JavaBean class in Java

A JavaBean is a specially constructed Java class written in the Java and coded according to the JavaBeans API specifications.

Following are the unique characteristics that distinguish a JavaBean from other Java classes −

• It provides a default, no-argument constructor.

• It should be serializable and that which can implement the Serializable interface.

• It may have a number of properties which can be read or written.

• It may have a number of "getter" and "setter" methods for the properties.

JavaBeans Properties

A JavaBean property is a named attribute that can be accessed by the user of the object. The attribute can be of any Java data type, including the classes that you define.

A JavaBean property may be read, write, read only, or write only. JavaBean properties are accessed through two methods in the JavaBean's implementation class −

A read-only attribute will have only a getPropertyName() method, and a write-only attribute will have only a setPropertyName() method.

Example

 Live Demo

class StudentsBean implements java.io.Serializable {
   private String firstName = null;
   private String lastName = null;
   private int age = 0;
   public StudentsBean() {
   }
   public String getFirstName() {
      return firstName;
   }
   public String getLastName() {
      return lastName;
   }
   public int getAge() {
      return age;
   }
   public void setFirstName(String firstName) {
      this.firstName = firstName;
   }
   public void setLastName(String lastName) {
      this.lastName = lastName;
   }
   public void setAge(Integer age) {
      this.age = age;
   }
}
public class Tester {
   public static void main(String[] args) {
      StudentsBean bean = new StudentsBean();
      bean.setFirstName("Mahesh");
      System.out.println(bean.getFirstName());
   }
}

Output

Mahesh