LambdaImplementation.java

package streams;

import java.util.function.Consumer;

public class LambdaImplementation {

	public static void main(String[] args) {

		// Anonymous class, multiple instances	
		System.out.println("\nAnonymous class:");
		for (int i=0; i<5; i++) {
			Consumer<String> myPrinter1 = new Consumer<String>() {
				@Override
				public void accept(String msg) {
					System.out.println("Consuming " + msg);
				}
			};
			myPrinter1.accept(myPrinter1.toString());
		}

		
		
		// Non-capturing lambda, one instance
		System.out.println("\nNon-capturing lambda:");
		for (int i=0; i<5; i++) {
			Consumer<String> myPrinter2 =
					msg -> System.out.println("Consuming " + msg);
			
			myPrinter2.accept(myPrinter2.toString());
		}

		
		
		// Constant-capturing lambda, one instance
		System.out.println("\nConstant-capturing lambda:");
		final int secret = 42;
		for (int i=0; i<5; i++) {
			Consumer<String> myPrinter3 =
					msg -> System.out.println("Consuming " + msg + ", " + secret);
			
			myPrinter3.accept(myPrinter3.toString());
		}

		(new LambdaImplementation()).foo();
	}

	private int id = 1;
	public void foo() {
		System.out.println("\nInstance-capturing lambda:");
		
		for (int i=0; i<5; i++) {
			// this-capturing lambda, many instances!
			Consumer<String> myPrinter4 =
					msg -> System.out.println("Consuming " + msg + ", " + id);
			
			myPrinter4.accept(myPrinter4.toString());
		}
	}













}