alan2448的博客

Java StringBuilder与StringBuffer相同点：都继承了AbstractStringBuilder类提供可变字符串的功能如：append/insert/delete/replace不同点：StringBuffer是线程安全的，StringBuilder不保证线程安全，StringBuffer使用synchronized对其修改字符串的方法加锁。StringBuilder在绝大多数情况下比StringBuffer更快。...

1.继承Thread类public class MyThread_1 extends Thread { private int ThreadId; private int runCount; private String ImplementMethod = "继承Thread类"; private int workCount; public MyThread_1(int i,int workCount){ this.ThreadId = i;

Java集合（OpenJDK11）----Java笔记