Develop Reference

How to resolve "org.eclipse.jetty.websocket.api.MessageTooLargeException" for Java WebSocketStompClient

When I'm running a Java WebSocketStompClient, I got below error:
org.eclipse.jetty.websocket.api.MessageTooLargeException: Text message size [73728] exceeds maximum size [65536]
Sample code:
import org.apache.log4j.Logger;
import org.springframework.messaging.simp.stomp.StompFrameHandler;
import org.springframework.messaging.simp.stomp.StompHeaders;
import org.springframework.messaging.simp.stomp.StompSession;
import org.springframework.messaging.simp.stomp.StompSessionHandlerAdapter;
import org.springframework.util.concurrent.ListenableFuture;
import org.springframework.web.socket.WebSocketHttpHeaders;
import org.springframework.web.socket.client.WebSocketClient;
import org.springframework.web.socket.client.standard.StandardWebSocketClient;
import org.springframework.web.socket.messaging.WebSocketStompClient;
import org.springframework.web.socket.sockjs.client.SockJsClient;
import org.springframework.web.socket.sockjs.client.Transport;
import org.springframework.web.socket.sockjs.client.WebSocketTransport;
import org.springframework.web.socket.sockjs.frame.Jackson2SockJsMessageCodec;
import java.lang.reflect.Type;
import java.util.Collections;
import java.util.List;
import java.util.concurrent.ExecutionException;
public class HelloClient {
private static Logger logger = Logger.getLogger(HelloClient.class);
StompSession session;
private final static WebSocketHttpHeaders headers = new WebSocketHttpHeaders();
public ListenableFuture<StompSession> connect() {
Transport webSocketTransport = new WebSocketTransport(new StandardWebSocketClient());
List<Transport> transports = Collections.singletonList(webSocketTransport);
SockJsClient sockJsClient = new SockJsClient(transports);
sockJsClient.setMessageCodec(new Jackson2SockJsMessageCodec());
WebSocketStompClient stompClient = new WebSocketStompClient(sockJsClient);
long[] hb = stompClient.getDefaultHeartbeat();
boolean en = stompClient.isDefaultHeartbeatEnabled();
long timeout = stompClient.getReceiptTimeLimit();
String url = "https://www.test.com";
return stompClient.connect(url, headers, new MyHandler());
}
public void subscribeMsg(StompSession stompSession) throws ExecutionException, InterruptedException {
stompSession.subscribe("/topic/test", new StompFrameHandler() {
public Type getPayloadType(StompHeaders stompHeaders) {
return byte[].class;
}
public void handleFrame(StompHeaders stompHeaders, Object o) {
logger.info("Received message " + new String((byte[]) o));
String response = new String((byte[]) o);
}
});
}
private class MyHandler extends StompSessionHandlerAdapter {
public void afterConnected(StompSession stompSession, StompHeaders stompHeaders) {
logger.info("Now connected");
session = stompSession;
}
}
public boolean isConnected() {
try {
Thread.sleep(500);
return session != null && session.isConnected();
} catch (Exception e) {
logger.warn("Error happens when checking connection status, ", e);
return false;
}
}
public static void main(String[] args) throws Exception {
HelloClient helloClient = new HelloClient();
ListenableFuture<StompSession> f = helloClient.connect();
StompSession stompSession = f.get();
helloClient.subscribeMsg(stompSession);
while (true) {
if (!helloClient.isConnected()) {
logger.info("wss diconnected ");
logger.info("need re-create ");
}
}
}
}
How to increase the limitation for a Java stomp websocket client? I found some not related answers How can I set max buffer size for web socket client(Jetty) in Java which are not suitable for stomp websocket client.
Also tried stompClient.setInboundMessageSizeLimit(Integer.MAX_VALUE); which doesn't work.

How to create a simple JMX client?

Let say we have MBean on the server side with predefined API. I would like to call that MBean from client machine using API directly. How do I create simple JMX client to get remote java objects via RMI?

