/**
* 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.jooby.metrics;
import java.io.ByteArrayOutputStream;
import java.lang.management.ManagementFactory;
import org.jooby.MediaType;
import org.jooby.Request;
import org.jooby.Response;
import org.jooby.Route.Handler;
import org.jooby.Status;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.codahale.metrics.jvm.ThreadDump;
/**
* Prints thread states (a.k.a thread dump).
*
* @author edgar
* @since 0.13.0
*/
public class ThreadDumpHandler implements Handler {
/** The logging system. */
private final Logger log = LoggerFactory.getLogger(getClass());
private ThreadDump threadDump;
{
try {
// Some PaaS like Google App Engine blacklist java.lang.managament
this.threadDump = new ThreadDump(ManagementFactory.getThreadMXBean());
} catch (Exception ex) {
log.warn("Thread dump isn't available", ex);
}
}
@Override
public void handle(final Request req, final Response rsp) throws Throwable {
Object data;
Status status;
if (threadDump == null) {
data = "Sorry your runtime environment does not allow to dump threads.";
status = Status.NOT_IMPLEMENTED;
} else {
final ByteArrayOutputStream output = new ByteArrayOutputStream();
threadDump.dump(output);
data = output.toByteArray();
status = Status.OK;
}
rsp.type(MediaType.plain)
.status(status)
.header("Cache-Control", "must-revalidate,no-cache,no-store")
.send(data);
}
}