{"id":773,"date":"2013-10-09T19:19:43","date_gmt":"2013-10-09T11:19:43","guid":{"rendered":"http:\/\/www.yeetrack.com\/?p=773"},"modified":"2013-10-09T21:49:37","modified_gmt":"2013-10-09T13:49:37","slug":"httpclient-4-3%e6%95%99%e7%a8%8b-%e7%ac%ac%e4%b8%80%e7%ab%a0-%e5%9f%ba%e6%9c%ac%e6%a6%82%e5%bf%b5","status":"publish","type":"post","link":"https:\/\/www.yeetrack.com\/?p=773","title":{"rendered":"HttpClient 4.3\u6559\u7a0b \u7b2c\u4e00\u7ae0 \u57fa\u672c\u6982\u5ff5"},"content":{"rendered":"<p><meta http-equiv=\"content-type\" content=\"text\/html; charset=utf-8\" \/><br \/>\n<a name=\"Request-execution\"><\/a><\/p>\n<h2>1.1. \u8bf7\u6c42\u6267\u884c<\/h2>\n<p>HttpClient\u6700\u57fa\u672c\u7684\u529f\u80fd\u5c31\u662f\u6267\u884cHttp\u65b9\u6cd5\u3002\u4e00\u4e2aHttp\u65b9\u6cd5\u7684\u6267\u884c\u6d89\u53ca\u5230\u4e00\u4e2a\u6216\u8005\u591a\u4e2aHttp\u8bf7\u6c42\/Http\u54cd\u5e94\u7684\u4ea4\u4e92\uff0c\u901a\u5e38\u8fd9\u4e2a\u8fc7\u7a0b\u90fd\u4f1a\u81ea\u52a8\u88abHttpClient\u5904\u7406\uff0c\u5bf9\u7528\u6237\u900f\u660e\u3002\u7528\u6237\u53ea\u9700\u8981\u63d0\u4f9bHttp\u8bf7\u6c42\u5bf9\u8c61\uff0cHttpClient\u5c31\u4f1a\u5c06http\u8bf7\u6c42\u53d1\u9001\u7ed9\u76ee\u6807\u670d\u52a1\u5668\uff0c\u5e76\u4e14\u63a5\u6536\u670d\u52a1\u5668\u7684\u54cd\u5e94\uff0c\u5982\u679chttp\u8bf7\u6c42\u6267\u884c\u4e0d\u6210\u529f\uff0chttpclient\u5c31\u4f1a\u629b\u51fa\u5f02\u6837\u3002<\/p>\n<p>\u4e0b\u9762\u662f\u4e2a\u5f88\u7b80\u5355\u7684http\u8bf7\u6c42\u6267\u884c\u7684\u4f8b\u5b50\uff1a<\/p>\n<pre><code>    CloseableHttpClient httpclient = HttpClients.createDefault();\n    HttpGet httpget = new HttpGet(\"https:\/\/www.yeetrack.com\/\");\n    CloseableHttpResponse response = httpclient.execute(httpget);<!--more-->\n    try {\n        &lt;...&gt;\n    } finally {\n        response.close();\n    }\n<\/code><\/pre>\n<p><a name=\"HTTP-request\"><\/a><\/p>\n<h3>1.1.1. Http\u8bf7\u6c42<\/h3>\n<p>\u6240\u6709\u7684Http\u8bf7\u6c42\u90fd\u6709\u4e00\u4e2a\u8bf7\u6c42\u5217\uff08request line\uff09\uff0c\u5305\u62ec\u65b9\u6cd5\u540d\u3001\u8bf7\u6c42\u7684URI\u548cHttp\u7248\u672c\u53f7\u3002<\/p>\n<p>HttpClient\u652f\u6301HTTP\/1.1\u8fd9\u4e2a\u7248\u672c\u5b9a\u4e49\u7684\u6240\u6709Http\u65b9\u6cd5\uff1a<code>GET<\/code>,<code>HEAD<\/code>,<code>POST<\/code>,<code>PUT<\/code>,<code>DELETE<\/code>,'TRACE<code>\u548c<\/code>OPTIONS<code>\u3002\u5bf9\u4e8e\u6bcf\u4e00\u79cdhttp\u65b9\u6cd5\uff0cHttpClient\u90fd\u5b9a\u4e49\u4e86\u4e00\u4e2a\u76f8\u5e94\u7684\u7c7b\uff1a<\/code>HttpGet<code>,<\/code>HttpHead<code>,<\/code>HttpPost<code>,<\/code>HttpPut<code>,<\/code>HttpDelete<code>,<\/code>HttpTrace<code>\u548c<\/code>HttpOpquertions`\u3002<\/p>\n<p>Request-URI\u5373\u7edf\u4e00\u8d44\u6e90\u5b9a\u4f4d\u7b26\uff0c\u7528\u6765\u6807\u660eHttp\u8bf7\u6c42\u4e2d\u7684\u8d44\u6e90\u3002Http request URIS\u5305\u542b\u534f\u8bae\u540d\u3001\u4e3b\u673a\u540d\u3001\u4e3b\u673a\u7aef\u53e3\uff08\u53ef\u9009\uff09\u3001\u8d44\u6e90\u8def\u5f84\u3001query\uff08\u53ef\u9009\uff09\u548c\u7247\u6bb5\u4fe1\u606f\uff08\u53ef\u9009\uff09\u3002<\/p>\n<pre><code>    HttpGet httpget = new HttpGet(\n \"http:\/\/www.google.com\/search?hl=en&amp;q=httpclient&amp;btnG=Google+Search&amp;aq=f&amp;oq=\");\n<\/code><\/pre>\n<p>HttpClient\u63d0\u4f9b<code>URIBuilder<\/code>\u5de5\u5177\u7c7b\u6765\u7b80\u5316URIs\u7684\u521b\u5efa\u548c\u4fee\u6539\u8fc7\u7a0b\u3002<\/p>\n<pre><code>    URI uri = new URIBuilder()\n    .setScheme(\"http\")\n    .setHost(\"www.google.com\")\n    .setPath(\"\/search\")\n    .setParameter(\"q\", \"httpclient\")\n    .setParameter(\"btnG\", \"Google Search\")\n    .setParameter(\"aq\", \"f\")\n    .setParameter(\"oq\", \"\")\n    .build();\n    HttpGet httpget = new HttpGet(uri);\n    System.out.println(httpget.getURI());\n<\/code><\/pre>\n<p>\u4e0a\u8ff0\u4ee3\u7801\u4f1a\u5728\u63a7\u5236\u53f0\u8f93\u51fa\uff1a<\/p>\n<p>http:\/\/www.google.com\/search?q=httpclient&btnG=Google+Search&aq=f&oq=<br \/>\n<a name=\"HTTP-response\"><\/a><\/p>\n<h3>1.1.2. HTTP\u54cd\u5e94<\/h3>\n<p>\u670d\u52a1\u5668\u6536\u5230\u5ba2\u6237\u7aef\u7684http\u8bf7\u6c42\u540e\uff0c\u5c31\u4f1a\u5bf9\u5176\u8fdb\u884c\u89e3\u6790\uff0c\u7136\u540e\u628a\u54cd\u5e94\u53d1\u7ed9\u5ba2\u6237\u7aef\uff0c\u8fd9\u4e2a\u54cd\u5e94\u5c31\u662fHTTP response.HTTP\u54cd\u5e94\u7b2c\u4e00\u884c\u662fHTTP\u7248\u672c\u53f7\uff0c\u7136\u540e\u662f\u54cd\u5e94\u72b6\u6001\u7801\u548c\u54cd\u5e94\u5185\u5bb9\u3002<\/p>\n<pre><code>    HttpResponse response = new BasicHttpResponse(HttpVersion.HTTP_1_1, HttpStatus.SC_OK, \"OK\");\n\n    System.out.println(response.getProtocolVersion());\n    System.out.println(response.getStatusLine().getStatusCode());\n    System.out.println(response.getStatusLine().getReasonPhrase());\n    System.out.println(response.getStatusLine().toString());\n<\/code><\/pre>\n<p>\u4e0a\u8ff0\u4ee3\u7801\u4f1a\u5728\u63a7\u5236\u53f0\u8f93\u51fa\uff1a<\/p>\n<pre><code>    HTTP\/1.1\n    200\n    OK\n    HTTP\/1.1 200 OK\n<\/code><\/pre>\n<p><a name=\"Working-with-message-headers\"><\/a><\/p>\n<h3>1.1.3. \u6d88\u606f\u5934<\/h3>\n<p>\u4e00\u4e2aHttp\u6d88\u606f\u53ef\u4ee5\u5305\u542b\u4e00\u7cfb\u5217\u7684\u6d88\u606f\u5934\uff0c\u7528\u6765\u5bf9http\u6d88\u606f\u8fdb\u884c\u63cf\u8ff0\uff0c\u6bd4\u5982\u6d88\u606f\u957f\u5ea6\uff0c\u6d88\u606f\u7c7b\u578b\u7b49\u7b49\u3002HttpClient\u63d0\u4f9b\u4e86API\u6765\u83b7\u53d6\u3001\u6dfb\u52a0\u3001\u4fee\u6539\u3001\u904d\u5386\u6d88\u606f\u5934\u3002<\/p>\n<pre><code>    HttpResponse response = new BasicHttpResponse(HttpVersion.HTTP_1_1, HttpStatus.SC_OK, \"OK\");\n    