OpenNMS API 1.2.3

org.opennms.web.graph
Class RRDGraphServlet

java.lang.Object
  extended byjavax.servlet.GenericServlet
      extended byjavax.servlet.http.HttpServlet
          extended byorg.opennms.web.graph.RRDGraphServlet
All Implemented Interfaces:
java.io.Serializable, javax.servlet.Servlet, javax.servlet.ServletConfig

public class RRDGraphServlet
extends javax.servlet.http.HttpServlet

A servlet that creates a graph of network performance data using the RRDTool .

This servlet executes an rrdtool graph command in another process, piping its PNG file to standard out. The servlet then reads that PNG file and returns it on the ServletOutputStream.

This servlet requires the following parameters:

Author:
Lawrence Karnowski , OpenNMS
See Also:
Serialized Form

Field Summary
protected  java.lang.String commandPrefix
          The prefix for the RRDtool command (including the executable's pathname) as specified in the rrdtool-graph properties file.
protected  java.lang.String mimeType
          The mime type of the image we will return.
protected  java.util.Map reportMap
          Holds the graph definitions specified in the rrdtool-graph properties file.
protected  java.io.File workDir
          The working directory as specifed in the rrdtool-graph properties file.
 
Fields inherited from class javax.servlet.http.HttpServlet
 
Fields inherited from class javax.servlet.GenericServlet
 
Constructor Summary
RRDGraphServlet()
           
 
Method Summary
protected  java.lang.String createPrefabCommand(javax.servlet.http.HttpServletRequest request, java.lang.String reportName, java.lang.String[] rrds, java.lang.String propertiesFile, java.lang.String start, java.lang.String end)
           
 void doGet(javax.servlet.http.HttpServletRequest request, javax.servlet.http.HttpServletResponse response)
          Checks the parameters passed to this servlet, and if all are okay, executes the RRDTool command in another process and pipes its PNG output to the ServletOutputStream back to the requesting web browser.
 void init()
          Initializes this servlet by reading the rrdtool-graph properties file.
 
Methods inherited from class javax.servlet.http.HttpServlet
doDelete, doHead, doOptions, doPost, doPut, doTrace, getLastModified, service, service
 
Methods inherited from class javax.servlet.GenericServlet
destroy, 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
 

Field Detail

workDir

protected java.io.File workDir
The working directory as specifed in the rrdtool-graph properties file.


commandPrefix

protected java.lang.String commandPrefix
The prefix for the RRDtool command (including the executable's pathname) as specified in the rrdtool-graph properties file.


mimeType

protected java.lang.String mimeType
The mime type of the image we will return.


reportMap

protected java.util.Map reportMap
Holds the graph definitions specified in the rrdtool-graph properties file. It maps report names to PrefabGraphinstances.

Constructor Detail

RRDGraphServlet

public RRDGraphServlet()
Method Detail

init

public void init()
          throws javax.servlet.ServletException
Initializes this servlet by reading the rrdtool-graph properties file.

Throws:
javax.servlet.ServletException

doGet

public void doGet(javax.servlet.http.HttpServletRequest request,
                  javax.servlet.http.HttpServletResponse response)
           throws javax.servlet.ServletException,
                  java.io.IOException
Checks the parameters passed to this servlet, and if all are okay, executes the RRDTool command in another process and pipes its PNG output to the ServletOutputStream back to the requesting web browser.

Throws:
javax.servlet.ServletException
java.io.IOException

createPrefabCommand

protected java.lang.String createPrefabCommand(javax.servlet.http.HttpServletRequest request,
                                               java.lang.String reportName,
                                               java.lang.String[] rrds,
                                               java.lang.String propertiesFile,
                                               java.lang.String start,
                                               java.lang.String end)
                                        throws javax.servlet.ServletException
Throws:
javax.servlet.ServletException

OpenNMS API 1.2.3

Generated by eevans on May 29 2005 2015.