Question

This is an update of the same question, which is partly solved.

Java – Object properties does not differ

int size = 0;
int new = 10;
int default = 100;

ClassList filterList = new ClassList();
filterList.setSize(size);
filterList.setNew(new);
filterList.setDefault(default);

// Now i am creating another instance of the ClassList.

ClassList newList = ClassList(); 

Its strange that my newList has values of size, new and default, but with values as 0, 0 and 0 I tried to check whether the instances are same or not.

if(filterList .equals(newList)){
    Log.d("Is it equal","True");
    } else {
    Log.d("Its Not equal","false");
}

I got it false.

My POJO class is plain simple with getters and setters.

public class ClassList{

    private int size;
    private int new;
    private int default;

    public int getPageSize() {
        return size;
    }
    public void setPageSize(int size) {
        this.size = size;
    }
}

Answer 1

Default value for int is 0 that is why size, new and default has values 0, 0 and 0 on newly created instance

Default equals comparison happens on == that is reference equality.
You will need to override equals and hashcode

From Java doc of Object#equals

The equals method for class Object implements the most discriminating possible equivalence relation on objects; that is, for any non-null reference values x and y, this method returns true if and only if x and y refer to the same object (x == y has the value true).

Note that it is generally necessary to override the hashCode method whenever this method is overridden, so as to maintain the general contract for the hashCode method, which states that equal objects must have equal hash codes.

Sample Implementaion :

public static class ClassList {

    private int size;
    private int newValue;
    private int defaultValue;

    public int getPageSize() {
        return size;
    }
    public void setPageSize(int size) {
        this.size = size;
    }

    @Override
    public boolean equals(Object obj) {
        if (obj == null)
            return false;
        if (!(obj instanceof ClassList))
            return false;
        ClassList c = (ClassList) obj;

        return this.size == c.size && this.newValue == c.newValue
                && this.defaultValue == c.defaultValue;
    }

    @Override
    public int hashCode() {
        return Integer.valueOf(size).hashCode()
                + Integer.valueOf(newValue).hashCode()
                + Integer.valueOf(defaultValue).hashCode();
    }
}

Note: new and default are reserved keywords in java. You can not define variable names for reserve keywords.

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References:

• equals()
• hashcode()
• toString()