response.addHeader(\"Set-Cookie\", \"c1=a; path=\/; domain=yeetrack.com\");\n    response.addHeader(\"Set-Cookie\", \"c2=b; path=\\\"\/\\\", c3=c; domain=\\\"yeetrack.com\\\"\");\n    Header h1 = response.getFirstHeader(\"Set-Cookie\");\n    System.out.println(h1);\n    Header h2 = response.getLastHeader(\"Set-Cookie\");\n    System.out.println(h2);\n    Header[] hs = response.getHeaders(\"Set-Cookie\");\n    System.out.println(hs.length);\n<\/code><\/pre>\n<p>\u4e0a\u8ff0\u4ee3\u7801\u4f1a\u5728\u63a7\u5236\u53f0\u8f93\u51fa\uff1a<\/p>\n<pre><code>    Set-Cookie: c1=a; path=\/; domain=yeetrack.com\n    Set-Cookie: c2=b; path=\"\/\", c3=c; domain=\"yeetrack.com\"\n    2\n<\/code><\/pre>\n<p>\u6700\u6709\u6548\u7684\u83b7\u53d6\u6307\u5b9a\u7c7b\u578b\u7684\u6d88\u606f\u5934\u7684\u65b9\u6cd5\u8fd8\u662f\u4f7f\u7528<code>HeaderIterator<\/code>\u63a5\u53e3\u3002<\/p>\n<pre><code>    HttpResponse response = new BasicHttpResponse(HttpVersion.HTTP_1_1, HttpStatus.SC_OK, \"OK\");\n    response.addHeader(\"Set-Cookie\", \"c1=a; path=\/; domain=yeetrack.com\");\n    response.addHeader(\"Set-Cookie\", \"c2=b; path=\\\"\/\\\", c3=c; domain=\\\"<\/code>\n<code>yeetrack.com<\/code>\n<code>\\\"\"); HeaderIterator it = response.headerIterator(\"Set-Cookie\"); while (it.hasNext()) { System.out.println(it.next()); } <\/code><\/pre>\n<p>\u4e0a\u8ff0\u4ee3\u7801\u4f1a\u5728\u63a7\u5236\u53f0\u8f93\u51fa\uff1a<\/p>\n<pre><code>    Set-Cookie: c1=a; path=\/; domain=yeetrack.com\n    Set-Cookie: c2=b; path=\"\/\", c3=c; domain=\"yeetrack.com\"\n<\/code><\/pre>\n<p>HeaderIterator\u4e5f\u63d0\u4f9b\u975e\u5e38\u4fbf\u6377\u7684\u65b9\u5f0f\uff0c\u5c06Http\u6d88\u606f\u89e3\u6790\u6210\u5355\u72ec\u7684\u6d88\u606f\u5934\u5143\u7d20\u3002<\/p>\n<pre><code>    HttpResponse response = new BasicHttpResponse(HttpVersion.HTTP_1_1, HttpStatus.SC_OK, \"OK\");\n    response.addHeader(\"Set-Cookie\", \"c1=a; path=\/; domain=yeetrack.com\");\n    response.addHeader(\"Set-Cookie\", \"c2=b; path=\\\"\/\\\", c3=c; domain=\\\"yeetrack.com\\\"\");\n\n    HeaderElementIterator it = new BasicHeaderElementIterator(response.headerIterator(\"Set-Cookie\"));\n\n    while (it.hasNext()) {\n        HeaderElement elem = it.nextElement(); \n        System.out.println(elem.getName() + \" = \" + elem.getValue());\n        NameValuePair[] params = elem.getParameters();\n        for (int i = 0; i &lt; params.length; i++) {\n            System.out.println(\" \" + params[i]);\n        }\n    }\n<\/code><\/pre>\n<p>\u4e0a\u8ff0\u4ee3\u7801\u4f1a\u5728\u63a7\u5236\u53f0\u8f93\u51fa\uff1a<\/p>\n<pre><code>    c1 = a\n    path=\/\n    domain=yeetrack.com\n    c2 = b\n    path=\/\n    c3 = c\n    domain=yeetrack.com\n<\/code><\/pre>\n<p><a name=\"HTTP-entity\"><\/a><\/p>\n<h3>1.1.4. Http\u5b9e\u4f53<\/h3>\n<p>Http\u6d88\u606f\u53ef\u4ee5\u643a\u5e26http\u5b9e\u4f53\uff0c\u8fd9\u4e2ahttp\u5b9e\u4f53\u65e2\u53ef\u4ee5\u662fhttp\u8bf7\u6c42\uff0c\u4e5f\u53ef\u4ee5\u662fhttp\u54cd\u5e94\u7684\u3002Http\u5b9e\u4f53\uff0c\u53ef\u4ee5\u5728\u67d0\u4e9bhttp\u8bf7\u6c42\u6216\u8005\u54cd\u5e94\u4e2d\u53d1\u73b0\uff0c\u4f46\u4e0d\u662f\u5fc5\u987b\u7684\u3002Http\u89c4\u8303\u4e2d\u5b9a\u4e49\u4e86\u4e24\u79cd\u5305\u542b\u8bf7\u6c42\u7684\u65b9\u6cd5\uff1aPOST\u548cPUT\u3002HTTP\u54cd\u5e94\u4e00\u822c\u4f1a\u5305\u542b\u4e00\u4e2a\u5185\u5bb9\u5b9e\u4f53\u3002\u5f53\u7136\u8fd9\u6761\u89c4\u5219\u4e5f\u6709\u5f02\u5e38\u60c5\u51b5\uff0c\u5982Head\u65b9\u6cd5\u7684\u54cd\u5e94\uff0c204\u6ca1\u6709\u5185\u5bb9\uff0c304\u6ca1\u6709\u4fee\u6539\u6216\u8005205\u5185\u5bb9\u8d44\u6e90\u91cd\u7f6e\u3002<\/p>\n<p>HttpClient\u6839\u636e\u6765\u6e90\u7684\u4e0d\u540c\uff0c\u5212\u5206\u4e86\u4e09\u79cd\u4e0d\u540c\u7684Http\u5b9e\u4f53\u5185\u5bb9\u3002<\/p>\n<ul>\n<li><strong>streamed:<\/strong> Http\u5185\u5bb9\u662f\u901a\u8fc7\u6d41\u6765\u63a5\u53d7\u6216\u8005generated on the fly\u3002\u7279\u522b\u662f\uff0cstreamed\u8fd9\u4e00\u7c7b\u5305\u542b\u4ecehttp\u54cd\u5e94\u4e2d\u83b7\u53d6\u7684\u5b9e\u4f53\u5185\u5bb9\u3002\u4e00\u822c\u8bf4\u6765\uff0cstreamed\u5b9e\u4f53\u662f\u4e0d\u53ef\u91cd\u590d\u7684\u3002<\/li>\n<li><strong>self-contained:<\/strong> The content is in memory or obtained by means that are independent from a connection or other entity\u3002self-contained\u7c7b\u578b\u7684\u5b9e\u4f53\u5185\u5bb9\u901a\u5e38\u662f\u53ef\u91cd\u590d\u7684\u3002\u8fd9\u79cd\u7c7b\u578b\u7684\u5b9e\u4f53\u901a\u5e38\u7528\u4e8e\u5173\u95edhttp\u8bf7\u6c42\u3002<\/li>\n<li><strong>wrapping:<\/strong> \u8fd9\u79cd\u7c7b\u578b\u7684\u5185\u5bb9\u662f\u4ece\u53e6\u5916\u7684http\u5b9e\u4f53\u4e2d\u83b7\u53d6\u7684\u3002<\/li>\n<\/ul>\n<p>\u5f53\u4eceHttp\u54cd\u5e94\u4e2d\u8bfb\u53d6\u5185\u5bb9\u65f6\uff0c\u4e0a\u9762\u7684\u4e09\u79cd\u533a\u5206\u5bf9\u4e8e\u8fde\u63a5\u7ba1\u7406\u5668\u6765\u8bf4\u662f\u975e\u5e38\u91cd\u8981\u7684\u3002\u8bf7\u6c42\u7c7b\u7684\u5b9e\u4f53\u901a\u5e38\u7531\u5e94\u7528\u7a0b\u5e8f\u521b\u5efa\uff0c\u7531HttpClient\u53d1\u9001\u7ed9\u670d\u52a1\u5668\uff0c\u5728\u8bf7\u6c42\u7c7b\u7684\u5b9e\u4f53\u4e2d\uff0cstreamed\u548cself-contained\u4e24\u79cd\u7c7b\u578b\u7684\u533a\u522b\u5c31\u4e0d\u91cd\u8981\u4e86\u3002\u5728\u8fd9\u79cd\u60c5\u51b5\u4e0b\uff0c\u4e00\u822c\u8ba4\u4e3a\u4e0d\u53ef\u91cd\u590d\u7684\u5b9e\u4f53\u662fstreamed\u7c7b\u578b\uff0c\u53ef\u91cd\u590d\u7684\u5b9e\u4f53\u65f6self-contained\u3002<br \/>\n<a name=\"Repeatable-entities\"><\/a><\/p>\n<h4>1.1.4.1. \u53ef\u91cd\u590d\u7684\u5b9e\u4f53<\/h4>\n<p>\u4e00\u4e2a\u5b9e\u4f53\u662f\u53ef\u91cd\u590d\u7684\uff0c\u4e5f\u5c31\u662f\u8bf4\u5b83\u7684\u5305\u542b\u7684\u5185\u5bb9\u53ef\u4ee5\u88ab\u591a\u6b21\u8bfb\u53d6\u3002\u8fd9\u79cd\u591a\u6b21\u8bfb\u53d6\u53ea\u6709self