= Java8 =
Has many improvements like added support for functional programming (anonymous functions, lambdas), added new date time API and the new stream API similar to LINQ queries in C# (map/reduce). Also has new Base64 Encoder/Decoder.

== Lambda expressions examples ==
{{{#!highlight java
/*
javac LambdaExpressionTest.java 
java -cp . LambdaExpressionTest
*/
public class LambdaExpressionTest{
    public static void main(String[] args){
        System.out.println("LambdaExpressionTest");
        // define implementation
        // (lambda parameters) -> { // lambda body };
        TestIt testIt = (stuffx) -> System.out.println("Stuff " + stuffx);
        testIt.sayStuff("Msg");
        
        // change lambda function implementation
        testIt = (stuffxx) -> {
            stuffxx = stuffxx.toUpperCase();
            System.out.println("OtherStuff " + stuffxx);            
        };
        testIt.sayStuff("Msg");
    }
    
    // lambda expressions require interfaces to define the expected parameters
    public interface TestIt{
        void sayStuff(String stuff);
    }
}
}}}

== Method reference examples ==
{{{#!highlight java
/*
Usage of :: to refer to a method. Similar in concept to function pointers/callbacks

javac MethodReferenceExample.java ASD.java 
java -cp . MethodReferenceExample   

Interface Consumer<T>
Functional interface and can therefore be used as the assignment target for a lambda expression or method reference.
*/

import java.util.ArrayList;

public class MethodReferenceExample{
    public static void main(String[] args){
        System.out.println("MethodReferenceExample");
        ArrayList<String> al = new ArrayList<String>();
        al.add("Str1");
        al.add("Str2");
        al.add("Str3");
        
        //For each string in the array list call println having as argument the item
        al.forEach(System.out::println);
        ASD dummy = new ASD();
        al.forEach(dummy::showStuff);
    }     
}
}}}
{{{#!highlight java
    public class ASD{
        public ASD(){            
        }        
        
        public void showStuff(String message){
            System.out.println("Show stuff " + message);
        }
    }
}}}

== Stream example ==
{{{#!highlight java
/*
Allows map/reduce stuff ....
javac StreamExample.java
java -cp . StreamExample
*/
import java.util.List;
import java.util.Arrays;
import java.util.stream.Stream;
import java.util.stream.Collectors;
import java.util.Optional;

public class StreamExample{
    public static void main(String[] args){
        List<Integer> list = Arrays.asList(1,5,6,9,2,5,7,8);
        
        // get stream from list collection
        Stream<Integer> stream = list.stream();
        // filters values from the list where the value is higher or equal than 5
        Stream<Integer> higherEqualThan5 = stream.filter( val -> val >=5  );
        // get list of Ints from stream
        List<Integer> list5 = higherEqualThan5.collect(Collectors.toList());        
        list5.forEach( System.out::println );
        
        stream = list.stream();
        // maps values from the list multiplying it's elements by 2
        Stream<Integer> mulBy2 = stream.map( val ->{Integer res= val*2; return res;} );
        // get list of Ints from stream
        List<Integer> listMulBy2 = mulBy2.collect(Collectors.toList());        
        listMulBy2.forEach( System.out::println );        
        
        stream = list.stream();
        // sum  (reduce) all values in the list
        Optional<Integer> reduce = stream.reduce( (a,b) -> a+b );
        if(reduce.isPresent() ){
            System.out.println(reduce.get());        
        }        
    }
}
}}}

== java time ==
{{{#!highlight java
import java.time.Instant;
import java.time.ZoneId;
import java.time.ZonedDateTime;
import java.time.format.DateTimeFormatter;
// ....
Instant instant = Instant.ofEpochMilli(datex.getTime());
DateTimeFormatter formatterDateTime = DateTimeFormatter.ofPattern("yyyyMMddHHmmss");            
ZonedDateTime dateTime = ZonedDateTime.ofInstant(instant, ZoneId.of("UTC"));
formattedDateTime = formatterDateTime.format(dateTime);
}}}

== Filter example ==
 * https://repl.it/languages/java
{{{#!highlight java
import java.util.List;
import java.util.ArrayList;
import java.util.stream.Stream;
import java.util.stream.Collectors;

class Main {
  public static void main(String[] args) {
    System.out.println("Hello world!");

    List<Integer> list = new ArrayList<Integer>();
    for(int i=1;i<10;i++){
      list.add(i);
    }
    
    Stream<Integer> s = list.stream();     
    List<Integer> result = s.filter( val -> val%2==0 ).collect(Collectors.toList());
    result.forEach(item -> System.out.println(item) );
  }
}
}}}

 * GetNumbersImpl.java  GetNumbers.java  Main.java

=== GetNumbers.java ===
{{{#!highlight java
import java.util.List;

public interface GetNumbers {
    public List<Integer> getEven(List<Integer> numbers);
}
}}}

=== GetNumbersImpl.java ===
{{{#!highlight java
import java.util.List;
import java.util.stream.Stream;
import java.util.stream.Collectors;

  public class GetNumbersImpl implements GetNumbers {
    public GetNumbersImpl(){

    }
    public List<Integer> getEven(List<Integer> numbers) {
      Stream<Integer> s = numbers.stream();
      List<Integer> result = s.filter(val -> val % 2 == 0).collect(Collectors.toList());
      return result;
    }
  }
}}}

=== Main.java ===
{{{#!highlight java
import java.util.List;
import java.util.ArrayList;
import java.util.stream.Stream;
import java.util.stream.Collectors;

class Main {

  public static void main(String[] args) {
    List<Integer> list = new ArrayList<Integer>();
    for (int i = 1; i < 10; i++) {
      list.add(i);
    }

    GetNumbers gn = new GetNumbersImpl();
    List<Integer> result =  gn.getEven(list);
    result.forEach(item -> System.out.println(item));
  }
}
}}}

=== Build and run ===
{{{#!highlight sh
yum install java-1.8.0-openjdk
yum install java-1.8.0-openjdk-devel
javac Main.java
java Main
}}}