I'm using Jetty 8.1.1 Websocket client api.
I need to update the headers with ("Sec-WebSocket-Protocol", "xsCrossfire") and ("Authorization", "Basic TLVWQMZqRr2hasYnZoI=")
WebSocketClientFactory factory = new WebSocketClientFactory();
factory.start();
client = factory.newWebSocketClient();
client.getCookies().put("Sec-WebSocket-Protocol", "xsCrossfire");
client.getCookies().put("Authorization", "Basic TLVWQMZqRr2hasYnZoI=");
Future<Connection> conn = client.open(uri, (WebSocket) this);
System.out.printf("Connecting to : %s%n", uri);
request looks:
Host: iltlvl262:8000\r\n
Upgrade: websocket\r\n
Connection: Upgrade\r\n
Sec-WebSocket-Version: 13\r\n
Sec-WebSocket-Key: FHKTsICO2vqGCxXVwLkH4Q==\r\n
Cookie: Sec-WebSocket-Protocol=xsCrossfire\r\n
Cookie: Authorization="Basic TLVWQMZqRr2hasYnZoI="\r\n
expected request:
Host: iltlvl262:8000\r\n
Upgrade: websocket\r\n
Connection: Upgrade\r\n
Sec-WebSocket-Version: 13\r\n
Sec-WebSocket-Key: FHKTsICO2vqGCxXVwLkH4Q==\r\n
Sec-WebSocket-Protocol: xsCrossfire\r\n
Authorization: "Basic TLVWQMZqRr2hasYnZoI="\r\n
how do I implement handshake in version 8.1.1 correctly?
Some good news and some bad news.
First, the Good news:
To set the Sec-WebSocket-Protocol header use the following.
client.setProtocol("xsCrossfire");
before you use client.open()
Next, the Bad news:
With Jetty 8.x you cannot set arbitrary non-websocket headers. This was due to how early experimental drafts of WebSocket were written. You simply were not allowed to set arbitrary headers per the early draft specs, so the implementation back in the Jetty 8.x days just didn't allow it.
However, with the finalization of RFC6455 (the official WebSocket spec) things changed, all of those changes were rolled into the Jetty 9.x codebase. Which is 100% RFC6455 compliant. (Note: Jetty 8 is 100% compliant to RFC6455 on the server side. Jetty 8 is also 100% compatible on the RFC6455 protocol use for both server and client. However, Jetty 8 is only partially compliant on the client side, from a features and API point of view.)
The decision with Jetty 7 and Jetty 8 was made to keep the old experimental drafts around for those early adopters and old browsers (Safari 5.x) that still used them. This decision prevented us from allowing behaviors that are specifically prevented in the old experimental drafts.
Starting with Jetty 9.x all old experimental drafts of websocket were dropped, leaving only RFC6455 to support, which allowed Jetty to open up more features that were previously disallowed. This includes arbitrary headers on the WebSocketClient.
Example of Jetty 9.1 WebSocket Client
import java.io.IOException;
import java.net.URI;
import java.util.concurrent.Future;
import org.eclipse.jetty.websocket.api.Session;
import org.eclipse.jetty.websocket.api.WebSocketAdapter;
import org.eclipse.jetty.websocket.client.ClientUpgradeRequest;
import org.eclipse.jetty.websocket.client.WebSocketClient;
public class ExampleClient
{
public static class ExampleSocket extends WebSocketAdapter
{
#Override
public void onWebSocketText(String message)
{
try
{
// echo the message
getRemote().sendString(message);
}
catch (IOException e)
{
e.printStackTrace();
}
}
}
public static void main(String[] args)
{
try
{
new ExampleClient().demo();
}
catch (Throwable t)
{
t.printStackTrace(System.err);
}
}
public void demo() throws Exception
{
WebSocketClient client = new WebSocketClient();
try
{
client.start();
ClientUpgradeRequest request = new ClientUpgradeRequest();
request.setSubProtocols("xsCrossfire");
request.setHeader("Authorization","Basic TLVWQMZqRr2hasYnZoI=");
URI wsUri = URI.create("ws://iltlvl262:8000/echo");
ExampleSocket socket = new ExampleSocket();
Future<Session> future = client.connect(socket,wsUri,request);
future.get(); // wait for connect
socket.getRemote().sendString("hello"); // send message
}
finally
{
client.stop();
}
}
}
Also note, that starting with Jetty 9.1, even the javax.websocket (JSR-356) API is fully supported.
