== ，equals与matches,contains的差异

== ，equals与matches,contains的区别

public static void main(String[] args) {
  String s = "welcome to java";
  String s1 = new String("welcome to java");
  System.out.println(s.equals(s1));
  System.out.println(s==s1);//==运算符只能检测s与s1是否指向相同的对象，equals比较它们的内容
}

public static void main(String[] args) {
  String s = "abc.*";
  String s1 = "abcffff";
  System.out.println(s1.equals(s));//false
  System.out.println(s1.matches(s));//true 用".*"匹配后面的字符
}