Other common JSP development environments

Summary: JSWDK and Tomcat are favored by more and more JSP learners due to the small amount of resources required for running and their ease of use.
However, in the whole JSP world, they are not a standalone. There are many server software supporting JSP, which are mainly used in the commercial field, among them, the most important is Allaire Jrun, IBM Websphere, and BEA Weblogic.

1. Allaire Jrun

Allaire's JRun is a Java engine with the widest applicability. It is used to develop and implement server-side Java applications written by Java Servlets (JSP) and JavaServer Pages.
JRun is the first commercial product that fully supports JSP 1.0 specifications. Currently, Jrun has three versions, and more than 80,000 developers around the world use JRun, to add the server-side Java function to their existing Web servers. The Web servers include Microsoft IIS, Netscape Enterprise Server, and Apache. JSP is a powerful server-side technology. It is a complete set of Rapid Application Development systems used to create complex Web applications.

Product details

JRun is an advanced engine for developing and implementing server-side Java. We can use Jrun to run Java Servlets. There are two ways to run Java Servlets: Expand your Web server or use the built-in JRun Web server. By using servlets as an extensible and fully-defined Java component model throughout the environment, we can develop and implement complex applications more conveniently and quickly, it is more economical to maintain.
JRun allows you to start developing and testing Java applications. It can accept up to five concurrent connections (standard) and:

1. includes all Java Servlet APIs
2. Support for assumerver Pages (JSP)
3. Support for all major Web servers and computer platforms
4. JRun Pro is able to load large volumes of traffic in the production environment, helping you implement applications, services, or Web sites (including Intranets ). JRun Pro supports unlimited concurrent connections
5. run multiple Java virtual machines, including multiple concurrent Java virtual machines (JVM ).
6. Provides a remote management applet and a remote and Distributed Management applet.
7. JRun Pro Unlimited includes all JRun Pro functions. In addition, it can run Unlimited and concurrent JVMs.

JRun Functions

By using Java technology, you can add the server-side Java functions on the existing Web Server. JRun supports Microsoft IIS, Personal Web server, Netscape Enterprise, FastTrack, and Apache Web servers, O 'Reilly's WebSite and StarNine's WebSTAR.
JRun can be run independently based on its built-in JRun Web Server. Using server-side Java, users can develop complex commercial application systems. Most importantly, because of the independence of the servlets platform, simpler development, faster implementation, and more economical maintenance costs, it becomes a Common Gateway Interface (CGI) or an excellent alternative to Perl scripts.
In addition, JRun 2.3 can fully implement the latest Java Servlet API. At the same time, JRun can also take advantage of many advanced functions in Java Web Server. Some important JRun2.3 functions are listed as follows:

1. Fully supports Java Servlet API version2.1
2. Full support for assumerver Pages (JSP) 1.0 draft spec
3. Dynamic taglets
4. Provide ready-to-use templates
5. Edit the page
6. dynamic-servlet overload
7. Servlet-initialization attributes
8. Servlet connection and filtering
9. Support for multiple hosts (virtual hosts)
10. Tag support
11. Task tracking
12. Installation Wizard
13. Complex Swing-based management applications
14.100% pure Java and fully cross-platform
15. can run on any Java Virtual Machine
16. Run a maximum of five Java Virtual machine (JRun Pro)
17. Run on an Unlimited number of Java Virtual machines (JRun Pro Unlimited)
18. Remote Management (JRun Pro)

Technical advantages

Java Servlets is an independent cross-platform server-side program written by Java Servlet API-Java platform. Java Servlets has the powerful power of "writing once and running anywhere" and provides network transmission security and good scalability for server applications. Servlets can replace traditional server-side applications and extensions written in Perl, C/C ++, or other languages. Using Servlet as a scalable and well-defined cross-platform environment, users can easily develop and quickly implement complex applications on the server side and save maintenance costs. (Servlets can be deployed on cheap Windows NT machines)
Using existing mature server technologies, such as combining servlets with Web servers, you can avoid platform limitations and complexity in specific server configurations when writing complex applications. With Servlets, developers no longer have to worry about the internal working methods of the server. The internal classes of the servlets API can control all the resources such as Form data, server header, and cookies.
The biggest difference between existing server applications and servlets is performance. Run an independent JVM on the server. Once called, The servlet is loaded. It will not be loaded again until the servlets changes. A modified servlet can be automatically loaded without restarting the server or application. Because the servlet always stays in the memory, the loading speed is extremely fast. Static or permanent information can be shared through multiple active Servlets, and information can be shared among multiple users. Servelet is also modular. They can be used together to complete a specific task. Servlets can communicate with each other.

