char

char Type in Java

Overview

In Java, the char type is used to store a single 16-bit Unicode character. It can represent any character from the Unicode standard, making it suitable for international text handling and character-based operations.

Key Features of char:

1. Size: 16 bits (2 bytes), allows representation of characters in the Unicode set.
2. Default Value: '\u0000' (null character).
3. Range: '\u0000' (0) to '\uffff' (65,535).

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Examples of Characters

Type	Examples
Letters	'A', 'z', 'k'
Digits	'1', '9'
Special Symbols	'#', '%', '@'
Unicode	'\u0041' (A), '\u03A9' (Ω)

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Common Operations on char

Arithmetic Operations

Although char stores characters, it can participate in arithmetic operations because it is internally stored as an integer representing the Unicode value.

Operation	Symbol	Example
Increment	++	charValue++
Decrement	--	charValue--
Addition	+	'A' + 1 → 'B'
Subtraction	-	'C' - 1 → 'B'

Relational Operations

Operation	Symbol	Example
Equal to	==	'A' == 'A'
Not equal to	!=	'A' != 'B'
Greater than	>	'B' > 'A'
Less than	<	'A' < 'B'
Greater than or equal to	>=	'B' >= 'A'
Less than or equal to	<=	'A' <= 'B'

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Type Casting

Implicit Casting (Widening)

• char can be implicitly cast to int.
  • Example:

    char charValue = 'A';
    int intValue = charValue;  // Automatically converts 'A' to 65

Explicit Casting (Narrowing)

• Converting int to char requires explicit casting.
  • Example:

    int intValue = 66;
    char charValue = (char) intValue;  // Converts 66 to 'B'

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Unicode and Escape Sequences

• Unicode Representation: Use \u followed by a 4-digit hexadecimal code.
  • Example: '\u0041' represents 'A'.
• Escape Characters:

  Escape Sequence	Description
  \n	New line
  \t	Tab
  \'	Single quote
  \"	Double quote
  \\	Backslash

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Example Code

public class CharExamples {
    public static void main(String[] args) {
        // Initialize char variables
        char letter = 'A';
        char digit = '5';
        char symbol = '#';
        char unicodeChar = '\u03A9';  // Omega (Ω)

        // Print char values
        System.out.println("Letter: " + letter);
        System.out.println("Digit: " + digit);
        System.out.println("Symbol: " + symbol);
        System.out.println("Unicode Character: " + unicodeChar);

        // Arithmetic Operations
        char nextLetter = (char) (letter + 1);  // Increment to next character
        System.out.println("Next Letter: " + nextLetter);

        // Relational Operations
        System.out.println("Is 'A' equal to 'B'? " + (letter == 'B'));
        System.out.println("Is 'A' less than 'B'? " + (letter < 'B'));

        // Type Casting
        int unicodeValue = letter;  // Implicit cast to int
        System.out.println("Unicode value of 'A': " + unicodeValue);

        char fromInt = (char) 66;  // Explicit cast from int to char
        System.out.println("Character from 66: " + fromInt);
    }
}

For more: CharDataType.java