print out object with handy way

Question

I made a code using my No2 class but I'm confused about how to print out entire code without using array.

I just know one way to print out this code, I'm using System.out.println() 7 times.

Please help me to figure out another way/handy way to do it.

    public static void main(String[] args) {
         No2 a1 = new No2("1","A",3,6000);
         No2 a2 = new No2("2","B",4,8000);
         No2 a3 = new No2("3","C",1,1000);
         No2 a4 = new No2("4","D",2,4000);
         No2 a5 = new No2("5","E",5,10000);
         No2 a6 = new No2("6","F",2,4000);
         No2 a7 = new No2("7","G",3,6000);
   }

I just want to find another way to print out it, but yet to find another way — Okem, Nov 11 '14 at 15:32
Are you against any sort of collection? Can you use an ArrayList? or a List? If you can't use a collection, then you won't get much better than the above. — AdamMc331, Nov 11 '14 at 15:36
I just don't understand about ArrayList or List. whether we can use looping for print out code above ? — Okem, Nov 11 '14 at 15:44
If you're willing to learn about them, beyonddc's answer is a good one. — AdamMc331, Nov 11 '14 at 15:45
Also, here's the [documentation](https://docs.oracle.com/javase/7/docs/api/java/util/ArrayList.html) if you are interested. Regardless of whether or not you use it here, Lists are a must-have skill in my opinion. — AdamMc331, Nov 11 '14 at 15:46
possible duplicate of [Java Reflection: How to get the name of a variable?](http://stackoverflow.com/questions/744226/java-reflection-how-to-get-the-name-of-a-variable) — Narmer, Nov 11 '14 at 15:54

score 2 · Accepted Answer · answered Nov 11 '14 at 15:38

2

    public static void main(String[] args) {
        final List<No2> no2List = new ArrayList<No2>();
        no2List.add(new No2("1","A",3,6000));
        no2List.add(new No2("2","B",4,8000));
        no2List.add(new No2("3","C",1,1000));
        no2List.add(new No2("4","D",2,4000));
        no2List.add(new No2("5","E",5,10000));
        no2List.add(new No2("6","F",2,4000));
        no2List.add(new No2("7","G",3,6000));

        for (final No2 no2 : no2List) {
            System.out.println(no2.toString());
        }
    }

You'll need to implement the toString() method in No2 class. Also you'll need to import java.util.List and java.util.ArrayList in your main class.

That should do the trick for you.

answered Nov 11 '14 at 15:38

beyonddc

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Is `final` required in the for loop? I've never seen it used there before. – AdamMc331 Nov 11 '14 at 15:39
Not required, just a habit. You're just preventing a variable from being reassign to something else. – beyonddc Nov 11 '14 at 15:41
+1 for teaching me something new, and for a good answer, of course. – AdamMc331 Nov 11 '14 at 15:45

Narmer · Answer 2 · 2014-11-11T15:52:24.890

You could override the toString method in your No2 class to prettify your output. I'm totally guessing here:

@Override
public String toString(){
    return "id: " + id + ", " +  
           "letter: " + letter + ", " +
           "number: " + number+ ", " +
           "bigNumber: " + bigNumber;
}

I'm afraid that, without using a Collection, your task is nearly impossible (and quite useless). You can tough use a single println for your objects:

System.out.println(a1.toString() + "\n" +
                   a2.toString() + "\n" +
                   a3.toString() + "\n" +
                   a4.toString() + "\n" +
                   a5.toString() + "\n" +
                   a6.toString() + "\n" +
                   a7.toString() + "\n");

which is pretty ugly.

score -1 · Answer 3 · answered Nov 11 '14 at 15:33

-1

You can implement toString method in your No2 Class, then use an array to store your variables :

array[0] = new No2("1","A",3,6000);
// ...
// Then try this line of code
Arrays.toString(array);

Good luck.

answered Nov 11 '14 at 15:33

teeyo

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Though this is the correct answer design-wise, he said specifically he doesn't want to use an array. – DejaVuSansMono Nov 11 '14 at 15:34
Oops I overlooked that, sorry. – teeyo Nov 11 '14 at 15:35

print out object with handy way

3 Answers3