get heap dump

get into command line.
use jmap tool which can be located within bin directory of your jdk installation directory.
you can run it alone and see all of its parameters or use this example:
"jmap -dump:format=b,file=heap.bin [pid]"
[pid] should be replaced with the appropriate process identifier (use task manager to get it).
Hopefully that helps a bit,
Dor

read heap dump

I suggest using eclipse MAT plug in, which can be found here.
After installing the plug in, use file->Open and open the heap.bin you have created (jmap for example).
It will take a while, depends on your computer hardware, but in the end, you would be able to analyaze this memory dump.
Hopefully it helps,
DOr