contained\uff08\u81ea\u5305\u542b\uff09\u7684\u5b9e\u4f53\u80fd\u505a\u5230\uff08\u6bd4\u5982<code>ByteArrayEntity<\/code>\u6216\u8005<code>StringEntity<\/code>)\u3002<br \/>\n<a name=\"Using-HTTP-entities\"><\/a><\/p>\n<h4>1.1.4.2. \u4f7f\u7528Http\u5b9e\u4f53<\/h4>\n<p>\u7531\u4e8e\u4e00\u4e2aHttp\u5b9e\u4f53\u65e2\u53ef\u4ee5\u8868\u793a\u4e8c\u8fdb\u5236\u5185\u5bb9\uff0c\u53c8\u53ef\u4ee5\u8868\u793a\u6587\u672c\u5185\u5bb9\uff0c\u6240\u4ee5Http\u5b9e\u4f53\u8981\u652f\u6301\u5b57\u7b26\u7f16\u7801\uff08\u4e3a\u4e86\u652f\u6301\u540e\u8005\uff0c\u5373\u6587\u672c\u5185\u5bb9\uff09\u3002<\/p>\n<p>\u5f53\u9700\u8981\u6267\u884c\u4e00\u4e2a\u5b8c\u6574\u5185\u5bb9\u7684Http\u8bf7\u6c42\u6216\u8005Http\u8bf7\u6c42\u5df2\u7ecf\u6210\u529f\uff0c\u670d\u52a1\u5668\u8981\u53d1\u9001\u54cd\u5e94\u5230\u5ba2\u6237\u7aef\u65f6\uff0cHttp\u5b9e\u4f53\u5c31\u4f1a\u88ab\u521b\u5efa\u3002<\/p>\n<p>\u5982\u679c\u8981\u4eceHttp\u5b9e\u4f53\u4e2d\u8bfb\u53d6\u5185\u5bb9\uff0c\u6211\u4eec\u53ef\u4ee5\u5229\u7528<code>HttpEntity<\/code>\u7c7b\u7684<code>getContent<\/code>\u65b9\u6cd5\u6765\u83b7\u53d6\u5b9e\u4f53\u7684\u8f93\u5165\u6d41\uff08<code>java.io.InputStream<\/code>)\uff0c\u6216\u8005\u5229\u7528<code>HttpEntity<\/code>\u7c7b\u7684<code>writeTo(OutputStream)<\/code>\u65b9\u6cd5\u6765\u83b7\u53d6\u8f93\u51fa\u6d41\uff0c\u8fd9\u4e2a\u65b9\u6cd5\u4f1a\u628a\u6240\u6709\u7684\u5185\u5bb9\u5199\u5165\u5230\u7ed9\u5b9a\u7684\u6d41\u4e2d\u3002<br \/>\n\u5f53\u5b9e\u4f53\u7c7b\u5df2\u7ecf\u88ab\u63a5\u53d7\u540e\uff0c\u6211\u4eec\u53ef\u4ee5\u5229\u7528<code>HttpEntity<\/code>\u7c7b\u7684<code>getContentType()<\/code>\u548c<code>getContentLength()<\/code>\u65b9\u6cd5\u6765\u8bfb\u53d6<code>Content-Type<\/code>\u548c<code>Content-Length<\/code>\u4e24\u4e2a\u5934\u6d88\u606f\uff08\u5982\u679c\u6709\u7684\u8bdd\uff09\u3002\u7531\u4e8e<code>Content-Type<\/code>\u5305\u542bmime-types\u7684\u5b57\u7b26\u7f16\u7801\uff0c\u6bd4\u5982text\/plain\u6216\u8005text\/html,<code>HttpEntity<\/code>\u7c7b\u7684<code>getContentEncoding()<\/code>\u65b9\u6cd5\u5c31\u662f\u8bfb\u53d6\u8fd9\u4e2a\u7f16\u7801\u7684\u3002\u5982\u679c\u5934\u4fe1\u606f\u4e0d\u5b58\u5728\uff0c<code>getContentLength\uff08\uff09<\/code>\u4f1a\u8fd4\u56de-1,<code>getContentType()<\/code>\u4f1a\u8fd4\u56deNULL\u3002\u5982\u679c<code>Content-Type<\/code>\u4fe1\u606f\u5b58\u5728\uff0c\u5c31\u4f1a\u8fd4\u56de\u4e00\u4e2a<code>Header<\/code>\u7c7b\u3002<\/p>\n<p>\u5f53\u4e3a\u53d1\u9001\u6d88\u606f\u521b\u5efaHttp\u5b9e\u4f53\u65f6\uff0c\u9700\u8981\u540c\u65f6\u9644\u52a0meta\u4fe1\u606f\u3002<\/p>\n<pre><code>    StringEntity myEntity = new StringEntity(\"important message\", ContentType.create(\"text\/plain\", \"UTF-8\"));\n    System.out.println(myEntity.getContentType());\n    System.out.println(myEntity.getContentLength());\n    System.out.println(EntityUtils.toString(myEntity));\n    System.out.println(EntityUtils.toByteArray(myEntity).length);\n<\/code><\/pre>\n<p>\u4e0a\u8ff0\u4ee3\u7801\u4f1a\u5728\u63a7\u5236\u53f0\u8f93\u51fa\uff1a<\/p>\n<pre><code>    Content-Type: text\/plain; charset=utf-8\n    17\n    important message\n    17\n<\/code><\/pre>\n<p><a name=\"Ensuring-release-of-low-level-resources\"><\/a><\/p>\n<h3>1.1.5. \u786e\u4fdd\u5e95\u5c42\u7684\u8d44\u6e90\u8fde\u63a5\u88ab\u91ca\u653e<\/h3>\n<p>\u4e3a\u4e86\u786e\u4fdd\u7cfb\u7edf\u8d44\u6e90\u88ab\u6b63\u786e\u5730\u91ca\u653e\uff0c\u6211\u4eec\u8981\u4e48\u7ba1\u7406Http\u5b9e\u4f53\u7684\u5185\u5bb9\u6d41\u3001\u8981\u4e48\u5173\u95edHttp\u54cd\u5e94\u3002<\/p>\n<pre><code>    CloseableHttpClient httpclient =  HttpClients.createDefault();\n    HttpGet httpget = new HttpGet(\"https:\/\/www.yeetrack.com\/\");\n    CloseableHttpResponse response = httpclient.execute(httpget);\n    try {\n        HttpEntity entity = response.getEntity();\n        if (entity != null) {\n            InputStream instream = entity.getContent();\n            try {\n                \/\/ do something useful\n            } finally {\n                instream.close();\n            }\n        }\n    } finally {\n        response.close();\n    }\n<\/code><\/pre>\n<p>\u5173\u95edHttp\u5b9e\u4f53\u5185\u5bb9\u6d41\u548c\u5173\u95edHttp\u54cd\u5e94\u7684\u533a\u522b\u5728\u4e8e\uff0c\u524d\u8005\u901a\u8fc7\u6d88\u8017\u6389Http\u5b9e\u4f53\u5185\u5bb9\u6765\u4fdd\u6301\u76f8\u5173\u7684http\u8fde\u63a5\uff0c\u7136\u540e\u540e\u8005\u4f1a\u7acb\u5373\u5173\u95ed\u3001\u4e22\u5f03http\u8fde\u63a5\u3002<\/p>\n<p>\u8bf7\u6ce8\u610f<code>HttpEntity<\/code>\u7684<code>writeTo(OutputStream)<\/code>\u65b9\u6cd5\uff0c\u5f53Http\u5b9e\u4f53\u88ab\u5199\u5165\u5230OutputStream\u540e\uff0c\u4e5f\u8981\u786e\u4fdd\u91ca\u653e\u7cfb\u7edf\u8d44\u6e90\u3002\u5982\u679c\u8fd9\u4e2a\u65b9\u6cd5\u5185\u8c03\u7528\u4e86<code>HttpEntity<\/code>\u7684<code>getContent()<\/code>\u65b9\u6cd5\uff0c\u90a3\u4e48\u5b83\u4f1a\u6709\u4e00\u4e2a<code>java.io.InpputStream<\/code>\u7684\u5b9e\u4f8b\uff0c\u6211\u4eec\u9700\u8981\u5728finally\u4e2d\u5173\u95ed\u8fd9\u4e2a\u6d41\u3002<\/p>\n<p>\u4f46\u662f\u4e5f\u6709\u8fd9\u6837\u7684\u60c5\u51b5\uff0c\u6211\u4eec\u53ea\u9700\u8981\u83b7\u53d6Http\u54cd\u5e94\u5185\u5bb9\u7684\u4e00\u5c0f\u90e8\u5206\uff0c\u800c\u83b7\u53d6\u6574\u4e2a\u5185\u5bb9\u5e76\u3001\u5b9e\u73b0\u8fde\u63a5\u7684\u53ef\u91cd\u590d\u6027\u4ee3\u4ef7\u592a\u5927\uff0c\u8fd9\u65f6\u6211\u4eec\u53ef\u4ee5\u901a\u8fc7\u5173\u95ed\u54cd\u5e94\u7684\u65b9\u5f0f\u6765\u5173\u95ed\u5185\u5bb9\u8f93\u5165\u3001\u8f93\u51fa\u6d41\u3002<\/p>\n<pre><code>    