StandardWrapperValve.java
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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.core;
import java.io.IOException;
import java.util.concurrent.atomic.AtomicInteger;
import java.util.concurrent.atomic.AtomicLong;
import javax.servlet.DispatcherType;
import javax.servlet.RequestDispatcher;
import javax.servlet.Servlet;
import javax.servlet.ServletException;
import javax.servlet.UnavailableException;
import javax.servlet.http.HttpServletResponse;
import org.apache.catalina.Container;
import org.apache.catalina.Context;
import org.apache.catalina.Globals;
import org.apache.catalina.LifecycleException;
import org.apache.catalina.connector.Request;
import org.apache.catalina.connector.Response;
import org.apache.catalina.valves.ValveBase;
import org.apache.coyote.BadRequestException;
import org.apache.coyote.CloseNowException;
import org.apache.tomcat.util.ExceptionUtils;
import org.apache.tomcat.util.buf.MessageBytes;
import org.apache.tomcat.util.log.SystemLogHandler;
import org.apache.tomcat.util.res.StringManager;
/**
* Valve that implements the default basic behavior for the <code>StandardWrapper</code> container implementation.
*
* @author Craig R. McClanahan
*/
final class StandardWrapperValve extends ValveBase {
private static final StringManager sm = StringManager.getManager(StandardWrapperValve.class);
// ------------------------------------------------------ Constructor
StandardWrapperValve() {
super(true);
}
// ----------------------------------------------------- Instance Variables
// Some JMX statistics. This valve is associated with a StandardWrapper.
// We expose the StandardWrapper as JMX ( j2eeType=Servlet ). The fields
// are here for performance.
private final AtomicLong processingTime = new AtomicLong();
private volatile long maxTime;
private volatile long minTime = Long.MAX_VALUE;
private final AtomicInteger requestCount = new AtomicInteger(0);
private final AtomicInteger errorCount = new AtomicInteger(0);
// --------------------------------------------------------- Public Methods
/**
* Invoke the servlet we are managing, respecting the rules regarding servlet lifecycle and SingleThreadModel
* support.
*
* @param request Request to be processed
* @param response Response to be produced
*
* @exception IOException if an input/output error occurred
* @exception ServletException if a servlet error occurred
*/
@Override
public void invoke(Request request, Response response) throws IOException, ServletException {
// Initialize local variables we may need
boolean unavailable = false;
Throwable throwable = null;
// This should be a Request attribute...
long t1 = System.currentTimeMillis();
requestCount.incrementAndGet();
StandardWrapper wrapper = (StandardWrapper) getContainer();
Servlet servlet = null;
Context context = (Context) wrapper.getParent();
// Check for the application being marked unavailable
if (!context.getState().isAvailable()) {
response.sendError(HttpServletResponse.SC_SERVICE_UNAVAILABLE,
sm.getString("standardContext.isUnavailable"));
unavailable = true;
}
// Check for the servlet being marked unavailable
if (!unavailable && wrapper.isUnavailable()) {
container.getLogger().info(sm.getString("standardWrapper.isUnavailable", wrapper.getName()));
checkWrapperAvailable(response, wrapper);
unavailable = true;
}
// Allocate a servlet instance to process this request
try {
if (!unavailable) {
servlet = wrapper.allocate();
}
} catch (UnavailableException e) {
container.getLogger().error(sm.getString("standardWrapper.allocateException", wrapper.getName()), e);
checkWrapperAvailable(response, wrapper);
} catch (ServletException e) {
container.getLogger().error(sm.getString("standardWrapper.allocateException", wrapper.getName()),
StandardWrapper.getRootCause(e));
throwable = e;
exception(request, response, e);
} catch (Throwable e) {
ExceptionUtils.handleThrowable(e);
container.getLogger().error(sm.getString("standardWrapper.allocateException", wrapper.getName()), e);
throwable = e;
exception(request, response, e);
servlet = null;
}
MessageBytes requestPathMB = request.getRequestPathMB();
DispatcherType dispatcherType = DispatcherType.REQUEST;
if (request.getDispatcherType() == DispatcherType.ASYNC) {
dispatcherType = DispatcherType.ASYNC;
}
request.setAttribute(Globals.DISPATCHER_TYPE_ATTR, dispatcherType);
request.setAttribute(Globals.DISPATCHER_REQUEST_PATH_ATTR, requestPathMB);
// Create the filter chain for this request
ApplicationFilterChain filterChain = ApplicationFilterFactory.createFilterChain(request, wrapper, servlet);
// Call the filter chain for this request
// NOTE: This also calls the servlet's service() method
Container container = this.container;
try {
if ((servlet != null) && (filterChain != null)) {
// Swallow output if needed
if (context.getSwallowOutput()) {
try {
SystemLogHandler.startCapture();
if (request.isAsyncDispatching()) {
request.getAsyncContextInternal().doInternalDispatch();