Web Server supported by JRun:

1. Microsoft's Internet Information Server (IIS) and Personal Web Server (PWS)
2. Netscape's Enterprise and FastTrack Servers
3. Apache
4. 'Reilly's WebSite Pro
5. StarNine's WebSTAR
6. Novell Netware 5 (Novonyx)

Ii. Websphere

WebSphere is an Internet infrastructure software. It can help enterprises develop, deploy, and integrate next-generation e-commerce applications, such as B2B e-commerce applications. With enterprise-level transaction processing, WebSphere can support all business applications from a single Web release. WebSphere has changed the relationship management between the enterprise and its customers, partners, and employees.

FAQs about Websphere

Q: How can a Web application pick out a new class file that does not belong to a servlet or EJB?
A: When configuring a Web application, specify the application class path that contains the servlet and its non-servlet Java components. The Class Loader monitors the application class path. Once it detects that the loaded servlet has been updated, it reloads all Java components in the class path of the application. On the WebSphere 3 console, you can use the "topology" label to access your Web applications, such as default_app. Specify the class path (the class path that can be reloaded) in the "advanced" label ). These classes should physically reside in the path specified here.

Q: Why does the ClassNotFound error occur when I want to call a class in the jar file?
A: When you want to call a class in the jar file, make sure that the full path of the jar file is included in the class path.

Q: What is the concept of model and clone in WebSphere?
A: You can create an Application Template called a model when you want to create almost identical copies of applications deployed in the same WebSphere Application Server. If you deploy copies of these applications, these copies are called clones. This technique is used for server workload management.

Q: Can I clear log files on my WebSphere server without stopping the application server?
A: No. You cannot delete or edit log files while the application server is running. If you do this, the application server stops writing logs. The AIX and Solaris platforms allow you to edit or delete log files without any error messages. However, the application server stops using log files. Windows NT platform will send you a message: this file is being used by another process. We recommend that you stop the application server, delete or rename or move the log, and restart the application server. If the log file does not exist when the application server starts, it creates the log files.

Q: Where should I specify the class to be loaded only once when the server is started?
A: When you install this product, the application server class path is automatically set. The default settings of the class path include all the application server APIs (JAR files in the AS_install_rootlib directory ). When the application server starts, the system class loader automatically loads classes in the class path of the application server. These classes cannot be reloaded. You can also specify a class path in the command line parameters on the general page of the application server to pass the class path to the JVM of the application server.

Q: Because my DB2 user ID and password are different from those specified during WebSphere installation, my WebSphere Application Server cannot be started. How can I change the user ID and password without re-installing WebSphere?
A: You can change the user ID and password of the database on the WebSphere Application Server by changing the following lines in the admin. config file:

Com. ibm. ejs. sm. adminServer. dbUser = db2userid
Com. ibm. ejs. sm. adminServer. dbPassword = db2password

Alternatively, you can create another user in the database so that the user ID and password are the same as those in WebSphere.

Q: How to protect an HTML page (assuming security is configured )?
A: perform the following steps:
1. Create an enterprise application.
2. Assign permissions to enterprise applications (which access permissions each group has ).
3. Create a resource, that is, the URI of the HTML file.
4. Add resources to enterprise applications.
5. Specify a security ing for this resource.

Q: Why does an error occur when I access the created JSP?
A: Make sure that you have correctly specified the Web Application Path (the content you typed in the browser) and the file system path (where the Web application looks up ). The file system path is the document root directory and the Web application class path (under the advanced level. The document root directory controls where HTML and JSP files can be found. Class path control servlet (if servlet can be loaded by class name ).

Q: Does WebSphere Connection Manager support database stored procedures?
A: Yes. WebSphere Application Server supports the JDBC model. This model provides the function of optimizing database access. Using database stored procedures is one of the functions. WebSphere Application Server extends the JDBC function by providing the com. ibm. db. CallableStatement class in ConnectionManager to access the stored procedure.

Q: What is the name of the database table that WebSphere Application Server uses to store user summary information?
A: The table name is User_Profile_Table, which is located in the WAS database.

