Java 8 Notes Pics

Note: we can also use Collections.sort() also to sort objects.

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<Integer> Stream<Integer> java.util.stream.Stream.map(Function<? super Integer, ? extends Integer> mapper)

*IN SINGLE LINE*

List lt = al.stream().map(d->d*2).collect(Collectors.toList());

System.out.println("List: "+lt);

----------code

package com.test;

import java.util.ArrayList;

import java.util.List;

import java.util.stream.Collectors;

import java.util.stream.Stream;

public class StreamExample2 {

public static void main(String[] args)

{

ArrayList<Integer> al = new ArrayList<Integer>();

al.add(45);

al.add(55);

al.add(65);

al.add(75);

al.add(85);

List lt = al.stream().map(d->d*2).collect(Collectors.toList());

System.out.println("List: "+lt);

Stream<Integer> stream = al.stream();

Stream<Integer> s2 = stream.map(x->x*2);

// s2.forEach(x->System.out.println(x));

List<Integer>li = s2.collect(Collectors.toList());

System.out.println(li);

}

}

 

Output:

List: [90, 110, 130, 150, 170]

[90, 110, 130, 150, 170]

 

 

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Stream<String> java.util.stream.Stream.filter(Predicate<? super String> predicate)

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Showing forEach() of Java 8 

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Commonly used Funtional Interfaces of Java 8