java-basics/core-java/collections/HashMapExample.java at master · CodeForHunger/java-basics · GitHub

38 lines (29 loc) · 787 Bytes

package collections;

import java.util.HashMap;

class Key {

String key;

Key(String key) {

this.key = key;

}

@Override

public int hashCode() {

int hash = (int)key.charAt(0);

System.out.println("HashCode for Key: " + key + " = " + hash);

return hash;

}

@Override

public boolean equals(Object obj) {

return key.equals(((Key)obj).key);

}

public class HashMapExample {

public static void main(String[] args) {

HashMap map = new HashMap();

map.put(new Key("One"), 10);

map.put(new Key("Two"), 20);

map.put(new Key("Three"), 30);

System.out.println("Value for key One: " + map.get(new Key("One")));

System.out.println("Value for key Two: " + map.get(new Key("Two")));

System.out.println("Value for key Three: " + map.get(new Key("Three")));

}

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