Java Character class

Character class operation for a single character.

Character classes in a package base object type char value

Examples

char CH = 'A' ; 
 
// the Unicode character representation of 
char unichar = '\ u039A' ; 
 
// character array 
char [] = {charArray 'A', 'B', 'C', 'D', 'E' };

 

However, in the actual development process, we often encounter situations require the use of objects instead of the built-in data types. To solve this problem, Java language provides a wrapper class Character classes for built-in data type char.

Character class provides a series of methods to manipulate character. You can create an object using the Character class constructor Character, for example:

Character ch = new Character('a');

 

In some cases, Java compiler will automatically create a Character object.

For example, to pass a parameter of type char Character type parameter in need of a method, the compiler will automatically convert char Character type parameter to the object. This feature is called packing, unpacking in turn called.

Examples

 

// original character 'a' ch packing objects in the Character 
Character ch = 'a' ; 
 
// original character 'x' with the test method of packing
 // value returned to the unpacking 'C' 
char C = test ( ' x ');

 

Escape Sequences

Preceded by a backslash (\) character represents the escape character, it is the compiler has a special meaning.

The following list shows the Java escape sequences:

Escape Sequences	description
\t	In the text where the tab is inserted into a
\b	In the text where the key is inserted into a retracted
\n	Where in the text wrap
\r	Where the carriage returns in the text
\f	In the text where the insert page breaks
\'	Inserted in the text where the single quote
\"	Inserted in the text where the double quotes
\\	Inserted in the text where the backslash

Examples

When the print statement encounters an escape sequence, the compiler can be correctly interpreted.

The following Examples and outputs escape double quotes:

Test.java file code:

public  class the Test { 
 
   public  static  void main (String args []) { 
      System.out.println ( "access \" novice Tutorial \ "!" ); 
   } 
}

 

The above examples compiled results are as follows:

Access "rookie Tutorial!"

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Character method

Here's how the Character class:

No.	Method and Description
1	isLetter () whether it is a letter
2	isDigit () whether a numeric character
3	isWhitespace () whether it is a blank character
4	isUpperCase () whether uppercase
5	isLowerCase () whether lowercase letters
6	toUpperCase () uppercase letters specified
7	the toLowerCase () specify a letter lowercase
8	toString () Returns a string of characters, the length of the string 1 is only

For a complete list of methods, see the java.lang.Character API specification.