org.apache.catalina.util

Class ProcessHelper


public class ProcessHelper
extends java.lang.Object

Encapsulates the knowledge of how to run a CGI script, given the script's desired environment and (optionally) input/output streams

Exposes a run method used to actually invoke the CGI.

The CGI environment and settings are derived from the information passed to the constuctor.

The input and output streams can be set by the setInput and setResponse methods, respectively.

Version:
$Revision: 1.5 $, $Date: 2004/05/26 16:26:05 $

Author:
Martin Dengler [root@martindengler.com]

Constructor Summary

ProcessHelper(String command, Hashtable env, File wd, Hashtable params)
Creates a ProcessHelper and initializes its environment, working directory, and query parameters.

Method Summary

int
getIClientInputTimeout()
protected String
getPostInput(Hashtable params)
Gets a string for input to a POST cgi script
boolean
isReady()
Gets ready status
void
run()
Executes a process script with the desired environment, current working directory, and input/output streams

This implements the following CGI specification recommedations:

  • Servers SHOULD provide the "query" component of the script-URI as command-line arguments to scripts if it does not contain any unencoded "=" characters and the command-line arguments can be generated in an unambiguous manner.
void
setIClientInputTimeout(int iClientInputTimeout)
void
setInput(InputStream stdin)
Sets standard input to be passed on to the invoked cgi script
void
setResponse(HttpServletResponse response)
Sets HttpServletResponse object used to set headers and send output to
protected void
updateReadyStatus()
Checks & sets ready status

Constructor Details

ProcessHelper

public ProcessHelper(String command,
                     Hashtable env,
                     File wd,
                     Hashtable params)
Creates a ProcessHelper and initializes its environment, working directory, and query parameters.
Input/output streams (optional) are set using the setInput and setResponse methods, respectively.

Parameters:
command - string full path to command to be executed
env - Hashtable with the desired script environment
wd - File with the script's desired working directory
params - Hashtable with the script's query parameters

Method Details

getIClientInputTimeout

public int getIClientInputTimeout()


getPostInput

protected String getPostInput(Hashtable params)
Gets a string for input to a POST cgi script

Parameters:
params - Hashtable of query parameters to be passed to the CGI script

Returns:
for use as input to the CGI script


isReady

public boolean isReady()
Gets ready status

Returns:
false if not ready (run will throw an exception), true if ready


run

public void run()
            throws IOException
Executes a process script with the desired environment, current working directory, and input/output streams

This implements the following CGI specification recommedations:

  • Servers SHOULD provide the "query" component of the script-URI as command-line arguments to scripts if it does not contain any unencoded "=" characters and the command-line arguments can be generated in an unambiguous manner.
  • Servers SHOULD set the AUTH_TYPE metavariable to the value of the "auth-scheme" token of the "Authorization" if it was supplied as part of the request header. See getCGIEnvironment method.
  • Where applicable, servers SHOULD set the current working directory to the directory in which the script is located before invoking it.
  • Server implementations SHOULD define their behavior for the following cases:
  • Allowed characters in pathInfo: This implementation does not allow ASCII NUL nor any character which cannot be URL-encoded according to internet standards;
  • Allowed characters in path segments: This implementation does not allow non-terminal NULL segments in the the path -- IOExceptions may be thrown;
  • "." and ".." path segments: This implementation does not allow "." and ".." in the the path, and such characters will result in an IOException being thrown;
  • Implementation limitations: This implementation does not impose any limitations except as documented above. This implementation may be limited by the servlet container used to house this implementation. In particular, all the primary CGI variable values are derived either directly or indirectly from the container's implementation of the Servlet API methods.
For more information, see java.lang.Runtime#exec(String command, String[] envp, File dir)


setIClientInputTimeout

public void setIClientInputTimeout(int iClientInputTimeout)


setInput

public void setInput(InputStream stdin)
Sets standard input to be passed on to the invoked cgi script

Parameters:
stdin - InputStream to be used


setResponse

public void setResponse(HttpServletResponse response)
Sets HttpServletResponse object used to set headers and send output to

Parameters:
response - HttpServletResponse to be used


updateReadyStatus

protected void updateReadyStatus()
Checks & sets ready status


Copyright B) 2000-2003 Apache Software Foundation. All Rights Reserved.