HTTP protocol analysis and structure in Apache httpcore
Apache HTTPCORE provides the function of HTTP protocol analysis and construction.In network communication, the HTTP protocol is responsible for the communication between the client and the server, and the HTTPCORE provides a convenient method to handle the HTTP protocol.
HTTP protocol analysis is a key feature of HTTPCORE.When the server receives the HTTP request sent by the client, it needs to be able to analyze the request to understand the client request method, URI, and head information.Httpcore provides a HTTPREQUESTPARSER class to resolve the HTTP request.The following is a simple example that shows how to use HTTPREQUESTPARSER to resolve an HTTP request:
import org.apache.http.HttpRequest;
import org.apache.http.HttpRequestInterceptor;
import org.apache.http.HttpVersion;
import org.apache.http.ProtocolException;
import org.apache.http.RequestLine;
import org.apache.http.entity.ContentType;
import org.apache.http.impl.DefaultHttpServerConnection;
import org.apache.http.message.BasicHttpRequest;
import org.apache.http.protocol.HttpContext;
import org.apache.http.protocol.HttpCoreContext;
import org.apache.http.protocol.HttpProcessor;
import org.apache.http.protocol.HttpRequestHandler;
import org.apache.http.protocol.HttpRequestHandlerMapper;
import org.apache.http.protocol.HttpRequestInterceptorList;
import org.apache.http.protocol.HttpRequestParser;
import org.apache.http.protocol.ImmutableHttpProcessor;
import org.apache.http.protocol.RequestConnControl;
import org.apache.http.protocol.RequestExpectContinue;
import org.apache.http.protocol.RequestTargetHost;
import org.apache.http.protocol.RequestUserAgent;
import org.apache.http.util.Args;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.ServerSocket;
import java.net.Socket;
public class HttpParserExample {
public static void main(String[] args) throws Exception {
ServerSocket serverSocket = new ServerSocket(8080);
while (true) {
Socket socket = serverSocket.accept();
DefaultHttpServerConnection serverConnection = new DefaultHttpServerConnection();
serverConnection.bind(socket);
HttpRequestParser requestParser = new HttpRequestParser();
HttpRequest request = requestParser.parse(serverConnection.receiveRequestHeader());
// You can obtain the request information from the Request object, such as the request method, URI, head information, etc.
RequestLine requestLine = request.getRequestLine();
System.out.println ("Request method:" + Requestline.getMethod ());
System.out.println("URI: " + requestLine.getUri());
// Treatment according to needs
serverConnection.flush();
serverConnection.close();
}
}
}
In addition to HTTP protocol analysis, HTTPCORE also provides the function of HTTP protocol construction.In some scenarios, the client needs to send a request to the server through the HTTP protocol.Httpcore provides a HTTP request for HTTPREQUESTBUILDER class.The following is an example that shows how to use httprequestbuilder to build a HTTP GET request and send it to the server:
import org.apache.http.HttpEntityEnclosingRequest;
import org.apache.http.HttpHost;
import org.apache.http.HttpRequest;
import org.apache.http.HttpResponse;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.methods.HttpUriRequest;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.util.EntityUtils;
public class HttpClientExample {
public static void main(String[] args) throws Exception {
CloseableHttpClient httpClient = HttpClients.createDefault();
HttpHost target = new HttpHost("www.example.com", 80, "http");
HttpGet request = new HttpGet("/");
HttpResponse response = httpClient.execute(target, request);
System.out.println ("Response status code:" + response.getstatusline (). GetStatusCode ());
String responseBody = EntityUtils.toString(response.getEntity());
System.out.println ("Response:" + Responsebody);
httpClient.close();
}
}
In the above example code, a CloseablehttpClient object is first created.Then, by constructing an HTTPGET object to represent a HTTP GET request and specify the target host and path of the request.Finally, use the HTTPClient object to execute this request and obtain the server's response.You can obtain information such as the response status code and response body from the response object.
In summary, Apache HTTPCORE provides convenient APIs to process the analysis and construction of the HTTP protocol.Using HTTPCORE can easily analyze and build HTTP requests and responses, providing powerful functions for network communication.