Same example using javax.websocket on Jetty 9.1
import java.net.URI;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import javax.websocket.ClientEndpoint;
import javax.websocket.ContainerProvider;
import javax.websocket.OnMessage;
import javax.websocket.Session;
import javax.websocket.WebSocketContainer;
public class ExampleClient
{
#ClientEndpoint(subprotocols = { "xsCrossfire" },
configurator = ExampleClient.Configurator.class)
public static class ExampleSocket
{
#OnMessage
public String onMessage(String msg)
{
return msg; // echo
}
}
public static class Configurator
extends javax.websocket.ClientEndpointConfig.Configurator
{
#Override
public void beforeRequest(Map<String, List<String>> headers)
{
List<String> authvalues = new ArrayList<>();
authvalues.add("Basic TLVWQMZqRr2hasYnZoI=");
headers.put("Authorization", authvalues);
super.beforeRequest(headers);
}
}
public static void main(String[] args)
{
try
{
new ExampleClient().demo();
}
catch (Throwable t)
{
t.printStackTrace(System.err);
}
}
public void demo() throws Exception
{
WebSocketContainer client = ContainerProvider.getWebSocketContainer();
ExampleSocket socket = new ExampleSocket();
URI wsUri = URI.create("ws://iltlvl262:8000/echo");
Session session = client.connectToServer(socket,wsUri);
session.getAsyncRemote().sendText("Hello");
}
}
I'm trying to get hold of some injected context (for example Session or HttpServletRequest) in a Servlet I've written, running on Grizzly, but nothing I do seems to work. The whole process seems to stall rather prematurely with the following error:
SEVERE: Missing dependency for field: javax.servlet.http.HttpServletRequest com.test.server.LolCat.hsr
The server is dead simple, it consists of two files, the static entry point (Main.java):
package com.test.server;
import java.io.IOException;
import java.net.URI;
import javax.ws.rs.core.UriBuilder;
import org.glassfish.grizzly.http.server.HttpServer;
import com.sun.jersey.api.container.grizzly2.GrizzlyServerFactory;
import com.sun.jersey.api.core.ClassNamesResourceConfig;
import com.sun.jersey.api.core.ResourceConfig;
public class Main {
private static URI getBaseURI() {
return UriBuilder.fromUri("http://localhost/").port(8080).build();
}
public static final URI BASE_URI = getBaseURI();
public static void main(String[] args) throws IOException {
ResourceConfig rc = new ClassNamesResourceConfig(LolCat.class);
HttpServer httpServer = GrizzlyServerFactory.createHttpServer(BASE_URI, rc);
System.in.read();
httpServer.stop();
}
}
and the serlvet (LolCat.java):
package com.test.server;
import javax.servlet.http.HttpServletRequest;
import javax.ws.rs.GET;
import javax.ws.rs.Path;
import javax.ws.rs.core.Context;
#Path(value = "/lol")
public class LolCat {
#Context HttpServletRequest hsr;
#GET
#Path(value="/cat")
public String list() {
return "meow";
}
}
Specifically, it's the #Context-line in the above source file that is the source and solution to all my problems. I need it, and according to everything I've read about Jersey and Servlets it should work, but alas it does not. I've also tried using GrizzlyWebContainerFactory instead of the GrizzlyServerFactory, but to no avail.
For reference, the project is compiled with the following dependencies:
org.glassfish.grizzly:grizzly-framework:jar:2.2.21
org.glassfish.grizzly:grizzly-http:jar:2.2.21
org.glassfish.grizzly:grizzly-http-servlet:jar:2.2.21
org.glassfish.grizzly:grizzly-http-server:jar:2.2.21
com.sun.jersey:jersey-server:jar:1.17
com.sun.jersey:jersey-servlet:jar:1.17
com.sun.jersey:jersey-core:jar:1.17
javax.servlet:javax.servlet-api:jar:2.5.0
com.sun.jersey:jersey-grizzly2:jar:1.17
com.sun.jersey:jersey-grizzly2-servlet:jar:1.17
asm:asm:jar:3.3.1
This Main class works fine for me:
package com.test.server;
import com.sun.jersey.api.container.grizzly2.GrizzlyServerFactory;
import java.io.IOException;
import java.net.URI;
import javax.ws.rs.core.UriBuilder;
import com.sun.jersey.api.core.ClassNamesResourceConfig;
import com.sun.jersey.spi.container.servlet.ServletContainer;
import org.glassfish.grizzly.http.server.HttpHandler;
import org.glassfish.grizzly.http.server.HttpServer;
import org.glassfish.grizzly.http.server.Request;
import org.glassfish.grizzly.http.server.Response;
import org.glassfish.grizzly.servlet.ServletRegistration;
import org.glassfish.grizzly.servlet.WebappContext;
public class Main {
private static final String JERSEY_SERVLET_CONTEXT_PATH = "";
private static URI getBaseURI() {
return UriBuilder.fromUri("http://localhost").port(8080).path("/").build();
}
public static final URI BASE_URI = getBaseURI();
public static void main(String[] args) throws IOException {
// Create HttpServer and register dummy "not found" HttpHandler
HttpServer httpServer = GrizzlyServerFactory.createHttpServer(BASE_URI, new HttpHandler() {
#Override
public void service(Request rqst, Response rspns) throws Exception {
rspns.setStatus(404, "Not found");
rspns.getWriter().write("404: not found");
}
});
// Initialize and register Jersey Servlet
WebappContext context = new WebappContext("WebappContext", JERSEY_SERVLET_CONTEXT_PATH);
ServletRegistration registration = context.addServlet("ServletContainer", ServletContainer.class);
registration.setInitParameter(ServletContainer.RESOURCE_CONFIG_CLASS,
ClassNamesResourceConfig.class.getName());
registration.setInitParameter(ClassNamesResourceConfig.PROPERTY_CLASSNAMES, LolCat.class.getName());
registration.addMapping("/*");
context.deploy(httpServer);
System.in.read();
httpServer.stop();
}
}
Try http://localhost:8080/lol/cat in your browser.
You can change JERSEY_SERVLET_CONTEXT_PATH to update Servlet's context-path.
As per developers explanations - Grizzly is not fully compliant to JAX-RS 2.0 so there will be no official contexts injections/wrapping. See Jersey Bug-1960
Applicable for Jersey + Grizzly version 2.7+
Luckily there is a way to inject Grizzly request/response objects. Kind of tricky but works
Code sample provided in one of Jersey's unit tests. See Jersey container test
So code fragment will be:
import javax.inject.Inject;
import javax.inject.Provider;
public someclass {
#Inject
private Provider<Request> grizzlyRequestProvider;
public void method() {
if (grizzlyRequestProvider != null) {
Request httpRequest = grizzlyRequestProvider.get();
// Extract what you need
}
}
}
Works fine both for filters and service methods
You can also manually register a ResourceContext
HttpServer httpServer = GrizzlyHttpServerFactory.createHttpServer(getBaseURI());
WebappContext context = new WebappContext("WebappContext", "/api");
ServletRegistration registration = context.addServlet("ServletContainer",
new ServletContainer(config));
registration.addMapping("/*");
context.deploy(httpServer);
Where config is your resource context.
Try something like this :-
public class Main {
private static URI getBaseURI() {
return UriBuilder.fromUri("http://localhost/").port(8080).build();
}
public static void main(String[] args) throws IOException {
ResourceConfig rc = new ResourceConfig().packages("com.example");//path to you class files
HttpServer httpServer = GrizzlyHttpServerFactory.createHttpServer(getBaseURI(), rc);
System.in.read();
httpServer.stop();
}
}
I am copying the simplest web service example from CXF; it steps through writing an interface, then an implementation file, to say hello to a name provided by the webservice consumer. I changed a package name and the method name because I wanted to see where things showed up; if you name everything HelloWorld you can't see what is method, package, class, etc.
