Java_正则表达式验证用户名长度

import java.util.regex.Matcher;  
import java.util.regex.Pattern;  
  
public class UserReg {  
    /** 
     * 验证用户名，支持中英文（包括全角字符）、数字、下划线和减号 （全角及汉字算两位）,长度为4-20位,中文按二位计数 
     *  
     * @param userName 
     * @return 
     */  
    public static boolean validateUserName(String userName) {  
        String validateStr = "^[\\w\\-－＿[０-９]\u4e00-\u9fa5\uFF21-\uFF3A\uFF41-\uFF5A]+$";  
        boolean rs = false;  
        rs = matcher(validateStr, userName);  
        if (rs) {  
            int strLenth = getStrLength(userName);  
            if (strLenth < 4 || strLenth > 20) {  
                rs = false;  
            }  
        }  
        return rs;  
    }  
  
    /** 
     * 获取字符串的长度，对双字符（包括汉字）按两位计数 
     *  
     * @param value 
     * @return 
     */  
    public static int getStrLength(String value) {  
        int valueLength = 0;  
        String chinese = "[\u0391-\uFFE5]";  
        for (int i = 0; i < value.length(); i++) {  
            String temp = value.substring(i, i + 1);  
            if (temp.matches(chinese)) {  
                valueLength += 2;  
            } else {  
                valueLength += 1;  
            }  
        }  
        return valueLength;  
    }  
  
    private static boolean matcher(String reg, String string) {  
        boolean tem = false;  
        Pattern pattern = Pattern.compile(reg);  
        Matcher matcher = pattern.matcher(string);  
        tem = matcher.matches();  
        return tem;  
    }  
  
    public static void main(String[] args) {  
        String str = "０－＿ｆ９ｚｄ中22最代码zuidaima.com";  
        String st = "Ａ-ｄｑ_!!！！去符号标号！ノチセたのひちぬ！当然。!!..**半角最代码zuidaima.com";  
  
        System.out.println(validateUserName(str));  
        System.out.println(st.replaceAll("[\\pP&&[^-_]]", ""));  
        System.out.println(st.replaceAll("[\\w\\-一-龥Ａ-Ｚａ-ｚ]", ""));  
    }  
}