To Find Java Object Size using serialization

Question

I have been struggling for finding the exact size of java objects. I have tried different options and non of them are working correctly. Then I tried to serialize the object and find the size of the serialized object. The size of the serialized object is very small, like in few kilo byte. So I doubted my method. I was wondering is it the correct way? Is there any problem you people see in this procedure? Please help...

Possible duplicate of http://stackoverflow.com/questions/52353/in-java-what-is-the-best-way-to-determine-the-size-of-an-object — Invisible Arrow, Jan 06 '15 at 06:54
What makes you think your object is larger than a few kilobytes? — user207421, Jan 06 '15 at 07:17
The serialized size of an object is not the same as the amount of memory it consumes on the Java heap. — Louis Wasserman, Jan 06 '15 at 19:22

score 1 · Answer 1 · edited Jan 06 '15 at 07:03

You can convert your object into a byte array using ObjectOutputStream and ByteArrayOutputStream:

public static int sizeof(Object obj) throws IOException {

    ByteArrayOutputStream byteOutputStream = new ByteArrayOutputStream();
    ObjectOutputStream objectOutputStream = new ObjectOutputStream(byteOutputStream);

    objectOutputStream.writeObject(obj);
    objectOutputStream.flush();
    objectOutputStream.close();

    return byteOutputStream.toByteArray().length;
}

To Find Java Object Size using serialization

1 Answers1