This tiny class sped up my reflection stuff by a factor of 3 (minimum!).
The idea behind: avoid the costly .getField() by hashing.
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| 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;
}
} |
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| fieldhash.getField(myclass,"myvariable"); |
is about 25x
faster than
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| myclass.getField("myvariable"); |