Those instructions include a program to publish the web service. After I do that, putting the URL
http://localhost:9000/helloWorld?wsdl
in a browser displays a wsdl file that contains enough stuff the way I spelled it to convince me that it was generated from my code. I assume, based on this, that both the WSDL generation and the publication worked.
This is the service interface:
package hw;
import javax.jws.WebParam;
import javax.jws.WebService;
#WebService
public interface HelloWorld
{
String sayHi(#WebParam(name="firstName") String firstName);
}
This is the service implementation:
package hwimpl;
import javax.jws.WebService;
#WebService(endpointInterface = "hw.HelloWorld", serviceName = "HelloWorld")
public class HelloWorldImpl
{
static public void say(String msg) { System.out.println(msg); }
public String sayHi(String firstName)
{ say ("sayHi called with " + firstName);
return "Hello " + firstName + " from the World.";
}
}
And this is the publishing program:
package hwimpl;
import javax.xml.ws.Endpoint;
public class PublishHelloWorldService
{
protected PublishHelloWorldService() throws Exception
{
// START SNIPPET: publish
System.out.println("Starting Server");
HelloWorldImpl implementor = new HelloWorldImpl();
String address = "http://localhost:9000/helloWorld";
Endpoint.publish(address, implementor);
// END SNIPPET: publish
}
public static void main(String args[]) throws Exception
{
new PublishHelloWorldService();
System.out.println("Server ready...");
Thread.sleep(5 * 60 * 1000);
System.out.println("Server exiting");
System.exit(0);
}
}
Now I compile and run this program:
package client;
import hw.HelloWorld;
import javax.xml.namespace.QName;
import javax.xml.ws.Service;
import javax.xml.ws.soap.SOAPBinding;
public final class HelloWorldClient
{
private static final QName SERVICE_NAME = new QName("http://server.hw.demo/", "HelloWorld");
private static final QName PORT_NAME = new QName("http://server.hw.demo/", "HelloWorldPort");
private HelloWorldClient()
{
}
public static void main(String args[]) throws Exception
{
Service service = Service.create(SERVICE_NAME);
String endpointAddress = "http://localhost:9000/helloWorld";
// If web service deployed on Tomcat deployment, endpoint should be changed
// to:
// String
// endpointAddress =
// "http://localhost:8080/java_first_jaxws/services/hello_world";
// Add a port to the Service
service.addPort(PORT_NAME, SOAPBinding.SOAP11HTTP_BINDING, endpointAddress);
HelloWorld hw = service.getPort(HelloWorld.class);
System.out.println(hw.sayHi("Albert"));
}
}
and I get this error:
Exception in thread "main" javax.xml.ws.WebServiceException: Could not send Message.
at org.apache.cxf.jaxws.JaxWsClientProxy.invoke(JaxWsClientProxy.java:135)
at com.sun.proxy.$Proxy20.sayHi(Unknown Source)
at client.HelloWorldClient.main(HelloWorldClient.java:37)
Caused by: java.net.MalformedURLException: Invalid address. Endpoint address cannot be null.
at org.apache.cxf.transport.http.HTTPConduit.getURL(HTTPConduit.java:872)
at org.apache.cxf.transport.http.HTTPConduit.getURL(HTTPConduit.java:854)
at org.apache.cxf.transport.http.HTTPConduit.setupURL(HTTPConduit.java:800)
at org.apache.cxf.transport.http.HTTPConduit.prepare(HTTPConduit.java:548)
at org.apache.cxf.interceptor.MessageSenderInterceptor.handleMessage(MessageSenderInterceptor.java:46)
at org.apache.cxf.phase.PhaseInterceptorChain.doIntercept(PhaseInterceptorChain.java:255)
at org.apache.cxf.endpoint.ClientImpl.invoke(ClientImpl.java:516)
at org.apache.cxf.endpoint.ClientImpl.invoke(ClientImpl.java:313)
at org.apache.cxf.endpoint.ClientImpl.invoke(ClientImpl.java:265)
at org.apache.cxf.frontend.ClientProxy.invokeSync(ClientProxy.java:73)
at org.apache.cxf.jaxws.JaxWsClientProxy.invoke(JaxWsClientProxy.java:124)
... 2 more
I am running the programs -- both publish and client -- from eclipse. The eclipse is set up with proxies for http and https in Window / Preferences; I removed the one for http before running the client, but it did not change the message.
It is in fact a tomcat server; I tried the alternate URL in the publish program with no change.
I don't run tomcat from within eclipse in this case; I run it by itself on my machine and then run the publish program (from eclipse), verify the url that displays the wsdl works correctly, and then run the client program (from eclipse) and get my error.
Can someone tell me what I'm doing wrong? I've seen other posts on this exact error message, but none of the answers were definitive and I appear to have tried them all.
Not sure this is your problem.
I've sometimes had problems with eclipse not being able to run tomcat applications on a running tomcat as you describe in your example.
What I sometimes have to do when working with tomcat and eclipse is either
have a running tomcat (windows service) and then export my eclipse application to that tomcat
stop the running tomcat on that port from windows services and start the tomcat from inside eclipse when running the program.
For some reason eclipse seems to have problems with an already running tomcat.
Is there a way to create a very basic HTTP server (supporting only GET/POST) in Java using just the Java SE API, without writing code to manually parse HTTP requests and manually format HTTP responses? The Java SE API nicely encapsulates the HTTP client functionality in HttpURLConnection, but is there an analog for HTTP server functionality?
Just to be clear, the problem I have with a lot of ServerSocket examples I've seen online is that they do their own request parsing/response formatting and error handling, which is tedious, error-prone, and not likely to be comprehensive, and I'm trying to avoid it for those reasons.
