ReflectionSpeed.java

package ch.qos.logback.reflect;

import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;

public class ReflectionSpeed {

  static final Class[] EMPTY_CLASS_PARAM = new Class[] {};
  static final Object[] EMPTY_OBJECT_PARAM = new Object[] {};
  
  public static void main(String[] args) throws Exception {
    
    Fruit f = new Fruit("red", true);
    
    Class fruitClass = Fruit.class;
    Method getColorMethod = fruitClass.getDeclaredMethod("getColor", EMPTY_CLASS_PARAM);
    loop(getColorMethod, f);
    loop(getColorMethod, f);
    loop(getColorMethod, f);
  }
  
  static void loop(Method getColorMethod, Fruit fruit) throws IllegalArgumentException, IllegalAccessException, InvocationTargetException {
    final int LEN = 100*1000;
    
    long start = System.nanoTime();
    for(int i = 0; i < LEN; i++) {
      getColorMethod.invoke(fruit, EMPTY_OBJECT_PARAM );
    }

    long end = System.nanoTime();
    System.out.println("avg: "+((end-start)/LEN)+" nanos");
  }

  
}