How do I compare two objects in Java?

How do I compare two objects in Java?

In Java, you can compare two objects using the equals() method. This method checks if two references point to the same object or if they are logically equivalent.

What if I want to compare objects of a custom class?

For custom classes, you should override the equals() method to define what it means for two instances to be equal. You may also want to override hashCode().

Can you show me an example of overriding equals?

Sure! Here's a simple example:

@Override
public boolean equals(Object obj) {
    if (this == obj) return true;
    if (obj == null || getClass() != obj.getClass()) return false;
    MyClass myClass = (MyClass) obj;
    return this.id == myClass.id;
}

What about comparing objects in a list?

You can use the contains() method of the List interface, which internally uses the equals() method to check for equality.