JAVA - How To Use HashMap In Java With Iterator
Source Code:
package JavaDB_001;
import java.util.*;
public class Work {
public static void main(String[] args){
//create a HashMap
//Key is String
//value is Integer
HashMap<String,Integer> employer = new HashMap<String,Integer>();
//filling the HashMap with put method
employer.put("employer 1", 34);
employer.put("employer 2", 43);
employer.put("employer 3", 36);
employer.put("employer 5", 55);
employer.put("employer 6", 29);
employer.put("employer 7", 27);
employer.put("employer 8", 30);
employer.put("employer 9", 51);
//displaying only the key of the hashmap
System.out.println("_______Key_______");
Iterator<String> itName = employer.keySet().iterator();
while(itName.hasNext())
System.out.println(itName.next());
//displaying only the value of the hashmap
System.out.println("_______Value_______");
Iterator<Integer> itAge = employer.values().iterator();
while(itAge.hasNext())
System.out.println(itAge.next());
//displaying the key and the value of the hashmap
System.out.println("_______Key_And_Value_______");
Iterator<String> itname = employer.keySet().iterator();
while(itname.hasNext()){
String s = itname.next();
System.out.println(itname.next()+" -*- "+employer.get(s));
}
}
}
///////////////////////////OUTPUT:
_______Key_______
employer 9
employer 5
employer 6
employer 7
employer 8
employer 1
employer 2
employer 3
_______Value_______
51
55
29
27
30
34
43
36
_______Key_And_Value_______
employer 9 -*- 51
employer 5 -*- 55
employer 6 -*- 29
employer 7 -*- 27
employer 8 -*- 30
employer 1 -*- 34
employer 2 -*- 43
employer 3 -*- 36