CloseableHttpClient httpclient = HttpClients.createDefault();\n    HttpGet httpget = new HttpGet(\"https:\/\/www.yeetrack.com\/\");\n    CloseableHttpResponse response = httpclient.execute(httpget);\n    try {\n        HttpEntity entity = response.getEntity();\n        if (entity != null) {\n            InputStream instream = entity.getContent();\n            int byteOne = instream.read();\n            int byteTwo = instream.read();\n            \/\/ Do not need the rest\n    }\n    } finally {\n        response.close();\n    }\n<\/code><\/pre>\n<p>\u4e0a\u9762\u7684\u4ee3\u7801\u6267\u884c\u540e\uff0c\u8fde\u63a5\u53d8\u5f97\u4e0d\u53ef\u7528\uff0c\u6240\u6709\u7684\u8d44\u6e90\u90fd\u5c06\u88ab\u91ca\u653e\u3002<br \/>\n<a name=\"Consuming-entity-content\"><\/a><\/p>\n<h3>1.1.6. \u6d88\u8017Http\u5b9e\u4f53\u5185\u5bb9<\/h3>\n<p>HttpClient\u63a8\u8350\u4f7f\u7528<code>HttpEntity<\/code>\u7684<code>getConent()<\/code>\u65b9\u6cd5\u6216\u8005<code>HttpEntity<\/code>\u7684<code>writeTo(OutputStream)<\/code>\u65b9\u6cd5\u6765\u6d88\u8017\u6389Http\u5b9e\u4f53\u5185\u5bb9\u3002HttpClient\u4e5f\u63d0\u4f9b\u4e86<code>EntityUtils<\/code>\u8fd9\u4e2a\u7c7b\uff0c\u8fd9\u4e2a\u7c7b\u63d0\u4f9b\u4e00\u4e9b\u9759\u6001\u65b9\u6cd5\u53ef\u4ee5\u66f4\u5bb9\u6613\u5730\u8bfb\u53d6Http\u5b9e\u4f53\u7684\u5185\u5bb9\u548c\u4fe1\u606f\u3002\u548c\u4ee5<code>java.io.InputStream<\/code>\u6d41\u8bfb\u53d6\u5185\u5bb9\u7684\u65b9\u5f0f\u76f8\u6bd4\uff0cEntityUtils\u63d0\u4f9b\u7684\u65b9\u6cd5\u53ef\u4ee5\u4ee5\u5b57\u7b26\u4e32\u6216\u8005\u5b57\u8282\u6570\u7ec4\u7684\u5f62\u5f0f\u8bfb\u53d6Http\u5b9e\u4f53\u3002\u4f46\u662f\uff0c\u5f3a\u70c8\u4e0d\u63a8\u8350\u4f7f\u7528<code>EntityUtils<\/code>\u8fd9\u4e2a\u7c7b\uff0c\u9664\u975e\u76ee\u6807\u670d\u52a1\u5668\u53d1\u51fa\u7684\u54cd\u5e94\u662f\u53ef\u4fe1\u4efb\u7684\uff0c\u5e76\u4e14http\u54cd\u5e94\u5b9e\u4f53\u7684\u957f\u5ea6\u4e0d\u4f1a\u8fc7\u5927\u3002<\/p>\n<pre><code>    CloseableHttpClient httpclient = HttpClients.createDefault();\n    HttpGet httpget = new HttpGet(\"https:\/\/www.yeetrack.com\/\");\n    CloseableHttpResponse response = httpclient.execute(httpget);\n    try {\n        HttpEntity entity = response.getEntity();\n        if (entity != null) {\n            long len = entity.getContentLength();\n            if (len != -1 &amp;&amp; len &lt; 2048) {\n                System.out.println(EntityUtils.toString(entity));\n            } else {\n                \/\/ Stream content out\n            }\n        }\n    } finally {\n        response.close();\n    }\n<\/code><\/pre>\n<p>\u6709\u4e9b\u60c5\u51b5\u4e0b\uff0c\u6211\u4eec\u5e0c\u671b\u53ef\u4ee5\u91cd\u590d\u8bfb\u53d6Http\u5b9e\u4f53\u7684\u5185\u5bb9\u3002\u8fd9\u5c31\u9700\u8981\u628aHttp\u5b9e\u4f53\u5185\u5bb9\u7f13\u5b58\u5728\u5185\u5b58\u6216\u8005\u78c1\u76d8\u4e0a\u3002\u6700\u7b80\u5355\u7684\u65b9\u6cd5\u5c31\u662f\u628aHttp Entity\u8f6c\u5316\u6210<code>BufferedHttpEntity<\/code>\uff0c\u8fd9\u6837\u5c31\u628a\u539fHttp\u5b9e\u4f53\u7684\u5185\u5bb9\u7f13\u51b2\u5230\u4e86\u5185\u5b58\u4e2d\u3002\u540e\u9762\u6211\u4eec\u5c31\u53ef\u4ee5\u91cd\u590d\u8bfb\u53d6BufferedHttpEntity\u4e2d\u7684\u5185\u5bb9\u3002<\/p>\n<pre><code>    CloseableHttpResponse response = &lt;...&gt;\n    HttpEntity entity = response.getEntity();\n    if (entity != null) {\n        entity = new BufferedHttpEntity(entity);\n    }\n<\/code><\/pre>\n<p><a name=\"Producing-entity-content\"><\/a><\/p>\n<h3>1.1.7. \u521b\u5efaHttp\u5b9e\u4f53\u5185\u5bb9<\/h3>\n<p>HttpClient\u63d0\u4f9b\u4e86\u4e00\u4e2a\u7c7b\uff0c\u8fd9\u4e9b\u7c7b\u53ef\u4ee5\u901a\u8fc7http\u8fde\u63a5\u9ad8\u6548\u5730\u8f93\u51faHttp\u5b9e\u4f53\u5185\u5bb9\u3002\uff08\u539f\u6587\u662fHttpClient provides several classes that can be used to efficiently stream out content though HTTP connections.\u611f\u89c9thought\u5e94\u8be5\u662fthrought\uff09HttpClient\u63d0\u4f9b\u7684\u8fd9\u51e0\u4e2a\u7c7b\u6db5\u76d6\u7684\u5e38\u89c1\u7684\u6570\u636e\u7c7b\u578b\uff0c\u5982String\uff0cbyte\u6570\u7ec4\uff0c\u8f93\u5165\u6d41\uff0c\u548c\u6587\u4ef6\u7c7b\u578b\uff1a<code>StringEntity<\/code>,<code>ByteArrayEntity<\/code>,<code>InputStreamEntity<\/code>,<code>FileEntity<\/code>\u3002<\/p>\n<pre><code>    File file = new File(\"somefile.txt\");\n    FileEntity entity = new FileEntity(file, ContentType.create(\"text\/plain\", \"UTF-8\"));\n\n    HttpPost httppost = new HttpPost(\"https:\/\/www.yeetrack.com\/action.do\");\n    httppost.setEntity(entity);\n<\/code><\/pre>\n<p>\u8bf7\u6ce8\u610f\u7531\u4e8e<code>InputStreamEntity<\/code>\u53ea\u80fd\u4ece\u4e0b\u5c42\u7684\u6570\u636e\u6d41\u4e2d\u8bfb\u53d6\u4e00\u6b21\uff0c\u6240\u4ee5\u5b83\u662f\u4e0d\u80fd\u91cd\u590d\u7684\u3002\u63a8\u8350\uff0c\u901a\u8fc7\u7ee7\u627f<code>HttpEntity<\/code>\u8fd9\u4e2a\u81ea\u5305\u542b\u7684\u7c7b\u6765\u81ea\u5b9a\u4e49HttpEntity\u7c7b\uff0c\u800c\u4e0d\u662f\u76f4\u63a5\u4f7f\u7528<code>InputStreamEntity<\/code>\u8fd9\u4e2a\u7c7b\u3002<code>FileEntity<\/code>\u5c31\u662f\u4e00\u4e2a\u5f88\u597d\u7684\u8d77\u70b9\uff08FileEntity\u5c31\u662f\u7ee7\u627f\u7684HttpEntity\uff09\u3002<br \/>\n<a name=\"HTML-forms\"><\/a><\/p>\n<h4>1.7.1.1. HTML\u8868\u5355<\/h4>\n<p>\u5f88\u591a\u5e94\u7528\u7a0b\u5e8f\u9700\u8981\u6a21\u62df\u63d0\u4ea4Html\u8868\u5355\u7684\u8fc7\u7a0b\uff0c\u4e3e\u4e2a\u4f8b\u5b50\uff0c\u767b\u9646\u4e00\u4e2a\u7f51\u7ad9\u6216\u8005\u5c06\u8f93\u5165\u5185\u5bb9\u63d0\u4ea4\u7ed9\u670d\u52a1\u5668\u3002HttpClient\u63d0\u4f9b\u4e86<code>UrlEncodedFormEntity<\/code>\u8fd9\u4e2a\u7c7b\u6765\u5e2e\u52a9\u5b9e\u73b0\u8fd9\u4e00\u8fc7\u7a0b\u3002<\/p>\n<pre><code>    