// Listing 2: controller.java

protected final void doPost(
    HttpServletRequest request,
    HttpServletResponse response) {

    // begining codes
    //--用戶已通過身份驗證
    if (((String) request.getAttribute("login")).equals
       ("login success")) {
        ArrayList actionreport = new ArrayList();
        actionreport.add("Correct Password");
        session.setAttribute("actionreport", actionreport);
        nextPage = "success.jsp";
    }
    if (dispatch) {
        RequestDispatcher rd =
            getServletContext().getRequestDispatcher(nextPage);
        rd.forward(request, response);
    } else {

        session.invalidate();

    }
    // ending codes
}

問題：JavaBean的一個寫文件方法，獨立調(diào)試正常。但移到Struts下，通過Action調(diào)用時，

拋出異常。

原因：文件路徑問題

解決方法：

1.修改原來JavaBean里帶前綴路徑的文件---"resources/users.properties"

為"users.properties"

2.將struts框架下的源文件users.properties，直接移到src下

3.重新編譯，部署

4.運行這個注冊組件成功后，可以到$服務(wù)器主目錄$/bin下，查看這個已經(jīng)寫過的

users.properties文件

以上問題，曾嘗試將resources/user.properite改為絕對路徑"d:/users.properties"，

或改為相對路徑"/resources/properties"，或直接向JavaBean中傳入路徑參數(shù)path，

path=request.getRealPath("")(或request.getContextPath)等，均沒有調(diào)試成功。

故記錄下來，希望其它網(wǎng)友遇到時，不必再做這樣的重復(fù)勞動。

附：

1.Action中調(diào)用方法:

UserDirectory.getInstance().setUser(userName,password1);

2.JavaBean的縮略代碼：

UserDirectory.java

import java.io.IOException;
import java.io.FileOutputStream;
import java.util.Enumeration;
import java.util.Properties;

public class UserDirectory {
 private static final String UserDirectoryFile = "users.properties";
 private static final String UserDirectoryHeader = "${user}=${password}";

 public static UserDirectory getInstance() throws UserDirectoryException {
  if (null == userDirectory) {
   userDirectory = new UserDirectory();
  }
   return userDirectory;
 }
 
  public void setUser(String userId, String password) throws
   UserDirectoryException {
   if ( (null == userId) || (null == password)) {
    throw new UserDirectoryException();
   }try {
    p.put(fixId(userId), password);
    p.store(new FileOutputStream(UserDirectoryFile),UserDirectoryHeader);
   }catch (IOException e) {
    throw new UserDirectoryException();
   }
  }
 }

• char charAt(int index)

  returns the character at the specified location.

• int compareTo(String other)

  returns a negative value if the string comes before other in dictionary order, a positive value if the string comes after other in dictionary order, or 0 if the strings are equal.

• boolean endsWith(String suffix)

  returns true if the string ends with suffix.

• boolean equals(Object other)

  returns true if the string equals other.

• boolean equalsIgnoreCase(String other)

  returns true if the string equals other, except for upper/lowercase distinction.

• int indexOf(String str)

• int indexOf(String str, int fromIndex)

  return the start of the first substring equal to str, starting at index 0 or at fromIndex.

• int lastIndexOf(String str)

• int lastIndexOf(String str, int fromIndex)

  return the start of the last substring equal to str, starting at the end of the string or at fromIndex.

• int length()

  returns the length of the string.

• String replace(char oldChar, char newChar)

  returns a new string that is obtained by replacing all characters oldChar in the string with newChar.

• boolean startsWith(String prefix)

  returns true if the string begins with prefix.

• String substring(int beginIndex)

• String substring(int beginIndex, int endIndex)

  return a new string consisting of all characters from beginIndex until the end of the string or until endIndex (exclusive).

• String toLowerCase()

  returns a new string containing all characters in the original string, with uppercase characters converted to lower case.

