ex_G_Intermediate {
 
     private void CreateGroup() throws Exception {
 
-        long file_id = -1;
-        long group_id = -1;
-        long gcpl_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long group_id = HDF5Constants.H5I_INVALID_HID;
+        long gcpl_id = HDF5Constants.H5I_INVALID_HID;
 
         try {
             // Create a new file_id using the default properties.
diff --git a/java/examples/groups/H5Ex_G_Iterate.java b/java/examples/groups/H5Ex_G_Iterate.java
index 71361f8..02798eb 100644
--- a/java/examples/groups/H5Ex_G_Iterate.java
+++ b/java/examples/groups/H5Ex_G_Iterate.java
@@ -58,7 +58,7 @@ public class H5Ex_G_Iterate {
     }
 
     private static void do_iterate() {
-        long file_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
 
         // Open a file using default properties.
         try {
diff --git a/java/examples/groups/H5Ex_G_Phase.java b/java/examples/groups/H5Ex_G_Phase.java
index 7824123..744ce6c 100644
--- a/java/examples/groups/H5Ex_G_Phase.java
+++ b/java/examples/groups/H5Ex_G_Phase.java
@@ -60,11 +60,11 @@ public class H5Ex_G_Phase {
     }
 
     private static void CreateGroup() {
-        long file_id = -1;
-        long group_id = -1;
-        long subgroup_id = -1;
-        long fapl_id = -1;
-        long gcpl_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long group_id = HDF5Constants.H5I_INVALID_HID;
+        long subgroup_id = HDF5Constants.H5I_INVALID_HID;
+        long fapl_id = HDF5Constants.H5I_INVALID_HID;
+        long gcpl_id = HDF5Constants.H5I_INVALID_HID;
         H5G_info_t ginfo;
         String name = "G0"; // Name of subgroup_id
         int i;
diff --git a/java/examples/groups/H5Ex_G_Traverse.java b/java/examples/groups/H5Ex_G_Traverse.java
index 76ed6c8..61f2122 100644
--- a/java/examples/groups/H5Ex_G_Traverse.java
+++ b/java/examples/groups/H5Ex_G_Traverse.java
@@ -43,7 +43,7 @@ public class H5Ex_G_Traverse {
     public static H5L_iterate_t iter_cb = new H5L_iter_callbackT();
 
     private static void OpenGroup() {
-        long file_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
         H5O_info_t infobuf;
         opdata od = new opdata();
 
diff --git a/java/examples/groups/H5Ex_G_Visit.java b/java/examples/groups/H5Ex_G_Visit.java
index c479259..544cbf4 100644
--- a/java/examples/groups/H5Ex_G_Visit.java
+++ b/java/examples/groups/H5Ex_G_Visit.java
@@ -47,7 +47,7 @@ public class H5Ex_G_Visit {
 
     private void VisitGroup() throws Exception {
 
-        long file_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
 
         try {
             // Open file
diff --git a/java/examples/intro/H5_CreateAttribute.java b/java/examples/intro/H5_CreateAttribute.java
index 22b03ad..ab45039 100644
--- a/java/examples/intro/H5_CreateAttribute.java
+++ b/java/examples/intro/H5_CreateAttribute.java
@@ -28,10 +28,10 @@ public class H5_CreateAttribute {
     private static String DATASETATTRIBUTE = "Units";
 
     private static void CreateDatasetAttribute() {
-        long file_id = -1;
-        long dataspace_id = -1;
-        long dataset_id = -1;
-        long attribute_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long dataspace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
+        long attribute_id = HDF5Constants.H5I_INVALID_HID;
         long[] dims1 = { DIM_X, DIM_Y };
         long[] dims = { 2 };
         int[] attr_data = { 100, 200 };
diff --git a/java/examples/intro/H5_CreateDataset.java b/java/examples/intro/H5_CreateDataset.java
index 7b56e83..f376272 100644
--- a/java/examples/intro/H5_CreateDataset.java
+++ b/java/examples/intro/H5_CreateDataset.java
@@ -27,9 +27,9 @@ public class H5_CreateDataset {
     private static final int DIM_Y = 6;
 
     private static void CreateDataset() {
-        long file_id = -1;
-        long dataspace_id = -1;
-        long dataset_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long dataspace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
         long[] dims = { DIM_X, DIM_Y };
 