List&lt;NameValuePair&gt; formparams = new ArrayList&lt;NameValuePair&gt;();\n    formparams.add(new BasicNameValuePair(\"param1\", \"value1\"));\n    formparams.add(new BasicNameValuePair(\"param2\", \"value2\"));\n    UrlEncodedFormEntity entity = new UrlEncodedFormEntity(formparams, Consts.UTF_8);\n    HttpPost httppost = new HttpPost(\"https:\/\/www.yeetrack.com\/handler.do\");\n    httppost.setEntity(entity);\n<\/code><\/pre>\n<p><code>UrlEncodedFormEntity<\/code>\u5b9e\u4f8b\u4f1a\u4f7f\u7528\u6240\u8c13\u7684Url\u7f16\u7801\u7684\u65b9\u5f0f\u5bf9\u6211\u4eec\u7684\u53c2\u6570\u8fdb\u884c\u7f16\u7801\uff0c\u4ea7\u751f\u7684\u7ed3\u679c\u5982\u4e0b\uff1a<\/p>\n<pre><code>    param1=value1&amp;param2=value2\n<\/code><\/pre>\n<p><a name=\"Content-chunking\"><\/a><\/p>\n<h4>1.1.7.2. \u5185\u5bb9\u5206\u5757<\/h4>\n<p>\u4e00\u822c\u6765\u8bf4\uff0c\u63a8\u8350\u8ba9HttpClient\u81ea\u5df1\u6839\u636eHttp\u6d88\u606f\u4f20\u9012\u7684\u7279\u5f81\u6765\u9009\u62e9\u6700\u5408\u9002\u7684\u4f20\u8f93\u7f16\u7801\u3002\u5f53\u7136\uff0c\u5982\u679c\u975e\u8981\u624b\u52a8\u63a7\u5236\u4e5f\u662f\u53ef\u4ee5\u7684\uff0c\u53ef\u4ee5\u901a\u8fc7\u8bbe\u7f6e<code>HttpEntity<\/code>\u7684<code>setChunked()<\/code>\u4e3atrue\u3002\u8bf7\u6ce8\u610f\uff1aHttpClient\u4ec5\u4f1a\u5c06\u8fd9\u4e2a\u53c2\u6570\u770b\u6210\u662f\u4e00\u4e2a\u5efa\u8bae\u3002\u5982\u679cHttp\u7684\u7248\u672c\uff08\u5982http 1.0)\u4e0d\u652f\u6301\u5185\u5bb9\u5206\u5757\uff0c\u90a3\u4e48\u8fd9\u4e2a\u53c2\u6570\u5c31\u4f1a\u88ab\u5ffd\u7565\u3002<\/p>\n<pre><code>    StringEntity entity = new StringEntity(\"important message\",\n    ContentType.create(\"plain\/text\", Consts.UTF_8));\n    entity.setChunked(true);\n    HttpPost httppost = new HttpPost(\"https:\/\/www.yeetrack.com\/acrtion.do\");\n    httppost.setEntity(entity);\n<\/code><\/pre>\n<p><a name=\"Response-handlers\"><\/a><\/p>\n<h3>1.1.8. Response handlers<\/h3>\n<p>\u6700\u7b80\u5355\u4e5f\u662f\u6700\u65b9\u4fbf\u7684\u5904\u7406http\u54cd\u5e94\u7684\u65b9\u6cd5\u5c31\u662f\u4f7f\u7528<code>ResponseHandler<\/code>\u63a5\u53e3\uff0c\u8fd9\u4e2a\u63a5\u53e3\u4e2d\u6709<code>handleResponse(HttpResponse response)<\/code>\u65b9\u6cd5\u3002\u4f7f\u7528\u8fd9\u4e2a\u65b9\u6cd5\uff0c\u7528\u6237\u5b8c\u5168\u4e0d\u7528\u5173\u5fc3http\u8fde\u63a5\u7ba1\u7406\u5668\u3002\u5f53\u4f7f\u7528<code>ResponseHandler<\/code>\u65f6\uff0cHttpClient\u4f1a\u81ea\u52a8\u5730\u5c06Http\u8fde\u63a5\u91ca\u653e\u7ed9Http\u7ba1\u7406\u5668\uff0c\u5373\u4f7fhttp\u8bf7\u6c42\u5931\u8d25\u4e86\u6216\u8005\u629b\u51fa\u4e86\u5f02\u5e38\u3002<\/p>\n<pre><code>    CloseableHttpClient httpclient = HttpClients.createDefault();\n    HttpGet httpget = new HttpGet(\"https:\/\/www.yeetrack.com\/json\");\n\n    ResponseHandler&lt;MyJsonObject&gt; rh = new ResponseHandler&lt;MyJsonObject&gt;() {\n\n        @Override\n        public JsonObject handleResponse(\n            final HttpResponse response) throws IOException {\n            StatusLine statusLine = response.getStatusLine();\n            HttpEntity entity = response.getEntity();\n            if (statusLine.getStatusCode() &gt;= 300) {\n                throw new HttpResponseException(\n                        statusLine.getStatusCode(),\n                        statusLine.getReasonPhrase());\n            }\n            if (entity == null) {\n                throw new ClientProtocolException(\"Response contains no content\");\n            }\n            Gson gson = new GsonBuilder().create();\n            ContentType contentType = ContentType.getOrDefault(entity);\n            Charset charset = contentType.getCharset();\n            Reader reader = new InputStreamReader(entity.getContent(), charset);\n            return gson.fromJson(reader, MyJsonObject.class);\n        }\n    };\n    \/\/\u8bbe\u7f6eresponseHandler\uff0c\u5f53\u6267\u884chttp\u65b9\u6cd5\u65f6\uff0c\u5c31\u4f1a\u8fd4\u56deMyJsonObject\u5bf9\u8c61\u3002\n    MyJsonObject myjson = client.execute(httpget, rh);\n<\/code><\/pre>\n<p><a name=\"HttpClient-interface\"><\/a><\/p>\n<h2>1.2. HttpClient\u63a5\u53e3<\/h2>\n<p>\u5bf9\u4e8eHttp\u8bf7\u6c42\u6267\u884c\u8fc7\u7a0b\u6765\u8bf4\uff0c<code>HttpClient<\/code>\u7684\u63a5\u53e3\u6709\u7740\u5fc5\u4e0d\u53ef\u5c11\u7684\u4f5c\u7528\u3002<code>HttpClient<\/code>\u63a5\u53e3\u6ca1\u6709\u5bf9Http\u8bf7\u6c42\u7684\u8fc7\u7a0b\u505a\u7279\u522b\u7684\u9650\u5236\u548c\u8be6\u7ec6\u7684\u89c4\u5b9a\uff0c\u8fde\u63a5\u7ba1\u7406\u3001\u72b6\u6001\u7ba1\u7406\u3001\u6388\u6743\u4fe1\u606f\u548c\u91cd\u5b9a\u5411\u5904\u7406\u8fd9\u4e9b\u529f\u80fd\u90fd\u5355\u72ec\u5b9e\u73b0\u3002\u8fd9\u6837\u7528\u6237\u5c31\u53ef\u4ee5\u66f4\u7b80\u5355\u5730\u62d3\u5c55\u63a5\u53e3\u7684\u529f\u80fd\uff08\u6bd4\u5982\u7f13\u5b58\u54cd\u5e94\u5185\u5bb9\uff09\u3002<\/p>\n<p>\u4e00\u822c\u8bf4\u6765\uff0cHttpClient\u5b9e\u9645\u4e0a\u5c31\u662f\u4e00\u7cfb\u5217\u7279\u6b8a\u7684handler\u6216\u8005\u8bf4\u7b56\u7565\u63a5\u53e3\u7684\u5b9e\u73b0\uff0c\u8fd9\u4e9bhandler\uff08\u6d4b\u8bd5\u63a5\u53e3\uff09\u8d1f\u8d23\u7740\u5904\u7406Http\u534f\u8bae\u7684\u67d0\u4e00\u65b9\u9762\uff0c\u6bd4\u5982\u91cd\u5b9a\u5411\u3001\u8ba4\u8bc1\u5904\u7406\u3001\u6709\u5173\u8fde\u63a5\u6301\u4e45\u6027\u548ckeep alive\u6301\u7eed\u65f6\u95f4\u7684\u51b3\u7b56\u3002\u8fd9\u6837\u5c31\u5141\u8bb8\u7528\u6237\u4f7f\u7528\u81ea\u5b9a\u4e49\u7684\u53c2\u6570\u6765\u4ee3\u66ff\u9ed8\u8ba4\u914d\u7f6e\uff0c\u5b9e\u73b0\u4e2a\u6027\u5316\u7684\u529f\u80fd\u3002<\/p>\n<pre><code>    ConnectionKeepAliveStrategy keepAliveStrat = new DefaultConnectionKeepAliveStrategy() {\n\n        @Override\n        public long getKeepAliveDuration(\n            HttpResponse response,\n            HttpContext context) {\n                long keepAlive = super.getKeepAliveDuration(response, context);\n                if (keepAlive == -1) {\n                    \/\/\u5982\u679c\u670d\u52a1\u5668\u6ca1\u6709\u8bbe\u7f6ekeep-alive\u8fd9\u4e2a\u53c2\u6570\uff0c\u6211\u4eec\u5c31\u628a\u5b83\u8bbe\u7f6e\u62105\u79d2\n                    keepAlive = 5000;\n                }\n                return keepAlive;\n        }\n\n    };\n    \/\/\u5b9a\u5236\u6211\u4eec\u81ea\u5df1\u7684httpclient\n    CloseableHttpClient httpclient = HttpClients.custom()\n            .setKeepAliveStrategy(keepAliveStrat)\n            .build();\n<\/code><\/pre>\n<p><a name=\"HttpClient-thread-safety\"><\/a><\/p>\n<h3>1.2.1.HttpClient\u7684\u7ebf\u7a0b\u5b89\u5168\u6027<\/h3>\n<p><code>HttpClient<\/code>\u5df2\u7ecf\u5b9e\u73b0\u4e86\u7ebf\u7a0b\u5b89\u5168\u3002\u6240\u4ee5\u5e0c\u671b\u7528\u6237\u5728\u5b9e\u4f8b\u5316HttpClient\u65f6\uff0c\u4e5f\u8981\u652f\u6301\u4e3a\u591a\u4e2a\u8bf7\u6c42\u4f7f\u7528\u3002<br \/>\n<a name=\"HttpClient-resource-deallocation\"><\/a><\/p>\n<h3>1.2.2.HttpClient\u7684\u5185\u5b58\u5206\u914d<\/h3>\n<p>\u5f53\u4e00\u4e2a<code>CloseableHttpClient<\/code>\u7684\u5b9e\u4f8b\u4e0d\u518d\u88ab\u4f7f\u7528\uff0c\u5e76\u4e14\u5b83\u7684\u4f5c\u7528\u8303\u56f4\u5373\u5c06\u5931\u6548\uff0c\u548c\u5b83\u76f8\u5173\u7684\u8fde\u63a5\u5fc5\u987b\u88ab\u5173\u95ed\uff0c\u5173\u95ed\u65b9\u6cd5\u53ef\u4ee5\u8c03\u7528<code>CloseableHttpClient<\/code>\u7684<code>close()<\/code>\u65b9\u6cd5\u3002<\/p>\n<pre><code>    CloseableHttpClient httpclient = HttpClients.createDefault();\n    try {\n        &lt;...&gt;\n    } finally {\n        \/\/\u5173\u95ed\u8fde\u63a5\n        httpclient.close();\n    }\n<\/code><\/pre>\n<p><a name=\"HTTP-execution-context\"><\/a><\/p>\n<h2>1.3.Http\u6267\u884c\u4e0a\u4e0b\u6587<\/h2>\n<p>\u6700\u521d\uff0cHttp\u88ab\u8bbe\u8ba1\u6210\u4e00\u79cd\u65e0\u72b6\u6001\u7684\u3001\u9762\u5411\u8bf7\u6c42-\u54cd\u5e94\u7684\u534f\u8bae\u3002\u7136\u800c\uff0c\u5728\u5b9e\u9645\u4f7f\u7528\u4e2d\uff0c\u6211\u4eec\u5e0c\u671b\u80fd\u591f\u5728\u4e00\u4e9b\u903b\u8f91\u76f8\u5173\u7684\u8bf7\u6c42-\u54cd\u5e94\u4e2d\uff0c\u4fdd\u6301\u72b6\u6001\u4fe1\u606f\u3002\u4e3a\u4e86\u4f7f\u5e94\u7528\u7a0b\u5e8f\u53ef\u4ee5\u4fdd\u6301Http\u7684\u6301\u7eed\u72b6\u6001\uff0cHttpClient\u5141\u8bb8http\u8fde\u63a5\u5728\u7279\u5b9a\u7684Http\u4e0a\u4e0b\u6587\u4e2d\u6267\u884c\u3002\u5982\u679c\u5728\u6301\u7eed\u7684http\u8bf7\u6c42\u4e2d\u4f7f\u7528\u4e86\u540c\u6837\u7684\u4e0a\u4e0b\u6587\uff0c\u90a3\u4e48\u8fd9\u4e9b\u8bf7\u6c42\u5c31\u53ef\u4ee5\u88ab\u5206\u914d\u5230\u4e00\u4e2a\u903b\u8f91\u4f1a\u8bdd\u4e2d\u3002HTTP\u4e0a\u4e0b\u6587\u5c31\u548c\u4e00\u4e2a<code>java.util.Map&lt;String, Object&gt;<\/code>\u529f\u80fd\u7c7b\u4f3c\u3002\u5b83\u5b9e\u9645\u4e0a\u5c31\u662f\u4e00\u4e2a\u4efb\u610f\u547d\u540d\u7684\u503c\u7684\u96c6\u5408\u3002\u5e94\u7528\u7a0b\u5e8f\u53ef\u4ee5\u5728Http\u8bf7\u6c42\u6267\u884c\u524d\u586b\u5145\u4e0a\u4e0b\u6587\u7684\u503c\uff0c\u4e5f\u53ef\u4ee5\u5728\u8bf7\u6c42\u6267\u884c\u5b8c\u6bd5\u540e\u68c0\u67e5\u4e0a\u4e0b\u6587\u3002<\/p>\n<p><code>HttpContext<\/code>\u53ef\u4ee5\u5305\u542b\u4efb\u610f\u7c7b\u578b\u7684\u5bf9\u8c61\uff0c\u56e0\u6b64\u5982\u679c\u5728\u591a\u7ebf\u7a0b\u4e2d\u5171\u4eab\u4e0a\u4e0b\u6587\u4f1a\u4e0d\u5b89\u5168\u3002\u63a8\u8350\u6bcf\u4e2a\u7ebf\u7a0b\u90fd\u53ea\u5305\u542b\u81ea\u5df1\u7684http\u4e0a\u4e0b\u6587\u3002<\/p>\n<p>\u5728Http\u8bf7\u6c42\u6267\u884c\u7684\u8fc7\u7a0b\u4e2d\uff0cHttpClient\u4f1a\u81ea\u52a8\u6dfb\u52a0\u4e0b\u9762\u7684\u5c5e\u6027\u5230Http\u4e0a\u4e0b\u6587\u4e2d\uff1a<\/p>\n<ul>\n<li><code>HttpConnection<\/code>\u7684\u5b9e\u4f8b\uff0c\u8868\u793a\u5ba2\u6237\u7aef\u4e0e\u670d\u52a1\u5668\u4e4b\u95f4\u7684\u8fde\u63a5<\/li>\n<li><code>HttpHost<\/code>\u7684\u5b9e\u4f8b\uff0c\u8868\u793a\u8981\u8fde\u63a5\u7684\u6728\u5305\u670d\u52a1\u5668<\/li>\n<li><code>HttpRoute<\/code>\u7684\u5b9e\u4f8b\uff0c\u8868\u793a\u5168\u90e8\u7684\u8fde\u63a5\u8def\u7531<\/li>\n<li><code>HttpRequest<\/code>\u7684\u5b9e\u4f8b\uff0c\u8868\u793aHttp\u8bf7\u6c42\u3002\u5728\u6267\u884c\u4e0a\u4e0b\u6587\u4e2d\uff0c\u6700\u7ec8\u7684HttpRequest\u5bf9\u8c61\u4f1a\u4ee3\u8868http\u6d88\u606f\u7684\u72b6\u6001\u3002Http\/1.0\u548cHttp\/1.1\u90fd\u9ed8\u8ba4\u4f7f\u7528\u76f8\u5bf9\u7684uri\u3002\u4f46\u662f\u5982\u679c\u4f7f\u7528\u4e86\u975e\u96a7\u9053\u6a21\u5f0f\u7684\u4ee3\u7406\u670d\u52a1\u5668\uff0c\u5c31\u4f1a\u4f7f\u7528\u7edd\u5bf9\u8def\u5f84\u7684uri\u3002<\/li>\n<li><code>HttpResponse<\/code>\u7684\u5b9e\u4f8b\uff0c\u8868\u793aHttp\u54cd\u5e94<\/li>\n<li><code>java.lang.Boolean<\/code>\u5bf9\u8c61\uff0c\u8868\u793a\u662f\u5426\u8bf7\u6c42\u88ab\u6210\u529f\u7684\u53d1\u9001\u7ed9\u76ee\u6807\u670d\u52a1\u5668<\/li>\n<li><code>RequestConfig<\/code>\u5bf9\u8c61\uff0c\u8868\u793ahttp request\u7684\u914d\u7f6e\u4fe1\u606f<\/li>\n<li><code>java.util.List&lt;Uri&gt;<\/code>\u5bf9\u8c61\uff0c\u8868\u793aHttp\u54cd\u5e94\u4e2d\u7684\u6240\u6709\u91cd\u5b9a\u5411\u5730\u5740<\/li>\n<\/ul>\n<p>\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528<code>HttpClientContext<\/code>\u8fd9\u4e2a\u9002\u914d\u5668\u6765\u7b80\u5316\u548c\u4e0a\u4e0b\u6587\u4ea4\u4e92\u7684\u8fc7\u7a0b\u3002<\/p>\n<pre><code>    HttpContext context = &lt;...