[svn-r30313] HDFFV-9972: unsatisfied link error under debug on Windows.

Added windows name suffix for debug to CMake cmd_arg for examples and test.
Fix issues discovered under debug testing;
   Create a version of H5Iget_name that correctly returns the name.
   Rework PIN_JAVA_STRING macro and usage to eliminate possible memory leaks by using if-else instead of mid-routine return.
   Update example to use new H5Iget_name API.
   
   Tested: windows under debug

1 files changed, 322 insertions, 352 deletions

diff --git a/java/src/jni/h5oImp.c b/java/src/jni/h5oImp.c
index 872bb4c..24f6988 100644
--- a/java/src/jni/h5oImp.c
+++ b/java/src/jni/h5oImp.c
@@ -46,17 +46,18 @@ JNIEXPORT jlong JNICALL
 Java_hdf_hdf5lib_H5__1H5Oopen
     (JNIEnv *env, jclass clss, jlong loc_id, jstring name, jlong access_plist_id)
 {
-    hid_t       status;
+    hid_t       status = -1;
     const char *oName;
 
-    PIN_JAVA_STRING(name, oName, -1);
+    PIN_JAVA_STRING(name, oName);
+    if (oName != NULL) {
+        status = H5Oopen((hid_t)loc_id, oName, (hid_t)access_plist_id );
 
-    status = H5Oopen((hid_t)loc_id, oName, (hid_t)access_plist_id );
-
-    UNPIN_JAVA_STRING(name, oName);
+        UNPIN_JAVA_STRING(name, oName);
 
-    if (status < 0)
-        h5libraryError(env);
+        if (status < 0)
+            h5libraryError(env);
+    }
 
     return (jlong)status;
 } /* end Java_hdf_hdf5lib_H5__1H5Oopen */
@@ -92,14 +93,15 @@ Java_hdf_hdf5lib_H5_H5Ocopy
     const char *lCurName;
     const char *lDstName;
 
-    PIN_JAVA_STRING_TWO0(cur_name, lCurName, dst_name, lDstName);
+    PIN_JAVA_STRING_TWO(cur_name, lCurName, dst_name, lDstName);
+    if (lCurName != NULL && lDstName != NULL) {
+        status = H5Ocopy((hid_t)cur_loc_id, lCurName, (hid_t)dst_loc_id, lDstName, (hid_t)create_id, (hid_t)access_id);
 
-    status = H5Ocopy((hid_t)cur_loc_id, lCurName, (hid_t)dst_loc_id, lDstName, (hid_t)create_id, (hid_t)access_id);
+        UNPIN_JAVA_STRING_TWO(cur_name, lCurName, dst_name, lDstName);
 
-    UNPIN_JAVA_STRING_TWO(cur_name, lCurName, dst_name, lDstName);
-
-    if (status < 0)
-        h5libraryError(env);
+        if (status < 0)
+            h5libraryError(env);
+    }
 } /* end Java_hdf_hdf5lib_H5_H5Ocopy */
 
 /*
@@ -123,44 +125,44 @@ Java_hdf_hdf5lib_H5_H5Oget_1info
 
     if (status < 0) {
         h5libraryError(env);
-        return NULL;
     } /* end if */
-
-    args[0].i = (jint)infobuf.hdr.version;
-    args[1].i = (jint)infobuf.hdr.nmesgs;
-    args[2].i = (jint)infobuf.hdr.nchunks;
-    args[3].i = (jint)infobuf.hdr.flags;
-    args[4].j = (jlong)infobuf.hdr.space.total;
-    args[5].j = (jlong)infobuf.hdr.space.meta;
-    args[6].j = (jlong)infobuf.hdr.space.mesg;
-    args[7].j = (jlong)infobuf.hdr.space.free;
-    args[8].j = (jlong)infobuf.hdr.mesg.present;
-    args[9].j = (jlong)infobuf.hdr.mesg.shared;
-    CALL_CONSTRUCTOR("hdf/hdf5lib/structs/H5O_hdr_info_t", "(IIIIJJJJJJ)V", args);
-    hdrinfobuf = ret_obj;
-
-    args[0].j = (jlong)infobuf.meta_size.obj.index_size;
-    args[1].j = (jlong)infobuf.meta_size.obj.heap_size;
-    CALL_CONSTRUCTOR("hdf/hdf5lib/structs/H5_ih_info_t", "(JJ)V", args);
-    ihinfobuf1 = ret_obj;
-    args[0].j = (jlong)infobuf.meta_size.attr.index_size;
-    args[1].j = (jlong)infobuf.meta_size.attr.heap_size;
-    CALL_CONSTRUCTOR("hdf/hdf5lib/structs/H5_ih_info_t", "(JJ)V", args);
-    ihinfobuf2 = ret_obj;
-
-    args[0].j = (jlong)infobuf.fileno;
-    args[1].j = (jlong)infobuf.addr;
-    args[2].i = infobuf.type;
-    args[3].i = (jint)infobuf.rc;
-    args[4].j = (jlong)infobuf.num_attrs;
-    args[5].j = infobuf.atime;
-    args[6].j = infobuf.mtime;
-    args[7].j = infobuf.ctime;
-    args[8].j = infobuf.btime;
-    args[9].l = hdrinfobuf;
-    args[10].l = ihinfobuf1;
-    args[11].l = ihinfobuf2;
-    CALL_CONSTRUCTOR("hdf/hdf5lib/structs/H5O_info_t", "(JJIIJJJJJLhdf/hdf5lib/structs/H5O_hdr_info_t;Lhdf/hdf5lib/structs/H5_ih_info_t;Lhdf/hdf5lib/structs/H5_ih_info_t;)V", args);
+    else {
+        args[0].i = (jint)infobuf.hdr.version;
+        args[1].i = (jint)infobuf.hdr.nmesgs;
+        args[2].i = (jint)infobuf.hdr.nchunks;
+        args[3].i = (jint)infobuf.hdr.flags;
+        args[4].j = (jlong)infobuf.hdr.space.total;
+        args[5].j = (jlong)infobuf.hdr.space.meta;
+        args[6].j = (jlong)infobuf.hdr.space.mesg;
+        args[7].j = (jlong)infobuf.hdr.space.free;
+        args[8].j = (jlong)infobuf.hdr.mesg.present;
+        args[9].j = (jlong)infobuf.hdr.mesg.shared;
+        CALL_CONSTRUCTOR("hdf/hdf5lib/structs/H5O_hdr_info_t", "(IIIIJJJJJJ)V", args);
+        hdrinfobuf = ret_obj;
+
+        args[0].j = (jlong)infobuf.meta_size.obj.index_size;
+        args[1].j = (jlong)infobuf.meta_size.obj.heap_size;
+        CALL_CONSTRUCTOR("hdf/hdf5lib/structs/H5_ih_info_t", "(JJ)V", args);
+        ihinfobuf1 = ret_obj;
+        args[0].j = (jlong)infobuf.meta_size.attr.index_size;
+        args[1].j = (jlong)infobuf.meta_size.attr.heap_size;
+        CALL_CONSTRUCTOR("hdf/hdf5lib/structs/H5_ih_info_t", "(JJ)V", args);
+        ihinfobuf2 = ret_obj;
+
+        args[0].j = (jlong)infobuf.fileno;
+        args[1].j = (jlong)infobuf.addr;
+        args[2].i = infobuf.type;
+        args[3].i = (jint)infobuf.rc;
+        args[4].j = (jlong)infobuf.num_attrs;
+        args[5].j = infobuf.atime;
+        args[6].j = infobuf.mtime;
+        args[7].j = infobuf.ctime;
+        args[8].j = infobuf.btime;
+        args[9].l = hdrinfobuf;
+        args[10].l = ihinfobuf1;
+        args[11].l = ihinfobuf2;
+        CALL_CONSTRUCTOR("hdf/hdf5lib/structs/H5O_info_t", "(JJIIJJJJJLhdf/hdf5lib/structs/H5O_hdr_info_t;Lhdf/hdf5lib/structs/H5_ih_info_t;Lhdf/hdf5lib/structs/H5_ih_info_t;)V", args);
+    }
 
