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Java: Associate the specified value with the specified key in a HashMap


Write a Java program to associate the specified value with the specified key in a HashMap.

Sample Solution:

Java Code:

import java.util.*;  
public class Example1 {  
  public static void main(String args[]) {  
  HashMap<Integer,String> hash_map= new HashMap<Integer,String>();  
  hash_map.put(1, "Red");
  hash_map.put(2, "Green");
  hash_map.put(3, "Black");
  hash_map.put(4, "White");
  hash_map.put(5, "Blue");
  for(Map.Entry x:hash_map.entrySet()){  
   System.out.println(x.getKey()+" "+x.getValue());  
  }  
 }  
}

Sample Output:

1 Red                                                                  
2 Green                                                                
3 Black                                                                
4 White                                                                
5 Blue

For more Practice: Solve these Related Problems:

  • Write a Java program to insert a key-value pair into a HashMap and then update the value if the key already exists.
  • Write a Java program to merge two HashMaps such that if keys collide, the values are concatenated into a single string.
  • Write a Java program to create a HashMap, add key-value pairs, and then remove a key only if it is mapped to a specific value.
  • Write a Java program to implement a method that adds a key-value pair to a HashMap and returns the previous value associated with the key.

Java Code Editor:

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