How can we find size of the object ?

Answers were Sorted based on User's Feedback

Answer / niranjanravi

there is no sizeOf() in java to find the size of the object

Is This Answer Correct ?    8 Yes 4 No

Answer / m!r@

public class FindSizeOfObject{
public static void main(String[] args) throws Exception{

Runtime obj = Runtime.getRuntime();
System.out.println(obj.totalMemory() - obj.freeMemory());

Is This Answer Correct ?    1 Yes 1 No

Answer / lachha g

you can use Instrumentation class.

use long getObjectSize(Object objectToSize) method.
It returns amount of storage consumed by the specified object.
package Test;

import java.lang.instrument.Instrumentation;

public class ObjectSize {
private int x;
private int y;

ObjectSize(int x, int y){

public static void main(String [] args) {
ObjectSize obj= new ObjectSize(2,4);
class Test {
private static Instrumentation instrumentation;

public static void premain(String args, Instrumentation inst) {
instrumentation = inst;

public static long getObjectSize(Object o) {
return instrumentation.getObjectSize(o);

Is This Answer Correct ?    0 Yes 0 No

Answer / sitaram

we don't have any method for to identify the size of object
in java.

Is This Answer Correct ?    0 Yes 2 No

Answer / suvarna

getObjectSize(Object objectToSize)
Returns an implementation-specific approximation
of the amount of storage consumed by the specified object.

Is This Answer Correct ?    0 Yes 3 No

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