&gt;\n    HttpClientContext clientContext = HttpClientContext.adapt(context);\n    HttpHost target = clientContext.getTargetHost();\n    HttpRequest request = clientContext.getRequest();\n    HttpResponse response = clientContext.getResponse();\n    RequestConfig config = clientContext.getRequestConfig();\n<\/code><\/pre>\n<p>\u540c\u4e00\u4e2a\u903b\u8f91\u4f1a\u8bdd\u4e2d\u7684\u591a\u4e2aHttp\u8bf7\u6c42\uff0c\u5e94\u8be5\u4f7f\u7528\u76f8\u540c\u7684Http\u4e0a\u4e0b\u6587\u6765\u6267\u884c\uff0c\u8fd9\u6837\u5c31\u53ef\u4ee5\u81ea\u52a8\u5730\u5728http\u8bf7\u6c42\u4e2d\u4f20\u9012\u4f1a\u8bdd\u4e0a\u4e0b\u6587\u548c\u72b6\u6001\u4fe1\u606f\u3002<br \/>\n\u5728\u4e0b\u9762\u7684\u4f8b\u5b50\u4e2d\uff0c\u6211\u4eec\u5728\u5f00\u5934\u8bbe\u7f6e\u7684\u53c2\u6570\uff0c\u4f1a\u88ab\u4fdd\u5b58\u5728\u4e0a\u4e0b\u6587\u4e2d\uff0c\u5e76\u4e14\u4f1a\u5e94\u7528\u5230\u540e\u7eed\u7684http\u8bf7\u6c42\u4e2d\uff08\u6e90\u82f1\u6587\u4e2d\u6709\u4e2a\u62fc\u5199\u9519\u8bef\uff09\u3002<\/p>\n<pre><code>    CloseableHttpClient httpclient = HttpClients.createDefault();\n    RequestConfig requestConfig = RequestConfig.custom()\n            .setSocketTimeout(1000)\n            .setConnectTimeout(1000)\n            .build();\n\n    HttpGet httpget1 = new HttpGet(\"https:\/\/www.yeetrack.com\/1\");\n    httpget1.setConfig(requestConfig);\n    CloseableHttpResponse response1 = httpclient.execute(httpget1, context);\n    try {\n        HttpEntity entity1 = response1.getEntity();\n    } finally {\n        response1.close();\n    }\n    \/\/httpget2\u88ab\u6267\u884c\u65f6\uff0c\u4e5f\u4f1a\u4f7f\u7528httpget1\u7684\u4e0a\u4e0b\u6587\n    HttpGet httpget2 = new HttpGet(\"https:\/\/www.yeetrack.com\/2\");\n    CloseableHttpResponse response2 = httpclient.execute(httpget2, context);\n    try {\n        HttpEntity entity2 = response2.getEntity();\n    } finally {\n        response2.close();\n    }\n<\/code><\/pre>\n<p><a name=\"Exception-handling\"><\/a><\/p>\n<h2>1.4. \u5f02\u5e38\u5904\u7406<\/h2>\n<p>HttpClient\u4f1a\u88ab\u629b\u51fa\u4e24\u79cd\u7c7b\u578b\u7684\u5f02\u5e38\uff0c\u4e00\u79cd\u662f<code>java.io.IOException<\/code>\uff0c\u5f53\u9047\u5230I\/O\u5f02\u5e38\u65f6\u629b\u51fa\uff08socket\u8d85\u65f6\uff0c\u6216\u8005socket\u88ab\u91cd\u7f6e\uff09;\u53e6\u4e00\u79cd\u662f<code>HttpException<\/code>,\u8868\u793aHttp\u5931\u8d25\uff0c\u5982Http\u534f\u8bae\u4f7f\u7528\u4e0d\u6b63\u786e\u3002\u901a\u5e38\u8ba4\u4e3a\uff0cI\/O\u9519\u8bef\u65f6\u4e0d\u81f4\u547d\u3001\u53ef\u4fee\u590d\u7684\uff0c\u800cHttp\u534f\u8bae\u9519\u8bef\u662f\u81f4\u547d\u4e86\uff0c\u4e0d\u80fd\u81ea\u52a8\u4fee\u590d\u7684\u9519\u8bef\u3002<br \/>\n<a name=\"HTTP-transport-safety\"><\/a><\/p>\n<h3>1.4.1.HTTP\u4f20\u8f93\u5b89\u5168<\/h3>\n<p>Http\u534f\u8bae\u4e0d\u80fd\u6ee1\u8db3\u6240\u6709\u7c7b\u578b\u7684\u5e94\u7528\u573a\u666f\uff0c\u6211\u4eec\u9700\u8981\u77e5\u9053\u8fd9\u70b9\u3002Http\u662f\u4e2a\u7b80\u5355\u7684\u9762\u5411\u534f\u8bae\u7684\u8bf7\u6c42\/\u54cd\u5e94\u7684\u534f\u8bae\uff0c\u5f53\u521d\u5b83\u88ab\u8bbe\u8ba1\u7528\u6765\u652f\u6301\u9759\u6001\u6216\u8005\u52a8\u6001\u751f\u6210\u7684\u5185\u5bb9\u68c0\u7d22\uff0c\u4e4b\u524d\u4ece\u6765\u6ca1\u6709\u4eba\u60f3\u8fc7\u8ba9\u5b83\u652f\u6301\u4e8b\u52a1\u6027\u64cd\u4f5c\u3002\u4f8b\u5982\uff0cHttp\u670d\u52a1\u5668\u6210\u529f\u63a5\u6536\u3001\u5904\u7406\u8bf7\u6c42\u540e\uff0c\u751f\u6210\u54cd\u5e94\u6d88\u606f\uff0c\u5e76\u4e14\u628a\u72b6\u6001\u7801\u53d1\u9001\u7ed9\u5ba2\u6237\u7aef\uff0c\u8fd9\u4e2a\u8fc7\u7a0b\u662fHttp\u534f\u8bae\u5e94\u8be5\u4fdd\u8bc1\u7684\u3002\u4f46\u662f\uff0c\u5982\u679c\u5ba2\u6237\u7aef\u7531\u4e8e\u8bfb\u53d6\u8d85\u65f6\u3001\u53d6\u6d88\u8bf7\u6c42\u6216\u8005\u7cfb\u7edf\u5d29\u6e83\u5bfc\u81f4\u63a5\u6536\u54cd\u5e94\u5931\u8d25\uff0c\u670d\u52a1\u5668\u4e0d\u4f1a\u56de\u6eda\u8fd9\u4e00\u4e8b\u52a1\u3002\u5982\u679c\u5ba2\u6237\u7aef\u91cd\u65b0\u53d1\u9001\u8fd9\u4e2a\u8bf7\u6c42\uff0c\u670d\u52a1\u5668\u5c31\u4f1a\u91cd\u590d\u7684\u89e3\u6790\u3001\u6267\u884c\u8fd9\u4e2a\u4e8b\u52a1\u3002\u5728\u4e00\u4e9b\u60c5\u51b5\u4e0b\uff0c\u8fd9\u4f1a\u5bfc\u81f4\u5e94\u7528\u7a0b\u5e8f\u7684\u6570\u636e\u635f\u574f\u548c\u5e94\u7528\u7a0b\u5e8f\u7684\u72b6\u6001\u4e0d\u4e00\u81f4\u3002<\/p>\n<p>\u5373\u4f7fHttp\u5f53\u521d\u8bbe\u8ba1\u662f\u4e0d\u652f\u6301\u4e8b\u52a1\u64cd\u4f5c\uff0c\u4f46\u662f\u5b83\u4ecd\u65e7\u53ef\u4ee5\u4f5c\u4e3a\u4f20\u8f93\u534f\u8bae\u4e3a\u67d0\u4e9b\u5173\u952e\u7a0b\u5e8f\u63d0\u4f9b\u670d\u52a1\u3002\u4e3a\u4e86\u4fdd\u8bc1Http\u4f20\u8f93\u5c42\u7684\u5b89\u5168\u6027\uff0c\u7cfb\u7edf\u5fc5\u987b\u4fdd\u8bc1\u5e94\u7528\u5c42\u4e0a\u7684http\u65b9\u6cd5\u7684\u5e42\u7b49\u6027\uff08To ensure HTTP transport layer safety the system must ensure the idempotency of HTTP methods on the application layer\uff09\u3002<br \/>\n<a name=\"Idempotent-methods\"><\/a><\/p>\n<h3>1.4.2.\u65b9\u6cd5\u7684\u5e42\u7b49\u6027<\/h3>\n<p>HTTP\/1.1\u89c4\u8303\u4e2d\u662f\u8fd9\u6837\u5b9a\u4e49\u5e42\u7b49\u65b9\u6cd5\u7684\uff0cMethods can also have the property of \"idempotence\" in that (aside from error or expiration issues) the side-effects of N &gt; 0 identical requests is the same as for a single request\u3002\u7528\u5176\u4ed6\u8bdd\u6765\u8bf4\uff0c\u5e94\u7528\u7a0b\u5e8f\u9700\u8981\u6b63\u786e\u5730\u5904\u7406\u540c\u4e00\u65b9\u6cd5\u591a\u6b21\u6267\u884c\u9020\u6210\u7684\u5f71\u54cd\u3002\u6dfb\u52a0\u4e00\u4e2a\u5177\u6709\u552f\u4e00\u6027\u7684id\u5c31\u80fd\u907f\u514d\u91cd\u590d\u6267\u884c\u540c\u4e00\u4e2a\u903b\u8f91\u8bf7\u6c42\uff0c\u95ee\u9898\u89e3\u51b3\u3002<\/p>\n<p>\u8bf7\u77e5\u6653\uff0c\u8fd9\u4e2a\u95ee\u9898\u4e0d\u53ea\u662fHttpClient\u624d\u4f1a\u6709\uff0c\u57fa\u4e8e\u6d4f\u89c8\u5668\u7684\u5e94\u7528\u7a0b\u5e8f\u4e5f\u4f1a\u9047\u5230Http\u65b9\u6cd5\u4e0d\u5e42\u7b49\u7684\u95ee\u9898\u3002<\/p>\n<p>HttpClient\u9ed8\u8ba4\u628a\u975e\u5b9e\u4f53\u65b9\u6cd5<code>get<\/code>\u3001<code>head<\/code>\u65b9\u6cd5\u770b\u505a\u5e42\u7b49\u65b9\u6cd5\uff0c\u628a\u5b9e\u4f53\u65b9\u6cd5<code>post<\/code>\u3001<code>put<\/code>\u65b9\u6cd5\u770b\u505a\u975e\u5e42\u7b49\u65b9\u6cd5\u3002<br \/>\n<a name=\"Automatic-exception-recovery\"><\/a><\/p>\n<h3>1.4.3.