CloseableHttpClient httpClient = HttpClients.createDefault();

CloseableHttpClient httpClient = HttpClients.createSystem();

 CloseableHttpClient httpClient = HttpClients.custom()
     .setMaxConnTotal(100) // 最大連接數(shù)
     .setMaxConnPerRoute(10) // 每個(gè)路由的最大連接數(shù)
     .build();

 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;
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 public class HttpClientExample {
     public static void main(String[] args) {
         // 1. 創(chuàng)建 HTTP 客戶端
         try (CloseableHttpClient httpClient = HttpClients.createDefault()) {
             // 2. 創(chuàng)建 HTTP GET 請(qǐng)求
             HttpGet request = new HttpGet("https://jsonplaceholder.typicode.com/posts/1");
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             // 3. 發(fā)送請(qǐng)求并獲取響應(yīng)
             try (CloseableHttpResponse response = httpClient.execute(request)) {
                 // 4. 檢查響應(yīng)狀態(tài)碼
                 int statusCode = response.getStatusLine().getStatusCode();
                 System.out.println("Status Code: " + statusCode);
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                 // 5. 獲取響應(yīng)內(nèi)容
                 String responseBody = EntityUtils.toString(response.getEntity());
                 System.out.println("Response Body: " + responseBody);
             }
         } catch (Exception e) {
             e.printStackTrace();
         }
     }
 }

 CloseableHttpClient httpClient = HttpClients.custom()
     .setMaxConnTotal(100) // 最大連接數(shù)
     .setMaxConnPerRoute(10) // 每個(gè)路由的最大連接數(shù)
     .build();

 RequestConfig requestConfig = RequestConfig.custom()
     .setConnectTimeout(5000) // 連接超時(shí)時(shí)間
     .setSocketTimeout(5000) // 讀取超時(shí)時(shí)間
     .build();
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 CloseableHttpClient httpClient = HttpClients.custom()
     .setDefaultRequestConfig(requestConfig)
     .build();

 HttpHost proxy = new HttpHost("proxy.example.com", 8080);
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 CloseableHttpClient httpClient = HttpClients.custom()
     .setProxy(proxy)
     .build();

 SSLContext sslContext = SSLContexts.custom()
     .loadTrustMaterial((chain, authType) -> true) // 信任所有證書
     .build();
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 CloseableHttpClient httpClient = HttpClients.custom()
     .setSSLContext(sslContext)
     .build();

CloseableHttpClient httpClient = HttpClients.createDefault();

 CloseableHttpClient httpClient = HttpClients.custom()
     .setConnectionManager(connectionManager)  // 連接池管理
     .setDefaultRequestConfig(requestConfig)   // 請(qǐng)求超時(shí)配置
     .setRetryHandler(retryHandler)            // 請(qǐng)求重試策略
     .setProxy(proxy)                          // 代理設(shè)置
     .setSSLContext(sslContext)                // SSL/TLS 配置
     .build();

 PoolingHttpClientConnectionManager connectionManager = 
     new PoolingHttpClientConnectionManager();
 connectionManager.setMaxTotal(200);          // 最大總連接數(shù)
 connectionManager.setDefaultMaxPerRoute(20); // 每個(gè)路由（目標(biāo)主機(jī)）的最大連接數(shù)
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 CloseableHttpClient httpClient = HttpClients.custom()
     .setConnectionManager(connectionManager)
     .build();

 RequestConfig requestConfig = RequestConfig.custom()
     .setConnectTimeout(5000)    // 連接建立超時(shí)時(shí)間（毫秒）
     .setSocketTimeout(10000)     // 數(shù)據(jù)傳輸超時(shí)時(shí)間（毫秒）
     .setConnectionRequestTimeout(2000) // 從連接池獲取連接的超時(shí)時(shí)間
     .build();
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 CloseableHttpClient httpClient = HttpClients.custom()
     .setDefaultRequestConfig(requestConfig)
     .build();

 HttpRequestRetryHandler retryHandler = (exception, executionCount, context) -> {
     if (executionCount >= 3) return false; // 最大重試次數(shù)
     if (exception instanceof NoHttpResponseException) return true; // 無(wú)響應(yīng)時(shí)重試
     return false;
 };
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 CloseableHttpClient httpClient = HttpClients.custom()
     .setRetryHandler(retryHandler)
     .build();

 HttpHost proxy = new HttpHost("proxy.example.com", 8080);
 CloseableHttpClient httpClient = HttpClients.custom()
     .setProxy(proxy)
     .build();

 SSLContext sslContext = SSLContexts.custom()
     .loadTrustMaterial((chain, authType) -> true) // 信任所有證書
     .build();
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 CloseableHttpClient httpClient = HttpClients.custom()
     .setSSLContext(sslContext)
     .setSSLHostnameVerifier(NoopHostnameVerifier.INSTANCE) // 跳過(guò)主機(jī)名驗(yàn)證
     .build();

 CredentialsProvider credentialsProvider = new BasicCredentialsProvider();
 credentialsProvider.setCredentials(
     new AuthScope("host.example.com", 80),
     new UsernamePasswordCredentials("user", "pass")
 );
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 CloseableHttpClient httpClient = HttpClients.custom()
     .setDefaultCredentialsProvider(credentialsProvider)
     .build();

 HttpGet httpGet = new HttpGet("https://api.example.com/data");
 try (CloseableHttpResponse response = httpClient.execute(httpGet)) {
     int statusCode = response.getStatusLine().getStatusCode();
     HttpEntity entity = response.getEntity();
     String content = EntityUtils.toString(entity);
     EntityUtils.consume(entity); // 確保資源釋放
 }

 HttpPost httpPost = new HttpPost("https://api.example.com/create");
 StringEntity jsonEntity = new StringEntity("{\"key\":\"value\"}", ContentType.APPLICATION_JSON);
 httpPost.setEntity(jsonEntity);
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 try (CloseableHttpResponse response = httpClient.execute(httpPost)) {
     // 處理響應(yīng)...
 }

 HttpPost httpPost = new HttpPost("https://api.example.com/upload");
 FileBody fileBody = new FileBody(new File("path/to/file"));
 MultipartEntityBuilder builder = MultipartEntityBuilder.create()
     .addPart("file", fileBody)
     .addTextBody("comment", "File upload");
 httpPost.setEntity(builder.build());

 CloseableHttpAsyncClient asyncClient = HttpAsyncClients.custom().build();
 asyncClient.start();
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 SimpleHttpRequest request = SimpleHttpRequest.get("https://api.example.com/data");
 Future<SimpleHttpResponse> future = asyncClient.execute(request, new FutureCallback<>() {
     @Override
     public void completed(SimpleHttpResponse response) {
         System.out.println("Response: " + response.getBodyText());
     }
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     @Override
     public void failed(Exception ex) {
         ex.printStackTrace();
     }
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     @Override
     public void cancelled() {
         System.out.println("Request cancelled");
     }
 });

 CloseableHttpClient httpClient = HttpClients.custom()
     .addInterceptorFirst((HttpRequestInterceptor) (request, context) -> {
         request.addHeader("X-Custom-Header", "value");
         System.out.println("Request URI: " + request.getRequestLine().getUri());
     })
     .build();

 CookieStore cookieStore = new BasicCookieStore();
 CloseableHttpClient httpClient = HttpClients.custom()
     .setDefaultCookieStore(cookieStore)
     .build();

 try (CloseableHttpClient httpClient = HttpClients.createDefault()) {
     try (CloseableHttpResponse response = httpClient.execute(request)) {
         // 處理響應(yīng)...
     }
 }