.


:

:



,



( , )

:

































 

 

 

 
FAQ

RequestOutput.generate(resp, req);

⇐ 32333435363738394041 ⇒



}

}

performTask() - HttpServletRequest req HttpServletResponse resp.

/* # 5: : RequestOutput.java */

package chapt18;

import java.io.IOException;

import java.io.PrintWriter;

import java.util.Enumeration;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

 

public class RequestOutput {

public static void generate(HttpServletResponse resp,

HttpServletRequest req) {

try {

String name, value;

resp.setContentType("text/html; charset=utf-8");

PrintWriter out = resp.getWriter();

 

out.print("<HTML><HEAD>");

out.print("<TITLE></TITLE>");

out.print("</HEAD><BODY>");

out.print("<TABLE BORDER=3>");

Enumeration names = req.getParameterNames();

while (names.hasMoreElements()) {

name = (String) names.nextElement();

value = req.getParameterValues(name)[0]; /*

name = new String(name.getBytes("ISO-8859-1"), "utf-8");

value = new String(value.getBytes("ISO-8859-1"), "utf-8");

*/

out.print("<TR>");

out.print("<TD>" + name + "</TD>");

out.print("<TD>" + value + "</TD>");

out.print("</TR>");

}

out.print("</TABLE></BODY></HTML>");

out.close();

} catch (IOException e) {

e.printStackTrace();

}

}

}

resp text/html UTF-8, . out resp.getWriter(), . HttpServletRequest req Enumeration . , , . ( ) :
, , ISO-8859-1, , UTF-8. getParameterValues(name). .

chapt18,
FormRequest.class

/webapps/FirstProject3/WEB-INF/classes/chapt18

, HTML, chapt18.FormRequest. web.xml :

<servlet>

<servlet-name> MyForm </servlet-name>

<servlet-class> chapt18.FormRequest </servlet-class>

</servlet>

<servlet-mapping>

<servlet-name> MyForm </servlet-name>

<url-pattern> /testform </url-pattern>

</servlet-mapping>

URL- testform. :

. 18.2.

getParameterValues() . , , . . getParameterNames() Enumeration, , .

, . , doGet() doPost(). service() . , , , synchronized. 500 , , , .

/* # 6: :

ServletSynchronization.java */

package chapt18;

import java.io.*;

import javax.servlet.ServletException;

import javax.servlet.http.*;

public class ServletSynchronization extends HttpServlet {

//

private StringBuffer locked = new StringBuffer();

 

protected void doGet(HttpServletRequest req,

HttpServletResponse res)

throws ServletException, IOException {

performTask(req, res);

}

private void performTask(HttpServletRequest req,

HttpServletResponse res)

throws ServletException, IOException {

try {

Writer out = res.getWriter();

out.write(

"<HTML><HEAD>"

+ "<TITLE>SynchronizationDemo</TITLE>"

+ "</HEAD><BODY>");

out.write(createString());

out.write("</BODY></HTML>");

out.flush();

out.close();

} catch (IOException e) {

throw new RuntimeException(

"Failed to handle request: " + e);

}

}

protected String createString() {

//

final String SYNCHRO = "SYNCHRONIZATION";

 

synchronized (locked) {

try {

for (int i = 0; i < SYNCHRO.length(); i++) {

locked.append(SYNCHRO.charAt(i));

Thread.sleep(500);

}

} catch (InterruptedException e) {

e.printStackTrace();

}

String result = locked.toString();

locked.delete(0, SYNCHRO.length() - 1);

return result;

}

}

}

.

. 18.3. Synchronization

 

. 18.4. Synchronization

, , , .

, , Web-. , , .

API JavaMail JSP. API JavaMail , . javax.mail.Session , javax.mail.Message , javax.mail.internet.InternetAddress .

. 18.5.

J2EE zip-, http://java.sun.com/products/javamail/, mail.jar activation.jar. jar- (common/lib Tomcat). James, apache.org.

JSP, : to, from, subj

<!-- # 7: : index.jsp-->

<%@ page language="java" contentType=

"text/html; charset=UTF-8" pageEncoding="UTF-8"%>

<html><head><title>SendMail Application</title></head>

<b> </b>

< form method="post" action="sendmail" >

<table>

<tr><td><b>To(email):</b></td><td>

<input name="to" type="text" size=40> </td></tr>

<tr><td><b>From(email):</b></td><td>

<input name="from" type="text" size=40> </td></tr>

<tr><td><b>Subject:</b></td><td>

<input name="subj" type="text" size=40> </td></tr>

</table>

<hr>

<textarea name="body" type="text" rows=5 cols=45>

!</textarea>

<br>

<input type="submit" value="!">

</form>

</body></html>


.

