原文连接
 
junit不能测struts的action，httpunit也只能测servlet。用struts作项目的时候无法方便的对action层做单元测试一直是我的心头大恨。现在好了，我们有了StrutsTestCase。按照网上的介绍，StrutsTestCase用起来应该是非常简单的，只要下了jar包回来引用到工程里面就可以了。实际上可能也差不多－－如果你运气不象我这么臭的话。

在sourceforge上随便挑其中一个镜象的下载地址：
http://aleron.dl.sourceforge.net/sourceforge/strutstestcase/strutstest213-1.2_2.4.zip
flashget回来，放到jbuilder的userhome里面，找一个struts action创建test case，创建的时候吧test case的基类改为 MockStrutsTestCase，测试的方法一个都不用选（因为我们是要针对action的具体每一个逻辑分支测试而不是具体的某一个方法）。创建成功后添加一个测试：
  public void testSuccessfulRefresh()
  {
    setRequestPathInfo("/RefreshSystemData");
    actionPerform();
    verifyForward("success");
  }
嘿嘿，我精心挑了一个没有参数的action来实验。
一切看起来很顺利。run test，噩梦开始了：
java.lang.NullPointerException
 at servletunit.struts.MockStrutsTestCase.getActionServlet(MockStrutsTestCase.java:331)
 at servletunit.struts.MockStrutsTestCase.tearDown(MockStrutsTestCase.java:130)
 at hospital.tongren.oa.system.action.TestRefreshSystemDataAction.tearDown(TestRefreshSystemDataAction.java:34)
...(Click for full stack trace)...
还好我没有开音箱，不然又是一大炮轰出来。
看来要调试了，先去同一个地方下了StrutsTestCase原码回来
 http://aleron.dl.sourceforge.net/sourceforge/strutstestcase/strutstest-213-src.zip
加进userhome里面的source。debug进去，跟到org.apache.struts.action.ActionServlet里面，出错的地方是：
        InputStream input =
            getServletContext().getResourceAsStream("/WEB-INF/web.xml");
        try {
            digester.parse(input);
        } catch (IOException e) {
....
input 为空指针。不知道为什么ServletContextSimulator在模拟ServletContext的时候没能够正确的找到webmodule的位置。上网搜了好一会儿文档，在 http://strutstestcase.sourceforge.net/api/servletunit/struts/MockStrutsTestCase.html 中发现了这样一段：
NOTE: By default, the Struts ActionServlet will look for the file WEB-INF/struts-config.xml, so you must place the directory that contains WEB-INF in your CLASSPATH. ...
先照它说的试试把webmodule路径放进classpath中，没有用。
往下看，发现了这个好东东：setContextDirectory。在startup中加一句：
this.setContextDirectory(new File("E:\\projectPath\\webModulePath\\"));
终于把那个空指针给过了。但是报一个新的异常：
junit.framework.AssertionFailedError: received error 400 : Invalid path /RefreshSystemData was requested
 at servletunit.HttpServletResponseSimulator.sendError(HttpServletResponseSimulator.java:463)
 at org.apache.struts.action.RequestProcessor.processMapping(RequestProcessor.java:684)
 at org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:242)
 at org.apache.struts.action.ActionServlet.process(ActionServlet.java:1482)
 at org.apache.struts.action.ActionServlet.doPost(ActionServlet.java:525)
 at servletunit.struts.MockStrutsTestCase.actionPerform(MockStrutsTestCase.java:394)
 at hospital.tongren.oa.system.action.TestRefreshSystemDataAction.testSuccessfulRefresh(TestRefreshSystemDataAction.java:51)
...(Click for full stack trace)...

找不到strutsconfig里面配置的path。strutsconfig是在web.xml里面配置的，应该还是web.xml没找到造成的，那么就指定strutsconfig文件的位置咯：
    setConfigFile("E:\\......\\struts-config.xml");
终于可以运行起来了。
随后发现，如果  setServletConfigFile("E:\\....\\WEB-INF\\web.xml");的话MockStrutsTestCase也能够根据web.xml中的配置找到strutsconfig文件。
最后把上面用到的绝对地址E:\\...全部改为相对地址：
    setContextDirectory(new File("modulePath\\"));
    setServletConfigFile("modulePath\\WEB-INF\\web.xml");
    //   this.setConfigFile("modulePath\\WEB-INF\\config\\system\\struts-config.xml"); 
血吐完了，继续郁闷，为什么别人都不用配置的这么麻烦呢？到底我做错了什么，还是jbuilder的错？
CactusStrutsTestCase也没配起，好像要加个什么包吧，再看看先。

