Java - Iteration of ArrayList

Question

I have a Class A

CLASS A

public ClassA {

ArrayList<ClassB> objB= new ArrayList<ClassB>();

 //getter and setter of objB

}

CLASS B

public classB {

int x;
int y;

private List<ClassC> objC= null;

//getter and setter of x,y and objC

}

CLASS C

public classC {

int a;
int b;

//getters and setters of a,b

}

I am storing a resultset in objB inside class A. I am trying to iterate objB in my service class.

public Class serviceImpl{

ClassA objA = new ClassA();

//here I need to get the values of variable x,y,a,b

}

Your question doesn't make much sense. Please state more clearly what you want... — willeM_ Van Onsem
– willeM_ Van Onsem, Commented Jul 10, 2014 at 21:20

PbxMan · Accepted Answer · 2014-07-10 21:53:14Z

2

You could use and enhanced for-loop.

Don't use classB instead of B in the generics. You got it right during the second edition. Perhaps this can help you.

    ArrayList<B> classB = new ArrayList<B>();
public static void main(String[] args) {
    // instantiate the objects
    A myClassA = new A();
    B myClassB = new B();
    C myClassC1 = new C();
    C myClassC2 = new C();
    // set the values
    myClassC1.setA(1);
    myClassC1.setB(10);
    myClassC2.setA(2);
    myClassC2.setB(20);
    myClassB.setX(3);
    myClassB.setY(30);
    // create the lists
    List<C> myListC = new ArrayList<C>();
    myListC.add(myClassC1);
    myListC.add(myClassC2);
    // set the lists
    myClassB.setObjC(myListC);
    myClassA.classB.add(myClassB);// better use a getter/setter
    // iterate the list
    for (B auxClassB : myClassA.classB) {
        System.out.println("X:" + auxClassB.getX() + " Y:"
                + auxClassB.getY());
        for (C auxClassC : auxClassB.getObjC()) {
            System.out.println("A: "+  auxClassC.a + " B: "+ auxClassC.getB());
        }
    }
}

Console output

X:3 Y:30
A: 1 B: 10
A: 2 B: 20

Good luck

edited Jul 10, 2014 at 21:53

answered Jul 10, 2014 at 21:21

PbxMan

7,6331 gold badge40 silver badges40 bronze badges

Sign up to request clarification or add additional context in comments.

5 Comments

The Guy with The Hat Over a year ago

Before anyone asks, no this is not a link-only answer.

Mikkel Løkke Over a year ago

Today I learned that in Java the foreach iterator is called an "enhanced for loop", even though it is less useful than regular for loops.

PbxMan Over a year ago

I know that, i'm just wating the question to develop

Namita Over a year ago

Hi @PbxMan, I have updated my question, hope it makes more sense now.

Namita Over a year ago

aah, i got it, thanks for making me understand. Appreciate your help :). thank you so much :)

Jashaszun · Accepted Answer · 2014-07-10 21:22:33Z

0

Somewhere in class A:

for (ClassB b : classB)
{
    // whatever you want with b, which is of type ClassB
}

answered Jul 10, 2014 at 21:22

Jashaszun

9,2503 gold badges31 silver badges58 bronze badges

1 Comment

Namita Over a year ago

Class A is just a value object class which contains the arraylist object of class B and getters and setters. I need to get the content of Class B and C by creating object of class A in different class.

Collectives™ on Stack Overflow

Java - Iteration of ArrayList

2 Answers 2

5 Comments

1 Comment

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

5 Comments

1 Comment

Your Answer

Sign up or log in

Post as a guest

Linked

Related