揭秘Java高效获取HTTP状态码的实战技巧

在Java中，处理HTTP请求是日常开发中常见的任务。获取HTTP状态码是判断请求成功与否的重要依据。本文将深入探讨Java中高效获取HTTP状态码的实战技巧，包括使用内置库、第三方库以及自定义解决方案。

一、使用Java内置库

Java内置的HttpURLConnection类可以用来发送HTTP请求并获取响应。以下是如何使用它来获取HTTP状态码的示例：

import java.io.BufferedReader; import java.io.InputStreamReader; import java.net.HttpURLConnection; import java.net.URL; public class HttpUrlConnectionExample { public static void main(String[] args) { try { URL url = new URL("http://example.com"); HttpURLConnection connection = (HttpURLConnection) url.openConnection(); connection.setRequestMethod("GET"); int responseCode = connection.getResponseCode(); System.out.println("Response Code : " + responseCode); if (responseCode == HttpURLConnection.HTTP_OK) { BufferedReader in = new BufferedReader(new InputStreamReader(connection.getInputStream())); String inputLine; StringBuffer response = new StringBuffer(); while ((inputLine = in.readLine()) != null) { response.append(inputLine); } in.close(); System.out.println(response.toString()); } else { System.out.println("GET request not worked"); } } catch (Exception e) { e.printStackTrace(); } } }

二、使用第三方库

除了Java内置库，还有许多第三方库可以帮助我们更高效地处理HTTP请求，如Apache HttpClient和OkHttp。以下是如何使用Apache HttpClient获取HTTP状态码的示例：

import org.apache.http.HttpEntity; import org.apache.http.client.methods.CloseableHttpResponse; import org.apache.http.client.methods.HttpGet; import org.apache.http.impl.client.CloseableHttpClient; import org.apache.http.impl.client.HttpClients; import org.apache.http.util.EntityUtils; public class ApacheHttpClientExample { public static void main(String[] args) { try (CloseableHttpClient httpClient = HttpClients.createDefault()) { HttpGet httpGet = new HttpGet("http://example.com"); CloseableHttpResponse response = httpClient.execute(httpGet); int statusCode = response.getStatusLine().getStatusCode(); System.out.println("Response Code : " + statusCode); HttpEntity entity = response.getEntity(); if (entity != null) { String result = EntityUtils.toString(entity); System.out.println(result); } response.close(); } catch (Exception e) { e.printStackTrace(); } } }

三、自定义解决方案

对于一些特定的需求，可能需要自定义解决方案来获取HTTP状态码。例如，使用Java的JSoup库解析HTML页面并获取状态码：

import org.jsoup.Jsoup; import org.jsoup.nodes.Document; public class JsoupExample { public static void main(String[] args) { try { Document document = Jsoup.connect("http://example.com").get(); System.out.println("Response Code : " + document.statusCode()); } catch (Exception e) { e.printStackTrace(); } } }