/* # 8: :

SendMailServlet.java */

package chapt18;

import javax.mail.Message;

import javax.mail.MessagingException;

import javax.mail.Session;

import javax.mail.Transport;

import javax.mail.internet.AddressException;

import javax.mail.internet.InternetAddress;

import javax.mail.internet.MimeMessage;

import javax.activation.*;

import javax.servlet.ServletConfig;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import java.io.IOException;

import java.io.PrintWriter;

 

public class SendMailServlet

extends javax.servlet.http.HttpServlet

implements javax.servlet.Servlet {

//

private Session mailSession = null;

 

public void init(ServletConfig config)

throws ServletException {

//mailSession = Session.getDefaultInstance(System.getProperties());

final String host = "mail.smtphost";

final String port = "mail.smtpport";

// web.xml

String hostvalue = config.getInitParameter(host);

String portvalue = config.getInitParameter(port);

java.util.Properties props = new java.util.Properties();

//

props.put(host, hostvalue);

props.put(port, portvalue);

//

mailSession = Session.getDefaultInstance(props, null);

}

protected void doPost(HttpServletRequest request,

HttpServletResponse response)

throws ServletException, IOException {

//

String from = request.getParameter("from");

String to = request.getParameter("to");

String subject = request.getParameter("subj");

String content = request.getParameter("body");

if ((from == null) || (to == null)

|| (subject == null) || (content == null)) {

/*

*/

response.sendRedirect("index.jsp");

return;

}

//

(new MailSender(to, from, subject, content)).start();

//

response.setContentType("text/html; charset=CP1251");

PrintWriter out = response.getWriter();

out.println("<html><head><title>");

out.println("SendMail Application</title></head>");

out.println(" Message to <b>" + to

+ "</b> sending in progress ");

out.println(" <a href = \"index.jsp\">New message </a>");

out.println("</body></html>");

}

private class MailSender extends Thread {

private String mailTo;

private String mailFrom;

private String mailSubject;

private String mailContent;

MailSender(String mailTo, String mailFrom,

String mailSubject, String mailContent) {

setDaemon(true);

this. mailTo = mailTo;

this. mailFrom = mailFrom;

this. mailSubject = mailSubject;

this. mailContent = mailContent;

}

public void run() {

try {

//

Message message = new MimeMessage(mailSession);

//

message.setFrom(new InternetAddress(mailFrom));

message.setRecipient(Message.RecipientType.TO,

new InternetAddress(mailTo));

message.setSubject(mailSubject);

message.setContent(mailContent, "text/plain");

//

Transport.send(message);

} catch (AddressException e) {

e.printStackTrace();

System. err. print(" ");

} catch (MessagingException e) {

e.printStackTrace();

System. out. print(" ");

}

}

}

}

:

Message to [email protected] sending in progress New message

New message , index.jsp . .

web.xml :

<?xml version="1.0" encoding="UTF-8"?>

<web-app id="WebApp_ID" version="2.4" xmlns="http://java.sun.com/xml/ns/j2ee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd">

<display-name>FirstMail</display-name>

<servlet>

<display-name>

SendMailServlet</display-name>

<servlet-name>SendMailServlet</servlet-name>

<servlet-class>

SendMailServlet</servlet-class>

<init-param>

<param-name> mail.smtphost </param-name>

<param-value> mail.bsu.bsu </param-value>

</init-param>

<init-param>

<param-name> mail.smtpport </param-name>

<param-value> 25 </param-value>

</init-param>

</servlet>

<servlet-mapping>

<servlet-name>chapt18.SendMailServlet</servlet-name>

<url-pattern>/sendmail</url-pattern>

</servlet-mapping>

<welcome-file-list>

<welcome-file>index.jsp</welcome-file>

</welcome-file-list>

</web-app>

mail.smtphost mail.attbi.com.

18

Java- JSP-, :

1. : , , .

2. . .

3. , . , .

4. (, , , , , , ..) , .

5. () ().

6. (, , ..) .

7. (, , ..)
.

8.
, . :

) ; ) , ; ) , 0ºC; ) .

9. 21.

10. 34 .

11. .
.

12. . .

