The best Java Character class Tutorial In 2024, In this tutorial you can learn Escape sequence,Character Method,
Character classes are used to operate a single character.
Character class wraps a value in an object primitive type char
char ch = 'a'; // Unicode 字符表示形式 char uniChar = '\u039A'; // 字符数组 char[] charArray ={ 'a', 'b', 'c', 'd', 'e' };
However, in the actual development process, we often encounter the situation requires the use of an object, rather than built-in data types. To solve this problem, Java language provides built-in data type char wrapper classes Character classes.
Character class provides a series of methods to manipulate characters. 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, when a parameter of type char is passed to a Character type parameter method, the compiler will automatically convert to the char type parameters Character object. This feature is called boxing, in turn, called unboxing.
// 原始字符 'a' 装箱到 Character 对象 ch 中 Character ch = 'a'; // 原始字符 'x' 用 test 方法装箱 // 返回拆箱的值到 'c' char c = test('x');
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 sequence | description |
---|---|
\ T | In the text where the insertion of a tab key |
\ B | In the text where the insertion of a back button |
\ N | Where in the text wrap |
\ R | Enter in the text where the insertion |
\ F | In the text where the insert page breaks |
\ ' | Inserted in the text where a single quote |
\ " | Inserted in the text where the double quotes |
\\ | Inserted in the text where the backslash |
When you print a statement encounters an escape sequence, the compiler can be interpreted correctly.
The following examples are to escape the double quotes and outputs:
public class Test { public static void main(String args[]) { System.out.println("访问\"本教程!\""); } }
The above examples compiled results are as follows:
访问"本教程!"
Here is the Character class methods:
No. | Method and Description |
---|---|
1 | isLetter () Whether it is a letter |
2 | isDigit () Whether it is a numeric character |
3 | isWhitespace () Whether a space |
4 | isUpperCase () Whether it is uppercase |
5 | isLowerCase () It is lowercase letters |
6 | toUpperCase () Specifies uppercase letters |
7 | toLowerCase () Lowercase letters specified |
8 | toString () It returns the character string, the string length of only 1 |
For a complete list of methods, refer to the java.lang.Character API specification.