Java8 String类基础API

@Test
void test01(){

    String s = " 天鹅湖很美丽,天鹅湖并不怎么好看 ";
    String ss = "天鹅湖并不怎么好看";


    // 判断两个对象内容是否相等
    System.out.println(s.equals(ss));

    // 截取字符串
    System.out.println(s.substring(0, 3));

    //判断是字符串以什么开始的
    System.out.println(s.startsWith("天鹅"));
   //字符串长度
    System.out.println(s.length());

    //判断一个字符是否包含
    System.out.println(s.contains("天鹅湖"));
    //替换
    System.out.println(s.replace("好看", "漂亮"));
    //去除首尾空格
    System.out.println(s.trim());
    //判断字符串是否为空
    System.out.println(s.isEmpty());
    System.out.println("+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++");
    //字符串随意位置拼接*/
    final boolean b = s.contains("丽");
    if (b){
        final int l = s.indexOf("丽");
        final String de = s.substring(0, l+1);
        String a ;
        a = de.concat("DE").concat(s.substring(l+1));
        System.out.println(a);

    }

//方式二
    StringBuffer stringBuffer = new StringBuffer();
    System.out.println(stringBuffer.append(s).insert(7, "的"));


}