Usage
private CacheMBean<String, Message> messageStorage = newJmxClient(
CacheMBean.class,
"com.my.company:type=cache,name=MessageCacheImpl",
"service:jmx:rmi:///jndi/rmi://<host>:<port>/karaf-root",
"smx",
"smx");
...
Message message = messageStorage.get(messageId);
Implementation
import com.google.common.collect.ImmutableMap;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.io.IOException;
import java.lang.management.ManagementFactory;
import java.util.Map;
import javax.management.InstanceAlreadyExistsException;
import javax.management.JMX;
import javax.management.MBeanServer;
import javax.management.MBeanServerConnection;
import javax.management.MalformedObjectNameException;
import javax.management.ObjectInstance;
import javax.management.ObjectName;
import javax.management.StandardMBean;
import javax.management.remote.JMXConnector;
import javax.management.remote.JMXConnectorFactory;
import javax.management.remote.JMXServiceURL;
public final class JmxUtils {
private static final Logger LOG = LoggerFactory.getLogger(JmxUtils.class);
private JmxUtils() {
}
public static <T> T newJmxClient(Class<T> clazz, String objectName, String serviceUrl) {
return newJmxClient(clazz, objectName, serviceUrl, null, null);
}
public static <T> T newJmxClient(Class<T> clazz, String objectName, String serviceUrl, final String user, final String pass) {
try {
JMXServiceURL jmxServiceUrl = new JMXServiceURL(serviceUrl);
Map<String, ?> env = user == null ? null : ImmutableMap.of(JMXConnector.CREDENTIALS, new String[] {user, pass});
JMXConnector jmxc = JMXConnectorFactory.connect(jmxServiceUrl, env);
MBeanServerConnection mbsc = jmxc.getMBeanServerConnection();
ObjectName mbeanName = new ObjectName(objectName);
return JMX.newMBeanProxy(mbsc, mbeanName, clazz, true);
} catch (IOException | MalformedObjectNameException e) {
throw new RuntimeException("Can not create client for remote JMX " + serviceUrl, e);
}
}
/**
* #param objName
* domain:type=value[,name=value]
* #param implementation
* #param mbeanInterface
* #see ObjectName
* #see StandardMBean
*/
public static <I> ObjectInstance registerMBean(String objName, I implementation, Class<I> mbeanInterface) {
int counter = 0;
String uniqueSuffix = "";
MBeanServer mbs = ManagementFactory.getPlatformMBeanServer();
while (true) {
try {
ObjectName name = new ObjectName(objName + uniqueSuffix);
StandardMBean mbean = new StandardMBean(implementation, mbeanInterface);
return mbs.registerMBean(mbean, name);
} catch (InstanceAlreadyExistsException e) {
LOG.trace("JMX instance exists, trying next available", e);
uniqueSuffix = "" + ++counter;
} catch (Exception e) {
throw new RuntimeException(e);
}
}
}
/**
* #param objName
* #see ObjectName
*/
public static void unregisterMBean(String objName) {
try {
final MBeanServer mbs = ManagementFactory.getPlatformMBeanServer();
final ObjectName name = new ObjectName(objName);
mbs.unregisterMBean(name);
} catch (Exception e) {
throw new RuntimeException(e);
}
}
}

how to create large number of connects with netty 5.0

I want to create large number client connection to the server for the test purpose. I accomplish this by creating thread per connection, so I can only create 3000 connection on my machine. below is my code:
package com.stepnetwork.iot.apsclient.application;
import io.netty.bootstrap.Bootstrap;
import io.netty.buffer.ByteBuf;
import io.netty.buffer.Unpooled;
import io.netty.channel.*;
import io.netty.channel.socket.SocketChannel;
import io.netty.channel.socket.nio.NioSocketChannel;
/**
* Created by sam on 3/22/16.
*/
public class DtuClient extends Thread {
private static final String HOST = "192.168.54.36";
private static final int PORT = 30080;
private EventLoopGroup workerGroup;
private String dtuCode;
public DtuClient(String dtuCode, EventLoopGroup workerGroup) {
this.dtuCode = dtuCode;
this.workerGroup = workerGroup;
}
public void run() {
Bootstrap bootstrap = new Bootstrap(); // (1)
try {
bootstrap.group(workerGroup); // (2)
bootstrap.channel(NioSocketChannel.class); // (3)
bootstrap.option(ChannelOption.SO_KEEPALIVE, true); // (4)
bootstrap.handler(new ChannelInitializer<SocketChannel>() {
#Override
public void initChannel(SocketChannel ch) throws Exception {
ch.pipeline().addLast(new MyClientHandler());
}
});
ChannelFuture feature = bootstrap.connect(HOST, PORT).sync();
feature.addListener((future) -> {
System.out.println(dtuCode + " connected to server");
Channel channel = feature.channel();
ByteBuf buffer = Unpooled.buffer(256);
buffer.writeBytes(dtuCode.getBytes());
channel.writeAndFlush(buffer);
});
feature.channel().closeFuture().sync();
} catch (InterruptedException e) {
e.printStackTrace();
}
System.out.println("completed");
}
}
Can I get more connection.
I had try another solution after doing google research, but the channel will close automatically.

