add rest service in core java application

In this post, we will learn about add rest service in core java application

We are in spring boot world, where exposing a http endpoint is much easier, but when it comes to a standalone java application we will get confused

Java has a feature to expose Http endpoint from a standalone application.
Using import com.sun.net.httpserver.HttpExchange;

In below example, we are exposing an Http endpoint on port number 8080 with endpoint /health

Example

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 HttpServerExample {

	public static void main(String[] args) throws Exception {
		try {
			HttpServer server = HttpServer.create(new InetSocketAddress(8080), 0);
			server.createContext("/health", new Handler());
			server.setExecutor(null);
			server.start();
		} catch (Exception e) {
			e.printStackTrace();
		}

	}

	static class Handler implements HttpHandler {
		@Override
		public void handle(HttpExchange t) throws IOException {
			String response = "Up & Running";
			t.sendResponseHeaders(200, response.length());
			OutputStream os = t.getResponseBody();
			os.write(response.getBytes());
			os.close();
		}
	}
}

Output

http://localhost:8080/health

Up & Running

If you are not found com.net.sun.http package in your eclipse follow this URL https://beginnersbug.com/com-sun-net-httpserver-httpexchange-not-found-in-eclipse

Github

https://github.com/rkumar9090/BeginnersBug/blob/master/BegineersBug/src/com/geeks/example/HttpServerExample.java