Q: Why do I get the error SQL1046N when I access the database and execute a servlet using WebSphere Connect Manager (Data Source): The authorization ID is invalid?
A: This error may occur due to several reasons:
1. the user identity is not authorized to connect to the database.
2. Connection to the specified user identity is not authorized to execute the specified function.
3. The "ibm ws AdminServer" service "Startup-Log on as" parameter is defined as "System Account" or "This Account" that the user does not have the appropriate permissions ".
4. This error is returned when servlet or EJB implements the getConnection method without passing the user ID and password. The getConnection method uses the user ID and password defined in the environment that implements servlet or EJB routines.

To solve this error:

1. Specify the authorized user ID and password to connect to the database.
2. Ensure or grant the user identity permission to perform specific functions.
3. If you are passing the user ID and password to the getConnection method, make sure that the correct value is being passed and the variables are defined in the class. The variables are passed through the ResourceBundle attribute file.
4. If you are not passing the user ID and password to the getConnection method, make sure that the "ibm ws AdminServer" service "Startup-Log on as" parameter specifies an authorized user.

Q: How do I control the ports used by WebSphere?
A: The WebSphere administration server uses two ports: The bootstrap port and the LSD port. By default, the bootstrap port is 900 and the LSD port is 9000. If you want to run WebSphere as a root user on UNIX, you must change the bootstrap port. If you encounter a port conflict with port 9000, you must change the LSD port. Edit admin. config File and add the following attributes to control the ports: com. ibm. ejs. sm. adminServer. lsdPort = 9005 (default value: 9000) com. ibm. ejs. sm. adminServer. bootstrapPort = 9002 (default value: 900)

Q: How can I avoid invalid sessions when using the WebSphere Administration console?
A: In the Session Manager (in the servlet engine), click the "intervals" tab. Enter the value "-1" in the "invalid time" field ". This will ensure that the session will not be invalid.

Q: How does WebSphere Application Server communicate with the Web Server?
A: WebSphere Application Server uses the OSE (Open Servlet Engine) to communicate with the Web Server.

Q: How do I change the WebSphere class path?
A: You can add a class path to the Attribute Table of WebSphere Application Server. To replace the class path, click? Quot; environment field on the general tab to start the attribute environment editor. In this editor, change this path or other environment variables. To add a class path, enter the class path in the "command line arguments" field.

Q: Why does it get an error when starting WebSphere: port 9000 is in use?
A: port 9000 is the default port used to manage the server location waiting process. Many system resources (including AIXX-windows Manager) also use port 9000. If you run. /startupServer. THE sh command displays the error message "port 9000 is being used-select another port". The Management Server process cannot be started because port 9000 is being used by the aix x-windows Manager. You can specify the-lsdPort option on the command line of the Management Server to change the port listening to the waiting process of the location service, or in the admin. config file (located in the directory on Windows NT) Bin; in UNIX In/bin), set the com. ibm. ejs. sm. adminServer. lsdPort attribute.

Q: I want to store the WAS management information center database in an Oracle database on another machine. What database software should I install on the machine where WebSphere Application Server is to be installed?
A: You need to install the Oracle client on the machine on which WebSphere Application Server is to be installed, and configure the Oracle client to communicate with the remote Oracle Server. During WebSphere installation, you specify the path (for example, x: OracleOra8i) of the main directory of the Oracle client on the local machine ).

Q: How can I solve the NoClassDefFound Exception error when deploying EJB to the WebSphere container?
A: The NoClassDefFound error indicates that the deployment tool fails to find one or more support classes that are deployed or configured to EJB in WebSphere. To solve this exception, add or attach the full jar file path with the jar name to the application server class path with the application server command line-classpath parameter.

Q: Do I need to restart WebSphere and Web servers if I modify a servlet?
A: No. As long as you compile it, WebSphere (version 2.02 or later) will be able to automatically load new class files.

　　FAQs about Websphere Studio

Q: Can I use the WebSphere Studio JavaBean Wizard to create servlet, output JSP, and input HTML from an EJB?
A: You should create an access bean for ejb in the VisualAge for Java environment. Select a Java bean wrapper when creating an access bean. Now you can use this access bean in the WebSphere Studio JavaBean Wizard to create a servlet, output JSP, and input HTML. If the VisualAge for Java environment is not used in your EJB development, you must write a client JavaBean to access the EJB and use the JavaBean in WebSphere Studio.

Q: I have a. jsp file that can be run in the WebSphere test environment. Why cannot this file be run in WebSphere Application Server?
A: The reason is that WebSphere Application Server is configured to run with JSP 1.0, and WebSphere Studio is configured to generate JSP of version 0.91. To solve this problem, change the JSP version generated in WebSphere Studio: Right-click the project you are working on in WebSphere Studio and select the advanced tag under properties. In the attribute list, select JSP and Version 1.0.