here is my another solution
package com.stepnetwork.iot.apsclient.application;
import io.netty.bootstrap.Bootstrap;
import io.netty.channel.Channel;
import io.netty.channel.ChannelInitializer;
import io.netty.channel.ChannelOption;
import io.netty.channel.EventLoopGroup;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.SocketChannel;
import io.netty.channel.socket.nio.NioSocketChannel;
import java.util.ArrayList;
import java.util.List;
/**
* Created by sam on 3/22/16.
*/
public class Test {
private static final String HOST = "192.168.54.36";
private static final int PORT = 30080;
public static void main(String[] args) throws InterruptedException {
EventLoopGroup workerGroup = new NioEventLoopGroup();
Bootstrap bootstrap = new Bootstrap(); // (1)
try {
bootstrap.group(workerGroup); // (2)
bootstrap.channel(NioSocketChannel.class); // (3)
bootstrap.option(ChannelOption.SO_KEEPALIVE, true); // (4)
bootstrap.handler(new ChannelInitializer<SocketChannel>() {
#Override
public void initChannel(SocketChannel ch) throws Exception {
ch.pipeline().addLast(new MyClientHandler());
}
});
List<Channel> channels = new ArrayList<>();
// create many connection here, but the channel will be closed atomically
for (int i = 0; i < 10000; i++) {
channels.add(bootstrap.connect(HOST, PORT).sync().channel());
}
} catch (InterruptedException e) {
e.printStackTrace();
}
while (true) {
Thread.sleep(Integer.MAX_VALUE);
}
}
}

Very Slow Apache httpserver response (httpcore 4.3.2 libs)

