Java 字符數(shù)據(jù)類型

Java數(shù)據(jù)類型教程 - Java字符數(shù)據(jù)類型

Character類的一個(gè)對(duì)象包裝一個(gè)char值。

字符類包含isLetter()和isDigit()方法來檢查字符是否為字母和數(shù)字。

toUpperCase()和toLowerCase()方法將字符轉(zhuǎn)換為大寫和小寫。

該類提供了一個(gè)構(gòu)造函數(shù)和一個(gè)工廠valueOf()方法來從char創(chuàng)建對(duì)象。

charValue()方法返回對(duì)象包裝的char。

例子

以下代碼顯示了如何創(chuàng)建Character對(duì)象以及如何使用它們的一些方法：

public class Main {
  public static void main(String[] args) {
    // Using the constructor
    Character c1 = new Character("A");

    // Using the factory method - preferred
    Character c2 = Character.valueOf("2");
    Character c3 = Character.valueOf("-");

    // Getting the wrapped char values
    char cc1 = c1.charValue();
    char cc2 = c2.charValue();
    char cc3 = c3.charValue();

    System.out.println("c1 = " + c1);
    System.out.println("c2 = " + c2);
    System.out.println("c3 = " + c3);

    // Using some Character class methods on c1
    System.out.println("isLowerCase c1    = " + Character.isLowerCase(cc1));
    System.out.println("isDigit c1    = " + Character.isDigit(cc1));
    System.out.println("isLetter c1    = " + Character.isLetter(cc1));
    System.out.println("Lowercase of  c1    = " + Character.toLowerCase(cc1));

    // Using some Character class methods on c2
    System.out.println("isLowerCase c2    = " + Character.isLowerCase(cc2));
    System.out.println("isDigit c2    = " + Character.isDigit(cc2));
    System.out.println("isLetter c2    = " + Character.isLetter(cc2));
    System.out.println("Lowercase of  c2    = " + Character.toLowerCase(cc2));

    System.out.println("Uppercase of  c3    = " + Character.toUpperCase(cc3));

  }
}

上面的代碼生成以下結(jié)果。