Class Webserver

  • Direct Known Subclasses:
    AppletServer

    public class Webserver
    extends java.lang.Object
    A web server for running sample programs.

    This enables a Java program to instrument class files loaded by web browsers for applets. Since the (standard) security manager does not allow an applet to create and use a class loader, instrumenting class files must be done by this web server.

    Note: although this class is included in the Javassist API, it is provided as a sample implementation of the web server using Javassist. Especially, there might be security flaws in this server. Please use this with YOUR OWN RISK.

    • Field Summary

      Fields 
      Modifier and Type Field Description
      java.lang.String debugDir
      If this field is not null, the class files taken from ClassPool are written out under the directory specified by this field.
      java.lang.String htmlfileBase
      The top directory of html (and .gif, .class, ...) files.
    • Constructor Summary

      Constructors 
      Constructor Description
      Webserver​(int port)
      Constructs a web server.
      Webserver​(java.lang.String port)
      Constructs a web server.
    • Method Summary

      All Methods Static Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      void addTranslator​(ClassPool cp, Translator t)
      Adds a translator, which is called whenever a client requests a class file.
      void doReply​(java.io.InputStream in, java.io.OutputStream out, java.lang.String cmd)
      Proceses a HTTP request from a client.
      void end()
      Closes the socket.
      void logging​(java.lang.String msg)
      Prints a log message.
      void logging​(java.lang.String msg1, java.lang.String msg2)
      Prints a log message.
      void logging​(java.lang.String msg1, java.lang.String msg2, java.lang.String msg3)
      Prints a log message.
      void logging2​(java.lang.String msg)
      Prints a log message with indentation.
      static void main​(java.lang.String[] args)
      Starts a web server.
      void run()
      Begins the HTTP service.
      void setClassPool​(ClassPool loader)
      Requests the web server to use the specified ClassPool object for obtaining a class file.
      • Methods inherited from class java.lang.Object

        equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
    • Field Detail

      • debugDir

        public java.lang.String debugDir
        If this field is not null, the class files taken from ClassPool are written out under the directory specified by this field. The directory name must not end with a directory separator.
      • htmlfileBase

        public java.lang.String htmlfileBase
        The top directory of html (and .gif, .class, ...) files. It must end with the directory separator such as "/". (For portability, "/" should be used as the directory separator. Javassist automatically translates "/" into a platform-dependent character.) If this field is null, the top directory is the current one where the JVM is running.

        If the given URL indicates a class file and the class file is not found under the directory specified by this variable, then Class.getResourceAsStream() is called for searching the Java class paths.

    • Constructor Detail

      • Webserver

        public Webserver​(java.lang.String port)
                  throws java.io.IOException
        Constructs a web server.
        Parameters:
        port - port number
        Throws:
        java.io.IOException
      • Webserver

        public Webserver​(int port)
                  throws java.io.IOException
        Constructs a web server.
        Parameters:
        port - port number
        Throws:
        java.io.IOException
    • Method Detail

      • main

        public static void main​(java.lang.String[] args)
                         throws java.io.IOException
        Starts a web server. The port number is specified by the first argument.
        Throws:
        java.io.IOException
      • setClassPool

        public void setClassPool​(ClassPool loader)
        Requests the web server to use the specified ClassPool object for obtaining a class file.
      • end

        public void end()
                 throws java.io.IOException
        Closes the socket.
        Throws:
        java.io.IOException
      • logging

        public void logging​(java.lang.String msg)
        Prints a log message.
      • logging

        public void logging​(java.lang.String msg1,
                            java.lang.String msg2)
        Prints a log message.
      • logging

        public void logging​(java.lang.String msg1,
                            java.lang.String msg2,
                            java.lang.String msg3)
        Prints a log message.
      • logging2

        public void logging2​(java.lang.String msg)
        Prints a log message with indentation.
      • run

        public void run()
        Begins the HTTP service.
      • doReply

        public void doReply​(java.io.InputStream in,
                            java.io.OutputStream out,
                            java.lang.String cmd)
                     throws java.io.IOException,
                            BadHttpRequest
        Proceses a HTTP request from a client.
        Parameters:
        out - the output stream to a client
        cmd - the command received from a client
        Throws:
        java.io.IOException
        BadHttpRequest