Getting the Size of the Java Memory Heap
The heap is the area in memory in which objects are created.
// Get current size of heap in bytes
long heapSize = Runtime.getRuntime().totalMemory();
// Get maximum size of heap in bytes. The heap cannot grow beyond this size.
// Any attempt will result in an OutOfMemoryException.
long heapMaxSize = Runtime.getRuntime().maxMemory();
// Get amount of free memory within the heap in bytes. This size will increase
// after garbage collection and decrease as new objects are created.
long heapFreeSize = Runtime.getRuntime().freeMemory();
Is it possible to find how much of memory occupied by a file
public long occupiedMemory(String filePath){
//TODO - Calculate
return occupiedMemoryBytheFile;
}