• String toUpperCase()

  returns a new string containing all characters in the original string, with lowercase characters converted to upper case.

• String trim()

  returns a new string by eliminating all leading and trailing spaces in the original string.

字符串與基本數(shù)據(jù)類型的轉(zhuǎn)換間的轉(zhuǎn)換必須使用JSP中的對象函數(shù)
Boolean.getBoolean(String)
Byte.parseByte(String)
Short.parseShort(String)
Integer.parseInt(String)
Long.parseLong(String)
Float.parseDouble(String)
Double.parseDouble(String)
String.valueOF(數(shù)據(jù))


Array

eg: 

 int[] smallPrimes = {2, 3, 5, 7, 11, 13};
  int[] luckyNumbers = {1001, 1002, 1003, 1004, 1005, 1006, 1007};
  System.arraycopy(smallPrimes, 2, luckyNumbers, 3, 3);
  for (int i = 0; i < luckyNumbers.length; i++)
     System.out.println(i + ": " + luckyNumbers[i]);

1、Message.java
public class Message {

 public static void main(String[] args) {
    if (args[0].equals("-h"))
          System.out.print("Hello,");
       else if (args[0].equals("-g"))
          System.out.print("Goodbye,");
       // print the other command line arguments
       for (int i = 1; i < args.length; i++)
          System.out.print(" " + args[i]);
       System.out.println("!");

 }
}

test:
java Message -g cruel world



import java.util.*;
import javax.swing.*;
public class FirstSample {

 public static void main(String[] args) {
       String input = JOptionPane.showInputDialog
          ("How many numbers do you need to draw?");
       int k = Integer.parseInt(input);

       input = JOptionPane.showInputDialog
          ("What is the highest number you can draw?");
       int n = Integer.parseInt(input);

       // fill an array with numbers 1 2 3 . . . n
       int[] numbers = new int[n];
       for (int i = 0; i < numbers.length; i++)
       {    numbers[i] = i + 1;
       System.out.println(numbers[i]);
       }
       // draw k numbers and put them into a second array

       int[] result = new int[k];
       for (int i = 0; i < result.length; i++)
       { 
          // make a random index between 0 and n - 1
          int r = (int)(Math.random() * n);

          // pick the element at the random location
          result[i] = numbers[r];

          // move the last element into the random location
          numbers[r] = numbers[n - 1];
          n--;
       }

       // print the sorted array

       Arrays.sort(result);
       System.out.println
          ("Bet the following combination. It'll make you rich!");
       for (int i = 0; i < result.length; i++)
          System.out.println(result[i]);

       System.exit(0);

 }
}

The include Directive

The following is the syntax for the include directive:

<%@ include file="relativeURL" %>

As you can see the directive accepts a single file attribute that is used to indicate the resource whose content is to be included in the declaring JSP. The file attribute is interpreted as a relative URL; if it starts with a slash it's interpreted as relative to the context of the web application (namely a context-relative path), otherwise it's interpreted as relative to the path of the JSP that contains the include directive (namely a page relative path). The included file may contain either static content, such as HTML or XML, or another JSP page.

For example:
<%@ include file="/copyright.html"%>


Let's consider a real-world example of such a templating mechanism that utilizes the include directive to provide a consistent page layout for a web application.

Consider the following two JSP pages:

Header.jsp
    <html>
      <head><title>A Very Simple Example</title></head>
      <body style="font-family:verdana,arial;font-size:10pt;">
        <table width="100%" height="100%">
          <tr bgcolor="#99CCCC">
            <td align="right" height="15%">Welcome to this example...</td>
          </tr>
          <tr>
            <td height="75%">

Footer.jsp
           </td>
         </tr>
         <tr bgcolor=" #99CC99">
           <td align="center" height="10%">Copyright ACompany.com 2003</td>
         </tr>
       </table>
     </body>
   </html>

As you can see, Header.jsp declares the starting elements of an HTML table that is to be 100 percent of the size of the page and has two rows, whereas Footer.jsp simply declares the closing elements for the table. Used separately, either JSP will result in partial HTML code that will look very strange to a user but when they're combined using the include directive it's easy to create consistent pages as part of a web application.

