content: package com.soecode.wxtools.util;
  
  import java.util.Random;
  
  /**
   * copy from apache-commons-lang3
   */
  public class StringUtils {
  
  	public static boolean isBlank(CharSequence cs) {
  		int strLen;
  		if (cs == null || (strLen = cs.length()) == 0) {
  			return true;
  		}
  		for (int i = 0; i < strLen; i++) {
  			if (Character.isWhitespace(cs.charAt(i)) == false) {
  				return false;
  			}
  		}
  		return true;
  	}
  
  	public static boolean isNotBlank(CharSequence cs) {
  		return !StringUtils.isBlank(cs);
  	}
  
  	public static boolean isEmpty(CharSequence cs) {
  		return cs == null || cs.length() == 0;
  	}
  
  	public static boolean isNotEmpty(CharSequence cs) {
  		return !StringUtils.isEmpty(cs);
  	}
  	
  	public static String randomStr(int length) {
  	    String base = "abcdefghijklmnopqrstuvwxyz0123456789";     
  	    Random random = new Random();     
  	    StringBuffer sb = new StringBuffer();     
  	    for (int i = 0; i < length; i++) {     
  	        int number = random.nextInt(base.length());     
  	        sb.append(base.charAt(number));     
  	    }     
  	    return sb.toString();     
  	 } 
  	
  }
  