Java Character isDigit() Method

The isDigit(int codePoint) method of Character class generally determines whether the given character is a digit or not. Generally, a character is considered as a digit if its general category given by getType(codePoint), is DECIMAL_DIGIT_NUMBER.

Syntax

Parameter

The above method requires only one parameter:

a.)The codePoint which is a Unicode character that needs to be tested.

Return Value

The isDigit(int codePoint) method returns a boolean value i.e. true, if the given(or specified) character is a digit. Otherwise, the method returns false.

Example 1

public class JavaCharacaterisDigitintcodePointExample1 {
public static void main(String[] args) {		
		// Initialize the codePoints.
		int codepoint1 = 55;
		int codepoint2 = 32;
		int codepoint3 = 121;
		int codepoint4 = 49;
		int codepoint5 = 200;	
		// Check whether a particular codePoint is a digit or not.
		boolean check1 = Character.isDigit(codepoint1);
		boolean check2 = Character.isDigit(codepoint2);
		boolean check3 = Character.isDigit(codepoint3);
		boolean check4 = Character.isDigit(codepoint4);
		boolean check5 = Character.isDigit(codepoint5);
		// Print the result.
		if(check1){
		System.out.print("The codePoint \'"+codepoint1+"\' is a digit.\n");
		}
		else{
		System.out.print("The codePoint \'"+codepoint1+"\' is not a digit.\n");
		}
		if(check2){
		System.out.print("The codePoint \'"+codepoint2+"\' is a digit.\n");
		}
		else{
		System.out.print("The codePoint \'"+codepoint2+"\' is not a digit.\n");
		}
		if(check3){
		System.out.print("The codePoint \'"+codepoint3+"\' is a digit.\n");
		}
		else{
		System.out.print("The codePoint \'"+codepoint3+"\' is not a digit.\n");
		}	
		if(check4){
		System.out.print("The codePoint \'"+codepoint4+"\' is a digit.\n");
		}
		else{
		System.out.print("The codePoint \'"+codepoint4+"\' is not a digit.\n");
		}
		if(check5){
		System.out.print("The codePoint \'"+codepoint5+"\' is a digit.\n");
		}
		else{
		System.out.print("The codePoint \'"+codepoint5+"\' is not a digit.\n");
		}	
	}
}

Output:

The codePoint '55' is a digit.
The codePoint '32' is not a digit.
The codePoint '121' is not a digit.
The codePoint '49' is a digit.
The codePoint '200' is not a digit.

Example 2

public class JavaCharacaterisDigitintcodePointExample2 {
	  public static void main(String[] args) {
	     // Create four int primitives obj1, obj2, obj3 and obj4.
	      int obj1, obj2, obj3, obj4;
	     // Assign the values to obj1, obj2, obj3 and obj4.
	      obj1 = 0x06f8;
	      obj2 = 0x0432;
	      obj3 = 0x50;
	      obj4 = 0x0c12;
	     // Create four boolean primitives b1, b2, b3 and b4.
	      boolean b1, b2, b3, b4;
	     // Assign the isDigit method
	      b1 = Character.isDigit(obj1);
	      b2 = Character.isDigit(obj2);
	      b3 = Character.isDigit(obj3);
	      b4 = Character.isDigit(obj4);
	      String str1 = "The first object represents a digit :  " + b1;
	      String str2 = "The first object represents a digit :  " + b2;
	      String str3 = "The first object represents a digit :  " + b3;
	      String str4 = "The first object represents a digit :  " + b4;
	      // Print the values of b1, b2, b3 and b4.
	      System.out.println( str1 );
	      System.out.println( str2 );
	      System.out.println( str3 );
	      System.out.println( str4 );
	   }
}

Output:

The first object represents a digit :  true
The first object represents a digit :  false
The first object represents a digit :  false
The first object represents a digit :  false