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import java.lang.reflect.*;
// My best guess at this point is that each additional class takes
// about 200 bytes (maybe as many as 400-500) of additional storage.
// An empty class extending Object also takes about 200 bytes on disk.
// So the cost of using inner classes to handle e.g. ActionEvents is not
// that high, unless you have many thousands of such handlers.
// Based on simple greps, I estimate KiNG has less than 150 functions
// handled by ReflexiveAction. The additional cost (besides readability)
// to have used "real" classes would probably be ~30 kB.
// To generate the classes B*, do one of the following:
// for((i=0;i<1000;i++)); do echo "public class B$i { public void foo() { System.out.println(\"This is class B$i\"); } }" > B${i}.java; done
// for((i=0;i<1000;i++)); do echo "public class B$i { }" > B${i}.java; done
public class A
{
public static void main(String[] args)
{
Object[] b = new Object[1000];
Runtime r = Runtime.getRuntime();
long before, after;
System.gc();
System.gc();
System.gc();
System.gc();
System.gc();
try { Thread.sleep(2000); } catch(InterruptedException ex) {}
System.out.println("Checking memory used by a single new class.");
before = r.totalMemory() - r.freeMemory();
System.out.println("Before: "+before);
try
{
for(int i = 0; i < b.length; i++)
{
Class cl = Class.forName("B"+i);
Constructor co = cl.getConstructor();
b[i] = co.newInstance();
System.out.println(" Used: "+((r.totalMemory() - r.freeMemory() - before) / (i+1)));
}
}
catch(Exception ex) { ex.printStackTrace(); }
System.gc();
System.gc();
System.gc();
System.gc();
System.gc();
try { Thread.sleep(2000); } catch(InterruptedException ex) {}
after = r.totalMemory() - r.freeMemory();
System.out.println("After: "+after);
System.out.println("Diff: "+(after-before));
System.out.println("Each: "+((after-before)/b.length));
}
}
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