Since Java SE 6, there's a builtin HTTP server in Sun Oracle JRE. The Java 9 module name is jdk.httpserver. The com.sun.net.httpserver package summary outlines the involved classes and contains examples.
Here's a kickoff example copypasted from their docs. You can just copy'n'paste'n'run it on Java 6+.
(to all people trying to edit it nonetheless, because it's an ugly piece of code, please don't, this is a copy paste, not mine, moreover you should never edit quotations unless they have changed in the original source)
package com.stackoverflow.q3732109;
import java.io.IOException;
import java.io.OutputStream;
import java.net.InetSocketAddress;
import com.sun.net.httpserver.HttpExchange;
import com.sun.net.httpserver.HttpHandler;
import com.sun.net.httpserver.HttpServer;
public class Test {
public static void main(String[] args) throws Exception {
HttpServer server = HttpServer.create(new InetSocketAddress(8000), 0);
server.createContext("/test", new MyHandler());
server.setExecutor(null); // creates a default executor
server.start();
}
static class MyHandler implements HttpHandler {
#Override
public void handle(HttpExchange t) throws IOException {
String response = "This is the response";
t.sendResponseHeaders(200, response.length());
OutputStream os = t.getResponseBody();
os.write(response.getBytes());
os.close();
}
}
}
Noted should be that the response.length() part in their example is bad, it should have been response.getBytes().length. Even then, the getBytes() method must explicitly specify the charset which you then specify in the response header. Alas, albeit misguiding to starters, it's after all just a basic kickoff example.
Execute it and go to http://localhost:8000/test and you'll see the following response:
This is the response
As to using com.sun.* classes, do note that this is, in contrary to what some developers think, absolutely not forbidden by the well known FAQ Why Developers Should Not Write Programs That Call 'sun' Packages. That FAQ concerns the sun.* package (such as sun.misc.BASE64Encoder) for internal usage by the Oracle JRE (which would thus kill your application when you run it on a different JRE), not the com.sun.* package. Sun/Oracle also just develop software on top of the Java SE API themselves like as every other company such as Apache and so on. Moreover, this specific HttpServer must be present in every JDK so there is absolutely no means of "portability" issue like as would happen with sun.* package. Using com.sun.* classes is only discouraged (but not forbidden) when it concerns an implementation of a certain Java API, such as GlassFish (Java EE impl), Mojarra (JSF impl), Jersey (JAX-RS impl), etc.
Check out NanoHttpd
NanoHTTPD is a light-weight HTTP server designed for embedding in other applications, released under a Modified BSD licence.
It is being developed at Github and uses Apache Maven for builds & unit testing"
The com.sun.net.httpserver solution is not portable across JREs. Its better to use the official webservices API in javax.xml.ws to bootstrap a minimal HTTP server...
import java.io._
import javax.xml.ws._
import javax.xml.ws.http._
import javax.xml.transform._
import javax.xml.transform.stream._
#WebServiceProvider
#ServiceMode(value=Service.Mode.PAYLOAD)
class P extends Provider[Source] {
def invoke(source: Source) = new StreamSource( new StringReader("<p>Hello There!</p>"));
}
val address = "http://127.0.0.1:8080/"
Endpoint.create(HTTPBinding.HTTP_BINDING, new P()).publish(address)
println("Service running at "+address)
println("Type [CTRL]+[C] to quit!")
Thread.sleep(Long.MaxValue)
EDIT: this actually works! The above code looks like Groovy or something. Here is a translation to Java which I tested:
import java.io.*;
import javax.xml.ws.*;
import javax.xml.ws.http.*;
import javax.xml.transform.*;
import javax.xml.transform.stream.*;
#WebServiceProvider
#ServiceMode(value = Service.Mode.PAYLOAD)
public class Server implements Provider<Source> {
public Source invoke(Source request) {
return new StreamSource(new StringReader("<p>Hello There!</p>"));
}
public static void main(String[] args) throws InterruptedException {
String address = "http://127.0.0.1:8080/";
Endpoint.create(HTTPBinding.HTTP_BINDING, new Server()).publish(address);
System.out.println("Service running at " + address);
System.out.println("Type [CTRL]+[C] to quit!");
Thread.sleep(Long.MAX_VALUE);
}
}
I like this question because this is an area where there's continuous innovation and there's always a need to have a light server especially when talking about embedded servers in small(er) devices. I think answers fall into two broad groups.
Thin-server: server-up static content with minimal processing, context or session processing.
Small-server: ostensibly a has many httpD-like server qualities with as small a footprint as you can get away with.
While I might consider HTTP libraries like: Jetty, Apache Http Components, Netty and others to be more like a raw HTTP processing facilities. The labelling is very subjective, and depends on the kinds of thing you've been call-on to deliver for small-sites. I make this distinction in the spirit of the question, particularly the remark about...
"...without writing code to manually parse HTTP requests and manually format HTTP responses..."
These raw tools let you do that (as described in other answers). They don't really lend themselves to a ready-set-go style of making a light, embedded or mini-server. A mini-server is something that can give you similar functionality to a full-function web server (like say, Tomcat) without bells and whistles, low volume, good performance 99% of the time. A thin-server seems closer to the original phrasing just a bit more than raw perhaps with a limited subset functionality, enough to make you look good 90% of the time. My idea of raw would be makes me look good 75% - 89% of the time without extra design and coding. I think if/when you reach the level of WAR files, we've left the "small" for bonsi servers that looks like everything a big server does smaller.
Thin-server options
Grizzly
UniRest (multiple-languages)
NanoHTTPD (just one file)
Mini-server options:
Spark Java ... Good things are possible with lots of helper constructs like Filters, Templates, etc.
MadVoc ... aims to be bonsai and could well be such ;-)
Among the other things to consider, I'd include authentication, validation, internationalisation, using something like FreeMaker or other template tool to render page output. Otherwise managing HTML editing and parameterisation is likely to make working with HTTP look like noughts-n-crosses. Naturally it all depends on how flexible you need to be. If it's a menu-driven FAX machine it can be very simple. The more interactions, the 'thicker' your framework needs to be. Good question, good luck!
