Java-获取子字符串的索引位置

package demo4;

public class Demo9 {

  public static void main(String[] args) {
    // TODO Auto-generated method stub
    //获取第一次出现的索引
//        String str ="We are the world";
//        int index =  str.indexOf("e");
//        int index1 =  str.indexOf("e",3);
//        System.out.println(index);
//        System.out.println(index1);
    //获取倒数第一次出现的索引
      String str ="Let it go! Let it go!";
      int lastindex = str.lastIndexOf("t");
      int lastindex1 = str.lastIndexOf("t",14);
      System.out.println(lastindex);
      System.out.println(lastindex1);
  }

}