     return ret_obj;
 } /* end Java_hdf_hdf5lib_H5_H5Oget_1info */
@@ -183,52 +185,53 @@ Java_hdf_hdf5lib_H5_H5Oget_1info_1by_1name
     jobject     ihinfobuf2;
     jobject     ret_obj = NULL;
 
-    PIN_JAVA_STRING(name, lName, NULL);
-
-    status = H5Oget_info_by_name((hid_t)loc_id, lName, &infobuf, (hid_t)access_id);
+    PIN_JAVA_STRING(name, lName);
+    if (lName != NULL) {
+        status = H5Oget_info_by_name((hid_t)loc_id, lName, &infobuf, (hid_t)access_id);
 
-    UNPIN_JAVA_STRING(name, lName);
+        UNPIN_JAVA_STRING(name, lName);
 
-    if (status < 0) {
-        h5libraryError(env);
-        return NULL;
-    } /* end if */
-
-    args[0].i = (jint)infobuf.hdr.version;
-    args[1].i = (jint)infobuf.hdr.nmesgs;
-    args[2].i = (jint)infobuf.hdr.nchunks;
-    args[3].i = (jint)infobuf.hdr.flags;
-    args[4].j = (jlong)infobuf.hdr.space.total;
-    args[5].j = (jlong)infobuf.hdr.space.meta;
-    args[6].j = (jlong)infobuf.hdr.space.mesg;
-    args[7].j = (jlong)infobuf.hdr.space.free;
-    args[8].j = (jlong)infobuf.hdr.mesg.present;
-    args[9].j = (jlong)infobuf.hdr.mesg.shared;
-    CALL_CONSTRUCTOR("hdf/hdf5lib/structs/H5O_hdr_info_t", "(IIIIJJJJJJ)V", args);
-    hdrinfobuf = ret_obj;
-
-    args[0].j = (jlong)infobuf.meta_size.obj.index_size;
-    args[1].j = (jlong)infobuf.meta_size.obj.heap_size;
-    CALL_CONSTRUCTOR("hdf/hdf5lib/structs/H5_ih_info_t", "(JJ)V", args);
-    ihinfobuf1 = ret_obj;
-    args[0].j = (jlong)infobuf.meta_size.attr.index_size;
-    args[1].j = (jlong)infobuf.meta_size.attr.heap_size;
-    CALL_CONSTRUCTOR("hdf/hdf5lib/structs/H5_ih_info_t", "(JJ)V", args);
-    ihinfobuf2 = ret_obj;
-
-    args[0].j = (jlong)infobuf.fileno;
-    args[1].j = (jlong)infobuf.addr;
-    args[2].i = infobuf.type;
-    args[3].i = (jint)infobuf.rc;
-    args[4].j = (jlong)infobuf.num_attrs;
-    args[5].j = infobuf.atime;
-    args[6].j = infobuf.mtime;
-    args[7].j = infobuf.ctime;
-    args[8].j = infobuf.btime;
-    args[9].l = hdrinfobuf;
-    args[10].l = ihinfobuf1;
-    args[11].l = ihinfobuf2;
-    CALL_CONSTRUCTOR("hdf/hdf5lib/structs/H5O_info_t", "(JJIIJJJJJLhdf/hdf5lib/structs/H5O_hdr_info_t;Lhdf/hdf5lib/structs/H5_ih_info_t;Lhdf/hdf5lib/structs/H5_ih_info_t;)V", args);
+        if (status < 0) {
+            h5libraryError(env);
+        } /* end if */
+        else {
+            args[0].i = (jint)infobuf.hdr.version;
+            args[1].i = (jint)infobuf.hdr.nmesgs;
+            args[2].i = (jint)infobuf.hdr.nchunks;
+            args[3].i = (jint)infobuf.hdr.flags;
+            args[4].j = (jlong)infobuf.hdr.space.total;
+            args[5].j = (jlong)infobuf.hdr.space.meta;
+            args[6].j = (jlong)infobuf.hdr.space.mesg;
+            args[7].j = (jlong)infobuf.hdr.space.free;
+            args[8].j = (jlong)infobuf.hdr.mesg.present;
+            args[9].j = (jlong)infobuf.hdr.mesg.shared;
+            CALL_CONSTRUCTOR("hdf/hdf5lib/structs/H5O_hdr_info_t", "(IIIIJJJJJJ)V", args);
+            hdrinfobuf = ret_obj;
+
+            args[0].j = (jlong)infobuf.meta_size.obj.index_size;
+            args[1].j = (jlong)infobuf.meta_size.obj.heap_size;
+            CALL_CONSTRUCTOR("hdf/hdf5lib/structs/H5_ih_info_t", "(JJ)V", args);
+            ihinfobuf1 = ret_obj;
+            args[0].j = (jlong)infobuf.meta_size.attr.index_size;
+            args[1].j = (jlong)infobuf.meta_size.attr.heap_size;
+            CALL_CONSTRUCTOR("hdf/hdf5lib/structs/H5_ih_info_t", "(JJ)V", args);
+            ihinfobuf2 = ret_obj;
+
+            args[0].j = (jlong)infobuf.fileno;
+            args[1].j = (jlong)infobuf.addr;
+            args[2].i = infobuf.type;
+            args[3].i = (jint)infobuf.rc;
+            args[4].j = (jlong)infobuf.num_attrs;
+            args[5].j = infobuf.atime;
+            args[6].j = infobuf.mtime;
+            args[7].j = infobuf.ctime;
+            args[8].j = infobuf.btime;
+            args[9].l = hdrinfobuf;
+            args[10].l = ihinfobuf1;
+            args[11].l = ihinfobuf2;
+            CALL_CONSTRUCTOR("hdf/hdf5lib/structs/H5O_info_t", "(JJIIJJJJJLhdf/hdf5lib/structs/H5O_hdr_info_t;Lhdf/hdf5lib/structs/H5_ih_info_t;Lhdf/hdf5lib/structs/H5_ih_info_t;)V", args);
+        }
+    }
 
     return ret_obj;
 } /* end Java_hdf_hdf5lib_H5_H5Oget_1info_1by_1name */
@@ -252,52 +255,53 @@ Java_hdf_hdf5lib_H5_H5Oget_1info_1by_1idx
     jobject     ihinfobuf2;
     jobject     ret_obj = NULL;
 
-    PIN_JAVA_STRING(name, lName, NULL);
+    PIN_JAVA_STRING(name, lName);
+    if (lName != NULL) {
+        status = H5Oget_info_by_idx((hid_t)loc_id, lName, (H5_index_t)index_field, (H5_iter_order_t)order, (hsize_t)link_n, &infobuf, (hid_t)access_id);
 
-    status = H5Oget_info_by_idx((hid_t)loc_id, lName, (H5_index_t)index_field, (H5_iter_order_t)order, (hsize_t)link_n, &infobuf, (hid_t)access_id);
+        UNPIN_JAVA_STRING(name, lName);
 
