org.apache.catalina.util.ProcessEnvironment Maven / Gradle / Ivy
/*
* Copyright 1999,2004 The Apache Software Foundation.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.catalina.util;
import java.io.File;
import java.util.Enumeration;
import java.util.Hashtable;
import javax.servlet.ServletContext;
import javax.servlet.http.HttpServletRequest;
/**
* Encapsulates the Process environment and rules to derive
* that environment from the servlet container and request information.
* @author Martin Dengler [[email protected]]
* @version $Revision: 1.5 $, $Date: 2004/09/16 23:19:54 $
* @since Tomcat 4.0
*/
public class ProcessEnvironment {
private static org.apache.commons.logging.Log log=
org.apache.commons.logging.LogFactory.getLog( ProcessEnvironment.class );
/** context of the enclosing servlet */
private ServletContext context = null;
/** real file system directory of the enclosing servlet's web app */
private String webAppRootDir = null;
/** context path of enclosing servlet */
private String contextPath = null;
/** pathInfo for the current request */
protected String pathInfo = null;
/** servlet URI of the enclosing servlet */
private String servletPath = null;
/** derived process environment */
protected Hashtable env = null;
/** command to be invoked */
protected String command = null;
/** whether or not this object is valid or not */
protected boolean valid = false;
/** the debugging detail level for this instance. */
protected int debug = 0;
/** process' desired working directory */
protected File workingDirectory = null;
/**
* Creates a ProcessEnvironment and derives the necessary environment,
* working directory, command, etc.
* @param req HttpServletRequest for information provided by
* the Servlet API
* @param context ServletContext for information provided by
* the Servlet API
*/
public ProcessEnvironment(HttpServletRequest req,
ServletContext context) {
this(req, context, 0);
}
/**
* Creates a ProcessEnvironment and derives the necessary environment,
* working directory, command, etc.
* @param req HttpServletRequest for information provided by
* the Servlet API
* @param context ServletContext for information provided by
* the Servlet API
* @param debug int debug level (0 == none, 4 == medium, 6 == lots)
*/
public ProcessEnvironment(HttpServletRequest req,
ServletContext context, int debug) {
this.debug = debug;
setupFromContext(context);
setupFromRequest(req);
this.valid = deriveProcessEnvironment(req);
if (log.isDebugEnabled())
log.debug(this.getClass().getName() + "() ctor, debug level " +
debug);
}
/**
* Uses the ServletContext to set some process variables
* @param context ServletContext for information provided by
* the Servlet API
*/
protected void setupFromContext(ServletContext context) {
this.context = context;
this.webAppRootDir = context.getRealPath("/");
}
/**
* Uses the HttpServletRequest to set most process variables
* @param req HttpServletRequest for information provided by
* the Servlet API
*/
protected void setupFromRequest(HttpServletRequest req) {
this.contextPath = req.getContextPath();
this.pathInfo = req.getPathInfo();
this.servletPath = req.getServletPath();
}
/**
* Print important process environment information in an
* easy-to-read HTML table
* @return HTML string containing process environment info
*/
public String toString() {
StringBuffer sb = new StringBuffer();
sb.append("");
sb.append("");
sb.append("ProcessEnvironment Info Debug Level ");
sb.append(debug);
sb.append(" Validity: ");
sb.append(isValid());
sb.append(" ");
sb.append(s);
sb.append(" ");
sb.append(blanksToString((String)env.get(s),
"[will be set to blank]"));
sb.append("
Derived Command ");
sb.append(nullsToBlanks(command));
sb.append(" Working Directory ");
if (workingDirectory != null) {
sb.append(workingDirectory.toString());
}
sb.append("
end.");
return sb.toString();
}
/**
* Gets derived command string
* @return command string
*/
public String getCommand() {
return command;
}
/**
* Sets the desired command string
* @param command String command as desired
* @return command string
*/
protected String setCommand(String command) {
return command;
}
/**
* Gets this process' derived working directory
* @return working directory
*/
public File getWorkingDirectory() {
return workingDirectory;
}
/**
* Gets process' environment
* @return process' environment
*/
public Hashtable getEnvironment() {
return env;
}
/**
* Sets process' environment
* @param env process' environment
* @return Hashtable to which the process' environment was set
*/
public Hashtable setEnvironment(Hashtable env) {
this.env = env;
return this.env;
}
/**
* Gets validity status
* @return true if this environment is valid, false otherwise
*/
public boolean isValid() {
return valid;
}
/**
* Converts null strings to blank strings ("")
* @param s string to be converted if necessary
* @return a non-null string, either the original or the empty string
* ("") if the original was null
*/
protected String nullsToBlanks(String s) {
return nullsToString(s, "");
}
/**
* Converts null strings to another string
* @param couldBeNull string to be converted if necessary
* @param subForNulls string to return instead of a null string
* @return a non-null string, either the original or the substitute
* string if the original was null
*/
protected String nullsToString(String couldBeNull, String subForNulls) {
return (couldBeNull == null ? subForNulls : couldBeNull);
}
/**
* Converts blank strings to another string
* @param couldBeBlank string to be converted if necessary
* @param subForBlanks string to return instead of a blank string
* @return a non-null string, either the original or the substitute
* string if the original was null or empty ("")
*/
protected String blanksToString(String couldBeBlank,
String subForBlanks) {
return (("".equals(couldBeBlank) || couldBeBlank == null) ?
subForBlanks : couldBeBlank);
}
/**
* Constructs the Process environment to be supplied to the invoked
* process. Defines an environment no environment variables.
*
* Should be overriden by subclasses to perform useful setup.
*
*
* @param req request associated with the
* Process' invocation
* @return true if environment was set OK, false if there was a problem
* and no environment was set
*/
protected boolean deriveProcessEnvironment(HttpServletRequest req) {
Hashtable envp = new Hashtable();
command = getCommand();
if (command != null) {
workingDirectory = new
File(command.substring(0,
command.lastIndexOf(File.separator)));
envp.put("X_TOMCAT_COMMAND_PATH", command); //for kicks
}
this.env = envp;
return true;
}
/**
* Gets the root directory of the web application to which this process\
* belongs
* @return root directory
*/
public String getWebAppRootDir() {
return webAppRootDir;
}
public String getContextPath(){
return contextPath;
}
public ServletContext getContext(){
return context;
}
public String getServletPath(){
return servletPath;
}
}