Entering the technical inside of the HTTPClient framework in the Java class library (Inside the Technical Secrets of the HTTPClient Framework in Java Class Libraries)
Entering the technical inside story of the HTTPClient framework in the Java library
Introduction:
HTTPClient is an important framework for sending HTTP requests and processing HTTP response in the Java class library.It provides a simple and easy -to -use method to communicate with the web server, and supports multiple protocols, certification, connection management and request/response treatment.
Start of the httpclient framework:
In order to use the HTTPClient framework, we need to import the HTTPClient class library in the Java project.You can introduce the latest version of HTTPClient in the Maven project through the following methods:
<dependency>
<groupId>org.apache.httpcomponents</groupId>
<artifactId>httpclient</artifactId>
<version>4.5.13</version>
</dependency>
Basic usage:
The following example shows how to use httpclient to send a simple GET request and process the response:
import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.HttpClientBuilder;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
public class HttpClientExample {
public static void main(String[] args) {
HttpClient httpClient = HttpClientBuilder.create().build();
// Create HTTPGET request
HttpGet request = new HttpGet("http://www.example.com");
try {
// Send a request and get a response
HttpResponse response = httpClient.execute(request);
// Read the response content
BufferedReader reader = new BufferedReader(new InputStreamReader(response.getEntity().getContent()));
String line;
StringBuffer result = new StringBuffer();
while ((line = reader.readLine()) != null) {
result.append(line);
}
// Print the Response results
System.out.println(result.toString());
} catch (IOException e) {
e.printStackTrace();
}
}
}
Connection management:
The HTTPClient framework provides flexible and configurable connection management functions, including the maximum number of connection, connection timeout time, connection reuse, etc.The following example shows how to use the connection manager to create an HTTPClient instance:
import org.apache.http.HttpClientConnectionManager;
import org.apache.http.client.HttpClient;
import org.apache.http.impl.client.HttpClientBuilder;
import org.apache.http.impl.conn.PoolingHttpClientConnectionManager;
public class HttpClientConnectionManagerExample {
public static void main(String[] args) {
// Create a connection manager
HttpClientConnectionManager connectionManager = new PoolingHttpClientConnectionManager();
// Configure the maximum number of connections
((PoolingHttpClientConnectionManager) connectionManager).setMaxTotal(100);
// Configure the maximum number of connections for each route
((PoolingHttpClientConnectionManager) connectionManager).setDefaultMaxPerRoute(10);
// Create HTTPCLIENT instance
HttpClient httpClient = HttpClientBuilder.create().setConnectionManager(connectionManager).build();
// Use httpclient to send requests ...
}
}
Request and response processing:
HTTPClient framework supports various request methods (get, post, put, delete, etc.) and settings of the request header.We can send different types of requests by setting the parameters of request objects such as HTTPGET, HTTPPOST, etc.Similarly, we can get the response status code, response head, and response entity from the HTTPRESPONSE object.
Certification:
The HTTPClient framework supports various certification mechanisms, such as basic certification, abstract certification, and client certification certification.We can provide authentication credentials by setting the CredentialSProvider or AuthCache objects in the HTTPCLIENT instance to provide authentication credentials and send it with the request.
Summarize:
By in -depth research on the technical inside story of the HTTPClient framework, we understand how to use the HTTPClient framework in the Java class library to send HTTP requests and process HTTP responses.We have also learned how to use functions such as connection management, request and response processing, and certification to meet different needs.This powerful framework provides us with the flexibility and convenience of communicating with the web server.
