org.jolokia.http

Class AgentServlet

java.lang.Object

javax.servlet.GenericServlet

javax.servlet.http.HttpServlet

org.jolokia.http.AgentServlet

All Implemented Interfaces:

Serializable, javax.servlet.Servlet, javax.servlet.ServletConfig

public class AgentServlet
extends javax.servlet.http.HttpServlet

Agent servlet which connects to a local JMX MBeanServer for JMX operations.

It uses a REST based approach which translates a GET Url into a request. See the reference documentation for a detailed description of this servlet's features.

Since:

Apr 18, 2009

Author:

roland@jolokia.org

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
AgentServlet() No argument constructor, used e.g. by an servlet descriptor when creating the servlet out of web.xml
AgentServlet(Restrictor pRestrictor) Constructor taking a restrictor to use

Method Summary

Methods

Modifier and Type	Method and Description
protected LogHandler	createLogHandler(javax.servlet.ServletConfig pServletConfig, boolean pDebug) Create a log handler using this servlet's logging facility for logging.
protected Restrictor	createRestrictor(String pLocation) Create a restrictor restrictor to use.
void	destroy()
protected void	doGet(javax.servlet.http.HttpServletRequest req, javax.servlet.http.HttpServletResponse resp)
protected void	doOptions(javax.servlet.http.HttpServletRequest req, javax.servlet.http.HttpServletResponse resp) OPTION requests are treated as CORS preflight requests
protected void	doPost(javax.servlet.http.HttpServletRequest req, javax.servlet.http.HttpServletResponse resp)
protected LogHandler	getLogHandler() Get the installed log handler
void	init(javax.servlet.ServletConfig pServletConfig) Initialize the backend systems, the log handler and the restrictor.

Methods inherited from class javax.servlet.http.HttpServlet

doDelete, doHead, doPut, doTrace, getLastModified, service, service

Methods inherited from class javax.servlet.GenericServlet

getInitParameter, getInitParameterNames, getServletConfig, getServletContext, getServletInfo, getServletName, init, log, log

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

AgentServlet

public AgentServlet()

No argument constructor, used e.g. by an servlet descriptor when creating the servlet out of web.xml

AgentServlet

public AgentServlet(Restrictor pRestrictor)

Constructor taking a restrictor to use

Parameters:

pRestrictor - restrictor to use or null if the restrictor should be created in the default way (createRestrictor(String))

Method Detail

getLogHandler

protected LogHandler getLogHandler()

Get the installed log handler

Returns:

loghandler used for logging.

createRestrictor

protected Restrictor createRestrictor(String pLocation)

Create a restrictor restrictor to use. By default, a policy file is looked up (with the URL given by the init parameter ConfigKey.POLICY_LOCATION or "/jolokia-access.xml" by default) and if not found an AllowAllRestrictor is used by default. This method is called during the init(ServletConfig) when initializing the subsystems and can be overridden for custom restrictor creation.

Parameters:

pLocation - location to lookup the restrictor

Returns:

the restrictor to use.

init

public void init(javax.servlet.ServletConfig pServletConfig)
          throws javax.servlet.ServletException

Initialize the backend systems, the log handler and the restrictor. A subclass can tune this step by overriding createRestrictor(String) and createLogHandler(ServletConfig, boolean)

Specified by:

init in interface javax.servlet.Servlet

Overrides:

init in class javax.servlet.GenericServlet

Parameters:

pServletConfig - servlet configuration

Throws:

javax.servlet.ServletException

createLogHandler

protected LogHandler createLogHandler(javax.servlet.ServletConfig pServletConfig,
                          boolean pDebug)

Create a log handler using this servlet's logging facility for logging. This method can be overridden to provide a custom log handler. This method is called before createRestrictor(String) so the log handler can already be used when building up the restrictor.

Parameters:

pServletConfig - servlet config from where to get information to build up the log handler

pDebug - whether to print out debug information.

Returns:

a default log handler

destroy

public void destroy()

Specified by:

destroy in interface javax.servlet.Servlet

Overrides:

destroy in class javax.servlet.GenericServlet

doGet

protected void doGet(javax.servlet.http.HttpServletRequest req,
         javax.servlet.http.HttpServletResponse resp)
              throws javax.servlet.ServletException,
                     IOException

Overrides:

doGet in class javax.servlet.http.HttpServlet

Throws:

javax.servlet.ServletException

IOException

doPost

protected void doPost(javax.servlet.http.HttpServletRequest req,
          javax.servlet.http.HttpServletResponse resp)
               throws javax.servlet.ServletException,
                      IOException

Overrides:

doPost in class javax.servlet.http.HttpServlet

Throws:

javax.servlet.ServletException

IOException

doOptions

protected void doOptions(javax.servlet.http.HttpServletRequest req,
             javax.servlet.http.HttpServletResponse resp)
                  throws javax.servlet.ServletException,
                         IOException

OPTION requests are treated as CORS preflight requests

Overrides:

doOptions in class javax.servlet.http.HttpServlet

Parameters:

req - the original request

resp - the response the answer are written to

Throws:

javax.servlet.ServletException

IOException