字符串工具类

package com.cmos.ngoc.util;

import java.util.regex.Matcher;
import java.util.regex.Pattern;

/**
 * 字符串工具类
 * 
 */
public final class StringUtil {
    /** Private Constructor **/
    private StringUtil() {
    }
    
    /**
     * 判断字符串是否非null && 非空字符 
     * 
     * @param param
     * @return
     */
    public static boolean isNotEmpty(String param) {
        return param != null && !"".equals(param.trim());
    }

    /**
     * 判断字符串是否为null || 空字符串
     * 
     * @param param
     * @return
     */
    public static boolean isEmpty(String param) {
        return param == null || "".equals(param.trim());
    }
    
    /**
     * 判断是否为数�?
     * @param str
     * @return True为数�?
     */
    public static boolean isNum(String str) {
        String regex = "^(-?\\d+)(\\.\\d+)?$";
        return matchRegex(str, regex);
    }
    
    private static boolean matchRegex(String value, String regex) {
        Pattern pattern = Pattern.compile(regex);
        Matcher matcher = pattern.matcher(value);
        return matcher.matches();
    }
}