-    UNPIN_JAVA_STRING(name, lName);
-
-    if (status < 0) {
-        h5libraryError(env);
-        return NULL;
-    } /* end if */
-
-    args[0].i = (jint)infobuf.hdr.version;
-    args[1].i = (jint)infobuf.hdr.nmesgs;
-    args[2].i = (jint)infobuf.hdr.nchunks;
-    args[3].i = (jint)infobuf.hdr.flags;
-    args[4].j = (jlong)infobuf.hdr.space.total;
-    args[5].j = (jlong)infobuf.hdr.space.meta;
-    args[6].j = (jlong)infobuf.hdr.space.mesg;
-    args[7].j = (jlong)infobuf.hdr.space.free;
-    args[8].j = (jlong)infobuf.hdr.mesg.present;
-    args[9].j = (jlong)infobuf.hdr.mesg.shared;
-    CALL_CONSTRUCTOR("hdf/hdf5lib/structs/H5O_hdr_info_t", "(IIIIJJJJJJ)V", args);
-    hdrinfobuf = ret_obj;
-
-    args[0].j = (jlong)infobuf.meta_size.obj.index_size;
-    args[1].j = (jlong)infobuf.meta_size.obj.heap_size;
-    CALL_CONSTRUCTOR("hdf/hdf5lib/structs/H5_ih_info_t", "(JJ)V", args);
-    ihinfobuf1 = ret_obj;
-    args[0].j = (jlong)infobuf.meta_size.attr.index_size;
-    args[1].j = (jlong)infobuf.meta_size.attr.heap_size;
-    CALL_CONSTRUCTOR("hdf/hdf5lib/structs/H5_ih_info_t", "(JJ)V", args);
-    ihinfobuf2 = ret_obj;
-
-    args[0].j = (jlong)infobuf.fileno;
-    args[1].j = (jlong)infobuf.addr;
-    args[2].i = infobuf.type;
-    args[3].i = (jint)infobuf.rc;
-    args[4].j = (jlong)infobuf.num_attrs;
-    args[5].j = infobuf.atime;
-    args[6].j = infobuf.mtime;
-    args[7].j = infobuf.ctime;
-    args[8].j = infobuf.btime;
-    args[9].l = hdrinfobuf;
-    args[10].l = ihinfobuf1;
-    args[11].l = ihinfobuf2;
-    CALL_CONSTRUCTOR("hdf/hdf5lib/structs/H5O_info_t", "(JJIIJJJJJLhdf/hdf5lib/structs/H5O_hdr_info_t;Lhdf/hdf5lib/structs/H5_ih_info_t;Lhdf/hdf5lib/structs/H5_ih_info_t;)V", args);
+        if (status < 0) {
+            h5libraryError(env);
+        } /* end if */
+        else {
+            args[0].i = (jint)infobuf.hdr.version;
+            args[1].i = (jint)infobuf.hdr.nmesgs;
+            args[2].i = (jint)infobuf.hdr.nchunks;
+            args[3].i = (jint)infobuf.hdr.flags;
+            args[4].j = (jlong)infobuf.hdr.space.total;
+            args[5].j = (jlong)infobuf.hdr.space.meta;
+            args[6].j = (jlong)infobuf.hdr.space.mesg;
+            args[7].j = (jlong)infobuf.hdr.space.free;
+            args[8].j = (jlong)infobuf.hdr.mesg.present;
+            args[9].j = (jlong)infobuf.hdr.mesg.shared;
+            CALL_CONSTRUCTOR("hdf/hdf5lib/structs/H5O_hdr_info_t", "(IIIIJJJJJJ)V", args);
+            hdrinfobuf = ret_obj;
+
+            args[0].j = (jlong)infobuf.meta_size.obj.index_size;
+            args[1].j = (jlong)infobuf.meta_size.obj.heap_size;
+            CALL_CONSTRUCTOR("hdf/hdf5lib/structs/H5_ih_info_t", "(JJ)V", args);
+            ihinfobuf1 = ret_obj;
+            args[0].j = (jlong)infobuf.meta_size.attr.index_size;
+            args[1].j = (jlong)infobuf.meta_size.attr.heap_size;
+            CALL_CONSTRUCTOR("hdf/hdf5lib/structs/H5_ih_info_t", "(JJ)V", args);
+            ihinfobuf2 = ret_obj;
+
+            args[0].j = (jlong)infobuf.fileno;
+            args[1].j = (jlong)infobuf.addr;
+            args[2].i = infobuf.type;
+            args[3].i = (jint)infobuf.rc;
+            args[4].j = (jlong)infobuf.num_attrs;
+            args[5].j = infobuf.atime;
+            args[6].j = infobuf.mtime;
+            args[7].j = infobuf.ctime;
+            args[8].j = infobuf.btime;
+            args[9].l = hdrinfobuf;
+            args[10].l = ihinfobuf1;
+            args[11].l = ihinfobuf2;
+            CALL_CONSTRUCTOR("hdf/hdf5lib/structs/H5O_info_t", "(JJIIJJJJJLhdf/hdf5lib/structs/H5O_hdr_info_t;Lhdf/hdf5lib/structs/H5_ih_info_t;Lhdf/hdf5lib/structs/H5_ih_info_t;)V", args);
+        }
+    }
 
     return ret_obj;
 } /* end Java_hdf_hdf5lib_H5_H5Oget_1info_1by_1idx */
@@ -315,14 +319,15 @@ Java_hdf_hdf5lib_H5_H5Olink
     herr_t      status = -1;
     const char *lDstName;
 
-    PIN_JAVA_STRING0(dst_name, lDstName);
-
-    status = H5Olink((hid_t)cur_loc_id, (hid_t)dst_loc_id, lDstName, (hid_t)create_id, (hid_t)access_id);
+    PIN_JAVA_STRING(dst_name, lDstName);
+    if (lDstName != NULL) {
+        status = H5Olink((hid_t)cur_loc_id, (hid_t)dst_loc_id, lDstName, (hid_t)create_id, (hid_t)access_id);
 
-    UNPIN_JAVA_STRING(dst_name, lDstName);
+        UNPIN_JAVA_STRING(dst_name, lDstName);
 
-    if (status < 0)
-        h5libraryError(env);
+        if (status < 0)
+            h5libraryError(env);
+    }
 } /* end Java_hdf_hdf5lib_H5_H5Olink */
 
