Dictionary get(Object) in Java

get(Object): This method is available in java.util.Dictionary class of Java.

Syntax:

Integer java.util.Dictionary.get(Object key)

This method takes one argument of type Object as its parameter. This method returns the value to which the key is mapped in this dictionary.

Parameters: One parameter is required for this method.

key: a key in this dictionary. null if the key is not mapped to any value in this dictionary.

Returns: the value to which the key is mapped in this dictionary.

Throws:

1. NullPointerException - if the key is null.

Approach 1: When no exception

Java

import java.util.Dictionary;
import java.util.Hashtable;

public class Dictionaryeget {
    public static void main(String[] args) {

        Dictionary<String, Integer> dictionary = 
                         new Hashtable<String, Integer>();

        dictionary.put("Hello", 10);
        dictionary.put("Java", 4);
        dictionary.put("C++", 17);

        System.out.println(dictionary.get("Hello"));

    }
}

Output:

10

Approach 2: NullPointerException 

Java

import java.util.Dictionary;
import java.util.Hashtable;

public class Dictionaryeget {
    public static void main(String[] args) {

        Dictionary<String, Integer> dictionary = 
                   new Hashtable<String, Integer>();

        dictionary.put("Hello", 10);
        dictionary.put("Java", 4);
        dictionary.put("C++", 17);

        System.out.println(dictionary.get(null));

    }
}

Output:

Exception in thread "main" java.lang.NullPointerException: Cannot invoke "Object.hashCode()" because "key" is null
	at java.base/java.util.Hashtable.get(Hashtable.java:381)