Have a look at the "Jetty" web server Jetty. Superb piece of Open Source software that would seem to meet all your requirments.
If you insist on rolling your own then have a look at the "httpMessage" class.
Once upon a time I was looking for something similar - a lightweight yet fully functional HTTP server that I could easily embed and customize. I found two types of potential solutions:
Full servers that are not all that lightweight or simple (for an extreme definition of lightweight.)
Truly lightweight servers that aren't quite HTTP servers, but glorified ServerSocket examples that are not even remotely RFC-compliant and don't support commonly needed basic functionality.
So... I set out to write JLHTTP - The Java Lightweight HTTP Server.
You can embed it in any project as a single (if rather long) source file, or as a ~50K jar (~35K stripped) with no dependencies. It strives to be RFC-compliant and includes extensive documentation and many useful features while keeping bloat to a minimum.
Features include: virtual hosts, file serving from disk, mime type mappings via standard mime.types file, directory index generation, welcome files, support for all HTTP methods, conditional ETags and If-* header support, chunked transfer encoding, gzip/deflate compression, basic HTTPS (as provided by the JVM), partial content (download continuation), multipart/form-data handling for file uploads, multiple context handlers via API or annotations, parameter parsing (query string or x-www-form-urlencoded body), etc.
I hope others find it useful :-)
Spark is the simplest, here is a quick start guide: http://sparkjava.com/
All the above answers details about Single main threaded Request Handler.
setting:
server.setExecutor(java.util.concurrent.Executors.newCachedThreadPool());
Allows multiple request serving via multiple threads using executor service.
So the end code will be something like below:
import java.io.IOException;
import java.io.OutputStream;
import java.net.InetSocketAddress;
import com.sun.net.httpserver.HttpExchange;
import com.sun.net.httpserver.HttpHandler;
import com.sun.net.httpserver.HttpServer;
public class App {
public static void main(String[] args) throws Exception {
HttpServer server = HttpServer.create(new InetSocketAddress(8000), 0);
server.createContext("/test", new MyHandler());
//Thread control is given to executor service.
server.setExecutor(java.util.concurrent.Executors.newCachedThreadPool());
server.start();
}
static class MyHandler implements HttpHandler {
#Override
public void handle(HttpExchange t) throws IOException {
String response = "This is the response";
long threadId = Thread.currentThread().getId();
System.out.println("I am thread " + threadId );
response = response + "Thread Id = "+threadId;
t.sendResponseHeaders(200, response.length());
OutputStream os = t.getResponseBody();
os.write(response.getBytes());
os.close();
}
}
}
It's possible to create an httpserver that provides basic support for J2EE servlets with just the JDK and the servlet api in a just a few lines of code.
I've found this very useful for unit testing servlets, as it starts much faster than other lightweight containers (we use jetty for production).
Most very lightweight httpservers do not provide support for servlets, but we need them, so I thought I'd share.
The below example provides basic servlet support, or throws and UnsupportedOperationException for stuff not yet implemented. It uses the com.sun.net.httpserver.HttpServer for basic http support.
import java.io.*;
import java.lang.reflect.*;
import java.net.InetSocketAddress;
import java.util.*;
import javax.servlet.*;
import javax.servlet.http.*;
import com.sun.net.httpserver.HttpExchange;
import com.sun.net.httpserver.HttpHandler;
import com.sun.net.httpserver.HttpServer;
#SuppressWarnings("deprecation")
public class VerySimpleServletHttpServer {
HttpServer server;
private String contextPath;
private HttpHandler httpHandler;
public VerySimpleServletHttpServer(String contextPath, HttpServlet servlet) {
this.contextPath = contextPath;
httpHandler = new HttpHandlerWithServletSupport(servlet);
}
public void start(int port) throws IOException {
InetSocketAddress inetSocketAddress = new InetSocketAddress(port);
server = HttpServer.create(inetSocketAddress, 0);
server.createContext(contextPath, httpHandler);
server.setExecutor(null);
server.start();
}
public void stop(int secondsDelay) {
server.stop(secondsDelay);
}
public int getServerPort() {
return server.getAddress().getPort();
}
}
final class HttpHandlerWithServletSupport implements HttpHandler {
private HttpServlet servlet;
private final class RequestWrapper extends HttpServletRequestWrapper {
private final HttpExchange ex;
private final Map<String, String[]> postData;
private final ServletInputStream is;
private final Map<String, Object> attributes = new HashMap<>();
private RequestWrapper(HttpServletRequest request, HttpExchange ex, Map<String, String[]> postData, ServletInputStream is) {
super(request);
this.ex = ex;
this.postData = postData;
this.is = is;
}
#Override
public String getHeader(String name) {
return ex.getRequestHeaders().getFirst(name);
}
#Override
public Enumeration<String> getHeaders(String name) {
return new Vector<String>(ex.getRequestHeaders().get(name)).elements();
}
#Override
public Enumeration<String> getHeaderNames() {
return new Vector<String>(ex.getRequestHeaders().keySet()).elements();
}
#Override
public Object getAttribute(String name) {
return attributes.get(name);
}
#Override
public void setAttribute(String name, Object o) {
this.attributes.put(name, o);
}
#Override
public Enumeration<String> getAttributeNames() {
return new Vector<String>(attributes.keySet()).elements();
}
#Override
public String getMethod() {
return ex.getRequestMethod();
}
#Override
public ServletInputStream getInputStream() throws IOException {
return is;
}
#Override
public BufferedReader getReader() throws IOException {
return new BufferedReader(new InputStreamReader(getInputStream()));
}
#Override
public String getPathInfo() {
return ex.getRequestURI().getPath();
}
#Override
public String getParameter(String name) {
String[] arr = postData.get(name);
return arr != null ? (arr.length > 1 ? Arrays.toString(arr) : arr[0]) : null;
}
#Override
public Map<String, String[]> getParameterMap() {
