Android ArrayList compare

Question

Hi guys i got 2 ArrayList based on same class. I have to add from arraylist1 to arraylist2 non exist(s)ing rows. I tried to use contains but its always returning false. What i m doing wrong ? Ty

MyClass

public class HataKoduBean {
private String Oid;
private String Name;
private String Surname;

}

How i define Arraylists

Arraylist<MyClass> array1 = new Arraylist<>(); Arraylist<MyClass> array2 = new Arraylist<>();

How i tried to compare ?

 for (int ii = 0; ii < array1.size(); ii++) {
                            if (!array2.contains(array1.get(ii)))
                                array2.add(array1.get(ii));  
                        }

show the equals() and hashcode() implementations for the HataKoduBean class. — curob
– curob, Commented Apr 26, 2016 at 13:04

Maxim G · Accepted Answer · 2016-04-26 13:15:58Z

2

First you have to implement equals() and hashCode() in your custom class.

Consider to use Sets, so you can merge collections in one line with addAll().

edited Apr 26, 2016 at 13:15

answered Apr 26, 2016 at 12:59

Maxim G

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Comments

Monir Khlaf · Accepted Answer · 2016-04-26 13:20:10Z

0

First you have to implement equals() and hashCode() in your custom object and create loop and compare between object by using equals method like this.

implement equals and hashCode:

`@Override
    public boolean equals(Object o) {
        if (this == o)
            return true;
        if (o == null || getClass() != o.getClass()) 
           return false;
        HataKoduBean o = (HataKoduBean) o;
        return Oid != null?Oid.equals(HataKoduBean.Oid):HataKoduBean.Oid== null;
    }

    @Override
    public int hashCode() {
        return Oid != null ? Oid.hashCode() : 0;
    }`

compare Objects:

for (int ii = 0; ii < array1.size(); ii++) { if (!array2.get(ii).equals(array1.get(ii))) array2.add(array1.get(ii)); }

edited Apr 26, 2016 at 13:20

answered Apr 26, 2016 at 13:12

Monir Khlaf

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