Reflection speedup: hashed Fields

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#1

This tiny class sped up my reflection stuff by a factor of 3 (minimum!).
The idea behind: avoid the costly .getField() by hashing.

import java.lang.reflect.Field;
import java.util.HashMap;

public class FieldHash extends HashMap<Class, HashMap<String, Field>> {
	public Field getField(Class c, String fieldname) throws SecurityException, NoSuchFieldException {
		HashMap<String, Field> h = get(c);
		if (h == null) {
			put(c, h = new HashMap());
		}
		Field f = h.get(fieldname);
		if (f == null) {
			h.put(fieldname, f = c.getField(fieldname));
		}
		return f;
	}
}


 fieldhash.getField(myclass,"myvariable");

is about 25x :smiley: faster than

 myclass.getField("myvariable");