性能分析对比

package com.test5;

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

//分析性能问题
public class test10 {
	// 普通方法调用
	public static void test01() {
		User user = new User();
		long startTime = System.currentTimeMillis();
		for (int i = 0; i < 10_0000_0000; i++) {
			user.getName();
		}
		long endTime = System.currentTimeMillis();
		System.out.println("普通方法执行10亿次:" + (endTime - startTime) + "ms");
	}

	// 反射方式调用
	public static void test02() throws NoSuchMethodException, SecurityException, IllegalAccessException,
			IllegalArgumentException, InvocationTargetException {
		User user = new User();
		Class c1 = user.getClass();
		Method getname = c1.getDeclaredMethod("getName", null);
		long startTime = System.currentTimeMillis();
		for (int i = 0; i < 10_0000_0000; i++) {
			getname.invoke(user, null);
		}
		long endTime = System.currentTimeMillis();
		System.out.println("反射方法执行10亿次:" + (endTime - startTime) + "ms");
	}

	// 反射方式调用 关闭检测
	public static void test03() throws NoSuchMethodException, SecurityException, IllegalAccessException,
			IllegalArgumentException, InvocationTargetException {
		User user = new User();
		Class c1 = user.getClass();
		Method getname = c1.getDeclaredMethod("getName", null);
		getname.setAccessible(true);
		long startTime = System.currentTimeMillis();
		for (int i = 0; i < 10_0000_0000; i++) {
			getname.invoke(user, null);
		}
		long endTime = System.currentTimeMillis();
		System.out.println("关闭检测执行10亿次:" + (endTime - startTime) + "ms");
	}

	public static void main(String[] args) throws NoSuchMethodException, SecurityException, IllegalAccessException,
			IllegalArgumentException, InvocationTargetException {
		test01();
		test02();
		test03();
		/* 运行结果
		 * 普通方法执行10亿次:5ms 
		 * 反射方法执行10亿次:2225ms 
		 * 关闭检测执行10亿次:1124ms
		 */
	}
}