The Character.isWhitespace()
method in Java is used to determine if a specified character is a whitespace character.
Table of Contents
- Introduction
isWhitespace()
Method Syntax- Examples
- Checking Single Characters
- Handling Non-Whitespace Characters
- Checking Multiple Characters
- Real-World Use Case
- Conclusion
Introduction
The Character.isWhitespace()
method is a static method in the Character
class in Java. It checks whether a given character is a whitespace character. Whitespace characters include spaces, tabs, and other characters that separate words and symbols in text.
isWhitespace()() Method Syntax
The Character.isWhitespace()
method has two overloaded versions:
isWhitespace(char ch)
public static boolean isWhitespace(char ch)
- ch: The character to be tested.
The method returns:
true
if the character is a whitespace character.false
otherwise.
isWhitespace(int codePoint)
public static boolean isWhitespace(int codePoint)
- codePoint: The Unicode code point to be tested.
The method returns:
true
if the code point is a whitespace character.false
otherwise.
Examples
Checking Single Characters
The isWhitespace(char ch)
method can be used to check if a single character is a whitespace character.
Example
public class IsWhitespaceExample {
public static void main(String[] args) {
char spaceChar = ' ';
char nonSpaceChar = 'A';
boolean isWhitespace1 = Character.isWhitespace(spaceChar);
boolean isWhitespace2 = Character.isWhitespace(nonSpaceChar);
System.out.println("Is ' ' a whitespace character? " + isWhitespace1);
System.out.println("Is 'A' a whitespace character? " + isWhitespace2);
}
}
Output:
Is ' ' a whitespace character? true
Is 'A' a whitespace character? false
In this example, the method returns true
for the space character ' '
and false
for the non-whitespace character 'A'
.
Checking Unicode Code Points
The isWhitespace(int codePoint)
method can be used to check if a Unicode code point is a whitespace character.
Example
public class IsWhitespaceCodePointExample {
public static void main(String[] args) {
int spaceCodePoint = ' ';
int nonSpaceCodePoint = 'A';
boolean isWhitespace1 = Character.isWhitespace(spaceCodePoint);
boolean isWhitespace2 = Character.isWhitespace(nonSpaceCodePoint);
System.out.println("Is code point ' ' a whitespace character? " + isWhitespace1);
System.out.println("Is code point 'A' a whitespace character? " + isWhitespace2);
}
}
Output:
Is code point ' ' a whitespace character? true
Is code point 'A' a whitespace character? false
Handling Non-Whitespace Characters
The isWhitespace()
method returns false
for characters that are not whitespace characters.
Example
public class NonWhitespaceCharacterExample {
public static void main(String[] args) {
char digitChar = '1';
char specialChar = '$';
boolean isWhitespace1 = Character.isWhitespace(digitChar);
boolean isWhitespace2 = Character.isWhitespace(specialChar);
System.out.println("Is '1' a whitespace character? " + isWhitespace1);
System.out.println("Is '$' a whitespace character? " + isWhitespace2);
}
}
Output:
Is '1' a whitespace character? false
Is '$' a whitespace character? false
Checking Multiple Characters
You can check multiple characters to determine which ones are whitespace characters.
Example
public class MultipleCharactersExample {
public static void main(String[] args) {
char[] chars = { ' ', '\t', '\n', 'A', '1', '$' };
for (char ch : chars) {
boolean isWhitespace = Character.isWhitespace(ch);
System.out.printf("Is '%c' a whitespace character? %b%n", ch, isWhitespace);
}
}
}
Output:
Is ' ' a whitespace character? true
Is ' ' a whitespace character? true
Is '
' a whitespace character? true
Is 'A' a whitespace character? false
Is '1' a whitespace character? false
Is '$' a whitespace character? false
Real-World Use Case
Filtering Out Whitespace Characters
In a real-world application, you might need to filter out whitespace characters from a text string.
Example
public class FilterWhitespaceCharactersExample {
public static void main(String[] args) {
String text = "Hello\tWorld\n!";
StringBuilder filteredText = new StringBuilder();
for (char ch : text.toCharArray()) {
if (!Character.isWhitespace(ch)) {
filteredText.append(ch);
}
}
System.out.println("Filtered text: " + filteredText.toString());
}
}
Output:
Filtered text: HelloWorld!
In this example, the code removes the whitespace characters from the string.
Conclusion
The Character.isWhitespace()
method in Java is a simple and effective way to check if a character is a whitespace character. By understanding how to use this method and its overloaded versions, you can efficiently handle text processing tasks that involve checking for whitespace characters in your Java applications. Whether you are validating individual characters, handling Unicode code points, or processing entire strings, the isWhitespace()
method provides a reliable solution for these tasks.