Let's Relax! Builder Pattern Example and Lombok API

Hi All,

Thanks again for reading my comments over internet.

I am trying to help java developers to know more about implementations and configurations using Java or JBoss Midleware technologies.

Now i would like to show a simple implementation pattern: Builder.
So, let's see the example:

1 - Simple Person class

/**
 * Person simple class information
 *
 * @author alvesfred
 *
 */
public class SimplePerson implements Serializable {

    /**
     * serial
     */
    private static final long serialVersionUID = -978731152684129660L;

    private String name;
    private int age;
    private boolean male;
    private boolean married;

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }

    public boolean isMale() {
        return male;
    }

    public void setMale(boolean male) {
        this.male = male;
    }
   
    public boolean isMarried() {
        return married;
    }
   
    public void setMarried(boolean married) {
        this.married = married;
    }
}

2 - Builder Pattern

/**
 * Builder pattern
 *
 * @author alvesfred
 *
 */
public abstract class Builder<T> {
    /**
     * Build
     *
     * @return
     */
    public abstract T build();
}
 
/**
 * Builder pattern class
 *
 * @author alvesfred
 *
 */
public class Person {

    private final String name;
    private final int age;
    private final boolean male;
    private final boolean married;

    public Person(PersonBuilder pfb) {
        this.name    = pfb.name;
        this.age     = pfb.age;
        this.male    = pfb.male;
        this.married = pfb.married;
    }

    public String getName() {
        return name;
    }

    public int getAge() {
        return age;
    }

    public boolean isMale() {
        return male;
    }

    public boolean isMarried() {
        return married;
    }

    /**
     * Builder class sample
     *
     * @author alvesfred
     *
     */
    public static class PersonBuilder extends Builder<Person> {
        private final String name;
        private int age;
        private boolean male;
        private boolean married;

        public PersonBuilder(String name) {
            this.name = name;
        }

        public PersonBuilder defineAge(int age) {
            this.age = age;
            return this;
        }

        public PersonBuilder defineMale(boolean male) {
            this.male = male;
            return this;
        }

        public PersonBuilder defineMarried(boolean married) {
            this.married = married;
            return this;
        }

        public Person build() {
            return new Person(this);
        }
    }

    @Override
    public String toString() {
        return "[PERSON] "        + name
                + " - [Age] "     + age
                + " - [Male?] "   + male
                + " - [Married] " + married;
    }

    /**
     * Main
     *
     * @param args
     */
    public static void main(String[] args) {
        Person p = new PersonBuilder("Fred")
            .defineAge(38)
            .defineMale(true)
            .defineMarried(true)
            .build();

        System.out.println(p);
    }
}

A few months ago i see this important API, and i like it so much!
Lombok API is very interesting...have fun!

https://projectlombok.org/

[IMHO] for @Data annotation using lombok, I just recommend override equals and hashCode methods to use HashCodeBuilder and EqualsBuilder (Apache Commons).


Thanks a lot and see you next time!

"Move to Canada/Vancouver - it is my dream! Java/JEE/Middleware development is my work and i love it so much!"