JavaBean

A JavaBean is a Java class that follows the JavaBeans specification: a public no-argument constructor, private fields, public getter/setter methods following a naming pattern, and (traditionally) implementation of Serializable. Reflection-based frameworks — Spring, JPA, Jackson, older GUI builders — rely on these conventions.

Example

import java.io.Serializable;

public class Person implements Serializable {
    private String name;
    private int age;

    public Person() {}  // required no-arg constructor

    public String getName()        { return name; }
    public void   setName(String n){ this.name = n; }
    public int    getAge()         { return age; }
    public void   setAge(int a)    { this.age = a; }
}

Property naming convention

• For a property age: getter is getAge(), setter is setAge(int).
• For a boolean property active: getter can be isActive() instead of getActive().
• Naming is strict — frameworks discover properties by matching these patterns via reflection.

JavaBean vs POJO vs record

• POJO — any simple Java class with no special constraints.
• JavaBean — a POJO that also follows the JavaBeans naming convention.
• Record — the modern replacement for immutable data carriers (Java 16+). Records are not strictly JavaBeans (accessors are age(), not getAge()) but most frameworks now support both patterns.