Java全角字符串转换为半角字符串详解编程语言

如下是用正则表达式实现的java全角转半角代码片段：

import java.util.regex.*; 
 
public static String replaceDBC2SBC(String input) { 
    Pattern pattern = Pattern.compile("[/u3000/uff01-/uff5f]{1}"); 
 
    Matcher m = pattern.matcher(input); 
    StringBuffer s = new StringBuffer(); 
    while (m.find()) { 
        char c = m.group(0).charAt(0); 
        char replacedChar = c == '　' ? ' ' : (char) (c - 0xfee0); 
        m.appendReplacement(s, String.valueOf(replacedChar)); 
    } 
 
    m.appendTail(s); 
 
    return s.toString(); 
}

单元测试代码如下：

    @Test 
    public void testReplaceQuanjiao() { 
        String text = "ab１２３ｗ我们３jkjkdfdf４４４eeee"; 
 
        String expected = "ab123w我们3jkjkdfdf444eeee"; 
        String actual = replaceDBC2SBC(text); 
 
        assertEquals(expected, actual); 
    }