implements Serializable

The "implements Serializable" statement is used to indicate that a class in Java can be serialized, which means it can be converted into a stream of bytes that can be saved to a file or sent over a network. This allows the object to be reconstructed later, possibly on a different machine or at a different time, while preserving its state.

To implement serialization, a class needs to implement the Serializable interface, which is a marker interface with no methods. This means that the class only needs to declare that it implements Serializable, and the serialization mechanism will automatically handle the rest.

Here is an example of a class that implements Serializable:

public class Person implements Serializable {
  private String name;
  private int age;
  
  public Person(String name, int age) {
    this.name = name;
    this.age = age;
  }
  
  public String getName() {
    return name;
  }
  
  public int getAge() {
    return age;
  }
}

In this example, the Person class has two fields (name and age) and a constructor and two getter methods. By implementing Serializable, this class can now be serialized and deserialized using Java's built-in serialization mechanism.