If objects of same class are identical

I have a java class which has 15 data members.
I have 2 objects of that class.
I want to check if the 2 objects are identical or not.
Comparing each data member is time consuming.
Is there a better approach

If you mean 'it takes a lot of CPU time' - no it doesn't. It just compares a whole bunch of bits and that's.. literally exactly what you want to do, so, just do that: Compare each and every field.

If you mean 'that takes a lot of writing', IDEs can autogenerate that stuff, though then you have to look at it, maintain it, get in trouble when you add a field and forget to update those buckets of boilerplate. So, you could instead use Project Lombok's @Value or @EqualsAndHashCode feature.

You can override the equals method in order to write your own custom comparator between two instances of the same type. Refer to this Spring documentation for more info. Also, refer to rzwitserloot's answer for simply using Lombok annotations to have this equals method automatically generated for you.

public class MyClass {
  private String dataField1;
  private String dataField2;
  // declare remaining 13 instance level data fields

  @Override
  public boolean equals(Object o) {
    if (this == o) return true;
	if (o == null || getClass() != o.getClass()) return false;
	MyClass that = (MyClass) o;

	return dataField1.equals(that.dataField1) &&
	      dataField2.equals(that.dataField2);
    // Compare remaining 13 instance fields
  }
}

Then you can compare the two instances by using this equals method:

MyClass m1 = new MyClass();
MyClass m2 = new MyClass();

System.out.println(m1.equals(m2));

From your comment

> Suppose i have 1000 objects with unique id stored in one table.same
> 1000 objects comes again via some scheduler and it checks whether the
> values have been changed or not.

I understand that each object will be compared exactly once against its stored version. In this use case, there's no better way than comparing the fields.

An idea that comes to one's mind is to use hash codes derived from the field values. If hash codes are different, the fields must be different too. And that is done by just one integer comparison. If the hash codes are identical, you still have to check the field values, as there can be collisions: different objects resulting in the same hash code.

But I suppose, in any step quite a big percentage of your objects have not changed their values. So, introducing hash codes can only improve the "changed" cases, and computing one hash codes will probably take longer than comparing two objects.