基础深化和提高-java反射技术

package com.tong; import java.lang.reflect.Method; public class Test { public static void main(String[] args) { try { //反射耗时 long reflectStart = System.currentTimeMillis(); Class clazz = Class.forName("com.tong.Users"); Users users = (Users) clazz.getConstructor(null).newInstance(); Method method = clazz.getMethod("setUsername", String.class); //忽略安全检查 method.setAccessible(true); for(int i=0;i<100000000;i++){ method.invoke(users,"Oldlu"); } long reflectEnd = System.currentTimeMillis(); //非反射方式的耗时 long start = System.currentTimeMillis(); Users users1 = new Users(); for(int i=0;i<100000000;i++){ users1.setUsername("oldlu"); } long end = System.currentTimeMillis(); System.out.println("反射执行时间："+(reflectEnd - reflectStart)); System.out.println("普通方法执行时间："+(end-start)); } catch (Exception e) { e.printStackTrace(); } } }