Builder design pattern ?

 This is a type of creational design pattern where user can create object without specifying all the parameter of the constructor to build the object using a builder .

Advantage:

1.No need to specify all the parameter into constructor .

2.No need to maintain parameter sequence in constructor .

3.User can create object by their need .

Ex:

PC class:

public class PC {

private String ram;

private String processor;

private String hdd;

private String motherBoard;

public PC(String ram, String processor, String hdd, String motherBoard) {

super();

this.ram = ram;

this.processor = processor;

this.hdd = hdd;

this.motherBoard = motherBoard;

}

@Override

public String toString() {

return "PC [ram=" + ram + ", processor=" + processor + ", hdd=" + hdd + ", motherBoard=" + motherBoard + "]";

}

}

Builder class:

package builderDesignPatternImplementation;

public class PcBuilder {

private String ram;

private String processor;

private String hdd;

private String motherBoard;

public PcBuilder setRam(String ram) {

this.ram = ram;

return this;

}

public PcBuilder setProcessor(String processor) {

this.processor = processor;

return this;

}

public PcBuilder setHdd(String hdd) {

this.hdd = hdd;

return this;

}

public PcBuilder setMotherBoard(String motherBoard) {

this.motherBoard = motherBoard;

return this;

}

public PC getPC() {

return new PC(ram, processor, hdd, motherBoard);

}

}

Main App:

public class MainApp {

public static void main(String[] args) {

PcBuilder builder = new PcBuilder();

PC pc = builder.setProcessor("core i7").setHdd("samsung").getPC();

System.out.println(pc.toString());

}

}