Java String 类的 equals 和 ==

public class Test_String {
public static void main(String[] args) {
String a = new String("aa");
String b = new String("aa");
System.out.println(a == new String("aa")); //false               == 判断 指向的是不是同一个对象 new 时会创建对象
System.out.println("a == b " + (a == b)); //false
System.out.println("a.equals(b) " + (a.equals(b))); //true      a.equals(b)判断两个对象的内容是否相等
System.out.println(a.equals(new String("aa"))); //true
}

}