[点击此处收藏本文] 
发表于 2005年01月22日 4:04 PM 

emu 发表于2005-01-22 8:00 PM  
http://jakarta.apache.org/cactus/getting_started.html 中有详细的说明。感觉确实复杂了一点。现在进展是： 

org.apache.cactus.util.ChainedRuntimeException: Failed to get the test results at [http://localhost:8083/TongRenOA/ServletRedirector] 

at org.apache.cactus.internal.client.connector.http.DefaultHttpClient.doTest_aroundBody0(DefaultHttpClient.java:92) 

at org.apache.cactus.internal.client.connector.http.DefaultHttpClient.doTest_aroundBody1$advice(DefaultHttpClient.java:206) 

at org.apache.cactus.internal.client.connector.http.DefaultHttpClient.doTest(DefaultHttpClient.java) 

at org.apache.cactus.internal.client.connector.http.HttpProtocolHandler.runWebTest(HttpProtocolHandler.java:159) 

at org.apache.cactus.internal.client.connector.http.HttpProtocolHandler.runTest_aroundBody0(HttpProtocolHandler.java:80) 

at org.apache.cactus.internal.client.connector.http.HttpProtocolHandler.runTest_aroundBody1$advice(HttpProtocolHandler.java:206) 

at org.apache.cactus.internal.client.connector.http.HttpProtocolHandler.runTest(HttpProtocolHandler.java) 

at org.apache.cactus.internal.client.ClientTestCaseCaller.runTest(ClientTestCaseCaller.java:144) 

at org.apache.cactus.internal.AbstractCactusTestCase.runBareClient(AbstractCactusTestCase.java:215) 

at org.apache.cactus.internal.AbstractCactusTestCase.runBare(AbstractCactusTestCase.java:133) 

...(Click for full stack trace)... 

下班先。

 
/*
 * A JavaScript implementation of the Secure Hash Algorithm, SHA-1, as defined
 * in FIPS PUB 180-1
 * Copyright (C) Paul Johnston 2000 - 2002.
 * See http://pajhome.org.uk/site/legal.html for details.
 */
/*
 * Convert a 32-bit number to a hex string with ms-byte first
 */
var hex_chr = "0123456789abcdef";
function hex(num)
{
  var str = "";
  for(var j = 7; j >= 0; j--)
    str += hex_chr.charAt((num >> (j * 4)) & 0x0F);
  return str;
}
/*
 * Convert a string to a sequence of 16-word blocks, stored as an array.
 * Append padding bits and the length, as described in the SHA1 standard.
 */
function str2blks_SHA1(str)
{
  var nblk = ((str.length + 8) >> 6) + 1;
  var blks = new Array(nblk * 16);
  for(var i = 0; i < nblk * 16; i++) blks[i] = 0;
  for(var i = 0; i < str.length; i++)
    blks[i >> 2] |= str.charCodeAt(i) << (24 - (i % 4) * 8);
  blks[i >> 2] |= 0x80 << (24 - (i % 4) * 8);
  blks[nblk * 16 - 1] = str.length * 8;
  return blks;
}
/*
 * Add integers, wrapping at 2^32. This uses 16-bit operations internally
 * to work around bugs in some JS interpreters.
 */
function safe_add(x, y)
{
  var lsw = (x & 0xFFFF) + (y & 0xFFFF);
  var msw = (x >> 16) + (y >> 16) + (lsw >> 16);
  return (msw << 16) | (lsw & 0xFFFF);
}
/*
 * Bitwise rotate a 32-bit number to the left
 */
function rol(num, cnt)
{
  return (num << cnt) | (num >>> (32 - cnt));
}
/*
 * Perform the appropriate triplet combination function for the current
 * iteration
 */
function ft(t, b, c, d)
{
  if(t < 20) return (b & c) | ((~b) & d);
  if(t < 40) return b ^ c ^ d;
  if(t < 60) return (b & c) | (b & d) | (c & d);
  return b ^ c ^ d;
}
/*
 * Determine the appropriate additive constant for the current iteration
 */
function kt(t)
{
  return (t < 20) ?  1518500249 : (t < 40) ?  1859775393 :
         (t < 60) ? -1894007588 : -899497514;
}
/*
 * Take a string and return the hex representation of its SHA-1.
 */
function calcSHA1(str)
{
  var x = str2blks_SHA1(str);
  var w = new Array(80);
  var a =  1732584193;
  var b = -271733879;
  var c = -1732584194;
  var d =  271733878;
  var e = -1009589776;
  for(var i = 0; i < x.length; i += 16)
  {
    var olda = a;
    var oldb = b;
    var oldc = c;
    var oldd = d;
    var olde = e;
    for(var j = 0; j < 80; j++)
    {
      if(j < 16) w[j] = x[i + j];
      else w[j] = rol(w[j-3] ^ w[j-8] ^ w[j-14] ^ w[j-16], 1);
      var t = safe_add(safe_add(rol(a, 5), ft(j, b, c, d)), safe_add(safe_add(e, w[j]), kt(j)));
      e = d;
      d = c;
      c = rol(b, 30);
      b = a;
      a = t;
    }
    a = safe_add(a, olda);
    b = safe_add(b, oldb);
    c = safe_add(c, oldc);
    d = safe_add(d, oldd);
    e = safe_add(e, olde);
  }
  return hex(a) + hex(b) + hex(c) + hex(d) + hex(e);
}