Let's see just how simple this basic template mechanism is to use:

Content.jsp
    <%@ include file='./Header.jsp'%>
    <p align="center">The Content Goes Here...!!!</p>
    <%@ include file='./Footer.jsp'%>

2、
date.jsp
<html>
  <body>
    <h2>Greetings!</h2>
 <P>The current time is <%=new java.util.Date()%> precisely
  </body>
</html>

3、
dateBean.jsp
<html>
    <head><title>Professional JSP, 3rd Edition</title></head>
    <body style="font-family:verdana;font-size:10pt;">
        <jsp:useBean id="date" class="com.apress.projsp20.ch01.DateFormatBean"/>
        <h2>Today's date is <%= date.getDate() %></h2>
    </body>
</html>

或：
dateBean_getProperty.jsp
<html>
    <head><title>Professional JSP, 3rd Edition</title></head>
    <body style="font-family:verdana;font-size:10pt;">
        <jsp:useBean id="date" class="com.apress.projsp20.ch01.DateFormatBean"/>
        <h2>Today's date is <jsp:getProperty name="date" property="date"/></h2>
    </body>
</html>

dateBean_setProperty.jsp
<html>
    <head><title>Professional JSP, 3rd Edition</title></head>
    <body style="font-family:verdana;font-size:10pt;">
        <jsp:useBean id="date" class="com.apress.projsp20.ch01.DateFormatBean"/>
        <jsp:setProperty name="date" property="format"
                         value="EEE, d MMM yyyy HH:mm:ss z"/>
        <h2>Today's date is <jsp:getProperty name="date" property="date"/></h2>
    </body>
</html>

其中DateFormatBean.java:
   package com.apress.projsp20.ch01;

    import java.util.Date;
    import java.text.*;

    public class DateFormatBean {
      private DateFormat dateFormat;
      private Date date;

      public DateFormatBean() {
        dateFormat = DateFormat.getInstance();
        date = new Date();
      }

      public String getDate() {
        return dateFormat.format(date);
      }

      public void setDate(Date date) {
        this.date = date;
      }

      public void setFormat(String format) {
        this.dateFormat = new SimpleDateFormat(format);
      }
    }
例：SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");

DBPhoneLookupReuse.java
import java.io.*;
import java.sql.*;
import javax.servlet.*;
import javax.servlet.http.*;

public class DBPhoneLookupReuse extends HttpServlet {

  private Connection con = null;

  public void init() throws ServletException {
    try {
      // Load (and therefore register) the Sybase driver
      Class.forName("com.jnetdirect.jsql.JSQLDriver");
      con = DriverManager.getConnection(
        "jdbc:JSQLConnect://127.0.0.1/database=JAAS", "sa", "db_password");
    }
    catch (ClassNotFoundException e) {
      throw new UnavailableException("Couldn't load database driver");
    }
    catch (SQLException e) {
      throw new UnavailableException("Couldn't get db connection");
    }
  }

  public void doGet(HttpServletRequest req, HttpServletResponse res)
                               throws ServletException, IOException {
    res.setContentType("text/html");
    PrintWriter out = res.getWriter();

    out.println("<HTML><HEAD><TITLE>Phonebook</TITLE></HEAD>");
    out.println("<BODY>");

    HtmlSQLResult result =
      new HtmlSQLResult("SELECT UserName,Password FROM Users", con);

    // Display the resulting output
    out.println("<H2>Users:</H2>");
    out.println(result);
    out.println("</BODY></HTML>");
  }

  public void destroy() {
    // Clean up.
    try {
      if (con != null) con.close();
    }
    catch (SQLException ignored) { }
  }
}

