如何为Java成绩管理程序添加及格/不及格判断逻辑？

Got it, let's get this sorted for you! The perfect spot to add your pass/fail check is in the printAverageGrade() method—since that's where you're already calculating and displaying the average grade.

Here's the step-by-step fix:

1. First, store the calculated average in a variable (this makes your code cleaner and avoids re-calculating the average multiple times).
2. Add your if-else statement right after printing the average to check if it's below 80, then output the corresponding result.

Modified printAverageGrade() Method #

private void printAverageGrade() {
    double average = getAverage(subjects); // Store average in a variable
    System.out.println("Total of grades: " + getSum(subjects));
    System.out.println("Count of grades: " + subjects.length);
    System.out.println("Your average grade is: " + average);
    
    // Your pass/fail logic here
    if (average < 80) {
        System.out.println("failed");
    } else {
        System.out.println("passed");
    }
    System.out.println();
}

Optional: Combine Output into One Line #

If you prefer to show the average and result in a single line, you can adjust the code like this:

private void printAverageGrade() {
    double average = getAverage(subjects);
    System.out.println("Total of grades: " + getSum(subjects));
    System.out.println("Count of grades: " + subjects.length);
    
    // Combine average and result in one print statement
    System.out.print("Your average grade is: " + average + " - ");
    if (average < 80) {
        System.out.println("failed");
    } else {
        System.out.println("passed");
    }
    System.out.println();
}

Why This Works #

The issue you were facing is that you can't embed an if statement directly inside a System.out.print() call—if is a control flow statement, not an expression you can inline like that. By first storing the average in a variable, you can easily reference it in your condition check and output the result separately.

内容的提问来源于stack exchange，提问作者user8572431