使用Bluej无法打印阵列

Question

I'm trying to print a file which is separated lines of integers and I want to print the values after loading into an Array, so that I can process and printout the min, max, mean, median, etc.

Here is my code below, but it only prints out 2000 :

   String txt = UIFileChooser.open();
    this.data = new int[2000];
    int count = 0;
    try {
        Scanner scan = new Scanner(new File(txt));
        while (scan.hasNextInt() && count<data.length){
            this.data[count] = scan.nextInt();
            count++;
        }
        scan.close();
    }
    catch (IOException e) {UI.println("Error");
    }
     {UI.printf("Count:  %d\n", this.data.length);
    }

Answer 1

The reason you are getting 2000 as your output every time is because you are only printing out the entire length of the array, which you define as 2000 in the line this.data = new int[2000]; . To print out the number of values in the array, the simplest way would just be to use count , because it already holds that number. To print out all the values in the array, simply loop through the array up to the last value, printing each one. Code examples are below:

String txt = UIFileChooser.open();
this.data = new int[2000];
int count = 0;
try {
    Scanner scan = new Scanner(new File(txt));
    while (scan.hasNextInt() && count < data.length){
        this.data[count] = scan.nextInt();
        count++;
    }
    scan.close();
}
catch (IOException e) {
    UI.println("Error");
}

// this line will print the length of the array,
// which will always be 2000 because of line 2
UI.printf("Count:  %d\n", this.data.length);

// this line will print how many values are in the array
UI.printf("Values in array: %d\n", count);

// now to print out all the values in the array
for (int i = 0; i < count; i++) {
    UI.printf("Value: %d\n", this.data[i]);
}

// you can use the length of the array to loop as well
// but if count < this.data.length, then everything
// after the final value will be all 0s
for (int i = 0; i < this.data.length; i++) {
    UI.printf("Value: %d\n", this.data[i]);
}