HtmlSQLResult.java
import java.sql.*;

public class HtmlSQLResult {
  private String sql;
  private Connection con;

  public HtmlSQLResult(String sql, Connection con) {
    this.sql = sql;
    this.con = con;
  }

  public String toString() {  // can be called at most once
    StringBuffer out = new StringBuffer();

    // Uncomment the following line to display the SQL command at start of table
    // out.append("Results of SQL Statement: " + sql + "<P>\n");

    try {
      Statement stmt = con.createStatement();

      if (stmt.execute(sql)) {
        // There's a ResultSet to be had
        ResultSet rs = stmt.getResultSet();
        out.append("<TABLE>\n");

        ResultSetMetaData rsmd = rs.getMetaData();

        int numcols = rsmd.getColumnCount();
  
        // Title the table with the result set's column labels
        out.append("<TR>");
        for (int i = 1; i <= numcols; i++)
          out.append("<TH>" + rsmd.getColumnLabel(i));
        out.append("</TR>\n");

        while(rs.next()) {
          out.append("<TR>");  // start a new row
          for(int i = 1; i <= numcols; i++) {
            out.append("<TD>");  // start a new data element
            Object obj = rs.getObject(i);
            if (obj != null)
              out.append(obj.toString());
            else
              out.append("&nbsp;");
            }
          out.append("</TR>\n");
        }

        // End the table
        out.append("</TABLE>\n");
      }
      else {
        // There's a count to be had
        out.append("<B>Records Affected:</B> " + stmt.getUpdateCount());
      }
    }
    catch (SQLException e) {
      out.append("</TABLE><H1>ERROR:</H1> " + e.getMessage());
    }
  
    return out.toString();
  }
}

1、NTLM can be done with JCIFS and without HTTP. Only a few lines of code are required in the code of your servlet:

InetAddress ip = InetAddress.getByName(”192.168.0.1.”); // ip address of your windows controller
UniAddress myDomain = new UniAddress(ip);
NtlmPasswordAuthentication auth = new NtlmPasswordAuthentication(”MYDOMAIN”, “mylogin”, “mypasword”);
SmbSession.logon(myDomain, auth);

If an exception is triggered, the controller didn’t like the login and the password

2、Http方式下web.xml中filter的配置:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE web-app PUBLIC "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN" "<web-app>
 <display-name>WEB APP</display-name>
 <description>WEB APP description</description>
 <servlet>
  <servlet-name>ShowRequestHeaders</servlet-name>
  <servlet-class>coreservlets.ShowRequestHeaders</servlet-class>
 </servlet>
 <servlet-mapping>
  <servlet-name>ShowRequestHeaders</servlet-name>
  <url-pattern>/ShowRequestHeaders</url-pattern>
 </servlet-mapping>
  <filter>
    <filter-name>NtlmHttpFilter</filter-name>
    <filter-class>jcifs.http.NtlmHttpFilter</filter-class>

//import java.text.*;
//import java.util.*;

public static String addDate(String day,int x)
  {
    SimpleDateFormat format=new SimpleDateFormat("yyyy/MM/dd");
    Date date = null;
    try
    {
      date = format.parse(day);
    }
    catch (ParseException ex)
    {
      ex.printStackTrace();
    }
    if (date==null) return "";
    Calendar cal=Calendar.getInstance();
    cal.setTime(date);
    cal.add(Calendar.DAY_OF_MONTH,x);
    date=cal.getTime();
    System.out.println("3 days after(or before) is "+format.format(date));
    cal=null;
    return format.format(date);
  }

建目錄coreservlets,將兩個servlets放在這個目錄中,在coreservlet的上級目錄
運行:
javac coreservlets/HelloServlet3.java



package coreservlets;

import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;