 static herr_t
@@ -347,90 +352,71 @@ H5O_iterate_cb
         return -1;
     } /* end if */
     cls = CBENVPTR->GetObjectClass(CBENVPAR visit_callback);
-    if (cls == 0) {
-        /* printf("JNI H5O_iterate_cb error: GetObjectClass failed\n"); */
-        JVMPTR->DetachCurrentThread(JVMPAR);
-        return -1;
-    } /* end if */
-    mid = CBENVPTR->GetMethodID(CBENVPAR cls, "callback", "(JLjava/lang/String;Lhdf/hdf5lib/structs/H5O_info_t;Lhdf/hdf5lib/callbacks/H5O_iterate_t;)I");
-    if (mid == 0) {
-        /* printf("JNI H5O_iterate_cb error: GetMethodID failed\n"); */
-        JVMPTR->DetachCurrentThread(JVMPAR);
-        return -1;
+    if (cls != 0) {
+        mid = CBENVPTR->GetMethodID(CBENVPAR cls, "callback", "(JLjava/lang/String;Lhdf/hdf5lib/structs/H5O_info_t;Lhdf/hdf5lib/callbacks/H5O_iterate_t;)I");
+        if (mid != 0) {
+            str = CBENVPTR->NewStringUTF(CBENVPAR name);
+
+            args[0].i = (jint)info->hdr.version;
+            args[1].i = (jint)info->hdr.nmesgs;
+            args[2].i = (jint)info->hdr.nchunks;
+            args[3].i = (jint)info->hdr.flags;
+            args[4].j = (jlong)info->hdr.space.total;
+            args[5].j = (jlong)info->hdr.space.meta;
+            args[6].j = (jlong)info->hdr.space.mesg;
+            args[7].j = (jlong)info->hdr.space.free;
+            args[8].j = (jlong)info->hdr.mesg.present;
+            args[9].j = (jlong)info->hdr.mesg.shared;
+            // get a reference to the H5_hdr_info_t class
+            cls = CBENVPTR->FindClass(CBENVPAR "hdf/hdf5lib/structs/H5O_hdr_info_t");
+            if (cls != 0) {
+                // get a reference to the constructor; the name is <init>
+                constructor = CBENVPTR->GetMethodID(CBENVPAR cls, "<init>", "(IIIIJJJJJJ)V");
+                if (constructor != 0) {
+                    hdrinfobuf = CBENVPTR->NewObjectA(CBENVPAR cls, constructor, args);
+
+                    args[0].j = (jlong)info->meta_size.obj.index_size;
+                    args[1].j = (jlong)info->meta_size.obj.heap_size;
+                    // get a reference to the H5_ih_info_t class
+                    cls = CBENVPTR->FindClass(CBENVPAR "hdf/hdf5lib/structs/H5_ih_info_t");
+                    if (cls != 0) {
+                        // get a reference to the constructor; the name is <init>
+                        constructor = CBENVPTR->GetMethodID(CBENVPAR cls, "<init>", "(JJ)V");
+                        if (constructor != 0) {
+                            ihinfobuf1 = CBENVPTR->NewObjectA(CBENVPAR cls, constructor, args);
+                            args[0].j = (jlong)info->meta_size.attr.index_size;
+                            args[1].j = (jlong)info->meta_size.attr.heap_size;
+                            ihinfobuf2 = CBENVPTR->NewObjectA(CBENVPAR cls, constructor, args);
+
+                            args[0].j = (jlong)info->fileno;
+                            args[1].j = (jlong)info->addr;
+                            args[2].i = info->type;
+                            args[3].i = (jint)info->rc;
+                            args[4].j = (jlong)info->num_attrs;
+                            args[5].j = info->atime;
+                            args[6].j = info->mtime;
+                            args[7].j = info->ctime;
+                            args[8].j = info->btime;
+                            args[9].l = hdrinfobuf;
+                            args[10].l = ihinfobuf1;
+                            args[11].l = ihinfobuf2;
+                            // get a reference to the H5O_info_t class
+                            cls = CBENVPTR->FindClass(CBENVPAR "hdf/hdf5lib/structs/H5O_info_t");
+                            if (cls != 0) {
+                                // get a reference to the constructor; the name is <init>