return postData;
}
#Override
public Enumeration<String> getParameterNames() {
return new Vector<String>(postData.keySet()).elements();
}
}
private final class ResponseWrapper extends HttpServletResponseWrapper {
final ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
final ServletOutputStream servletOutputStream = new ServletOutputStream() {
#Override
public void write(int b) throws IOException {
outputStream.write(b);
}
};
private final HttpExchange ex;
private final PrintWriter printWriter;
private int status = HttpServletResponse.SC_OK;
private ResponseWrapper(HttpServletResponse response, HttpExchange ex) {
super(response);
this.ex = ex;
printWriter = new PrintWriter(servletOutputStream);
}
#Override
public void setContentType(String type) {
ex.getResponseHeaders().add("Content-Type", type);
}
#Override
public void setHeader(String name, String value) {
ex.getResponseHeaders().add(name, value);
}
#Override
public javax.servlet.ServletOutputStream getOutputStream() throws IOException {
return servletOutputStream;
}
#Override
public void setContentLength(int len) {
ex.getResponseHeaders().add("Content-Length", len + "");
}
#Override
public void setStatus(int status) {
this.status = status;
}
#Override
public void sendError(int sc, String msg) throws IOException {
this.status = sc;
if (msg != null) {
printWriter.write(msg);
}
}
#Override
public void sendError(int sc) throws IOException {
sendError(sc, null);
}
#Override
public PrintWriter getWriter() throws IOException {
return printWriter;
}
public void complete() throws IOException {
try {
printWriter.flush();
ex.sendResponseHeaders(status, outputStream.size());
if (outputStream.size() > 0) {
ex.getResponseBody().write(outputStream.toByteArray());
}
ex.getResponseBody().flush();
} catch (Exception e) {
e.printStackTrace();
} finally {
ex.close();
}
}
}
public HttpHandlerWithServletSupport(HttpServlet servlet) {
this.servlet = servlet;
}
#SuppressWarnings("deprecation")
#Override
public void handle(final HttpExchange ex) throws IOException {
byte[] inBytes = getBytes(ex.getRequestBody());
ex.getRequestBody().close();
final ByteArrayInputStream newInput = new ByteArrayInputStream(inBytes);
final ServletInputStream is = new ServletInputStream() {
#Override
public int read() throws IOException {
return newInput.read();
}
};
Map<String, String[]> parsePostData = new HashMap<>();
try {
parsePostData.putAll(HttpUtils.parseQueryString(ex.getRequestURI().getQuery()));
// check if any postdata to parse
parsePostData.putAll(HttpUtils.parsePostData(inBytes.length, is));
} catch (IllegalArgumentException e) {
// no postData - just reset inputstream
newInput.reset();
}
final Map<String, String[]> postData = parsePostData;
RequestWrapper req = new RequestWrapper(createUnimplementAdapter(HttpServletRequest.class), ex, postData, is);
ResponseWrapper resp = new ResponseWrapper(createUnimplementAdapter(HttpServletResponse.class), ex);
try {
servlet.service(req, resp);
resp.complete();
} catch (ServletException e) {
throw new IOException(e);
}
}
private static byte[] getBytes(InputStream in) throws IOException {
ByteArrayOutputStream out = new ByteArrayOutputStream();
byte[] buffer = new byte[1024];
while (true) {
int r = in.read(buffer);
if (r == -1)
break;
out.write(buffer, 0, r);
}
return out.toByteArray();
}
#SuppressWarnings("unchecked")
private static <T> T createUnimplementAdapter(Class<T> httpServletApi) {
class UnimplementedHandler implements InvocationHandler {
#Override
public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
throw new UnsupportedOperationException("Not implemented: " + method + ", args=" + Arrays.toString(args));
}
}
return (T) Proxy.newProxyInstance(UnimplementedHandler.class.getClassLoader(),
new Class<?>[] { httpServletApi },
new UnimplementedHandler());
}
}
You may also have a look at some NIO application framework such as:
Netty: http://jboss.org/netty
Apache Mina: http://mina.apache.org/ or its subproject AsyncWeb: http://mina.apache.org/asyncweb/
This code is better than ours, you only need to add 2 libs: javax.servelet.jar and org.mortbay.jetty.jar.
Class Jetty:
package jetty;
import java.util.logging.Level;
import java.util.logging.Logger;
import org.mortbay.http.SocketListener;
import org.mortbay.jetty.Server;
import org.mortbay.jetty.servlet.ServletHttpContext;
public class Jetty {
public static void main(String[] args) {
try {
Server server = new Server();
SocketListener listener = new SocketListener();
System.out.println("Max Thread :" + listener.getMaxThreads() + " Min Thread :" + listener.getMinThreads());
listener.setHost("localhost");
listener.setPort(8070);
listener.setMinThreads(5);
listener.setMaxThreads(250);
server.addListener(listener);
ServletHttpContext context = (ServletHttpContext) server.getContext("/");
context.addServlet("/MO", "jetty.HelloWorldServlet");
server.start();
server.join();
/*//We will create our server running at http://localhost:8070
Server server = new Server();
server.addListener(":8070");
//We will deploy our servlet to the server at the path '/'
//it will be available at http://localhost:8070
ServletHttpContext context = (ServletHttpContext) server.getContext("/");
context.addServlet("/MO", "jetty.HelloWorldServlet");
server.start();
*/
} catch (Exception ex) {
Logger.getLogger(Jetty.class.getName()).log(Level.SEVERE, null, ex);
}
}
}
Servlet class:
package jetty;
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class HelloWorldServlet extends HttpServlet
{
#Override
protected void doGet(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse) throws ServletException, IOException
{
String appid = httpServletRequest.getParameter("appid");
String conta = httpServletRequest.getParameter("conta");
System.out.println("Appid : "+appid);
System.out.println("Conta : "+conta);
httpServletResponse.setContentType("text/plain");
PrintWriter out = httpServletResponse.getWriter();
out.println("Hello World!");
out.close();
}
}
I can strongly recommend looking into Simple, especially if you don't need Servlet capabilities but simply access to the request/reponse objects. If you need REST you can put Jersey on top of it, if you need to output HTML or similar there's Freemarker. I really love what you can do with this combination, and there is relatively little API to learn.
