com.yworks.yfiles.server.tiles.demos
Class InfoServlet

java.lang.Object
  javax.servlet.GenericServlet
      javax.servlet.http.HttpServlet
          com.yworks.yfiles.server.tiles.servlet.BaseServlet
              com.yworks.yfiles.server.tiles.demos.InfoServlet

All Implemented Interfaces:

Serializable, Servlet, ServletConfig

public class InfoServlet
extends BaseServlet

This servlet provides information on a graph.

The information is available on diferent levels. There is information on the graph as a whole, e.g., the number of nodes. There is information on parts of the graph, e.g., on a single node or a single edge. Information for a certain aspect of the graph can also point to further information. The information for an edge for example points to two node informations, one for the source node and one for the target node of the edge.

The information is accessed using a path in a logical tree. The information for graph foo is accessible via a URL like the following.

   http://www.mycompany.com/yfiles-ajax/graphs/foo
 

Information on node 42 of that graph is accessed like this.

   http://www.mycompany.com/yfiles-ajax/graphs/foo/nodes/42
 

The returned information is in JSON format.

See Also:

Serialized Form

Constructor Summary

InfoServlet()

Method Summary

protected String[]	getRequestPath(HttpServletRequest request) returns the request path as an array of Strings, one for each element of the path.
protected void	handleGetRequest(HttpServletRequest request, HttpServletResponse response) answers "GET" requests for graph information.
protected void	handlePostRequest(HttpServletRequest request, HttpServletResponse response) calls handleGetRequest(HttpServletRequest, HttpServletResponse).

Methods inherited from class com.yworks.yfiles.server.tiles.servlet.BaseServlet

cachedGraphs, cacheGraph, doGet, doPost, getEdgeDescription, getEdgeURL, getForId, getGraph, getGraphBounds, getId, getId, getId, getId, getNodeDescription, getNodeURL, getWriter, hasDescriptions, hasURLs, init, initialize, newGraph, setEdgeDescription, setEdgeURL, setNodeDescription, setNodeURL, uncacheGraph, writeWorldBounds

Methods inherited from class javax.servlet.http.HttpServlet

doDelete, doHead, doOptions, 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

Constructor Detail

InfoServlet

public InfoServlet()

Method Detail

handleGetRequest

protected void handleGetRequest(HttpServletRequest request,
                                HttpServletResponse response)
                         throws ServletException,
                                IOException

answers "GET" requests for graph information.

A request has the format of a logical path starting with "/graphs", e.g., information on node 42 of graph foo is accessed like this.

   http://www.mycompany.com/yfiles-ajax/graphs/foo/nodes/42
 

The following logical paths are supported.

1. .../graphs returns a list of known graph names (we assume that foo is among them in the following)
2. .../graphs/foo returns global information on the graph named foo
3. .../graphs/foo/world_bounds returns the world bounds for the graph named foo
4. .../graphs/foo/nodes returns the list of nodes for the graph named foo
5. .../graphs/foo/edges returns the list of edges for the graph named foo
6. .../graphs/foo/nodes/42 returns information on node 42 of the graph named foo
7. .../graphs/foo/edges/7 returns information on edge 7 of the graph named foo

A graph is known to this servlet for the current session, if it is cached in the session (see BaseServlet.cachedGraphs(HttpSession)).

NOTE: Information on a graph can only be obtained, if it is already in the cache for the session.

Overrides:

handleGetRequest in class BaseServlet

Parameters:

request - the request

response - the response to write to

Throws:

ServletException

IOException

handlePostRequest

protected void handlePostRequest(HttpServletRequest request,
                                 HttpServletResponse response)
                          throws ServletException,
                                 IOException

calls handleGetRequest(HttpServletRequest, HttpServletResponse). This is a convenience method, since it might be better to use a "POST" request, if the graph changes over time and the browser caches "GET" requests. "POST" requests are never cached.

Overrides:

handlePostRequest in class BaseServlet

Parameters:

request - the request

response - the response to write to

Throws:

ServletException

IOException

getRequestPath

protected String[] getRequestPath(HttpServletRequest request)

returns the request path as an array of Strings, one for each element of the path. This method also normalizes the path by removing a trailing slash and everything before "/graphs".

Parameters:

request - the request

Returns:

the elements of the request path as an array of strings