java版的MD5 








 

 
public class MD5
{
  /*
   * A Java implementation of the RSA Data Security, Inc. MD5 Message
   * Digest Algorithm, as defined in RFC 1321.
   * Based on the JavaScript implementation of Paul Johnston
   *      Copyright (C) Paul Johnston 1999 - 2000.
   *      See http://pajhome.org.uk/site/legal.html for details.
   * Java Version by Thomas Weber (Orange Interactive GmbH)
   */
  
  /*
   * Convert a 32-bit number to a hex string with ls-byte first
   */
  String hex_chr = "0123456789abcdef";
  private String rhex(int num)
  {
    String str = "";
    for(int j = 0; j <= 3; j++)
      str = str + hex_chr.charAt((num >> (j * 8 + 4)) & 0x0F) + hex_chr.charAt((num >> (j * 8)) & 0x0F);
    return str;
  }
  
  /*
   * Convert a string to a sequence of 16-word blocks, stored as an array.
   * Append padding bits and the length, as described in the MD5 standard.
   */
  private int[] str2blks_MD5(String str)
  {
    int nblk = ((str.length() + 8) >> 6) + 1;
    int[] blks = new int[nblk * 16];
    int i = 0;
    for(i = 0; i < nblk * 16; i++) {
      blks[i] = 0;
    }
    for(i = 0; i < str.length(); i++) {
      blks[i >> 2] |= str.charAt(i) << ((i % 4) * 8);
    }
    blks[i >> 2] |= 0x80 << ((i % 4) * 8);
    blks[nblk * 16 - 2] = str.length()*8;
      
    return blks;
  }
  
  /*
   * Add integers, wrapping at 2^32
   */
  private int add(int x, int y)
  {
    return ((x&0x7FFFFFFF) + (y&0x7FFFFFFF)) ^ (x&0x80000000) ^ (y&0x80000000);
  }
  
  /*
   * Bitwise rotate a 32-bit number to the left
   */
  private int rol(int num, int cnt)
  {
    return (num << cnt) | (num >>> (32 - cnt));
  }
  
  /*
   * These functions implement the basic operation for each round of the
   * algorithm.
   */
  private int cmn(int q, int a, int b, int x, int s, int t)
  {
    return add(rol(add(add(a, q), add(x, t)), s), b);
  }
  private int ff(int a, int b, int c, int d, int x, int s, int t)
  {
    return cmn((b & c) | ((~b) & d), a, b, x, s, t);
  }
  private int gg(int a, int b, int c, int d, int x, int s, int t)
  {
    return cmn((b & d) | (c & (~d)), a, b, x, s, t);
  }
  private int hh(int a, int b, int c, int d, int x, int s, int t)
  {
    return cmn(b ^ c ^ d, a, b, x, s, t);
  }
  private int ii(int a, int b, int c, int d, int x, int s, int t)
  {
    return cmn(c ^ (b | (~d)), a, b, x, s, t);
  }
  
