List: forEach example: Java 8 !!!

     

      Looping List with forEach

Below example will show the demonstration of how to use forEach with List

General way to loop a List:

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Code:

---------------------------

import java.util.ArrayList;

import java.util.List;

public class Test {

       public static void main(String[] args) {

             

              List<String> items = new ArrayList<>();

              items.add("Zero");

              items.add("One");

              items.add("Two");

              items.add("Three");

              items.add("four");

              items.add("five");

              for(String item : items){

                     System.out.println(item);

              }

             

       }

}

Output:

-----------------------

Zero

One

Two

Three

four

five

 Using forEach:

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1. Looping List with forEach, Actually in Java 8, we can use lambda expression

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Code:

-----------------------------------

import java.util.ArrayList;

import java.util.List;

public class Test {

       public static void main(String[] args) {

              List<String> items = new ArrayList<>();

              items.add("Zero");

              items.add("One");

              items.add("Two");

              items.add("Three");

              items.add("four");

              items.add("five");

              // displaying result by using lambda and forEach

              items.forEach(item -> System.out.println(item));

             

       }

}

Output:

-----------------------

Zero

One

Two

Three

four

five

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2. Looping List with forEach, Actually in Java 8, we can use method reference

-----------------------------------------------------------------------------------------

Code:

-----------------------------

import java.util.ArrayList;

import java.util.List;

public class Test {

       public static void main(String[] args) {

              List<String> items = new ArrayList<>();

              items.add("Zero");

              items.add("One");

              items.add("Two");

              items.add("Three");

              items.add("four");

              items.add("five");

              // looping by using method reference

              items.forEach(System.out::println);

       }

}

Output:

----------------------

Zero
One
Two
Three
four
five

 

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3. Looping List with forEach, Actually in Java 8, we can use stream and filter

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Code: 

--------------------------

import java.util.ArrayList;

import java.util.List;

public class Test {

       public static void main(String[] args) {

              List<String> items = new ArrayList<>();

              items.add("Zero");

              items.add("One");

              items.add("Two");

              items.add("Three");

              items.add("four");

              items.add("five");

              // looping List by using Stream and filter

              items.stream().filter(s -> s.contains("B")).forEach(System.out::println);

       }

}

Output:

-------------------

One

Also check Map example with forEach