小编Ibo*_*nes的帖子

当我尝试使用表达式时,value -> value我得到一个错误,表示不支持Lambda.我目前正在使用1.8 JDK和Lambda支持,但我仍然得到错误.我的猜测是它是IntelliJ 13.1.4,但我并不积极.

public static void grades(){
    final List<Integer> grade = new ArrayList<Integer>();
    int gradelistnumber = 1;
    int inputedgrade = 0;

    while(inputedgrade != -1){
        System.out.println("Enter Grade for student " + gradelistnumber + " (1-50): ");
        inputedgrade = sc.nextInt();
        grade.add(inputedgrade);
        gradelistnumber++;


    }

    System.out.println("Class Average: " + System.out.println(grade.stream().mapToInt(value -> value /*error*/).sum()));
  }

}

基本上我试图制作一个程序,允许教师为每个学生输入考试成绩,然后在他们输入成绩后,它给教师一个他们输入的所有成绩的总和

public static void grades(){
    List<Integer> grade = new ArrayList<Integer>();
    int gradetotal = IntStream.of(grades).sum;/* sum */
    int gradelistnumber = 1;
    int inputedgrade = 0;

    while(inputedgrade != -1){
        System.out.println("Enter Grade for student " + gradelistnumber + " (1-50): ");
        inputedgrade = sc.nextInt();
        grade.add(inputedgrade);
        gradelistnumber++;


    }

    System.out.println("Class Average: " + gradetotal / 50 * 100);
}

我正在试图弄清楚如何获得数组列表等级的总和.