Configuration of JSP, Servlet, and JavaBean environments in Tomcat
I often see jsp beginners asking how to configure jsp, servlet, and bean in tomcat. So I summarized how to configure jsp, servlet, and ben in tomcat, hoping to help beginners.
I. Development environment configuration
Step 1: Download j2sdk and tomcat: to the sun official site (http://java.sun.com/j2se/1.4.2/download.html) download j2sdk, pay attention to download the version of Windows Offline Installation SDK, at the same time it is best to download J2SE 1.4.2 Documentation, then go to the tomcat official site (http://www.apache.org/dist/jakarta/tomcat-4/) to download tomcat (download the latest version of tomcat 4.1.x );
Step 2: install and configure your j2sdk and tomcat: execute the j2sdk and tomcat installation programs and install them according to the default settings.
1. after installing j2sdk, you need to configure the environment variables, choose my computer> Properties> Advanced> environment variables> System variables to add the following environment variables (assuming your j2sdk is installed in c: j2sdk1.4.2 ):
JAVA_HOME = c: j2sdk1.4.2
Classpath =.; % JAVA_HOME % libdt. jar; % JAVA_HOME % libtools. jar; (..; it must not be less, because it represents the current path)
Path = % JAVA_HOME % bin
Then, you can write a simple java program to test whether J2SDK has been installed successfully:
Public class Test {
Public static void main (String args []) {
System. out. println ("This is a test program .");
}
}
Save the above program as a file named Test. java.
Then open the command prompt window, cd to the directory where your Test. java is located, and then type the following command
Javac Test. java
Java Test
If This is a test program is printed, the installation is successful. If This is not printed, you need to carefully check your configuration.
2. after Tomcat is installed, add the following environment variables to my computer> Properties> Advanced> environment variables> System variables (assuming your tomcat is installed in c: tomcat ):
CATALINA_HOME = c: tomcat
CATALINA_BASE = c: tomcat
Modify the classpath in the environment variable, and append servlet. jar under commonlib under the tomat installation directory to the classpath. The modified classpath is as follows:
Classpath =.; % JAVA_HOME % libdt. jar; % JAVA_HOME % libtools. jar; % CATALINA_HOME % commonlibservlet. jar;
Start tomcat and access http: // localhost: 8080 in IE. If you see the welcome page of tomcat, the installation is successful.
Step 3: Create your own jsp app Directory
1. Go to the webapps Directory of the Tomcat installation directory, and you can see the tomcat built-in directories such as ROOT, examples, and Tomcat-docs;
2. Create a directory named myapp under the webapps directory;
3. Create a directory WEB-INF under myapp, note that the directory name is case sensitive;
4. Create a file web. xml under the WEB-INF with the following content:
<? Xml version = "1.0" encoding = "ISO-8859-1"?>
<! DOCTYPE web-app
PUBLIC "-// Sun Microsystems, Inc. // DTD Web Application 2.3 // EN"
Http://java.sun.com/dtd/web-app_2_3.dtd>
<Web-app>
<Display-name> My Web Application </display-name>
<Description>
A application for test.
</Description>
</Web-app>
5. Create a test jsp page under myapp. The file name is index. jsp. The file content is as follows:
<Html> <body> <center>
Now time is: <% = new java. util. Date () %>
</Center> </body> 6. Restart Tomcat
7. Open the browser and enter http: // localhost: 8080/myapp/index. jsp to view the current time.
Step 4: create your own Servlet:
1. Use the editor you are most familiar with (it is recommended to use java ide with syntax check) to create a servlet program named Test. java. The file content is as follows:
Package test;
Import java. io. IOException;
Import java. io. PrintWriter;
Import javax. servlet. ServletException;
Import javax. servlet. http. HttpServlet;
Import javax. servlet. http. HttpServletRequest;
Import javax. servlet. http. HttpServletResponse;
Public class Test extends HttpServlet {
Protected void doGet (HttpServletRequest request, HttpServletResponse response)
Throws ServletException, IOException {
PrintWriter out = response. getWriter ();
Out. println ("Out. flush ();
}
}
2. Compile
Put Test. java under c: test and compile it with the following command:
C: Test> javac Test. java
Then a compiled servlet File: Test. class will be generated under c: Test.
3. Cut the structure testTest. class to % CATALINA_HOME % webbench myappweb-INFclasses, that is, cut the test directory to the classes Directory. If the classes directory does not exist, create a new one. Currently, webbench myappweb-INFclasses has the file directory structure testTest. class.
4. Modify the webappsmyappWEB-INFweb.xml and add servlet and servlet-mapping
The edited web. xml is shown as follows, and red indicates the added content:
<? Xml version = "1.0" encoding = "ISO-8859-1"?>
<! DOCTYPE web-app
PUBLIC "-// Sun Microsystems, Inc. // DTD Web Application 2.3 // EN"
Http://java.sun.com/dtd/web-app_2_3.dtd>
<Web-app>
<Display-name> My Web Application </display-name>
<Description>
A application for test.
</Description>
<Servlet>
<Servlet-name> Test </servlet-name>
<Display-name> Test </display-name>
<Description> A test Servlet </description>
<Servlet-class> test. Test </servlet-class>
</Servlet>
<Servlet-mapping>
<Servlet-name> Test </servlet-name>
<Url-pattern>/Test </url-pattern>
</Servlet-mapping>
</Web-app>
In this section, servlet declares the Servlet you want to call, while servlet-mapping maps the declared servlet to the address/Test.
5. Restart Tomcat, start the browser, and enter http: // localhost: 8080/myapp/Test. If This is a servlet test, the servlet is successfully written.
Note: You must restart Tomcat after modifying web. xml and adding a new class.