13. . , .
.

14. . .

15. -.

16. , 3 , 80 .

B

4 . , , IP- .

18

18.1.

init() URL? ( )

1) ServletConfig.getInitParameter("URL");

2) getServletConfig().getInitParameter("URL");

3) this.getInitParameter("URL");

4) HttpSerlet.getInitParameter("URL");

5) ServletContext.getInitParameter("URL").

18.2.

FirstServlet HTML-?

<html><body>

<a href="/FirstProject/FirstServlettest">OK!</a>

</body><html>

<url-pattern> web.xml :

<url-pattern>/FirstServlettest</url-pattern>

1) doGet();

2) doGET();

3) performTask();

4) doPost();

5) doPOST().

18.3.

init()

1) ;

2) , ;

3) , ;

4) ;

5) ;

6) , , .

18.4.

getResource()
getResourceAsStream() ServletContext?

1) ServletContext ;

2) String InputStream;

3) URL InputStream;

4) URL StreamReader.

18.5.

javax.servlet?

1) ServletRequest;

2) ServletOutputStream;

3) PageContext;

4) Servlet;

5) ServletContextEvent;

6) .

18.6.

, ? ( )

<HTML><BODY>

<FORM action="/com/MyServlet">

<INPUT type="file" name="filename">

<INPUT type="submit" value="Submit">

</FORM></BODY></HTML>

1) request.getParameterValues("filename");

2) request.getAttribute("filename");

3) request.getInputStream();

4) request.getReader();

5) request.getFileInputStream().

 

 

 
19

Java Server Pages

Java Server Pages (JSP) Sun Microsystems, .

, JSP HTML, XML, WML .

/ JSP, Web-:

1) , : , JSP, java-;

2) , HTML, JavaScript, ..

, HTTP-, (Servlet Engine) .

: Web-, , Web-, .

JSP- :

d) .

Web- Web- .

d) .

JSP-, Java, , JSP Web-. JSP .

e) .

JavaBeans Enterprise JavaBeans (EJB) , Web-.

f) .

JSP , , JSP JavaScript, HTML-. JavaScript , HTML-. JavaBean .

, JSP , JavaBean JSP.

Java Server Pages ( HTML, JSP ) -. , , JSP. , JSP/Servlet-, thin-client ( ), .

JSP HTML-, JSP-, action-, JSTL . JSP 2.0 :

<%@ %> JSP.

<%! %> Java , expression- . out , .

<% %> Java- JSP-. . , , . Java _jspService() .

<%= %> Java, , String out.

<%-- JSP- --%>, JSP- .

action

, , . JSP 2.0. JSP :

1) jsp:declaration , <%!... %>;

2) jsp:scriptlet , <%... %>;

3) jsp:expression , <%=... %>;

4) jsp:text ;

2 jsp:useBean Java Bean. , page (), request (), session () application (). , , id ( ), scope ( ), class ( ), type ( class).

<jsp:useBean id=ob

scope=session

class=test.MyBean />

ob MyBean, . JavaBean , field, field, , , setField(type value), getField().

package test;

public class MyBean {

private String field = " ";

public String getField() {

return info;

}

public void setField(String f) {

field = f;

}

}

5) jsp:setProperty name . property *, JavaBean , - (setter-) :

<jsp:setProperty name=ob

property=field

value= />

e) jsp:getProperty , out:

<jsp:getProperty name=ob property=field />

f) jsp:include :

<jsp:include page= URL

flush=true/>

g) jsp:forward :

<jsp:forward page= URL />

h) jsp:plugin <OBJECT> <EMBED>, , Java Bean.

i) jsp:params jsp:plugin.

6) jsp:param , forward, include, plugin.

7) jsp:fallback , , . plugin.

:

<jsp:plugin type=bean | applet

code=test.com.ReadParam

width=250

height=250>

<jsp:params>

<jsp:param name=bNumber value=7 />

<jsp:param name=state value=true />

</jsp:params>

<jsp:fallback>

<p> unable to start plugin </p>

</jsp:fallback>

</jsp:plugin>

5 11, , , /WEB-INF, /classes.

<jsp:attribute>, <jsp:body>, <jsp:invoke>, <jsp:doBody>, <jsp:element>, <jsp:output> .