+                                constructor = CBENVPTR->GetMethodID(CBENVPAR cls, "<init>", "(JJIIJJJJJLhdf/hdf5lib/structs/H5O_hdr_info_t;Lhdf/hdf5lib/structs/H5_ih_info_t;Lhdf/hdf5lib/structs/H5_ih_info_t;)V");
+                                if (constructor != 0) {
+                                    cb_info_t = CBENVPTR->NewObjectA(CBENVPAR cls, constructor, args);
+
+                                    status = CBENVPTR->CallIntMethod(CBENVPAR visit_callback, mid, g_id, str, cb_info_t, op_data);
+                                }
+                            }
+                        }
+                    }
+                }
+            }
+        }
     } /* end if */
-    str = CBENVPTR->NewStringUTF(CBENVPAR name);
-
-    args[0].i = (jint)info->hdr.version;
-    args[1].i = (jint)info->hdr.nmesgs;
-    args[2].i = (jint)info->hdr.nchunks;
-    args[3].i = (jint)info->hdr.flags;
-    args[4].j = (jlong)info->hdr.space.total;
-    args[5].j = (jlong)info->hdr.space.meta;
-    args[6].j = (jlong)info->hdr.space.mesg;
-    args[7].j = (jlong)info->hdr.space.free;
-    args[8].j = (jlong)info->hdr.mesg.present;
-    args[9].j = (jlong)info->hdr.mesg.shared;
-    // get a reference to the H5_hdr_info_t class
-    cls = CBENVPTR->FindClass(CBENVPAR "hdf/hdf5lib/structs/H5O_hdr_info_t");
-    if (cls == 0) {
-        JVMPTR->DetachCurrentThread(JVMPAR);
-        return -1;
-    } /* end if */
-    // get a reference to the constructor; the name is <init>
-    constructor = CBENVPTR->GetMethodID(CBENVPAR cls, "<init>", "(IIIIJJJJJJ)V");
-    if (constructor == 0) {
-        JVMPTR->DetachCurrentThread(JVMPAR);
-        return -1;
-    } /* end if */
-    hdrinfobuf = CBENVPTR->NewObjectA(CBENVPAR cls, constructor, args);
-
-    args[0].j = (jlong)info->meta_size.obj.index_size;
-    args[1].j = (jlong)info->meta_size.obj.heap_size;
-    // get a reference to the H5_ih_info_t class
-    cls = CBENVPTR->FindClass(CBENVPAR "hdf/hdf5lib/structs/H5_ih_info_t");
-    if (cls == 0) {
-        JVMPTR->DetachCurrentThread(JVMPAR);
-        return -1;
-    } /* end if */
-    // get a reference to the constructor; the name is <init>
-    constructor = CBENVPTR->GetMethodID(CBENVPAR cls, "<init>", "(JJ)V");
-    if (constructor == 0) {
-        JVMPTR->DetachCurrentThread(JVMPAR);
-        return -1;
-    } /* end if */
-    ihinfobuf1 = CBENVPTR->NewObjectA(CBENVPAR cls, constructor, args);
-    args[0].j = (jlong)info->meta_size.attr.index_size;
-    args[1].j = (jlong)info->meta_size.attr.heap_size;
-    ihinfobuf2 = CBENVPTR->NewObjectA(CBENVPAR cls, constructor, args);
-
-    args[0].j = (jlong)info->fileno;
-    args[1].j = (jlong)info->addr;
-    args[2].i = info->type;
-    args[3].i = (jint)info->rc;
-    args[4].j = (jlong)info->num_attrs;
-    args[5].j = info->atime;
-    args[6].j = info->mtime;
-    args[7].j = info->ctime;
-    args[8].j = info->btime;
-    args[9].l = hdrinfobuf;
-    args[10].l = ihinfobuf1;
-    args[11].l = ihinfobuf2;
-    // get a reference to the H5O_info_t class
-    cls = CBENVPTR->FindClass(CBENVPAR "hdf/hdf5lib/structs/H5O_info_t");
-    if (cls == 0) {
-        JVMPTR->DetachCurrentThread(JVMPAR);
-        return -1;
-    } /* end if */
-    // get a reference to the constructor; the name is <init>
-    constructor = CBENVPTR->GetMethodID(CBENVPAR cls, "<init>", "(JJIIJJJJJLhdf/hdf5lib/structs/H5O_hdr_info_t;Lhdf/hdf5lib/structs/H5_ih_info_t;Lhdf/hdf5lib/structs/H5_ih_info_t;)V");
-    if (constructor == 0) {
-        JVMPTR->DetachCurrentThread(JVMPAR);
-        return -1;
-    } /* end if */
-    cb_info_t = CBENVPTR->NewObjectA(CBENVPAR cls, constructor, args);
-
-    status = CBENVPTR->CallIntMethod(CBENVPAR visit_callback, mid, g_id, str, cb_info_t, op_data);
-
     JVMPTR->DetachCurrentThread(JVMPAR);
 
