Java Builder Design Pattern Example

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public class JavaBuilderDesignPattern {

	public static void main(String args[]) {

		// Create the object using builder pattern

		Cake whiteCakeNonVeg = new Cake.Builder().sugar(1).
                butter(0.5).eggs(2).vanila(2).bakingpowder(0.75).milk(0.5)
				.build();

		Cake whiteCakeVeg = new Cake.Builder().sugar(1).
                butter(0.5).vanila(2).bakingpowder(1.75).milk(0.5).flour(2)
		.build();

		System.out.println(whiteCakeNonVeg);
		System.out.println(whiteCakeVeg);
	}

}

class Cake {
	private final double milk;
	private final double sugar;
	private final double butter;
	private final int eggs;
	private final double bakingpowder;
	private final int vanila;
	private final double flour;

	// constructor should be private to enforce object creation through builder
	private Cake(Builder builder) {
		this.milk = builder.milk;
		this.sugar = builder.sugar;
		this.butter = builder.butter;
		this.eggs = builder.eggs;
		this.bakingpowder = builder.bakingpowder;
		this.vanila = builder.vanila;
		this.flour = builder.flour;

	}

	public static class Builder {
		private double milk;
		private double sugar;
		private double butter;
		private int eggs;
		private double bakingpowder;
		private int vanila;
		private double flour;

		public Builder milk(double cup) {
			this.milk = cup;
			return this;
		}

		public Builder sugar(double cup) {
			this.sugar = cup;
			return this;
		}

		public Builder butter(double cup) {
			this.butter = cup;
			return this;
		}

		public Builder eggs(int number) {
			this.eggs = number;
			return this;
		}

		public Builder vanila(int spoon) {
			this.vanila = spoon;
			return this;
		}

		public Builder bakingpowder(double spoon) {
			this.bakingpowder = spoon;
			return this;
		}

		public Builder flour(double cup) {
			this.flour = cup;
			return this;
		}

		// return fully build object
		public Cake build() {
			return new Cake(this);
		}
	}

	@Override
	public String toString() {
		return "Cake { milk=" + milk + "sugar=" + sugar + ", butter=" + butter + ", eggs=" + eggs + ", vanila=" + vanila
				+ ", bakingpowder=" + bakingpowder + ", flour=" + flour + '}';

	}

}
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