/**

* Java. Level 2. Lesson 3. Collection Framework

* Examples for lesson

*

* @author Sergey Iryupin

* @version dated Jun 11, 2018

* @see also Wrapper/Decorator (Integer, Long, Float, Double...)

*/

import java.util.List;

import java.util.ArrayList;

import java.util.Set;

import java.util.HashSet;

import java.util.TreeSet;

import java.util.Map;

import java.util.HashMap;

import java.util.TreeMap;

class J2Lesson3 {

public static void main(String[] args) {

ArrayListExample();

HashSetExample();

TreeSetExample();

HashMapExample();

TreeMapExample();

}

// @see https://docs.oracle.com/javase/8/docs/api/java/util/ArrayList.html

static void ArrayListExample() {

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

list.add("A");

list.add("B");

list.add("C");

list.add("D");

list.add("E");

System.out.println(list);

list.add(1, "A1");

System.out.println(list);

list.remove("E");

System.out.println("We'll remove " + list.get(2));

list.remove(2);

System.out.println(list);

}

// @see https://docs.oracle.com/javase/8/docs/api/java/util/HashSet.html

static void HashSetExample() {

Set<String> hs = new HashSet<>();

hs.add("Beta");

hs.add("Alpha");

hs.add("Eta");

hs.add("Gamma");

hs.add("Epsilon");

hs.add("Omega");

hs.add("Gamma");

System.out.println(hs);

}

// @see https://docs.oracle.com/javase/8/docs/api/java/util/TreeSet.html

static void TreeSetExample() {

Set<String> hs = new TreeSet<>();

hs.add("Beta");

hs.add("Alpha");

hs.add("Eta");

hs.add("Gamma");

hs.add("Epsilon");

hs.add("Omega");

hs.add("Gamma");

System.out.println(hs);

}

// @see https://docs.oracle.com/javase/8/docs/api/java/util/HashMap.html

static void HashMapExample() {

Map<String, String> hm = new HashMap<>();

hm.put("Moscow", "Russia");

hm.put("Rostov", "Russia");

hm.put("Paris", "France");

hm.put("Berlin", "Germany");

hm.put("Oslo", "Norway");

Set<Map.Entry<String, String>> set = hm.entrySet();

for (Map.Entry<String, String> o : set)

System.out.println(o.getKey() + ": " + o.getValue());

System.out.println(hm);

System.out.println(hm.get("Paris"));

}

// @see https://docs.oracle.com/javase/8/docs/api/java/util/TreeMap.html

static void TreeMapExample() {

Map<String, String> tm = new TreeMap<>();

tm.put("Moscow", "Russia");

tm.put("Paris", "France");

tm.put("Berlin", "Germany");

tm.put("Oslo", "Norway");

Set<Map.Entry<String, String>> set = tm.entrySet();

for(Map.Entry<String, String> o : set)

System.out.println(o.getKey() + ": " + o.getValue());

System.out.println(tm);

}

}