  /*
   * Take a string and return the hex representation of its MD5.
   */
  public String calcMD5(String str)
  {
    int[] x = str2blks_MD5(str);
    int a = 0x67452301;
    int b = 0xEFCDAB89;
    int c = 0x98BADCFE;
    int d = 0x10325476;
  
    for(int i = 0; i < x.length; i += 16)
    {
      int olda = a;
      int oldb = b;
      int oldc = c;
      int oldd = d;
  
      a = ff(a, b, c, d, x[i+ 0], 7 , 0xD76AA478);
      d = ff(d, a, b, c, x[i+ 1], 12, 0xE8C7B756);
      c = ff(c, d, a, b, x[i+ 2], 17, 0x242070DB);
      b = ff(b, c, d, a, x[i+ 3], 22, 0xC1BDCEEE);
      a = ff(a, b, c, d, x[i+ 4], 7 , 0xF57C0FAF);
      d = ff(d, a, b, c, x[i+ 5], 12, 0x4787C62A);
      c = ff(c, d, a, b, x[i+ 6], 17, 0xA8304613);
      b = ff(b, c, d, a, x[i+ 7], 22, 0xFD469501);
      a = ff(a, b, c, d, x[i+ 8], 7 , 0x698098D8);
      d = ff(d, a, b, c, x[i+ 9], 12, 0x8B44F7AF);
      c = ff(c, d, a, b, x[i+10], 17, 0xFFFF5BB1);
      b = ff(b, c, d, a, x[i+11], 22, 0x895CD7BE);
      a = ff(a, b, c, d, x[i+12], 7 , 0x6B901122);
      d = ff(d, a, b, c, x[i+13], 12, 0xFD987193);
      c = ff(c, d, a, b, x[i+14], 17, 0xA679438E);
      b = ff(b, c, d, a, x[i+15], 22, 0x49B40821);
  
      a = gg(a, b, c, d, x[i+ 1], 5 , 0xF61E2562);
      d = gg(d, a, b, c, x[i+ 6], 9 , 0xC040B340);
      c = gg(c, d, a, b, x[i+11], 14, 0x265E5A51);
      b = gg(b, c, d, a, x[i+ 0], 20, 0xE9B6C7AA);
      a = gg(a, b, c, d, x[i+ 5], 5 , 0xD62F105D);
      d = gg(d, a, b, c, x[i+10], 9 , 0x02441453);
      c = gg(c, d, a, b, x[i+15], 14, 0xD8A1E681);
      b = gg(b, c, d, a, x[i+ 4], 20, 0xE7D3FBC8);
      a = gg(a, b, c, d, x[i+ 9], 5 , 0x21E1CDE6);
      d = gg(d, a, b, c, x[i+14], 9 , 0xC33707D6);
      c = gg(c, d, a, b, x[i+ 3], 14, 0xF4D50D87);
      b = gg(b, c, d, a, x[i+ 8], 20, 0x455A14ED);
      a = gg(a, b, c, d, x[i+13], 5 , 0xA9E3E905);
      d = gg(d, a, b, c, x[i+ 2], 9 , 0xFCEFA3F8);
      c = gg(c, d, a, b, x[i+ 7], 14, 0x676F02D9);
      b = gg(b, c, d, a, x[i+12], 20, 0x8D2A4C8A);
  
      a = hh(a, b, c, d, x[i+ 5], 4 , 0xFFFA3942);
      d = hh(d, a, b, c, x[i+ 8], 11, 0x8771F681);
      c = hh(c, d, a, b, x[i+11], 16, 0x6D9D6122);
      b = hh(b, c, d, a, x[i+14], 23, 0xFDE5380C);
      a = hh(a, b, c, d, x[i+ 1], 4 , 0xA4BEEA44);
      d = hh(d, a, b, c, x[i+ 4], 11, 0x4BDECFA9);
      c = hh(c, d, a, b, x[i+ 7], 16, 0xF6BB4B60);
      b = hh(b, c, d, a, x[i+10], 23, 0xBEBFBC70);
      a = hh(a, b, c, d, x[i+13], 4 , 0x289B7EC6);
      d = hh(d, a, b, c, x[i+ 0], 11, 0xEAA127FA);
      c = hh(c, d, a, b, x[i+ 3], 16, 0xD4EF3085);
      b = hh(b, c, d, a, x[i+ 6], 23, 0x04881D05);
      a = hh(a, b, c, d, x[i+ 9], 4 , 0xD9D4D039);
      d = hh(d, a, b, c, x[i+12], 11, 0xE6DB99E5);
      c = hh(c, d, a, b, x[i+15], 16, 0x1FA27CF8);
      b = hh(b, c, d, a, x[i+ 2], 23, 0xC4AC5665);
  