I am using httpcore libraries 4.3.2 to make a custom http server to communicate with some clients (android devices).
The clients manage to communicate (post an xml) with the server but the response of the server is very slow.
My code is based on the ElementalHttpServer of apache samples. Can i find somewhere else better samples for the httpcore libraries?
Also i can not find how to set the parameteres or to finetune the httpserver because the HttParams lib is deprecated.
If i use the com.sun.net.httpserver.HttpServer httpserver my clients are connecting without problem. It is better to stay with suns libs or to use apaches?
Thanks in advance.
This is the code i used:
import java.io.IOException;
import java.io.InterruptedIOException;
import java.net.ServerSocket;
import java.net.Socket;
import javax.net.ssl.SSLServerSocketFactory;
import org.apache.http.ConnectionClosedException;
import org.apache.http.HttpConnectionFactory;
import org.apache.http.HttpEntity;
import org.apache.http.HttpEntityEnclosingRequest;
import org.apache.http.HttpException;
import org.apache.http.HttpRequest;
import org.apache.http.HttpResponse;
import org.apache.http.HttpServerConnection;
import org.apache.http.HttpStatus;
import org.apache.http.entity.ContentType;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.DefaultBHttpServerConnection;
import org.apache.http.impl.DefaultBHttpServerConnectionFactory;
import org.apache.http.protocol.BasicHttpContext;
import org.apache.http.protocol.HttpContext;
import org.apache.http.protocol.HttpProcessor;
import org.apache.http.protocol.HttpProcessorBuilder;
import org.apache.http.protocol.HttpRequestHandler;
import org.apache.http.protocol.HttpService;
import org.apache.http.protocol.ResponseConnControl;
import org.apache.http.protocol.ResponseContent;
import org.apache.http.protocol.ResponseDate;
import org.apache.http.protocol.ResponseServer;
import org.apache.http.protocol.UriHttpRequestHandlerMapper;
import org.apache.http.util.EntityUtils;
public class Thread_Main_httpcore2 implements Runnable {
public Thread_Main_httpcore2() {
}//Thread_Main()
#Override
public void run() {
int port = 20010;
// Set up the HTTP protocol processor
HttpProcessor httpproc = HttpProcessorBuilder.create()
.add(new ResponseDate())
.add(new ResponseServer("Test/1.1"))
.add(new ResponseContent())
.add(new ResponseConnControl()).build();
// Set up request handlers
UriHttpRequestHandlerMapper reqistry = new UriHttpRequestHandlerMapper();
//// Set up the HTTP service
HttpService httpService = new HttpService(httpproc, reqistry);
reqistry.register("*", new Thread_Main_httpcore2.HttpReqHandler());
SSLServerSocketFactory sf = null;
try {
Thread t = new RequestListenerThread(port, httpService, sf);
t.setDaemon(false);
t.start();
} catch (Exception ex) {
ex.printStackTrace();
}
}
static class HttpReqHandler implements HttpRequestHandler {
public HttpReqHandler() {
super();
}
public void handle(
final HttpRequest request,
final HttpResponse response,
final HttpContext context) throws HttpException, IOException {
String xml_stream="";
if (request instanceof HttpEntityEnclosingRequest) {
HttpEntity entity = ((HttpEntityEnclosingRequest) request).getEntity();
byte[] entityContent;
if (entity == null) {
entityContent = new byte[0];
} else {
entityContent = EntityUtils.toByteArray(entity);
}
//byte[] entityContent = EntityUtils.toByteArray(entity);
System.out.println("Incoming entity content (bytes): " + entityContent.length);
xml_stream = new String(entityContent);
}
StringBuilder resp_xml = new StringBuilder();
resp_xml.append("Returns an xml to the client");
StringEntity entity;
try {
response.setStatusCode(HttpStatus.SC_OK);
entity = new StringEntity(resp_xml.toString(), ContentType.create("text/html", "UTF-8"));
response.setEntity(entity);
} catch (Exception ex_send_resp) {
System.out.println("HttpFileHandler.ex_send_resp "+ ex_send_resp.toString());
}
}
}
static class RequestListenerThread extends Thread {
private final HttpConnectionFactory<DefaultBHttpServerConnection> connFactory;
private final ServerSocket serversocket;
private final HttpService httpService;
public RequestListenerThread(
final int port,
final HttpService httpService,
final SSLServerSocketFactory sf) throws IOException {
this.connFactory = DefaultBHttpServerConnectionFactory.INSTANCE;
this.serversocket = sf != null ? sf.createServerSocket(port) : new ServerSocket(port);
this.httpService = httpService;
}
#Override
public void run() {
System.out.println("Listening on port " + this.serversocket.getLocalPort());
while (!Thread.interrupted()) {
try {
// Set up HTTP connection
Socket socket = this.serversocket.accept();
System.out.println("Incoming connection from " + socket.getInetAddress());
HttpServerConnection conn = this.connFactory.createConnection(socket);
// Start worker thread
Thread t = new WorkerThread(this.httpService, conn);
t.setDaemon(true);
t.start();
} catch (InterruptedIOException ex) {
break;
} catch (IOException e) {
System.err.println("I/O error initialising connection thread: "
+ e.getMessage());
break;
}
}
}
}
static class WorkerThread extends Thread {
private final HttpService httpservice;
private final HttpServerConnection conn;
public WorkerThread(
final HttpService httpservice,
final HttpServerConnection conn) {
super();
this.httpservice = httpservice;
this.conn = conn;
}
#Override
public void run() {
System.out.println("New connection thread");
HttpContext context = new BasicHttpContext(null);
try {
while (!Thread.interrupted() && this.conn.isOpen()) {
this.httpservice.handleRequest(this.conn, context);
}
} catch (ConnectionClosedException ex) {
System.err.println("Client closed connection");
} catch (IOException ex) {
System.err.println("I/O error: " + ex.getMessage());
} catch (HttpException ex) {
System.err.println("Unrecoverable HTTP protocol violation: " + ex.getMessage());
} finally {
try {
this.conn.shutdown();
} catch (IOException ignore) {
}
}
}
}
}

kryo serializing of class (task object) in apache spark returns null while de-serialization

