使用Objects.toString将值转换为String

import java.util.Objects;
/*来自 n o w j a v a . c o m - 时  代  Java*/

public class Main {

  public static void main(String[] args) {

    // toString() method test

    System.out.println("toString(null) is " + Objects.toString(null));

    System.out.println("toString(null, \"XXX\") is " + Objects.toString(null, "XXX"));

  }


}