Note The BufferedReader reads characters; while the InputStream is a stream of bytes. The BufferedReader can’t read the InputStream directly; So, we need to use an adapter like InputStreamReader to convert bytes to characters format. For example: // BufferedReader -> InputStreamReader -> InputStream BufferedReader br = new BufferedReader( new InputStreamReader(inputStream, StandardCharsets.UTF_8)); 1. Reads a file […]
This article shows you how to use Apache HttpClient to perform an HTTP basic authentication. P.S Tested with HttpClient 4.5.10 pom.xml <dependency> <groupId>org.apache.httpcomponents</groupId> <artifactId>httpclient</artifactId> <version>4.5.10</version> </dependency> Start a simple Spring Security WebApp providing HTTP basic authentication, and test it with the HttpClient 1. Basic Authentication The key is to configure CredentialsProvider and pass it to […]
Eclipse IDE prompts warning on new DefaultHttpClient, mark this class as deprecated. package com.mkyong.web.controller; import org.apache.http.Header; import org.apache.http.HttpResponse; import org.apache.http.client.HttpClient; import org.apache.http.client.methods.HttpGet; import org.apache.http.impl.client.DefaultHttpClient; public class WebCrawler { public static void main(String[] args) throws Exception { HttpClient client = new DefaultHttpClient(); HttpGet request = new HttpGet("https://mkyong.com"); HttpResponse response = client.execute(request); //… } } Solution Dive […]
In this article, we will show you a few examples to make HTTP GET/POST requests via the following APIs Apache HttpClient 4.5.10 OkHttp 4.2.2 Java 11 HttpClient Java 1.1 HttpURLConnection (Not recommend) 1. Apache HttpClient In the old days, this Apache HttpClient is the de facto standard to send an HTTP GET/POST request in Java. […]
This article shows you how to use Apache HttpClient to send an HTTP GET/POST requests, JSON, authentication, timeout, redirection and some frequent used examples. P.S Tested with HttpClient 4.5.10 pom.xml <dependency> <groupId>org.apache.httpcomponents</groupId> <artifactId>httpclient</artifactId> <version>4.5.10</version> </dependency> 1. Send GET Request 1.1 Close manually. HttpClientExample1_1.java package com.mkyong.http; import org.apache.http.HttpEntity; import org.apache.http.HttpHeaders; import org.apache.http.client.methods.CloseableHttpResponse; import org.apache.http.client.methods.HttpGet; import org.apache.http.impl.client.CloseableHttpClient; […]
This example shows you how to get the Http response header values in Java. 1. Standard JDK example. URL obj = new URL("https://mkyong.com"); URLConnection conn = obj.openConnection(); //get all headers Map<String, List<String>> map = conn.getHeaderFields(); for (Map.Entry<String, List<String>> entry : map.entrySet()) { System.out.println("Key : " + entry.getKey() + " ,Value : " + entry.getValue()); } […]
Apache HttpClient is a robust and complete solution Java library to perform HTTP operations, including RESTful service. In this tutorial, we show you how to create a RESTful Java client with Apache HttpClient, to perform a “GET” and “POST” request. Note The RESTful services from last “Jackson + JAX-RS” article will be reused. 1. Get […]
