知识库--The Simple Container Application

The Simple Container Application

The main purpose of the application in this chapter is show how to use the default connector. It consists of two classes:

The SimpleContainer class implements org.apache.catalina.container so that it can be associated with the connector. The Bootstrap class is used to start the application, we have removed the connector module and the ServletProcessor and StaticResourceProcessor classes in the application accompanying 3.0, so you cannot request a static page.

public class SimpleContainer implements Container {
public static final String WEB_ROOT = System.getProperty("user.dir") + File.separator + "webroot";
...// other method omit
@Override
public void invoke(Request request, Response response) throws IOException, ServletException {
String servletName = ((Httpservletrequest)request).getURI();
servletName = servletName.subString(servletName.lastIndexof("/")+1);
URLClassLoader loader = null;
try{
URL[] urls = new URL[1];
URLStreamHandler streamHandler = null;
File classpath = new File(WEB_ROOT);
String repository = (new URL("file",null,classpath.getCanonicalpath() + File.separator)).toString();
urls[0] = new URL(null,repository,streamHandler);
loader = new URLClassLoader(urls);
}catch(IOException e){
System.out.println(e.toString());
}
Class myClass = null;
try{
myClass = loader.loadclass(servletName);
}catch(classNotFoundException e){
System.out.ptintln(e.toString());
}

servlet servlet = null;
try{
servlet = (Servlet)myClass.newInstance();
servlet.service((HttpServletRequest)request,(HttpServletResponse)response);
}catch(Exception e){
...
}catch(Throwable e){
...
}

}
}

Bootstrap class:

public final class Bootstrap{
public static void main(String[] args){
HttpConnector connector = new HttpConnector();
SimpleContainer container = new SimpleContainer();
connector.setContainer(container);

try{
connector.initialize();
connector.start();
System.in.read();
}catch(Exception e){
...
}
}
}

The main method associates the connector with the container by calling the connector’s setContainer method, passing the container. Next, it calls the connector’s initialize and start methods. This will make the connector ready for processing any HTTP request on port 8080.

You can terminate the application by pressing a key on the console.

Running the Application

java -classpath ./lib/servlet.jar;./….Bootstrap