     return status;
@@ -453,17 +439,16 @@ Java_hdf_hdf5lib_H5_H5Ovisit
 
     if (op_data == NULL) {
         h5nullArgument(env, "H5Ovisit:  op_data is NULL");
-        return -1;
     } /* end if */
-    if (callback_op == NULL) {
+    else if (callback_op == NULL) {
         h5nullArgument(env, "H5Ovisit:  callback_op is NULL");
-        return -1;
     } /* end if */
+    else {
+        status = H5Ovisit((hid_t)grp_id, (H5_index_t)idx_type, (H5_iter_order_t)order, (H5O_iterate_t)H5O_iterate_cb, (void*)op_data);
 
-    status = H5Ovisit((hid_t)grp_id, (H5_index_t)idx_type, (H5_iter_order_t)order, (H5O_iterate_t)H5O_iterate_cb, (void*)op_data);
-
-    if (status < 0)
-        h5libraryError(env);
+        if (status < 0)
+            h5libraryError(env);
+    }
 
     return status;
 } /* end Java_hdf_hdf5lib_H5_H5Ovisit */
@@ -488,19 +473,21 @@ Java_hdf_hdf5lib_H5_H5Ovisit_1by_1name
         h5nullArgument(env, "H5Ovisit_by_name:  op_data is NULL");
         return -1;
     } /* end if */
-    if (callback_op == NULL) {
+    else if (callback_op == NULL) {
         h5nullArgument(env, "H5Ovisit_by_name:  callback_op is NULL");
         return -1;
     } /* end if */
+    else {
+        PIN_JAVA_STRING(name, lName);
+        if (lName != NULL) {
+            status = H5Ovisit_by_name((hid_t)grp_id, lName, (H5_index_t)idx_type, (H5_iter_order_t)order, (H5O_iterate_t)H5O_iterate_cb, (void*)op_data, (hid_t)access_id);
 
-    PIN_JAVA_STRING(name, lName, -1);
-
-    status = H5Ovisit_by_name((hid_t)grp_id, lName, (H5_index_t)idx_type, (H5_iter_order_t)order, (H5O_iterate_t)H5O_iterate_cb, (void*)op_data, (hid_t)access_id);
-
-    UNPIN_JAVA_STRING(name, lName);
+            UNPIN_JAVA_STRING(name, lName);
 
-    if (status < 0)
-        h5libraryError(env);
+            if (status < 0)
+                h5libraryError(env);
+        }
+    }
 
     return status;
 } /* end Java_hdf_hdf5lib_H5_H5Ovisit_1by_1name */
@@ -515,24 +502,20 @@ Java_hdf_hdf5lib_H5_H5Oset_1comment
     (JNIEnv *env, jclass clss, jlong loc_id, jstring comment)
 {
     herr_t      status = -1;
-    const char *oComment;
+    const char *oComment = NULL;
     jboolean    isCopy;
 
     if (comment == NULL) {
-        oComment = NULL;
+        status = H5Oset_comment((hid_t)loc_id, oComment);
     } /* end if */
     else {
         oComment = ENVPTR->GetStringUTFChars(ENVPAR comment, &isCopy);
-        if (oComment == NULL) {
-            h5JNIFatalError( env, "H5Oset_comment:  comment not pinned");
-            return;
-        } /* end if */
-    } /* end else */
-
-    status = H5Oset_comment((hid_t)loc_id, oComment);
+        if (oComment != NULL) {
+            status = H5Oset_comment((hid_t)loc_id, oComment);
 
