java开发中怎样判断String字符串包含另外一个字符串

1. 使用contains()方法

String str1 = “Hello World”;
String str2 = “Hello”;
boolean contains = str1.contains(str2);
System.out.println(contains); // true

2. 使用indexOf()方法

String str1 = “Hello World”;
String str2 = “Hello”;
int index = str1.indexOf(str2);
boolean contains = index != -1;
System.out.println(contains); // true

3. 使用matches()方法

String str1 = “Hello World”;
String str2 = “Hello.*”;
boolean contains = str1.matches(str2);
System.out.println(contains); // true

4. 使用Pattern和Matcher类

String str1 = “Hello World”;
String str2 = “Hello”;<