Easily measure the size of Java Objects


import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.ObjectOutput;
import java.io.ObjectOutputStream;

public class ObjectUtils {
	public static int getObjectSize(Object o) {
		ObjectOutput out = null;
		try (ByteArrayOutputStream bos = new ByteArrayOutputStream()) {
			out = new ObjectOutputStream(bos);
			byte[] b = bos.toByteArray();
			return b.length;
		} catch (IOException e) {
			return -1;

How to use

	public static void main(String[] args) {
			String o = "ABC";
			Integer o = 100;
			String[] o = { "ABC", "ABC", "ABC" };

Execution result example


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