SizeOfObj

Estimate the size of the Java objects.
To get accurate estimates, use a tool like JOL
This is old code with a big sizeOf() method.
I found it on an old spinning rust disk and want to save it here

Build and Test

execute test.sh to run some basic tests, uses build.sh to build the stuff.

Usage

Drop SizeOfObj.java somewhere into your package structure(modify the package) and use it like this:

public static void main(String... strings)
{
	class Output
	{
		long[] la = { -1 };
		String str = "str";
	}

	PrintWriter out = new PrintWriter(System.out);
	long size = SizeOfObj.sizeOf(new Output(), out, out);
	System.out.println("Size: " + size + " bytes");
}

Output:

{Output: #1
  la : [long[]: #2
    0) : -1  ~8B
  ]  ~24B
  str : {String: #3
    coder : 0  ~1B
    hash : 0  ~4B
    hashIsZero : false  ~1B
    value : [byte[]: #4
      0) : 115  ~1B
      1) : 116  ~1B
      2) : 114  ~1B
    ]  ~24B
  }  ~24B
}  ~24B
ObjSize: ~96 Bytes

Count       Sum         DESCRIPTION 
1           24          [B          
1           24          [J          
1           24          de.codecoverage.utils.TestDriver$Output
1           24          java.lang.String
4           96          Sum total   
Size: 96 bytes

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