Java : Collection Framework : HashMap (Remove)

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HashMapExample.java

import java.util.HashMap;

/*
 * Example of remove(Object key) method.
 */
public class HashMapExample
{
    public static void main( String[] args )
    {

        HashMap<Integer, String> hashMap = new HashMap<Integer, String>();

        hashMap.put(1, "Apple");
        hashMap.put(2, "Ball");
        hashMap.put(3, "Cat");

        System.out.println("hashMap : " + hashMap + "\n");

        /*
         * Removes the mapping for the specified key from this map if present.
         * 
         * Returns the previous value associated with key, or null if there was
         * no mapping for key. (A null return can also indicate that the map
         * previously associated null with key.)
         */
        
        String value = hashMap.remove(2);

        System.out.println("value : " + value);
        System.out.println("hashMap : " + hashMap);

    }
}

Output

hashMap : {1=Apple, 2=Ball, 3=Cat}

value : Ball
hashMap : {1=Apple, 3=Cat}

To Download HashMapDemoRemove Project Click the below link
https://sites.google.com/site/javaee4321/java-collections/HashMapDemoRemove.zip?attredirects=0&d=1

See also:

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