      a = ii(a, b, c, d, x[i+ 0], 6 , 0xF4292244);
      d = ii(d, a, b, c, x[i+ 7], 10, 0x432AFF97);
      c = ii(c, d, a, b, x[i+14], 15, 0xAB9423A7);
      b = ii(b, c, d, a, x[i+ 5], 21, 0xFC93A039);
      a = ii(a, b, c, d, x[i+12], 6 , 0x655B59C3);
      d = ii(d, a, b, c, x[i+ 3], 10, 0x8F0CCC92);
      c = ii(c, d, a, b, x[i+10], 15, 0xFFEFF47D);
      b = ii(b, c, d, a, x[i+ 1], 21, 0x85845DD1);
      a = ii(a, b, c, d, x[i+ 8], 6 , 0x6FA87E4F);
      d = ii(d, a, b, c, x[i+15], 10, 0xFE2CE6E0);
      c = ii(c, d, a, b, x[i+ 6], 15, 0xA3014314);
      b = ii(b, c, d, a, x[i+13], 21, 0x4E0811A1);
      a = ii(a, b, c, d, x[i+ 4], 6 , 0xF7537E82);
      d = ii(d, a, b, c, x[i+11], 10, 0xBD3AF235);
      c = ii(c, d, a, b, x[i+ 2], 15, 0x2AD7D2BB);
      b = ii(b, c, d, a, x[i+ 9], 21, 0xEB86D391);
  
      a = add(a, olda);
      b = add(b, oldb);
      c = add(c, oldc);
      d = add(d, oldd);
    }
    return rhex(a) + rhex(b) + rhex(c) + rhex(d);
  }
}
上面是算法的实现代码，不过我们真正用的时候当然不需要那么复杂了，jdk里面早就有了高效的算法实现：
package myreuse.common.util;
import sun.misc.BASE64Encoder;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
public abstract class MessageDigester
{
  static MessageDigest SHA1 ;
  static MessageDigest MD5 ;
  static {
    try{
      SHA1 = MessageDigest.getInstance("SHA1");
      MD5 = MessageDigest.getInstance("MD5");
    } catch (NoSuchAlgorithmException e){
      e.printStackTrace();
    }
  }
  public static byte[] SHA1(String msg)
  {
    return SHA1.digest(msg.getBytes());
  }
  public static byte[] MD5(String msg)
  {
    return MD5.digest(msg.getBytes());
  }
  private static BASE64Encoder bASE64Encoder = new BASE64Encoder();
  public static String hex(byte[] b)
  {
    StringBuffer result = new StringBuffer(b.length);
    for (int i = 0; i < b.length; i++)
      result.append(Integer.toHexString(0xff & b[i]));
    return result.toString();
  }
  public static String base64(byte[] b)
  {
    String result = bASE64Encoder.encode(b);
    int i = result.indexOf('=');
    if (i>-1) result = result.substring(0,i);
    return result;
  }
  public static String base64SHA1(String msg)
  {
    return base64(SHA1(msg));
  }
  public static String base64MD5(String msg)
  {
    return base64(MD5(msg));
  }
  public static String hexSHA1(String msg)
  {
    return hex(SHA1(msg));
  }
  public static String hexMD5(String msg)
  {
    return hex(MD5(msg));
  }
}