} else {
filterChain.doFilter(request.getRequest(), response.getResponse());
}
} finally {
String log = SystemLogHandler.stopCapture();
if (log != null && log.length() > 0) {
context.getLogger().info(log);
}
}
} else {
if (request.isAsyncDispatching()) {
request.getAsyncContextInternal().doInternalDispatch();
} else {
filterChain.doFilter(request.getRequest(), response.getResponse());
}
}
}
} catch (BadRequestException e) {
if (container.getLogger().isDebugEnabled()) {
container.getLogger().debug(
sm.getString("standardWrapper.serviceException", wrapper.getName(), context.getName()), e);
}
throwable = e;
exception(request, response, e, HttpServletResponse.SC_BAD_REQUEST);
} catch (CloseNowException e) {
if (container.getLogger().isDebugEnabled()) {
container.getLogger().debug(
sm.getString("standardWrapper.serviceException", wrapper.getName(), context.getName()), e);
}
throwable = e;
exception(request, response, e);
} catch (IOException e) {
container.getLogger()
.error(sm.getString("standardWrapper.serviceException", wrapper.getName(), context.getName()), e);
throwable = e;
exception(request, response, e);
} catch (UnavailableException e) {
container.getLogger()
.error(sm.getString("standardWrapper.serviceException", wrapper.getName(), context.getName()), e);
wrapper.unavailable(e);
checkWrapperAvailable(response, wrapper);
// Do not save exception in 'throwable', because we
// do not want to do exception(request, response, e) processing
} catch (ServletException e) {
Throwable rootCause = StandardWrapper.getRootCause(e);
if (!(rootCause instanceof BadRequestException)) {
container.getLogger().error(sm.getString("standardWrapper.serviceExceptionRoot", wrapper.getName(),
context.getName(), e.getMessage()), rootCause);
}
throwable = e;
exception(request, response, e);
} catch (Throwable e) {
ExceptionUtils.handleThrowable(e);
container.getLogger()
.error(sm.getString("standardWrapper.serviceException", wrapper.getName(), context.getName()), e);
throwable = e;
exception(request, response, e);
} finally {
// Release the filter chain (if any) for this request
if (filterChain != null) {
filterChain.release();
}
// Deallocate the allocated servlet instance
try {
if (servlet != null) {
wrapper.deallocate(servlet);
}
} catch (Throwable e) {
ExceptionUtils.handleThrowable(e);
container.getLogger().error(sm.getString("standardWrapper.deallocateException", wrapper.getName()), e);
if (throwable == null) {
throwable = e;
exception(request, response, e);
}
}
// If this servlet has been marked permanently unavailable,
// unload it and release this instance
try {
if ((servlet != null) && (wrapper.getAvailable() == Long.MAX_VALUE)) {
wrapper.unload();
}
} catch (Throwable e) {
ExceptionUtils.handleThrowable(e);
container.getLogger().error(sm.getString("standardWrapper.unloadException", wrapper.getName()), e);
if (throwable == null) {
exception(request, response, e);
}
}
long t2 = System.currentTimeMillis();
long time = t2 - t1;
processingTime.getAndAdd(time);
if (time > maxTime) {
maxTime = time;
}
if (time < minTime) {
minTime = time;
}
}
}
private void checkWrapperAvailable(Response response, StandardWrapper wrapper) throws IOException {
long available = wrapper.getAvailable();
if ((available > 0L) && (available < Long.MAX_VALUE)) {
response.setDateHeader("Retry-After", available);
response.sendError(HttpServletResponse.SC_SERVICE_UNAVAILABLE,
sm.getString("standardWrapper.isUnavailable", wrapper.getName()));
} else if (available == Long.MAX_VALUE) {
response.sendError(HttpServletResponse.SC_NOT_FOUND,
sm.getString("standardWrapper.notFound", wrapper.getName()));
}
}
// -------------------------------------------------------- Private Methods
/**
* Handle the specified ServletException encountered while processing the specified Request to produce the specified
* Response. Any exceptions that occur during generation of the exception report are logged and swallowed.
*
* @param request The request being processed
* @param response The response being generated
* @param exception The exception that occurred (which possibly wraps a root cause exception
*/
private void exception(Request request, Response response, Throwable exception) {
exception(request, response, exception, HttpServletResponse.SC_INTERNAL_SERVER_ERROR);
}
private void exception(Request request, Response response, Throwable exception, int errorCode) {
request.setAttribute(RequestDispatcher.ERROR_EXCEPTION, exception);
response.setStatus(errorCode);
response.setError();
}
public long getProcessingTime() {
return processingTime.get();
}
public long getMaxTime() {
return maxTime;
}
public long getMinTime() {
return minTime;
}
public int getRequestCount() {
return requestCount.get();
}
public int getErrorCount() {
return errorCount.get();
}
public void incrementErrorCount() {
errorCount.incrementAndGet();
}
@Override
protected void initInternal() throws LifecycleException {
// NOOP - Don't register this Valve in JMX
}
}