Arraylist output getting overriden [duplicate]

Question

The data which was previously stored in an array list , is getting replaced by updated data.

code is shown below

public class Telivision {

    private String tvBrand;
    private Double tvCost;
    private Integer tvDimension;
    private String tvScreen;
    public String getTvBrand() {
        return tvBrand;
    }
    public void setTvBrand(String tvBrand) {
        this.tvBrand = tvBrand;
    }
    public Double getTvCost() {

        return tvCost;
    }
    public void setTvCost(String brand) {
        if(this.tvBrand.equalsIgnoreCase("Samsung")){
            this.tvCost = 100*1.5;
        }else if(this.tvBrand.equalsIgnoreCase("Sony")){
            this.tvCost = 100*2.0;
        }
    }
    public Integer getTvDimension() {
        return tvDimension;
    }
    public void setTvDimension(Integer tvDimension) {
        this.tvDimension = tvDimension;
    }
    public String getTvScreen() {
        return tvScreen;
    }
    public void setTvScreen(String tvScreen) {
        this.tvScreen = tvScreen;
    }
    @Override
    public String toString() {
        return "Telivision [tvBrand=" + tvBrand + ", tvCost=" + tvCost + ", tvDimension=" + tvDimension + ", tvScreen="
                + tvScreen + "]";
    }

TESTER IS AS SHOWN BELOW

public class TelivisionTester {

    public static void main(String[] args) {

        Telivision telivision = new Telivision();
        ArrayList<Telivision> telList = new ArrayList<Telivision>();        
        telivision.setTvBrand("SAMSUNG");
        telivision.setTvDimension(40);
        telivision.setTvScreen("Led");
        telivision.setTvCost("Samsung");
        telList.add(telivision);
        System.out.println(telList);
        System.out.println(telivision.getTvBrand()+"Cost is "+telivision.getTvCost());

        telivision.setTvBrand("Sony");
        telivision.setTvDimension(36);
        telivision.setTvScreen("Led");
        telivision.setTvCost("Sony");
        telList.add(telivision);
        System.out.println(telList);
        System.out.println(telivision.getTvBrand()+"Cost is "+telivision.getTvCost());
    }

the output which is expected is as shown below

[Telivision [tvBrand=SAMSUNG, tvCost=150.0, tvDimension=40, tvScreen=Led],
Telivision [tvBrand=Sony, tvCost=200.0, tvDimension=36, tvScreen=Led]]

but the output observed is as shown below

[Telivision [tvBrand=Sony, tvCost=200.0, tvDimension=36, tvScreen=Led], 
Telivision [tvBrand=Sony, tvCost=200.0, tvDimension=36, tvScreen=Led]]

kindly let me know what mistake i am doing in this code

You are not creating a second Telivision. You keep using the first (and only) instance. — f1sh
– f1sh, Commented Aug 5, 2019 at 18:47
Yeah as f1sh said you are only making 1 television. Say you have 1 TV in real life and modify it to be different, you still have only 1 TV. Call telivision = new Telivision(); again in your test code before the Sony brand. — Nexevis
– Nexevis, Commented Aug 5, 2019 at 18:50
So in the above code whenever i need to update a new value , i need to create a new object and then update it. — Anand Ramamurthy
– Anand Ramamurthy, Commented Aug 5, 2019 at 18:50
instanciate 2 Telivisions. Telivision samsung = new Telivision(); for Samsung and Telivision sony = new Telivision(); for Sony — suntzu
– suntzu, Commented Aug 5, 2019 at 18:53

stoneg64 · Accepted Answer · 2019-08-05 18:54:30Z

You're list is not being overwritten. You are are adding the same instance of the class twice instead of creating a new one with the new attributes. Because the original istance changed you get the same attributes for both entries in the list. Create a new instance of the object for each Television you add to the list.

   public static void main(String[] args) {

    Telivision telivision = new Telivision();
    ArrayList<Telivision> telList = new ArrayList<Telivision>();        
    telivision.setTvBrand("SAMSUNG");
    telivision.setTvDimension(40);
    telivision.setTvScreen("Led");
    telivision.setTvCost("Samsung");
    telList.add(telivision);
    System.out.println(telList);
    System.out.println(telivision.getTvBrand()+"Cost is "+telivision.getTvCost());
    Telivision secondTelivision = new Telivision();
    secondTelivision.setTvBrand("Sony");
    secondTelivision.setTvDimension(36);
    secondTelivision.setTvScreen("Led");
    secondTelivision.setTvCost("Sony");
    telList.add(secondTelivision);
    System.out.println(telList);


}

burgerdude · Accepted Answer · 2019-08-05 19:01:46Z

You forgot to declare a second Telivision to separate the two.

public class TelivisionTester {
public static void main(String[] args) {

    Telivision telivision = new Telivision();
    ArrayList<Telivision> telList = new ArrayList<Telivision>();        
    telivision.setTvBrand("SAMSUNG");
    telivision.setTvDimension(40);
    telivision.setTvScreen("Led");
    telivision.setTvCost("Samsung");
    telList.add(telivision);
    System.out.println(telList);
    System.out.println(telivision.getTvBrand()+"Cost is "+telivision.getTvCost());

    Telivision television2 = new Television();
    telivision2.setTvBrand("Sony");
    telivision2.setTvDimension(36);
    telivision2.setTvScreen("Led");
    telivision2.setTvCost("Sony");
    telList.add(telivision2);
    System.out.println(telList);
    System.out.println(telivision2.getTvBrand()+"Cost is "+telivision2.getTvCost());
    //telList.addAll(telList);

    //System.out.println(telList);

}
}

Also “Telivision” is actually spelled Television

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