Starting in Java 18, you can create simple web servers with Java standard library:
class Main {
public static void main(String[] args) {
var port = 8000;
var rootDirectory = Path.of("C:/Users/Mahozad/Desktop/");
var outputLevel = OutputLevel.VERBOSE;
var server = SimpleFileServer.createFileServer(
new InetSocketAddress(port),
rootDirectory,
outputLevel
);
server.start();
}
}
This will, by default, show a directory listing of the root directory you specified. You can place an index.html file (and other assets like CSS and JS files) in that directory to show them instead.
Example (I put these in Desktop which was specified as my directory root above):
index.html:
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Java 18 Simple Web Server</title>
<link rel="stylesheet" href="styles.css">
<style>h1 { color: blue; }</style>
<script src="scripts.js" defer>
let element = document.getElementsByTagName("h1")[0];
element.style.fontSize = "48px";
</script>
</head>
<body>
<h1>I'm <i>index.html</i> in the root directory.</h1>
</body>
</html>
Sidenote
For Java standard library HTTP client, see the post Java 11 new HTTP Client API.
An example of a very basic HTTP server on TCP sockets level:
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.InetAddress;
import java.net.ServerSocket;
import java.net.Socket;
public class NaiveHttpServer {
public static void main(String[] args) throws IOException {
String hostname = InetAddress.getLocalHost().getHostName();
ServerSocket serverSocket = new ServerSocket(8089);
while (true) {
Socket clientSocket = serverSocket.accept();
PrintWriter out = new PrintWriter(clientSocket.getOutputStream(), true);
BufferedReader in = new BufferedReader(new InputStreamReader(clientSocket.getInputStream()));
String s = in.readLine();
System.out.println(s);
while ("\r\n".equals(in.readLine()));
if ("GET /hostname HTTP/1.1".equals(s)) {
out.println("HTTP/1.1 200 OK");
out.println("Connection: close");
out.println("Content-Type: text/plain");
out.println("Content-Length:" + hostname.length());
out.println();
out.println(hostname);
} else {
out.println("HTTP/1.1 404 Not Found");
out.println("Connection: close");
out.println();
}
out.flush();
}
}
}
The example serves the hostname of the computer.
checkout Simple. its a pretty simple embeddable server with built in support for quite a variety of operations. I particularly love its threading model..
Amazing!
Check out takes. Look at https://github.com/yegor256/takes for quick info
Try this https://github.com/devashish234073/Java-Socket-Http-Server/blob/master/README.md
This API has creates an HTTP server using sockets.
It gets a request from the browser as text
Parses it to retrieve URL info, method, attributes, etc.
Creates dynamic response using the URL mapping defined
Sends the response to the browser.
For example the here's how the constructor in the Response.java class converts a raw response into an http response:
public Response(String resp){
Date date = new Date();
String start = "HTTP/1.1 200 OK\r\n";
String header = "Date: "+date.toString()+"\r\n";
header+= "Content-Type: text/html\r\n";
header+= "Content-length: "+resp.length()+"\r\n";
header+="\r\n";
this.resp=start+header+resp;
}
How about Apache Commons HttpCore project?
From the web site:...
HttpCore Goals
Implementation of the most fundamental HTTP transport aspects
Balance between good performance and the clarity & expressiveness of
API
Small (predictable) memory footprint
Self contained library (no external dependencies beyond JRE)
You can write a pretty simple embedded Jetty Java server.
Embedded Jetty means that the server (Jetty) shipped together with the application as opposed of deploying the application on external Jetty server.
So if in non-embedded approach your webapp built into WAR file which deployed to some external server (Tomcat / Jetty / etc), in embedded Jetty, you write the webapp and instantiate the jetty server in the same code base.
An example for embedded Jetty Java server you can git clone and use: https://github.com/stas-slu/embedded-jetty-java-server-example
The old com.sun.net.httpserver is again a public and accepted API, since Java 11. You can get it as HttpServer class, available as part of jdk.httpserver module. See https://docs.oracle.com/en/java/javase/11/docs/api/jdk.httpserver/com/sun/net/httpserver/HttpServer.html
This class implements a simple HTTP server. A HttpServer is bound to an IP address and port number and listens for incoming TCP connections from clients on this address. The sub-class HttpsServer implements a server which handles HTTPS requests.
So, apart from its limitations, there is no reason to avoid its use anymore.
I use it to publish a control interface in server applications. Reading the User-agent header from a client request I even respond in text/plain to CLI tools like curl or in more elegant HTML way to any other browser.
Cool and easy.
Here is my simple webserver, used in JMeter for testing webhooks (that's why it will close and end itself after request is received).
import java.io.IOException;
import java.io.PrintWriter;
import java.net.ServerSocket;
import java.net.Socket;
public class HttpServer {
private static int extractContentLength(StringBuilder sb) {
int length = 0;
String[] lines = sb.toString().split("\\n");
for (int i = 0; i < lines.length; i++) {
String s = lines[i];
if (s.toLowerCase().startsWith("Content-Length:".toLowerCase()) && i <= lines.length - 2) {
String slength = s.substring(s.indexOf(":") + 1, s.length()).trim();
length = Integer.parseInt(slength);
System.out.println("Length = " + length);
return length;
}
}
return 0;
}
public static void main(String[] args) throws IOException {
int port = Integer.parseInt(args[0]);
System.out.println("starting HTTP Server on port " + port);
StringBuilder outputString = new StringBuilder(1000);
ServerSocket serverSocket = new ServerSocket(port);
serverSocket.setSoTimeout(3 * 60 * 1000); // 3 minutes timeout
while (true) {
outputString.setLength(0); // reset buff
Socket clientSocket = serverSocket.accept(); // blocking
PrintWriter out = new PrintWriter(clientSocket.getOutputStream(), true);
try {
boolean isBodyRead = false;
int dataBuffer;
while ((dataBuffer = clientSocket.getInputStream().read()) != -1) {
if (dataBuffer == 13) { // CR
if (clientSocket.getInputStream().read() == 10) { // LF
outputString.append("\n");
}
} else {
outputString.append((char) dataBuffer);
}
// do we have Content length
int len = extractContentLength(outputString);
if (len > 0) {
int actualLength = len - 1; // we need to substract \r\n
for (int i = 0; i < actualLength; i++) {
int body = clientSocket.getInputStream().read();
outputString.append((char) body);
}
isBodyRead = true;
break;
}
} // end of reading while
if (isBodyRead) {
// response headers
out.println("HTTP/1.1 200 OK");
out.println("Connection: close");
out.println(); // must have empty line for HTTP
out.flush();
out.close(); // close clients connection
}
} catch (IOException ioEx) {
System.out.println(ioEx.getMessage());
}
System.out.println(outputString.toString());
break; // stop server - break while true
} // end of outer while true
serverSocket.close();
} // end of method
}
You can test it like this:
curl -X POST -H "Content-Type: application/json" -H "Connection: close" -d '{"name": "gustinmi", "email": "gustinmi at google dot com "}' -v http://localhost:8081/
I had some fun, I toyed around and pieced together this. I hope it helps you.