Q: How do I create a custom release stage in WebSphere Studio?
A: highlight "projects" in the toolbar and select "mimize publishing stage" from the drop-down menu ". In this window, enter the stage name and select "Add ".

Q: When I drag the bean (class or jar) file to the WebSphere Studio page designer, a JSP: useBean dialog box should pop up. But every time a small application dialog box is displayed, how does one display the JSP: useBean dialog box?
A: On the WebSphere Studio page designer toolbar, select Tools and then select options. In the Options dialog box, change "HTML element generated for a dropped Java file" from an application to JSP: useBean.

Q: In WebSphere Studio, how does one switch between the test and the product server?
A: On the WebSphere Studio toolbar, select a project and highlight the release phase. You can select a test server or product server.

Q: How do I define the release target in WebSphere Studio?
A: In the WebSphere Studio release window, the server that you want to define the release target is highlighted. Right-click the target and select Properties. In the Properties window, click "define publishing targets ". In the release target window, you can add, edit, or delete a release target.

Q: How do I start a new (empty) HTML page in WebSphere Studio?
A: To create a new (empty) HTML page in WebSphere Studio, click select, insert, and file )". When the insert file dialog box appears, select empty HTML. Select "OK" under the file name )". You can rename an HTML file.

Q: In WebSphere Studio, how does one disable the automatic correction function for HTML syntax errors?
A: On the WebSphere page designer toolbar, select Tools and then select options. Remove the "correct HTML syntax errors automatically" selected status from the regular tag in the options window.

Q: How can I exchange files between VisualAge for Java 3.0 and WebSphere Studio 3.0?
A: make sure that both VAJ and WebSphere Studio are running. In the Visual Age for Java environment, find the workbench menu bar and click windows and options ). In the Options dialog box, expand visual composition and select remote access to tool API ". In this process, select the push button to start "remote access to tool API ". Switch to WebSphere Studio workbench and select a project or folder. The project or folder will load the files you copied from the Visual Age for Java environment. Right-click the context menu of the project or folder and select insert and file )". Select "tab" and "from external source )". In the supplier area, select VisualAge for Java. To select a Java file for calling, Click Browse.

Q: Which group development support can be used in WebSphere Studio?
A: When a development team develops a Web project, each team member can install a set of WebSphere Studio on his or her machine. The Group can use shared libraries online to maintain the components of the project. The workbench of WebSphere Studio maintains the check/check status of each component and displays the status of each component. The team can also use the commonly used test Web site and product release Web site for maintenance in the release window.

Q: Why does the. Java file need to be transferred from WebSphere Studio to VisualAge? Why is there an error: A call error occurs when the file is sent to Visualage for Java (compilation error detection )?
A: This problem is caused by calling the project's closed version. To create a project's "open edition", perform the following operations: select a project in VisualAge. In the drop-down list, right-click and select? Quot; manage ". Select "create open edition ".

Q: Where is the port number of the VisualAge for Java remote access to tool API stored?
A: The port number is stored in In the toolPort. properties file in the ivjtoolstooldatacom-ibm-ivj-toolserver directory. The tool server updates the file every time the server is started or shut down.

Q: What types of operations can be transferred between the WebSphere Studio 3.0 and VisualAge for Java 3.0 workspaces?
A: The following operations can be performed between the WebSphere Studio 3.0 and VisualAge for Java 3.0 workspaces:

Add from VAJ (Add from VAJ)
Update from VAJ (Update from VAJ)
Send to VAJ (Send to VAJ)
Editing in VAJ (edit in VAJ)
Consuming beans created in VAJ (use the beans created in VAJ)

Q: How does WebSphere Studio determine the location where VisualAge for Java is installed?
A: After WebSphere Studio retrieves the CurrentVersion subkey from the system registry after VisualAge for Java is installed, the version number is used to find the VAJ installation directory. The system registry sub-key "directory" (in HKEY_LOCAL_MACHINE, software, IBM, VisualAge for Java, 3.0, install) contains the VAJ installation directory information.

Q: What functions does VisualAge for Java remote access to tool API support WebSphere Studio?
A: If WebSphere Studio 3.0 detects that the VisualAge for Java software is installed, it will install some servlets on the server. WebSphere Studio uses HTTP to connect these Servlets to control file transmission between WebSphere Studio and VisualAge for Java software products.

