content: /*
   *  Copyright Beijing 58 Information Technology Co.,Ltd.
   *
   *  Licensed to the Apache Software Foundation (ASF) under one
   *  or more contributor license agreements.  See the NOTICE file
   *  distributed with this work for additional information
   *  regarding copyright ownership.  The ASF licenses this file
   *  to you under the Apache License, Version 2.0 (the
   *  "License"); you may not use this file except in compliance
   *  with the License.  You may obtain a copy of the License at
   *
   *        http://www.apache.org/licenses/LICENSE-2.0
   *
   *  Unless required by applicable law or agreed to in writing,
   *  software distributed under the License is distributed on an
   *  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
   *  KIND, either express or implied.  See the License for the
   *  specific language governing permissions and limitations
   *  under the License.
   */
  package com.bj58.spat.gaea.server.secure;
  
  import java.io.UnsupportedEncodingException;
  import java.util.Random;
  /**
   * StringUtils
   * 
   * @author Service Platform Architecture Team (spat@58.com)
   */
  public class StringUtils {
  	/**
       * 使用ISO_8859_1字符集将此 String 编码为 byte序列
       * @param string 
       * @return
       */
      public static byte[] getBytesIso8859_1(String string) {
          return StringUtils.getBytesUnchecked(string, CharEncoding.ISO_8859_1);
      }
      /**
       * 使用UTF_16字符集将此 String 编码为 byte序列
       * @param string 
       * @return
       */
      public static byte[] getBytesUtf16(String string) {
          return StringUtils.getBytesUnchecked(string, CharEncoding.UTF_16);
      }
      /**
       * 使用UTF_8字符集将此 String 编码为 byte序列
       * @param string 
       * @return
       */
      public static byte[] getBytesUtf8(String string) {
          return StringUtils.getBytesUnchecked(string, CharEncoding.UTF_8);
      }
      /**
       * 使用指定的字符集将此 String 编码为 byte序列
       * @param string 
       * @param charsetName 编码格式
       * @return
       */
      public static byte[] getBytesUnchecked(String string, String charsetName) {
          if (string == null) {
              return null;
          }
          try {
              return string.getBytes(charsetName);
          } catch (UnsupportedEncodingException e) {
              throw StringUtils.newIllegalStateException(charsetName, e);
          }
      }
  
      private static IllegalStateException newIllegalStateException(String charsetName, UnsupportedEncodingException e) {
          return new IllegalStateException(charsetName + ": " + e);
      }
      
      /**
       * 通过使用指定的 charset 解码指定的 byte 数组，构造一个新的 String
       * @param bytes
       * @param charsetName
       * @return
       */
      public static String newString(byte[] bytes, String charsetName) {
          if (bytes == null) {
              return null;
          }
          try {
              return new String(bytes, charsetName);
          } catch (UnsupportedEncodingException e) {
              throw StringUtils.newIllegalStateException(charsetName, e);
          }
      }
      /**
       * 通过ISO-8859-1 解码指定的 byte 数组,构造一个新的 String
       * @param bytes
       * @return
       */
      public static String newStringIso8859_1(byte[] bytes) {
          return StringUtils.newString(bytes, CharEncoding.ISO_8859_1);
      }
      /**
       * 通过UTF_16 解码指定的 byte 数组,构造一个新的 String
       * @param bytes
       * @return
       */
      public static String newStringUtf16(byte[] bytes) {
          return StringUtils.newString(bytes, CharEncoding.UTF_16);
      }
      /**
       * 通过utf-8 解码指定的 byte 数组,构造一个新的 String
       * @param bytes
       * @return
       */
      public static String newStringUtf8(byte[] bytes) {
          return StringUtils.newString(bytes, CharEncoding.UTF_8);
      }
      
      private static final String[] ENCODE_TABLE = {
          "A", "B", "C", "D", "E", "F", "G", "H", "I", "J", "K", "L", "M",
          "N", "O", "P", "Q", "R", "S", "T", "U", "V", "W", "X", "Y", "Z",
          "a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m",
          "n", "o", "p", "q", "r", "s", "t", "u", "v", "w", "x", "y", "z",
          "0", "1", "2", "3", "4", "5", "6", "7", "8", "9"};
      
      /**
       * 随机返回8位长度的字符串
       * @return
       */
      public static String getRandomNumAndStr(int length){
      	StringBuffer sbuffer = new StringBuffer("");
      	Random r = new Random();
      	for(int i=0;i<length;i++){
      		sbuffer.append(ENCODE_TABLE[r.nextInt(62)]);
      	}
      	return sbuffer.toString();
      }
  }
  