The isEmpty() method of Dictionary Class checks whether this dictionary has any key-value mappings or not. The function returns TRUE only if there is no entry in this dictionary.
Syntax:
public abstract boolean isEmpty()
Return Value: The function returns TRUE if the dictionary is empty and FALSE otherwise.
Exception: The function throws no exception.
Below programs illustrate the use of Dictionary.isEmpty() method:
Program 1:
// Java Program to illustrate// Dictionary.isEmpty() method  import java.util.*;  class GFG {    public static void main(String[] args)    {          // Create a new hashtable        Dictionary<Integer, String>            d = new Hashtable<Integer, String>();          // Insert elements in the hashtable        d.put(1, "Geeks");        d.put(2, "for");        d.put(3, "Geeks");          // Print the Dictionary        System.out.println("\nDictionary: " + d);          // check if this dictionary is empty        // using isEmpty() method        if (d.isEmpty()) {            System.out.println("Dictionary "                               + "is empty");        }        else            System.out.println("Dictionary "                               + "is not empty");    }} |
Output:
Dictionary: {3=Geeks, 2=for, 1=Geeks}
Dictionary is not empty
Program 2:
// Java Program to illustrate// Dictionary.isEmpty() method  import java.util.*;  class GFG {    public static void main(String[] args)    {          // Create a new hashtable        Dictionary<String, String>            d = new Hashtable<String, String>();          // Print the Dictionary        System.out.println("\nDictionary: " + d);          // check if this dictionary is empty        // using isEmpty() method        if (d.isEmpty()) {            System.out.println("Dictionary "                               + "is empty");        }        else            System.out.println("Dictionary "                               + "is not empty");          // Insert elements in the hashtable        d.put("a", "GFG");        d.put("b", "gfg");          // Print the Dictionary        System.out.println("\nDictionary: " + d);          // check if this dictionary is empty        // using isEmpty() method        if (d.isEmpty()) {            System.out.println("Dictionary "                               + "is empty");        }        else            System.out.println("Dictionary "                               + "is not empty");          // Remove elements in the hashtable        d.remove("a");        d.remove("b");          // Print the Dictionary        System.out.println("\nDictionary: " + d);          // check if this dictionary is empty        // using isEmpty() method        if (d.isEmpty()) {            System.out.println("Dictionary "                               + "is empty");        }        else            System.out.println("Dictionary "                               + "is not empty");    }} |
Output:
Dictionary: {}
Dictionary is empty
Dictionary: {b=gfg, a=GFG}
Dictionary is not empty
Dictionary: {}
Dictionary is empty
Reference:https://docs.oracle.com/javase/7/docs/api/java/util/Dictionary.html#isEmpty()
