Java 8 foreach Simple example

1.1 usually traverse a map like this

map<string, integer> items = new hashmap<> (), Items.put ("A", "ten"), Items.put ("B"), Items.put ("C", 30); Items.put ("D", +); Items.put ("E", "a"), Items.put ("F", "a"); for (map.entry<string, integer> Entry:items.entrySet ( ) {    System.out.println ("Item:" + entry.getkey () + "Count:" + entry.getvalue ());}

1.2 In Java8 you can use the foreach + lambda expression to traverse

map<string, integer> items = new hashmap<> (), Items.put ("A", "ten"), Items.put ("B"), Items.put ("C", 30); Items.put ("D", +); Items.put ("E", "a"); Items.put ("F", "a") Items.foreach ((k,v)->system.out.println ("Item:" + k + " Count: "+ V)"); Items.foreach ((k,v)->{    System.out.println ("Item:" + k + "Count:" + V);    if ("E". Equals (k)) {        System.out.println ("Hello E");}    });

2. ForEach and List

2.1 Usually traverse a list like this.

list<string> items = new arraylist<> (), Items.Add ("A"), Items.Add ("B"), Items.Add ("C"), Items.Add ("D"); Items.Add ("E"); for (String item:items) {    System.out.println (item);}

2.2 In Java8 you can use the foreach + lambda expression or the method reference (methods Reference)

list<string> items = new arraylist<> (), Items.Add ("A"), Items.Add ("B"), Items.Add ("C"), Items.Add ("D"); Items.Add ("E");//lambda//output:a,b,c,d,eitems.foreach (Item->system.out.println (item));//Output: Citems.foreach (item->{    if ("C". Equals (item)) {        System.out.println (item);    }}); /method Reference//output:a,b,c,d,eitems.foreach (system.out::p rintln);//stream and Filter//output:bitems.stream ()    . Filter (S->s.contains ("B"))    . ForEach (system.out::p rintln);

Reference Documentation:

1. Java 8 iterable ForEach JavaDoc
2. Java 8 ForEach JavaDoc

Java 8 foreach Simple example