TestMap.java

import java.util.*;<br />public class TestMap {<br />public static void main(String[] args) {<br />Map m1 = new HashMap();<br />Map m2 = new TreeMap();<br />m1.put("one", new Integer(1));<br />m1.put("two", new Integer(2));<br />m1.put("three", new Integer(3));<br />m2.put('A', new Integer(1));<br />m2.put('B', new Integer(2));<br />System.out.println(m1.size());<br />System.out.println(m1.containsKey("one"));<br />System.out.println(m2.containsValue(new Integer(1)));<br />if(m1.containsKey("two")) {<br />int i = ((Integer)m1.get("two")).intValue();<br />System.out.println(i);<br />}<br />Map m3 = new HashMap(m1);<br />m3.putAll(m2);<br />System.out.println(m3);<br />}<br />}<br />