Java 8 : Conversions

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	package com.tvidushi.DONE;
	import java.util.Arrays;
	import java.util.Comparator;
	import java.util.HashMap;
	import java.util.List;
	import java.util.Map;
	import java.util.function.Function;
	import java.util.stream.Collectors;
	public class Conversions {
	public static void convertArrayToString() {
	String[] cities = {"Delhi", "Bombay","Chennai","London","New York"};
	Arrays.stream(cities)
	.reduce((x,y)->x+"|"+y)
	.ifPresent(s->System.out.println(s));
	}
	public static void createUserListFromMap(Map<Integer, String> map) {
	List<Student> student = map
	.entrySet()
	.stream()
	.map(e -> new Student(e.getKey(), e.getValue()))
	.collect(Collectors.toList());
	student.forEach(l -> System.out.println("Id: "+ l.getId()+", Name: "+ l.getName()));
	}
	public static void createSortedUserNameListFromMap(Map<Integer, String> map) {
	List<Student> student = map.entrySet()
	.stream()
	.sorted(Comparator.comparing(e -> e.getValue()))
	.map(e -> new Student(e.getKey(), e.getValue()))
	.collect(Collectors.toList());
	student.forEach(l -> System.out.println("Id: "+ l.getId()+", Name: "+ l.getName()));
	}
	public static Map<Integer, Student> populateHashMapFromUserList(List<Student> items) {
	Map<String, Student> map = items.stream().collect(Collectors.toMap(Student::getId, Function.identity()));
	}
	public static void changeCaseOfELements(){
	List<String> alpha = Arrays.asList("surbhi", "ruchi", "anu", "sagarika");
	List upperALpha = alpha.stream().map(String::toUpperCase).collect(Collectors.toList());
	System.out.println(String.join(",",upperALpha));
	}
	public static void main(String[] args) {
	System.out.println("Converting Array to String");
	convertArrayToString();
	System.out.println("Creating list of Students by names from map");
	createUserListFromMap(new Student().createStudentDtls());
	System.out.println("Creating Sorted List of Students by names from map");
	createSortedUserNameListFromMap(new Student().createStudentDtls()) ;
	System.out.println("Changing case of Array Elements :");
	System.out.println();
	changeCaseOfELements();
	}
	}
	class Student {
	private int id;
	private String name;
	public Student(){
	}
	public Student(int id, String name) {
	this.id = id;
	this.name = name;
	}
	public int getId() {
	return id;
	}
	public String getName() {
	return name;
	}
	public Map createStudentDtls(){
	Map<Integer, String> map = new HashMap<>();
	map.put(10, "Avinash");
	map.put(12, "Brijesh");
	map.put(9, "Sujoy");
	map.put(11, "Sagar");
	return map;
	}
	public List createStudentDtlslist(){
	return Arrays.asList(new Student(10,"Avinash"),
	new Student(12,"Brijesh"),
	new Student(9,"Sujoy"),
	new Student(11,"Sagar"));
	}
	}

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