 
class  EscapeUnescape
{
 public static String  escape (String src)
 {
  int i;
  char j;
  StringBuffer tmp = new StringBuffer();
  tmp.ensureCapacity(src.length()*6);
  for (i=0;i<src.length() ;i++ )
  {
   j = src.charAt(i);
   if (Character.isDigit(j) || Character.isLowerCase(j) || Character.isUpperCase(j))
    tmp.append(j);
   else
    if (j<256)
    {
    tmp.append( "%" );
    if (j<16)
     tmp.append( "0" );
    tmp.append( Integer.toString(j,16) );
    }
    else
    {
    tmp.append( "%u" );
    tmp.append( Integer.toString(j,16) );
    }
  }
  return tmp.toString();
 }
 public static String  unescape (String src)
 {
  StringBuffer tmp = new StringBuffer();
  tmp.ensureCapacity(src.length());
  int  lastPos=0,pos=0;
  char ch;
  while (lastPos<src.length())
  {
   pos = src.indexOf("%",lastPos);
   if (pos == lastPos)
    {
    if (src.charAt(pos+1)=='u')
     {
     ch = (char)Integer.parseInt(src.substring(pos+2,pos+6),16);
     tmp.append(ch);
     lastPos = pos+6;
     }
    else
     {
     ch = (char)Integer.parseInt(src.substring(pos+1,pos+3),16);
     tmp.append(ch);
     lastPos = pos+3;
     }
    }
   else
    {
    if (pos == -1)
     {
     tmp.append(src.substring(lastPos));
     lastPos=src.length();
     }
    else
     {
     tmp.append(src.substring(lastPos,pos));
     lastPos=pos;
     }
    }
  }
  return tmp.toString();
 }
 public static void main(String[] args) 
 {
  String tmp="~!@#$%^&*()_+|\\=-,./?><;'][{}\"";
  System.out.println("testing escape : "+tmp);
  tmp =escape(tmp);
  System.out.println(tmp);
  System.out.println("testing unescape :"+tmp);
  System.out.println(unescape(tmp));
 }
}

 
我们经常将Excel格式的文件保存为csv格式以方便上传和修改，可是当数据中包含逗号和双引号的时候Excel会把该字段用双引号括住并把数据中的"改为""，从而给解析带来了困难。我写了以下函数来解析这样的字符串：
testSplitCSV.java:
import java.util.Vector;
class  testSplitCSV{
 /**
 * Split one line of csv file
 * @return a String array results
 */
 public static String[] splitCSV(String src) throws Exception{
  if (src==null || src.equals("")) return new String[0];
  StringBuffer st=new StringBuffer();
  Vector result=new Vector();
  boolean beginWithQuote = false;
  for (int i=0;i<src.length();i++){
   char ch = src.charAt(i);
   if (ch=='\"'){
    if (beginWithQuote){
     i++;
     if (i>=src.length()){
      result.addElement(st.toString());
      st=new StringBuffer();
      beginWithQuote=false;
     }else{
      ch=src.charAt(i);
      if (ch == '\"'){
       st.append(ch);
      }else if (ch == ','){
       result.addElement(st.toString());
       st=new StringBuffer();
       beginWithQuote = false;
      }else{
       throw new Exception("Single double-quote char mustn't exist in filed "+(result.size()+1)+" while it is begined with quote\nchar at:"+i);
      }
     }
    }else if (st.length()==0){
     beginWithQuote = true;
    }else{
     throw new Exception("Quote cannot exist in a filed which doesn't begin with quote!\nfield:"+(result.size()+1));
    }
   }else if (ch==','){
    if (beginWithQuote){
     st.append(ch);
    }else{
     result.addElement(st.toString());
     st=new StringBuffer();
     beginWithQuote = false;
    }
   }else{
    st.append(ch);
   }
  }
  if (st.length()!=0){
   if (beginWithQuote){
    throw new Exception("last field is begin with but not end with double quote");
   }else{
    result.addElement(st.toString());
   }
  }
  String rs[] = new String[result.size()];
  for (int i=0;i<rs.length;i++){
   rs[i]=(String)result.elementAt(i);
  }
 return rs;
 }
 public static void main(String[] args){
  String src1=  "\"fh,zg\",sdf,\"asfs,\",\",dsdf\",\"aadf\"\"\",\"\"\"hdfg\",\"fgh\"\"dgnh\",hgfg'dfh,\"asdfa\"\"\"\"\",\"\"\"\"\"fgjhg\",\"gfhg\"\"\"\"hb\"";
  try {
   String[] Ret = splitCSV(src1);
   for (int i=0;i<Ret.length;i++){
    System.out.println(i+": "+Ret[i]);
   }
  }
  catch(Exception e) {
   e.printStackTrace();
  }
 }
}