-    if(oComment)
-        ENVPTR->ReleaseStringUTFChars(ENVPAR comment, oComment);
+            ENVPTR->ReleaseStringUTFChars(ENVPAR comment, oComment);
+        }
+    } /* end else */
 
     if (status < 0)
         h5libraryError(env);
@@ -552,30 +535,25 @@ Java_hdf_hdf5lib_H5_H5Oset_1comment_1by_1name
     const char *oName;
     const char *oComment;
 
-    PIN_JAVA_STRING0(name, oName);
-
-    if (comment == NULL) {
-        oComment = NULL;
-    } /* end if */
-    else {
-        jboolean    isCopy;
-        oComment = ENVPTR->GetStringUTFChars(ENVPAR comment, &isCopy);
-        if (oComment == NULL) {
-            UNPIN_JAVA_STRING(name, oName);
-            h5JNIFatalError( env, "H5Oset_comment_by_name:  comment not pinned");
-            return;
+    PIN_JAVA_STRING(name, oName);
+    if (oName != NULL) {
+        if (comment == NULL) {
+            status = H5Oset_comment_by_name((hid_t)loc_id, oName, NULL, (hid_t)access_id);
         } /* end if */
-    } /* end else */
-
-    status = H5Oset_comment_by_name((hid_t)loc_id, oName, oComment, (hid_t)access_id);
+        else {
+            jboolean    isCopy;
+            oComment = ENVPTR->GetStringUTFChars(ENVPAR comment, &isCopy);
+            if (oComment != NULL) {
+                status = H5Oset_comment_by_name((hid_t)loc_id, oName, oComment, (hid_t)access_id);
+                ENVPTR->ReleaseStringUTFChars(ENVPAR comment, oComment);
+            } /* end if */
+        } /* end else */
 
-    UNPIN_JAVA_STRING(name, oName);
-
-    if(oComment)
-        ENVPTR->ReleaseStringUTFChars(ENVPAR comment, oComment);
+        UNPIN_JAVA_STRING(name, oName);
 
-    if (status < 0)
-        h5libraryError(env);
+        if (status < 0)
+            h5libraryError(env);
+    }
 } /* end Java_hdf_hdf5lib_H5_H5Oset_1comment_1by_1name */
 
 /*
@@ -596,34 +574,30 @@ Java_hdf_hdf5lib_H5_H5Oget_1comment
     buf_size = H5Oget_comment((hid_t)loc_id, NULL, 0);
     if (buf_size < 0) {
         h5badArgument( env, "H5Oget_comment:  buf_size < 0");
-        return NULL;
-    } /* end if */
-    if (buf_size == 0) {
-        return NULL;
     } /* end if */
-
-    buf_size++; /* add extra space for the null terminator */
-    oComment = (char *)HDmalloc(sizeof(char) * (size_t)buf_size);
-    if (oComment == NULL) {
-        /* exception -- out of memory */
-        h5outOfMemory( env, "H5Oget_comment:  malloc failed");
-        return NULL;
-    } /* end if */
-
-    status = H5Oget_comment((hid_t)loc_id, oComment, (size_t)buf_size);
-
-    if (status >= 0) {
-        /*  may throw OutOfMemoryError */
-        str = ENVPTR->NewStringUTF(ENVPAR oComment);
-        HDfree(oComment);
-        if (str == NULL) {
-            h5JNIFatalError( env, "H5Oget_comment:  return string not allocated");
+    else if (buf_size > 0) {
+        buf_size++; /* add extra space for the null terminator */
+        oComment = (char *)HDmalloc(sizeof(char) * (size_t)buf_size);
+        if (oComment == NULL) {
+            /* exception -- out of memory */
+            h5outOfMemory( env, "H5Oget_comment:  malloc failed");
         } /* end if */
-    } /* end if */
-    else {
-        HDfree(oComment);
-        h5libraryError(env);
-    } /* end else */
+        else {
+            status = H5Oget_comment((hid_t)loc_id, oComment, (size_t)buf_size);
+
+            if (status < 0) {
+                h5libraryError(env);
+            } /* end if */
+            else {
+                /*  may throw OutOfMemoryError */
+                str = ENVPTR->NewStringUTF(ENVPAR oComment);
+                if (str == NULL) {
+                    h5JNIFatalError( env, "H5Oget_comment:  return string not allocated");
+                } /* end if */
+            } /* end else */
+            HDfree(oComment);
+        }
+    } /* end else if */
 
     return (jstring)str;
 } /* end Java_hdf_hdf5lib_H5_H5Oget_1comment */
@@ -643,43 +617,37 @@ Java_hdf_hdf5lib_H5_H5Oget_1comment_1by_1name
     ssize_t     status;
     jstring     str = NULL;
 
