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/*
* Copyright (c) 2004-2010, Kohsuke Kawaguchi
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification, are permitted provided
* that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright notice, this list of
* conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright notice, this list of
* conditions and the following disclaimer in the documentation and/or other materials
* provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS
* OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
* OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
* IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
* THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
package org.kohsuke.stapler;
import javax.servlet.ServletException;
import java.io.IOException;
import java.lang.reflect.InvocationTargetException;
import java.util.logging.Level;
import java.util.logging.Logger;
/**
* Controls the dispatching of incoming HTTP requests.
*
* @author Kohsuke Kawaguchi
*/
public abstract class Dispatcher {
/**
* Trys to handle the given request and returns true
* if it succeeds. Otherwise false.
*
*
* We have a few known strategies for handling requests
* (for example, one is to try to treat the request as JSP invocation,
* another might be try getXXX(), etc) So we use a list of
* {@link Dispatcher} and try them one by one until someone
* returns true.
*/
public abstract boolean dispatch(RequestImpl req, ResponseImpl rsp, Object node)
throws IOException, ServletException, IllegalAccessException, InvocationTargetException;
/**
* Diagnostic string that explains this dispatch rule.
*/
public abstract String toString();
public static boolean traceable() {
return TRACE || TRACE_PER_REQUEST || LOGGER.isLoggable(Level.FINE);
}
public static void traceEval(StaplerRequest req, StaplerResponse rsp, Object node) {
trace(req,rsp,String.format("-> evaluate(%s%s,\"%s\")",
node==null?"null":'<'+node.toString()+'>',
node==null?"":" :"+node.getClass().getName(),
((RequestImpl)req).tokens.assembleOriginalRestOfPath()));
}
public static void traceEval(StaplerRequest req, StaplerResponse rsp, Object node, String prefix, String suffix) {
trace(req,rsp,String.format("-> evaluate(%s<%s>%s,\"%s\")",
prefix,node,suffix,
((RequestImpl)req).tokens.assembleOriginalRestOfPath()));
}
public static void traceEval(StaplerRequest req, StaplerResponse rsp, Object node, String expression) {
trace(req,rsp,String.format("-> evaluate(<%s>.%s,\"%s\")",
node,expression,
((RequestImpl)req).tokens.assembleOriginalRestOfPath()));
}
public static void trace(StaplerRequest req, StaplerResponse rsp, String msg, Object... args) {
trace(req,rsp,String.format(msg,args));
}
public static void trace(StaplerRequest req, StaplerResponse rsp, String msg) {
if(isTraceEnabled(req))
EvaluationTrace.get(req).trace(rsp,msg);
if(LOGGER.isLoggable(Level.FINE))
LOGGER.fine(msg);
}
/**
* Checks if tracing is enabled for the given request. Tracing can be
* enabled globally with the "stapler.trace=true" system property. Tracing
* can be enabled per-request by setting "stapler.trace.per-request=true"
* and sending an "X-Stapler-Trace" header set to "true" with the request.
*/
public static boolean isTraceEnabled(StaplerRequest req) {
if (TRACE)
return true;
if (TRACE_PER_REQUEST && "true".equals(req.getHeader("X-Stapler-Trace")))
return true;
return false;
}
/**
* This flag will activate the evaluation trace.
* It adds the evaluation process as HTTP headers,
* and when the evaluation failed, special diagnostic 404 page will be rendered.
* Useful for developer assistance.
*/
public static boolean TRACE = Boolean.getBoolean("stapler.trace");
/**
* This flag will activate the per-request evaluation trace for requests
* that have X-Stapler-Trace set to "true".
* It adds the evaluation process as HTTP headers,
* and when the evaluation failed, special diagnostic 404 page will be rendered.
* Useful for developer assistance.
*/
public static boolean TRACE_PER_REQUEST = Boolean.getBoolean("stapler.trace.per-request");
private static final Logger LOGGER = Logger.getLogger(Dispatcher.class.getName());
}