ConcurrentSkipListMap example to make map unmodifiable in java

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ConcurrentSkipListMap - making map unmodifiable using Collections.unmodifiableMap in java

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import java.util.Collections; import java.util.Map; import java.util.concurrent.ConcurrentSkipListMap; /** Copyright (c), AnkitMittal JavaMadeSoEasy.com */ public class ConcurrentSkipListMapUnmodifiableExample {    public static void main(String args[]){                     Map<Integer,String> concurrentSkipListMap=new ConcurrentSkipListMap<Integer,String>();              concurrentSkipListMap.put(11, "ankit");           concurrentSkipListMap.put(21, "mittal");           concurrentSkipListMap.put(31, "javaMadeSoEasy");                     //getting unmodifiable ConcurrentSkipListMap           Map<Integer,String> unmodifiableMap = Collections.unmodifiableMap(concurrentSkipListMap);              /*           * Now any attempt to modify map will throw java.lang.UnsupportedOperationException           */           unmodifiableMap.put(41,"java");    } } /*OUTPUT Exception in thread "main" java.lang.UnsupportedOperationException    at java.util.Collections$UnmodifiableMap.put(Unknown Source)    at concurrentSkipListMap_unmodifiable.concurrentSkipListMapTest.main(concurrentSkipListMapTest.java:24) */

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Labels: Collection programs Core Java