Answer Posted / shiv prakash

Class must be final
Class must implement Comparable interface(compareTo() method)
Must override hashCode() and equals() methods
Class must implement Serializable interface

For example- all wrapper classes-Integer, Number, Character, and String

Own class
package com;

import java.io.Serializable;

public final class FinalPerson implements Serializable, Comparable<FinalPerson>{

private static final long serialVersionUID = 1L;

private final Integer personId;

private final String name;

private final String city;

private final String gender;

public FinalPerson(final Integer personId, final String name, final String city, final String gender) {
this.personId = personId;
this.name = name;
this.city = city;
this.gender = gender;
}


public Integer getPersonId() {
return personId;
}


public String getCity() {
return city;
}

public String getGender() {
return gender;
}

public String getName() {
return name;
}

@Override
public String toString() {

return "Person- name:"+this.getName()+", City:"+this.getCity()+",gender:"+this.getGender();
}


public int compareTo(FinalPerson p) {

return this.getName().compareTo(p.getName());
}

@Override
public boolean equals(Object obj) {
FinalPerson p = (FinalPerson)obj;
return this.getPersonId().equals(p.getPersonId());
}

@Override
public int hashCode() {
int hash = 7;
hash = 31* hash + this.getPersonId();
return hash;
}



}

What are the different types of garbage collectors in java?

560

---

What does I ++ mean?

619

---

What is get () in java?

580

---

What is 16 bits called?

513

---

What is difference between core java and java ee?

482

---

---

Why convert an applet to an application?

634

---

Explain exception chaining in java?

616

---

What happens when a thread cannot acquire a lock on an object in java programming?

557

---

Is this valid in java ? Can we instantiate interface in java?

558

---

What is a stringbuilder?

520

---

What is main difference between variable and constant?

540

---

Tell me the Importent classes in net package?

1590

---

What is natural ordering in java?

540

---

What is deserialization?

593

---

Can we use catch statement for checked exceptions when there is no chance of raising exception in our code?

600

---