You are going to need Gradle installed or use Maven with a plugin.
build.gradle
plugins {
id 'application'
}
group 'foo.bar'
version '1.0'
repositories {
mavenCentral()
}
application{
mainClass.set("foo.FooServer")
}
dependencies {}
FooServer
The main entry point, your main class.
package foo;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.ServerSocket;
import java.net.Socket;
import java.nio.ByteBuffer;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentMap;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
public class FooServer {
public static void main(String[] args) throws IOException {
ServerSocket serverSocket = new ServerSocket(7654);
serverSocket.setPerformancePreferences(0, 1, 2);
/* the higher the numbers, the better the concurrent performance, ha!
we found that a 3:7 ratio to be optimal
3 partitioned executors to 7 network executors */
ExecutorService executors = Executors.newFixedThreadPool(3);
executors.execute(new PartitionedExecutor(serverSocket));
}
public static class PartitionedExecutor implements Runnable {
ServerSocket serverSocket;
public PartitionedExecutor(ServerSocket serverSocket) {
this.serverSocket = serverSocket;
}
#Override
public void run() {
ExecutorService executors = Executors.newFixedThreadPool(30);
executors.execute(new NetworkRequestExecutor(serverSocket, executors));
}
}
public static class NetworkRequestExecutor implements Runnable{
String IGNORE_CHROME = "/favicon.ico";
String BREAK = "\r\n";
String DOUBLEBREAK = "\r\n\r\n";
Integer REQUEST_METHOD = 0;
Integer REQUEST_PATH = 1;
Integer REQUEST_VERSION = 2;
String RENDERER;
Socket socketClient;
ExecutorService executors;
ServerSocket serverSocket;
public NetworkRequestExecutor(ServerSocket serverSocket, ExecutorService executors){
this.serverSocket = serverSocket;
this.executors = executors;
}
#Override
public void run() {
try {
socketClient = serverSocket.accept();
Thread.sleep(19);//do this for safari, its a hack but safari requires something like this.
InputStream requestInputStream = socketClient.getInputStream();
OutputStream clientOutput = socketClient.getOutputStream();
if (requestInputStream.available() == 0) {
requestInputStream.close();
clientOutput.flush();
clientOutput.close();
executors.execute(new NetworkRequestExecutor(serverSocket, executors));
return;
}
ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
ByteBuffer byteBuffer = ByteBuffer.allocate(1024);
int bytesRead;
while ((bytesRead = requestInputStream.read(byteBuffer.array())) != -1) {
byteArrayOutputStream.write(byteBuffer.array(), 0, bytesRead);
if (requestInputStream.available() == 0) break;
}
String completeRequestContent = byteArrayOutputStream.toString();
String[] requestBlocks = completeRequestContent.split(DOUBLEBREAK, 2);
String headerComponent = requestBlocks[0];
String[] methodPathComponentsLookup = headerComponent.split(BREAK);
String methodPathComponent = methodPathComponentsLookup[0];
String[] methodPathVersionComponents = methodPathComponent.split("\\s");
String requestVerb = methodPathVersionComponents[REQUEST_METHOD];
String requestPath = methodPathVersionComponents[REQUEST_PATH];
String requestVersion = methodPathVersionComponents[REQUEST_VERSION];
if (requestPath.equals(IGNORE_CHROME)) {
requestInputStream.close();
clientOutput.flush();
clientOutput.close();
executors.execute(new NetworkRequestExecutor(serverSocket, executors));
return;
}
ConcurrentMap<String, String> headers = new ConcurrentHashMap<>();
String[] headerComponents = headerComponent.split(BREAK);
for (String headerLine : headerComponents) {
String[] headerLineComponents = headerLine.split(":");
if (headerLineComponents.length == 2) {
String fieldKey = headerLineComponents[0].trim();
String content = headerLineComponents[1].trim();
headers.put(fieldKey.toLowerCase(), content);
}
}
clientOutput.write("HTTP/1.1 200 OK".getBytes());
clientOutput.write(BREAK.getBytes());
Integer bytesLength = "hi".length();
String contentLengthBytes = "Content-Length:" + bytesLength;
clientOutput.write(contentLengthBytes.getBytes());
clientOutput.write(BREAK.getBytes());
clientOutput.write("Server: foo server".getBytes());
clientOutput.write(BREAK.getBytes());
clientOutput.write("Content-Type: text/html".getBytes());
clientOutput.write(DOUBLEBREAK.getBytes());
clientOutput.write("hi".getBytes());
clientOutput.close();
socketClient.close();
executors.execute(new NetworkRequestExecutor(serverSocket, executors));
} catch (IOException ex) {
ex.printStackTrace();
} catch (InterruptedException ioException) {
ioException.printStackTrace();
}
}
}
}
Run it:
gradle run
Browse to:
http://localhost:7654/