Originally authored by Dimitris Andreou (jim.andreou@gmail.com).
See package javadocs for information.
Quick tip: To use the MemoryMeasurer (to measure the footprint of an object graph in bytes), this parameter needs to be passed to th VM: -javaagent:path/to/object-explorer.jar
This library was forked when it used to exist on Google Code only. In the meantime the original author moved the code to github as well (DimitrisAndreou/memory-measurer), however it appears that the library is not actively maintained any more.