JSP-

JSP- JSP- XML-, , JSP, JSTL, XML- JSP. JSP- , . JSP- .jspx.

taglib JSP:

<%@ taglib uri="http://java.sun.com/jsp/jstl/core"

prefix="c"%>

JSP-:

<jsp:root xmlns:c="http://java.sun.com/jsp/jstl/core"/>

page JSP:

<%@ page contentType="text/html"%>

JSP-:

<jsp:directive.page contentType="text/html" />

include JSP:

<%@ include file="file.jspf"%>

JSP-:

<jsp:directive.include file="file.jspf" />

, JSP- JSP-.

<!-- # 1: jsp-: page.jsp -->

<%@ page contentType="text/html; charset=Cp1251" %>

<html><head><title>JSP-</title></head>

<%! private int count = 0;

String version = new String("J2EE 1.5");

private String getName(){ return "J2EE 1.6";} %>

<% out.println(" count: "); %>

<%= count++ %>

<br/>

<% out.println(" count : " + count); %>

<br/>

<% out.println(" version: "); %>

<%= version %>

<br/>

<% version=getName();

out.println(" version: " + version); %>

</html>

JSP- , , .

<!-- # 2: jsp-: page.jspx -->

<jsp:root xmlns:jsp="http://java.sun.com/JSP/Page"

version="2.0">

<jsp:directive.page contentType=

"text/html; charset=UTF-8" />

<html><body>

<jsp:declaration>

private int count = 0;

String version = new String("J2EE 1.5");

private String getName(){ return "J2EE 1.6";}

</jsp:declaration>

<jsp:scriptlet>

out.println(" count: ");

</jsp:scriptlet>

<jsp:expression>

count++

</jsp:expression>

<br />

<jsp:scriptlet>

out.println(" count :"

+ count);

</jsp:scriptlet>

<br/>

<jsp:scriptlet>

out.println(" version: "); </jsp:scriptlet>

<jsp:expression> version </jsp:expression>

<br/>

<jsp:scriptlet> version=getName();

out.println(" version: " + version);

</jsp:scriptlet>

</body></html>

</jsp:root>

JSP-.

JSTL

JSP-, , action ( ) , JSTL (JSP Standard Tag Library). JSTL Java- JSP. , , , -, Java.

JSTL 1.1.2 (jstl-1.1.2.jar standard-1.1.2.jar) c apache.org. /lib . xmlns root ( JSP- taglib uri="") , , JSP- JSTL. uri ( xmlns) ( c.tld). JSP JSTL, :

<!-- # 3: jsp-: simple.jspx -->

<jsp:root xmlns:jsp="http://java.sun.com/JSP/Page"

xmlns:c=http://java.sun.com/jsp/jstl/core

version="2.0">

<jsp:directive.page contentType=

"text/html; charset=Utf-8"/>

<html><body>

<c:out value="Welcome to JSTL"/>

</body></html>

</jsp:root>

<c:out/> value JspWriter.

JSTL :

- Expression Language, ;

- , , ;

- (URL) ;

- JSP;

- ;

- XML, .

Expression Language

JSTL Expression Language (EL). EL , (page, request, application) .

EL ${ }.

JSP 2.0 / JSTL 1.1, EL JSP . web-app 2.4 isELIgnored true. page true.

EL- , PageContext.findAttribute( ). : page (PageContext), request (HttpServletRequest), session (HttpSession), application (ServletContext). , null. paramValues requestHeaders.

, , , JavaBeans, , List, Map, Array . EL . []. . :

<c:out value=${student.name}/>

<!-- # 4: jsp-: simple2.jspx -->

<jsp:root xmlns:jsp="http://java.sun.com/JSP/Page"

xmlns:c="http://java.sun.com/jsp/jstl/core"

version="2.0">

<jsp:directive.page contentType=

"text/html; charset=Utf-8"/>

<html>

<head><title> EL</title></head>

<body>

<c:set var="login" value="" scope="page"/>

<c:out value="${login} in Rio"/>

<br/>

<c:out value=" : ${login.bytes} "/>

</body></html>

</jsp:root>

. , . login.bytes Java login.getBytes().

:

in Rio
: [B@edf730

EL .

:

:

== ( eq), != ( neq), < ( lt), > ( gt), <= ( le), >= ( ge).

: +, -, *, / ( div), % ( mod).

: && ( and), || ( or),! ( not).

empty null, . . , .

:

<c:if test=${ not empty user and user.name neq guest}>

User is Customer.

</c:if>

⇐ 32333435363738394041 ⇒


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: 2016-04-03; !; : 1167 |

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==> ...

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