#

# Copyright (c) 2004, 2007, Oracle and/or its affiliates. All rights reserved.

#

# Redistribution and use in source and binary forms, with or without

# modification, are permitted provided that the following conditions

# are met:

#

#   - Redistributions of source code must retain the above copyright

#     notice, this list of conditions and the following disclaimer.

#

#   - Redistributions in binary form must reproduce the above copyright

#     notice, this list of conditions and the following disclaimer in the

#     documentation and/or other materials provided with the distribution.

#

#   - Neither the name of Oracle nor the names of its

#     contributors may be used to endorse or promote products derived

#     from this software without specific prior written permission.

#

# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS

# IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,

# THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR

# PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR

# CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,

# EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,

# PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR

# PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF

# LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING

# NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS

# SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

#

heapViewer

This agent library demonstrates how to get an easy view of the

heap in terms of total object count and space used.

It uses GetLoadedClasses(), SetTag(), and IterateThroughHeap()

to count up all the objects of all the current loaded classes.

The heap dump will happen at the event JVMTI_EVENT_VM_DEATH, or the

event JVMTI_EVENT_DATA_DUMP_REQUEST.

It also demonstrates some more robust agent error handling using 

GetErrorName(),

Using the heap iterate functions, lots of statistics can be generated

without resorting to using Byte Code Instrumentation (BCI).

You can use this agent library as follows:

    java -agentlib:heapViewer ...

To get help on the available options try:

    java -agentlib:heapViewer=help

See ${JAVA_HOME}/demo/jvmti/index.html for help running and building agents.