Java String 字符串中包含某个string

Stirng中包含某个string(真为true 假为false)

        String string = "www.baidu.com";
        boolean test1 = string.contains("a");
        boolean test2 = string.contains(".");
        boolean test3 = string.contains("ww");
        boolean test4 = string.contains("cm");
        boolean test5 = string.contains("1234");

结果