FunctionalInterfaceWithAnonymousInnerClassLambdaAndMethodReference.java

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package demo;

import java.util.Arrays;
import java.util.List;
import java.util.function.BiConsumer;
import java.util.function.Consumer;
import java.util.function.Function;
import java.util.function.Predicate;
import java.util.function.Supplier;
import java.util.stream.Collectors;

/**
 *
 * @author madhub
 */
public class FunctionalInterfaceWithAnonymousInnerClassLambdaAndMethodReference {
    
    public static void functionalInterfaceWithAnonymousInnerClassLambdaAndMethodReference() {
       final List<String> friends = Arrays.asList("Rachel Green", "Monica Geller", "Phoebe Buffay", 
               "Joey Tribbiani", " Chandler Bing", " Ross Geller ");
        // transform the list to upper case
        // using anonymous inner class
        friends.stream().map(  new Function<String, String>() {
            @Override
            public String apply(String t) {
                return t.toUpperCase();
            }
        }).forEach( new Consumer<String>() {
           @Override
           public void accept(String t) {
               System.out.println(t);
           }
        });
       // using lambda expression
       friends.stream().map( f -> f.toLowerCase())
                       .forEach(f -> System.out.println(f));
       
       // using Method reference 
       friends.stream().map(String::toUpperCase)
                        .forEach(System.out::println);
       
       
       // convert to string to upper case & join using comad
       friends.stream().map(String::toUpperCase)
               .collect(Collectors.joining());
       
       
       Runnable runnable = () -> System.out.println("Runnabe Called");
       
       Consumer<String> consumer = s -> System.out.println(s);
       consumer.accept("Hello");
       
       BiConsumer<Integer,String> biconsumer = (i,s) -> System.out.println(i+s);
       
       
       Supplier<String> supplier = () -> "Hello World";
       supplier.get();
       
       Function<String,Integer> getLen = s -> s.length();
       
       Predicate<String> pre = s -> s.startsWith("S");
       
       pre.test("Hello");
       
       
    }
    public static void main(String[] args) {
        functionalInterfaceWithAnonymousInnerClassLambdaAndMethodReference();
    }
    
}