Q: We have installed WebSphere Studio 3.0 on two different machines in the LAN. Why can't we open the project files created from another machine on one machine? Information shows that some files have been lost, invalid, or damaged.
A: If you want to access a project on a machine on the LAN, do not select the ing drive or absolute path of the project (for example, x: WebSphereStudioprojectsprojectname ), select the network path (for example, machinenamewebspherestudioprojectsprojectname) through network neighbors ). In this way, you can open the project file (. wao) from another machine in the LAN ).

Q: In WebSphere Studio 3.0, can any file of the project be opened without being checked out?
A: Yes. The file is read-only.

Q: In Websphere Studio, how do I set all project files to publish files?
A: highlight the project folder, select edit, and set it to publish.

Q: I used the WebSphere Studio SQL Wizard to create an insert statement in the insert tag, and typed the parameter name in the value column. Why does the parameter request not appear when I run the SQL statement?
A: Do you need to use the parameter button to play? Quot; create a new parameter "panel. The parameter name must be specified to be correctly displayed in the SQL statement.

Q: How can I combine the fields generated by the wizard in JSP with the JSP provided by the content provider?
A: The assumerver Pages (JSP) can be edited in the WebSphere Studio page designer. In the page designer, you can select between Two JSPs, copy and paste fields. It can be done in the regular mode or in the HTML source code mode.

　　FAQs about Websphere Performance Pack

Q: What is IBM WebSphere performance pack high-speed cache manager?
A: The IBM WebSphere performance pack express cache manager is a cost-effective proxy server for Small and Medium device devices. It uses IBM Web Traffic Express technology to provide transparent proxy for HTTP requests and can be applied in Windows NT and Linux environments.

Q: When running the eNetwork scheduler to achieve load balancing, what problems will occur if the machine running the program fails?
A: If the Server Load balancer is in process and the machine running the eNetwork scheduler fails, your website may not be accessible. With high availability, the IBM eNetwork scheduler can configure backup scheduling programs for another machine to prevent access failures on the machine that runs the master scheduler.

Iii. BEA WebLogic

To learn a set of systems, we must first understand its structure. Now we will briefly introduce some of the structures and features of WebLogic.
Most WebLogic configurations are in weblogic. properties, as long as you carefully study this file, you can clearly understand some of the structure and characteristics of WebLogic, the following is the weblogic. some configuration items in the properties file are described as follows:
Weblogic.httpd.doc umentRoot = public_html/
This is the root directory of the WebLogic WEB server, that is, the directory/weblogic/myserver/public_html/
Weblogic. password. system = sdfjkdshfds
This is to set the administrator password.
Weblogic. Systems. listenPort = 7001
This is the WEB server port for WebLogic.
Weblogic. httpd. servlet. classpath =/weblogic/myserver/servletclasses
Set the Servlet storage path.

About Servlet

For security purposes, WebLogic running in WebLogic must be in weblogic. properties, for example, Servlet http: // localhost: 7001/helloWorld, which is in weblogic. the registration items in properties are:
Weblogic. httpd. register. helloWorld = examples. servlets. HelloWorldServlet
Actually, the actual path of this Servlet is
/Weblogic/myserver/servletclasses/examples/servlets/HelloWorldServlet. class
Check the registration items in weblogic. properties and the path of the HelloWorldServlet. class file. It is not difficult to find out the rules of registering Servlet.
There are several Servlet registration items in weblogic. properties:

Weblogic. httpd. register. AdminEvents = admin. AdminEvents
Weblogic. httpd. register. AdminClients = admin. AdminClients weblogic. httpd. register. AdminConnections = admin. AdminConnections weblogic. httpd. register. AdminJDBC = admin. AdminJDBC
Weblogic. httpd. register. AdminLicense = admin. AdminLicense
Weblogic. httpd. register. AdminMain = admin. AdminMain
Weblogic. httpd. register. AdminProps = admin. AdminProps
Weblogic. httpd. register. AdminRealm = admin. AdminRealm
Weblogic. httpd. register. AdminThreads = admin. AdminThreads weblogic. httpd. register. AdminVersion = admin. AdminVersion

This is the Servlet used by the Administrator to manage WebLogic. Access http: // localhost: 7001/AdminMain through URL. In the displayed authentication dialog box, enter system and. password. system = password, you can go to the WebLogic Web management interface for management.