Detailed explanation of the Character class in Java
Character class is used to operate on single characters.
The Character class wraps a basic type char value in the object
Instance
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 situations where we need to use objects instead of built-in data types. In order to solve this problem, the Java language provides a wrapper class Character class for the built-in data type char.
The Character class provides a series of methods to manipulate characters. You can use Character's constructor method to create a Character class object, for example:
Character ch = new Character('a');
In some cases, the Java compiler automatically creates a Character object.
For example, when a char type parameter is passed to a method that requires a Character type parameter, the compiler will automatically convert the char type parameter into a Character object. This feature is called boxing, and the converse is called unboxing.
Example
// 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');
Escape sequence
With a backslash (\) in front character represents an escape character, which has special meaning to the compiler.
The following list shows Java escape sequences:
Example
When a print statement encounters an escape sequence, the compiler can interpret it correctly.
The following example escapes double quotes and outputs:
Test.java file code:
public class Test { public static void main(String args[]) { System.out.println("访问\"菜鸟教程!\""); }}
The above example compiles and runs the results as follows:
访问"菜鸟教程!"
Character method
The following are the methods of the Character class:
[Related recommendations]
2. About the instance analysis of the packaging class Character
3. About the usage analysis of the Character class
4. Detailed explanation of instances of the Character class
5. Detailed explanation of the differences between Character and char methods
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