Question

I’m trying to build a simple HTTP Server using Java, using

java.net.ServerSocket = new ServerSocket(this.port, 0, this.ip);
java.net.Socket connection = null;
connection = server.accept();
java.io.OutputStream out = new BufferedOutputStream(connection.getOutputStream());

when connected using web browser, i’m simply write the output (HTTP headers + html code) from a string

String headers = "http headers";
String response = "this is the response";
out.write(headers.getBytes());
out.write(response.getBytes());
out.flush();
connection.close();

and the browser display it correctly.

And now my problem is, i want to construct a full webpage (html, javascript, css, images) and put those files into the Java package (JAR) file, and of course, those files are designed not-to-be modified after the JAR is ready to use. And here’s the questions:

1. how to achieve this? storing the files inside the JAR and then output them when a connection is made.

2. how output images file (non-text) just like output-ing String by out.write() ?

Thanks, any sample or code is appreciated.

Answer 1

Is implementing an HTTP server your primary problem or just a way to achieve some other goal? If the latter, consider embedding Tomcat or Jetty, much simpler and with standard servlet API.

Back to your question: JAR is just a ZIP file, you can put anything there, including files, images, movies, etc. If you place a file inside a JAR file you can load it easily with:

InputStream is = getClass().getResourceAsStream("/dir/file.png");

See these questions for details how getResourceAsStream() works:

• Junit + getResourceAsStream Returning Null
• getResourceAsStream() vs FileInputStream
• how do you make getResourceAsStream work while debugging Java in Eclipse?
• Different ways of loading a file as an InputStream
• getResourceAsStream() is always returning null

About your second question: when you have an InputStream instance you can just read it byte-by-byte and copy to target out OutputStream. Of course there are better, safer and faster ways, but that’s beyond the scope of this question. Just have a look at IOUtils.copy():

IOUtils.copy(is, out);

And the last hint concerning your code: if you are sending Strings , consider OutputStreamWriter and PrintWriter which have easier API.