         // Create a new file using default properties.
diff --git a/java/examples/intro/H5_CreateFile.java b/java/examples/intro/H5_CreateFile.java
index 367e61f..773df81 100644
--- a/java/examples/intro/H5_CreateFile.java
+++ b/java/examples/intro/H5_CreateFile.java
@@ -24,7 +24,7 @@ public class H5_CreateFile {
     static final String FILENAME = "H5_CreateFile.h5";
 
     private static void CreateFile() {
-        long file_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
 
         // Create a new file using default properties.
         try {
diff --git a/java/examples/intro/H5_CreateGroup.java b/java/examples/intro/H5_CreateGroup.java
index 54f6252..ab970e1 100644
--- a/java/examples/intro/H5_CreateGroup.java
+++ b/java/examples/intro/H5_CreateGroup.java
@@ -25,8 +25,8 @@ public class H5_CreateGroup {
     private static String GROUPNAME = "MyGroup";
 
     private static void CreateGroup() {
-        long file_id = -1;
-        long group_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long group_id = HDF5Constants.H5I_INVALID_HID;
 
         // Create a new file using default properties.
         try {
diff --git a/java/examples/intro/H5_CreateGroupAbsoluteRelative.java b/java/examples/intro/H5_CreateGroupAbsoluteRelative.java
index b9c35d7..ae142ae 100644
--- a/java/examples/intro/H5_CreateGroupAbsoluteRelative.java
+++ b/java/examples/intro/H5_CreateGroupAbsoluteRelative.java
@@ -27,10 +27,10 @@ public class H5_CreateGroupAbsoluteRelative {
     private static String GROUPNAME_B = "GroupB";
 
     private static void CreateGroupAbsoluteAndRelative() {
-        long file_id = -1;
-        long group1_id = -1;
-        long group2_id = -1;
-        long group3_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long group1_id = HDF5Constants.H5I_INVALID_HID;
+        long group2_id = HDF5Constants.H5I_INVALID_HID;
+        long group3_id = HDF5Constants.H5I_INVALID_HID;
 
         // Create a new file using default properties.
         try {
diff --git a/java/examples/intro/H5_CreateGroupDataset.java b/java/examples/intro/H5_CreateGroupDataset.java
index 191a21a..9657cf0 100644
--- a/java/examples/intro/H5_CreateGroupDataset.java
+++ b/java/examples/intro/H5_CreateGroupDataset.java
@@ -32,12 +32,12 @@ public class H5_CreateGroupDataset {
     private static final int DIM2_Y = 10;
 
     private static void h5_crtgrpd() {
-        long file_id = -1;
-        long dataspace_id = -1;
-        long dataset_id = -1;
-        long group_id = -1;
-        long group1_id = -1;
-        long group2_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long dataspace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
+        long group_id = HDF5Constants.H5I_INVALID_HID;
+        long group1_id = HDF5Constants.H5I_INVALID_HID;
+        long group2_id = HDF5Constants.H5I_INVALID_HID;
         int[][] dset1_data = new int[DIM1_X][DIM1_Y];
         int[][] dset2_data = new int[DIM2_X][DIM2_Y];
         long[] dims1 = { DIM1_X, DIM1_Y };
@@ -108,7 +108,7 @@ public class H5_CreateGroupDataset {
         try {
             if (dataspace_id >= 0)
                 H5.H5Sclose(dataspace_id);
-            dataspace_id = -1;
+            dataspace_id = HDF5Constants.H5I_INVALID_HID;
         }
         catch (Exception e) {
             e.printStackTrace();
@@ -118,7 +118,7 @@ public class H5_CreateGroupDataset {
         try {
             if (dataset_id >= 0)
                 H5.H5Dclose(dataset_id);
-            dataset_id = -1;
+            dataset_id = HDF5Constants.H5I_INVALID_HID;
         }
         catch (Exception e) {
             e.printStackTrace();
diff --git a/java/examples/intro/H5_ReadWrite.java b/java/examples/intro/H5_ReadWrite.java
index 812ac77..82beec9 100644
--- a/java/examples/intro/H5_ReadWrite.java
+++ b/java/examples/intro/H5_ReadWrite.java
@@ -27,9 +27,9 @@ public class H5_ReadWrite {
     private static final int DIM_Y = 6;
 
     private static void ReadWriteDataset() {
-        long file_id = -1;
-        long dataspace_id = -1;
-        long dataset_id = -1;
+        long file_id = HDF5Constants.H5I_INVALID_HID;
+        long dataspace_id = HDF5Constants.H5I_INVALID_HID;
+        long dataset_id = HDF5Constants.H5I_INVALID_HID;
         long[] dims = { DIM_X, DIM_Y };
         int[][] dset_data = new int[DIM_X][DIM_Y];