The java.util.Dictionary class is the abstract parent of any class, for instance, Hashtable, which maps keys to values. Here each key and esteem will be dealt with as a protest and key partners with one esteem. Taking after is the linguistic synatx of java.util.Dictionary class. [java] public abstract class Dictionary<K,V> extends Object [/java] The java.util.Dictionary class will have only single constructor that is Dictionary() and methods will be inherited by java.util.Object class.

Following are the methods of java.util Dictionary Class.

Following is the syntax declaration of the method. [java]public abstract Enumeration<V> elements()[/java] DemoDictionary.java [java] package com.SPlessons; import java.util.*; public class DemoDictionary { public static void main(String[] args) { // create a new hashtable Dictionary d = new Hashtable(); // add 2 elements d.put(5, "SP"); d.put(6, "SPLessons" + "Tutorial"); System.out.println("\"5\" is " + d.get(5)); System.out.println("\"6\" is " + d.get(6)); // generates a series of elements, one at a time for (Enumeration e = d.elements(); e.hasMoreElements();) { System.out.println(e.nextElement()); } } } [/java] The Hashtable was a piece of the first java.util and is a solid usage of a Dictionary. Output: Now compile the code result will be as follows. [java] "5" is SP "6" is SPLessonsTutorial SPLessonsTutorial SP [/java]

Following is the syntax declaration of the method. [java]public abstract V get(Object key)[/java] DemoDictionary.java [java] package com.SPlessons; import java.util.*; public class DemoDictionary { public static void main(String[] args) { // create a new hashtable Dictionary dict = new Hashtable(); // add elements in the hashtable dict.put("4", "SP"); dict.put("5", "Lesson"); dict.put("6", "SPLesson"); // returns the elements associated with the key System.out.println(dict.get("6")); } } [/java] In the above code, the given value has been returned. Output: Now compile the code result will be as follows. [java] SPLesson [/java]

Following is the syntax declaration of the method. [java]public abstract Enumeration<K> keys()[/java] DemoDictionary.java [java]package com.SPlessons; import java.util.*; public class DemoDictionary { public static void main(String[] args) { // create a new hashtable Dictionary d = new Hashtable(); // add some elements d.put("4", "SP"); d.put("5", "Lesson"); d.put("6", "SPLessons"); // return an enumeration of the keys from this dictionary. for (Enumeration e = d.keys(); e.hasMoreElements();) { System.out.println(e.nextElement()); } } } [/java] Following is the syntax for Enumeration.hasMoreElements() method. [java]boolean hasMoreElements()[/java] Following is the figure to explain the functionality of put() method. Output: Now compile the code result will be as follows. [java] 6 5 4 [/java]

Following is the syntax declaration of the method. [java]public abstract V put(K key,V value)[/java] DemoDictionary.java [java] package com.SPlessons; import java.util.*; public class DemoDictionary { public static void main(String[] args) { // create a new hasthtable Dictionary d = new Hashtable(); // put some elements d.put("4", "SP"); d.put("5", "Lesson"); d.put("6", "SPLessons"); // print how many times put was called System.out.println("Number of times put was called:" + d.size()); } } [/java] Output: Now compile the code result will be as follows. [java]Number of times put was called:3 [/java]

Following is the syntax declaration of the method. [java]public abstract V remove(Object key)[/java] DemoDictionary.java [java] package com.SPlessons; import java.util.*; public class DemoDictionary { public static void main(String[] args) { // create a new hasthtable Dictionary d = new Hashtable(); // put some elements d.put("4", "SP"); d.put("5", "Lesson"); d.put("6", "SPLessons"); // remove one element System.out.println(d.get("5")); System.out.println(d.remove("5") + " has been removed"); System.out.println(d.get("5")); } } [/java] In the above example, the developer selected the value 5 to remove. Output: Now compile the code result will be as follows. [java] Lesson Lesson has been removed null[/java]

Following is the syntax declaration of the method. [java]public abstract int size()[/java] DemoDictionary.java [java]package com.SPlessons; import java.util.*; public class DemoDictionary { public static void main(String[] args) { // create a new hasthtable Dictionary d = new Hashtable(); // put some elements d.put("4", "SP"); d.put("5", "Lesson"); d.put("6", "SPLessons"); System.out.println("Size of dictionary:" + d.size());; } } [/java] Output: Now compile the code result will be as follows. [java]Size of dictionary:3[/java]

Following is the syntax declaration of the method. [java]public abstract boolean isEmpty()[/java] DemoDictionary.java [java]package com.SPlessons; import java.util.*; public class DemoDictionary { public static void main(String[] args) { // create a new hasthtable Dictionary d = new Hashtable(); // put some elements d.put("4", "SP"); d.put("5", "Lesson"); d.put("6", "SPLessons"); // return true if this dictionary maps no keys to value. boolean b = d.isEmpty(); System.out.println("Dictionary is empty:" + b); } } [/java] The java.util.Dictionary.isEmpty() method returns true if this dictionary has no keys to values otherwise returns false. Output: Now compile the code result will be as follows. [java]Dictionary is empty:false[/java]

• Java.util Dictionary - The java.util.Dictionary class will hire the methods from java.util.Object class.
• Java.util Dictionary - The Dictionary() is the single constructor of the java.util.Dictionary class
• The keys() method is used to return an enumeration of the keys.