-    PIN_JAVA_STRING(name, oName, NULL);
-
-    /* get the length of the comment */
-    buf_size = H5Oget_comment_by_name((hid_t)loc_id, oName, NULL, 0, (hid_t)access_id);
-    if (buf_size < 0) {
-        UNPIN_JAVA_STRING(name, oName);
-        h5badArgument( env, "H5Oget_comment_by_name:  buf_size < 0");
-        return NULL;
-    } /* end if */
-    if (buf_size == 0) {
-        UNPIN_JAVA_STRING(name, oName);
-        return NULL;
-    } /* end if */
-
-    buf_size++; /* add extra space for the null terminator */
-    oComment = (char *)HDmalloc(sizeof(char) * (size_t)buf_size);
-    if (oComment == NULL) {
-        UNPIN_JAVA_STRING(name, oName);
-        h5outOfMemory( env, "H5Oget_comment_by_name:  malloc failed");
-        return NULL;
-    } /* end if */
-
-    status = H5Oget_comment_by_name((hid_t)loc_id, oName, oComment, (size_t)buf_size, (hid_t)access_id);
-    UNPIN_JAVA_STRING(name, oName);
-
-    if (status >= 0) {
-        /*  may throw OutOfMemoryError */
-        str = ENVPTR->NewStringUTF(ENVPAR oComment);
-        HDfree(oComment);
-        if (str == NULL) {
-            h5JNIFatalError( env, "H5Oget_comment_by_name:  return string not allocated");
+    PIN_JAVA_STRING(name, oName);
+    if (oName != NULL) {
+        /* get the length of the comment */
+        buf_size = H5Oget_comment_by_name((hid_t)loc_id, oName, NULL, 0, (hid_t)access_id);
+        if (buf_size < 0) {
+            h5badArgument( env, "H5Oget_comment_by_name:  buf_size < 0");
         } /* end if */
-    } /* end if */
-    else {
-        HDfree(oComment);
-        h5libraryError(env);
-    } /* end else */
+        else if (buf_size > 0) {
+            buf_size++; /* add extra space for the null terminator */
+            oComment = (char *)HDmalloc(sizeof(char) * (size_t)buf_size);
+            if (oComment == NULL) {
+                h5outOfMemory( env, "H5Oget_comment_by_name:  malloc failed");
+            } /* end if */
+            else {
+                status = H5Oget_comment_by_name((hid_t)loc_id, oName, oComment, (size_t)buf_size, (hid_t)access_id);
+
+                if (status < 0) {
+                    h5libraryError(env);
+                } /* end if */
+                else {
+                    /*  may throw OutOfMemoryError */
+                    str = ENVPTR->NewStringUTF(ENVPAR oComment);
+                    if (str == NULL) {
+                        h5JNIFatalError( env, "H5Oget_comment_by_name:  return string not allocated");
+                    } /* end if */
+                } /* end else */
+                HDfree(oComment);
+            }
+        } /* end if */
+        UNPIN_JAVA_STRING(name, oName);
+    }
 
     return (jstring)str;
 } /* end Java_hdf_hdf5lib_H5_H5Oget_1comment_1by_1name */
@@ -696,16 +664,17 @@ Java_hdf_hdf5lib_H5_H5Oexists_1by_1name
     htri_t      bval = JNI_FALSE;
     const char *oName;
 
-    PIN_JAVA_STRING(name, oName, JNI_FALSE);
-
-    bval = H5Oexists_by_name((hid_t)loc_id, oName, (hid_t)access_id);
+    PIN_JAVA_STRING(name, oName);
+    if (oName != NULL) {
+        bval = H5Oexists_by_name((hid_t)loc_id, oName, (hid_t)access_id);
 
-    UNPIN_JAVA_STRING(name, oName);
+        UNPIN_JAVA_STRING(name, oName);
 
-    if (bval > 0)
-        bval = JNI_TRUE;
-    else if (bval < 0)
-        h5libraryError(env);
+        if (bval > 0)
+            bval = JNI_TRUE;
+        else if (bval < 0)
+            h5libraryError(env);
+    }
 
     return (jboolean)bval;
 } /* end Java_hdf_hdf5lib_H5_H5Oexists_1by_1name */
@@ -767,14 +736,15 @@ Java_hdf_hdf5lib_H5__1H5Oopen_1by_1idx
     hid_t       retVal = -1;
     const char *oName;
 
-    PIN_JAVA_STRING(name, oName, -1);
+    PIN_JAVA_STRING(name, oName);
+    if (oName != NULL) {
+        retVal = H5Oopen_by_idx((hid_t)loc_id, oName, (H5_index_t)index_field, (H5_iter_order_t)order, (hsize_t)link_n, (hid_t)lapl_id );
 
-    retVal = H5Oopen_by_idx((hid_t)loc_id, oName, (H5_index_t)index_field, (H5_iter_order_t)order, (hsize_t)link_n, (hid_t)lapl_id );
+        UNPIN_JAVA_STRING(name, oName);
 
-    UNPIN_JAVA_STRING(name, oName);
-
-    if (retVal < 0)
-        h5libraryError(env);
+        if (retVal < 0)
+            h5libraryError(env);
+    }
 
     return (jlong)retVal;
 } /* end Java_hdf_hdf5lib_H5__1H5Oopen_1by_1idx */
@@ -786,7 +756,7 @@ Java_hdf_hdf5lib_H5__1H5Oopen_1by_1idx
  */
 JNIEXPORT void JNICALL
 Java_hdf_hdf5lib_H5_H5Oflush
-	(JNIEnv *env, jclass clss, jlong loc_id)
+    (JNIEnv *env, jclass clss, jlong loc_id)
 {
     if (H5Oflush((hid_t)loc_id) < 0)
         h5libraryError(env);
@@ -799,7 +769,7 @@ Java_hdf_hdf5lib_H5_H5Oflush
  */
 JNIEXPORT void JNICALL
 Java_hdf_hdf5lib_H5_H5Orefresh
-	(JNIEnv *env, jclass clss, jlong loc_id)
+    (JNIEnv *env, jclass clss, jlong loc_id)
 {
     if (H5Orefresh((hid_t)loc_id) < 0)
         h5libraryError(env);