/** Simple servlet for testing the use of packages
 *  and utilities from the same package.
 *  <P>
 *  Taken from Core Servlets and JavaServer Pages 2nd Edition
 *  from Prentice Hall and Sun Microsystems Press,
 *  http://www.coreservlets.com/.
 *  &copy; 2003 Marty Hall; may be freely used or adapted.
 */

public class HelloServlet3 extends HttpServlet {
  public void doGet(HttpServletRequest request,
                    HttpServletResponse response)
      throws ServletException, IOException {
    response.setContentType("text/html");
    PrintWriter out = response.getWriter();
    String title = "Hello (3)";
    out.println(ServletUtilities.headWithTitle(title) +
                "<BODY BGCOLOR=\"#FDF5E6\">\n" +
                "<H1>" + title + "</H1>\n" +
                "</BODY></HTML>");
  }
}




package coreservlets;

import javax.servlet.*;
import javax.servlet.http.*;

/** Some simple timesavers. Note that most are static methods.
 *  <P>
 *  Taken from Core Servlets and JavaServer Pages 2nd Edition
 *  from Prentice Hall and Sun Microsystems Press,
 *  http://www.coreservlets.com/.
 *  &copy; 2003 Marty Hall; may be freely used or adapted.
 */

public class ServletUtilities {
  public static final String DOCTYPE =
    "<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.0 " +
    "Transitional//EN\">";

  public static String headWithTitle(String title) {
    return(DOCTYPE + "\n" +
           "<HTML>\n" +
           "<HEAD><TITLE>" + title + "</TITLE></HEAD>\n");
  }

  /** Read a parameter with the specified name, convert it
   *  to an int, and return it. Return the designated default
   *  value if the parameter doesn't exist or if it is an
   *  illegal integer format.
  */
 
  public static int getIntParameter(HttpServletRequest request,
                                    String paramName,
                                    int defaultValue) {
    String paramString = request.getParameter(paramName);
    int paramValue;
    try {
      paramValue = Integer.parseInt(paramString);
    } catch(NumberFormatException nfe) { // null or bad format
      paramValue = defaultValue;
    }
    return(paramValue);
  }

  public static double getDoubleParameter
                                 (HttpServletRequest request,
                                  String paramName,
                                  double defaultValue) {
    String paramString = request.getParameter(paramName);
    double paramValue;
    try {
      paramValue = Double.parseDouble(paramString);
    } catch(NumberFormatException nfe) { // null or bad format
      paramValue = defaultValue;
    }
    return(paramValue);
  }

  /** Replaces characters that have special HTML meanings
   *  with their corresponding HTML character entities.
   */
 
  // Note that Javadoc is not used for the more detailed
  // documentation due to the difficulty of making the
  // special chars readable in both plain text and HTML.
  //
  // Given a string, this method replaces all occurrences of
  //  '<' with '&lt;', all occurrences of '>' with
  //  '&gt;', and (to handle cases that occur inside attribute
  //  values), all occurrences of double quotes with
  //  '&quot;' and all occurrences of '&' with '&amp;'.
  //  Without such filtering, an arbitrary string
  //  could not safely be inserted in a Web page.

  public static String filter(String input) {
    if (!hasSpecialChars(input)) {
      return(input);
    }
    StringBuffer filtered = new StringBuffer(input.length());
    char c;
    for(int i=0; i<input.length(); i++) {
      c = input.charAt(i);
      switch(c) {
        case '<': filtered.append("&lt;"); break;
        case '>': filtered.append("&gt;"); break;
        case '"': filtered.append("&quot;"); break;
        case '&': filtered.append("&amp;"); break;
        default: filtered.append(c);
      }
    }
    return(filtered.toString());
  }

  private static boolean hasSpecialChars(String input) {
    boolean flag = false;
    if ((input != null) && (input.length() > 0)) {
      char c;
      for(int i=0; i<input.length(); i++) {
        c = input.charAt(i);
        switch(c) {
          case '<': flag = true; break;
          case '>': flag = true; break;
          case '"': flag = true; break;
          case '&': flag = true; break;
        }
      }
    }
    return(flag);
  }
}