I am using java spark API to write some test application . I am using a class which doesn't extends serializable interface . So to make the application work I am using kryo serializer to serialize the class . But the problem which I observed while debugging was that during the de-serialization the returned class object becomes null and in turn throws a null pointer exception . It seems to be closure problem where things are going wrong but not sure.Since I am new to this kind of serialization I don't know where to start digging.
Here is the code I am testing :
package org.apache.spark.examples;
import java.io.FileWriter;
import java.io.IOException;
import java.io.PrintWriter;
import java.net.InetAddress;
import java.net.UnknownHostException;
import org.apache.spark.SparkConf;
import org.apache.spark.api.java.JavaRDD;
import org.apache.spark.api.java.JavaSparkContext;
import org.apache.spark.api.java.function.Function;
/**
* Spark application to test the Serialization issue in spark
*/
public class Test {
static PrintWriter outputFileWriter;
static FileWriter file;
static JavaSparkContext ssc;
public static void main(String[] args) {
String inputFile = "/home/incubator-spark/examples/src/main/scala/org/apache/spark/examples/InputFile.txt";
String master = "local";
String jobName = "TestSerialization";
String sparkHome = "/home/test/Spark_Installation/spark-0.7.0";
String sparkJar = "/home/test/TestSerializationIssesInSpark/TestSparkSerIssueApp/target/TestSparkSerIssueApp-0.0.1-SNAPSHOT.jar";
SparkConf conf = new SparkConf();
conf.set("spark.closure.serializer","org.apache.spark.serializer.KryoSerializer");
conf.set("spark.kryo.registrator", "org.apache.spark.examples.MyRegistrator");
// create the Spark context
if(master.equals("local")){
ssc = new JavaSparkContext("local", jobName,conf);
//ssc = new JavaSparkContext("local", jobName);
} else {
ssc = new JavaSparkContext(master, jobName, sparkHome, sparkJar);
}
JavaRDD<String> testData = ssc.textFile(inputFile).cache();
final NotSerializableJavaClass notSerializableTestObject= new NotSerializableJavaClass("Hi ");
#SuppressWarnings({ "serial", "unchecked"})
JavaRDD<String> classificationResults = testData.map(
new Function<String, String>() {
#Override
public String call(String inputRecord) throws Exception {
if(!inputRecord.isEmpty()) {
//String[] pointDimensions = inputRecord.split(",");
String result = "";
try {
FileWriter file = new FileWriter("/home/test/TestSerializationIssesInSpark/results/test_result_" + (int) (Math.random() * 100));
PrintWriter outputFile = new PrintWriter(file);
InetAddress ip;
ip = InetAddress.getLocalHost();
outputFile.println("IP of the server: " + ip);
result = notSerializableTestObject.testMethod(inputRecord);
outputFile.println("Result: " + result);
outputFile.flush();
outputFile.close();
file.close();
} catch (UnknownHostException e) {
e.printStackTrace();
}
catch (IOException e1) {
e1.printStackTrace();
}
return result;
} else {
System.out.println("End of elements in the stream.");
String result = "End of elements in the input data";
return result;
}
}
}).cache();
long processedRecords = classificationResults.count();
ssc.stop();
System.out.println("sssssssssss"+processedRecords);
}
}
Here is the KryoRegistrator class
package org.apache.spark.examples;
import org.apache.spark.serializer.KryoRegistrator;
import com.esotericsoftware.kryo.Kryo;
public class MyRegistrator implements KryoRegistrator {
public void registerClasses(Kryo kryo) {
kryo.register(NotSerializableJavaClass.class);
}
}
Here is the class I am serializing :
package org.apache.spark.examples;
public class NotSerializableJavaClass {
public String testVariable;
public NotSerializableJavaClass(String testVariable) {
super();
this.testVariable = testVariable;
}
public String testMethod(String vartoAppend){
return this.testVariable + vartoAppend;
}
}

This is because spark.closure.serializer only supports the Java serializer. See http://spark.apache.org/docs/latest/configuration.html about spark.closure.serializer