kkgbn的博客

public class StopWatchTest { //执行计时 private final StopWatch watch; public StopWatchTest(){ this.watch = new StopWatch(); } public void test(){ int n = 10000; while(n-->0){ System.out.pri

Constructor constr = targetClass.getDeclaredConstructor(); constr.setAccessible(true); Object inst = constr.newInstance(); Accessable属性是继承自AccessibleObject 类. 功能是启用或禁用安全检查 使用了method.setAccessible(tr

可以获取真正的IP public static String getRealIpAddr(HttpServletRequest req) { String ip = req.getHeader("x-forwarded-for"); if(ip == null || ip.length() == 0 ||"unknown".equalsIgnoreCase(ip)) {

这么考虑的 相当于一个盒子里有很多小球，

洗牌，现理解就是讲一组数组打算顺序