\u5f02\u5e38\u81ea\u52a8\u4fee\u590d<\/h3>\n<p>\u9ed8\u8ba4\u60c5\u51b5\u4e0b\uff0cHttpClient\u4f1a\u5c1d\u8bd5\u81ea\u52a8\u4fee\u590dI\/O\u5f02\u5e38\u3002\u8fd9\u79cd\u81ea\u52a8\u4fee\u590d\u4ec5\u9650\u4e8e\u4fee\u590d\u51e0\u4e2a\u516c\u8ba4\u5b89\u5168\u7684\u5f02\u5e38\u3002<\/p>\n<ul>\n<li>HttpClient\u4e0d\u4f1a\u5c1d\u8bd5\u4fee\u590d\u4efb\u4f55\u903b\u8f91\u6216\u8005http\u534f\u8bae\u9519\u8bef\uff08\u5373\u4eceHttpException\u884d\u751f\u51fa\u6765\u7684\u5f02\u5e38\uff09\u3002<\/li>\n<li>HttpClient\u4f1a\u81ea\u52a8\u518d\u6b21\u53d1\u9001\u5e42\u7b49\u7684\u65b9\u6cd5\uff08\u5982\u679c\u9996\u6b21\u6267\u884c\u5931\u8d25\u3002<\/li>\n<li>HttpClient\u4f1a\u81ea\u52a8\u518d\u6b21\u53d1\u9001\u9047\u5230transport\u5f02\u5e38\u7684\u65b9\u6cd5\uff0c\u524d\u63d0\u662fHttp\u8bf7\u6c42\u4ecd\u65e7\u4fdd\u6301\u7740\u8fde\u63a5\uff08\u4f8b\u5982http\u8bf7\u6c42\u6ca1\u6709\u5168\u90e8\u53d1\u9001\u7ed9\u76ee\u6807\u670d\u52a1\u5668\uff0cHttpClient\u4f1a\u518d\u6b21\u5c1d\u8bd5\u53d1\u9001\uff09\u3002<\/li>\n<\/ul>\n<p><a name=\"Request-retry-handler\"><\/a><\/p>\n<h3>1.4.4.\u8bf7\u6c42\u91cd\u8bd5handler<\/h3>\n<p>\u5982\u679c\u8981\u81ea\u5b9a\u4e49\u5f02\u5e38\u5904\u7406\u673a\u5236\uff0c\u6211\u4eec\u9700\u8981\u5b9e\u73b0<code>HttpRequestRetryHandler<\/code>\u63a5\u53e3\u3002<\/p>\n<pre><code>    HttpRequestRetryHandler myRetryHandler = new HttpRequestRetryHandler() {\n\n        public boolean retryRequest(\n                IOException exception,\n                int executionCount,\n                HttpContext context) {\n            if (executionCount &gt;= 5) {\n                \/\/ \u5982\u679c\u5df2\u7ecf\u91cd\u8bd5\u4e865\u6b21\uff0c\u5c31\u653e\u5f03\n                return false;\n            }\n            if (exception instanceof InterruptedIOException) {\n                \/\/ \u8d85\u65f6\n                return false;\n            }\n            if (exception instanceof UnknownHostException) {\n                \/\/ \u76ee\u6807\u670d\u52a1\u5668\u4e0d\u53ef\u8fbe\n                return false;\n            }\n            if (exception instanceof ConnectTimeoutException) {\n                \/\/ \u8fde\u63a5\u88ab\u62d2\u7edd\n                return false;\n            }\n            if (exception instanceof SSLException) {\n                \/\/ ssl\u63e1\u624b\u5f02\u5e38\n                return false;\n            }\n            HttpClientContext clientContext = HttpClientContext.adapt(context);\n            HttpRequest request = clientContext.getRequest();\n            boolean idempotent = !(request instanceof HttpEntityEnclosingRequest);\n            if (idempotent) {\n                \/\/ \u5982\u679c\u8bf7\u6c42\u662f\u5e42\u7b49\u7684\uff0c\u5c31\u518d\u6b21\u5c1d\u8bd5\n                return true;\n            }\n            return false;\n        }\n\n    };  \n    CloseableHttpClient httpclient = HttpClients.custom()\n            .setRetryHandler(myRetryHandler)\n            .build();\n<\/code><\/pre>\n<p><a name=\"Aborting-requests\"><\/a><\/p>\n<h2>1.5.\u7ec8\u6b62\u8bf7\u6c42<\/h2>\n<p>\u6709\u65f6\u5019\u7531\u4e8e\u76ee\u6807\u670d\u52a1\u5668\u8d1f\u8f7d\u8fc7\u9ad8\u6216\u8005\u5ba2\u6237\u7aef\u76ee\u524d\u6709\u592a\u591a\u8bf7\u6c42\u79ef\u538b\uff0chttp\u8bf7\u6c42\u4e0d\u80fd\u5728\u6307\u5b9a\u65f6\u95f4\u5185\u6267\u884c\u5b8c\u6bd5\u3002\u8fd9\u65f6\u5019\u7ec8\u6b62\u8fd9\u4e2a\u8bf7\u6c42\uff0c\u91ca\u653e\u963b\u585eI\/O\u7684\u8fdb\u7a0b\uff0c\u5c31\u663e\u5f97\u5f88\u5fc5\u8981\u3002\u901a\u8fc7HttpClient\u6267\u884c\u7684Http\u8bf7\u6c42\uff0c\u5728\u4efb\u4f55\u72b6\u6001\u4e0b\u90fd\u80fd\u901a\u8fc7\u8c03\u7528<code>HttpUriRequest<\/code>\u7684<code>abort()<\/code>\u65b9\u6cd5\u6765\u7ec8\u6b62\u3002\u8fd9\u4e2a\u65b9\u6cd5\u662f\u7ebf\u7a0b\u5b89\u5168\u7684\uff0c\u5e76\u4e14\u80fd\u5728\u4efb\u4f55\u7ebf\u7a0b\u4e2d\u8c03\u7528\u3002\u5f53Http\u8bf7\u6c42\u88ab\u7ec8\u6b62\u4e86\uff0c\u672c\u7ebf\u7a0b\uff08\u5373\u4f7f\u73b0\u5728\u6b63\u5728\u963b\u585eI\/O\uff09\u4e5f\u4f1a\u901a\u8fc7\u629b\u51fa\u4e00\u4e2a<code>InterruptedIOException<\/code>\u5f02\u5e38\uff0c\u6765\u91ca\u653e\u8d44\u6e90\u3002<br \/>\n<a name=\"HTTP-protocol-interceptors\"><\/a><\/p>\n<h2>1.6. Http\u534f\u8bae\u62e6\u622a\u5668<\/h2>\n<p>HTTP\u534f\u8bae\u62e6\u622a\u5668\u662f\u4e00\u79cd\u5b9e\u73b0\u4e00\u4e2a\u7279\u5b9a\u7684\u65b9\u9762\u7684HTTP\u534f\u8bae\u7684\u4ee3\u7801\u7a0b\u5e8f\u3002\u901a\u5e38\u60c5\u51b5\u4e0b\uff0c\u534f\u8bae\u62e6\u622a\u5668\u4f1a\u5c06\u4e00\u4e2a\u6216\u591a\u4e2a\u5934\u6d88\u606f\u52a0\u5165\u5230\u63a5\u53d7\u6216\u8005\u53d1\u9001\u7684\u6d88\u606f\u4e2d\u3002\u534f\u8bae\u62e6\u622a\u5668\u4e5f\u53ef\u4ee5\u64cd\u4f5c\u6d88\u606f\u7684\u5185\u5bb9\u5b9e\u4f53---\u6d88\u606f\u5185\u5bb9\u7684\u538b\u7f29\/\u89e3\u538b\u7f29\u5c31\u662f\u4e2a\u5f88\u597d\u7684\u4f8b\u5b50\u3002\u901a\u5e38\uff0c\u8fd9\u662f\u901a\u8fc7\u4f7f\u7528\u201c\u88c5\u9970\u201d\u5f00\u53d1\u6a21\u5f0f\uff0c\u4e00\u4e2a\u5305\u88c5\u5b9e\u4f53\u7c7b\u7528\u4e8e\u88c5\u9970\u539f\u6765\u7684\u5b9e\u4f53\u6765\u5b9e\u73b0\u3002\u4e00\u4e2a\u62e6\u622a\u5668\u53ef\u4ee5\u5408\u5e76\uff0c\u5f62\u6210\u4e00\u4e2a\u903b\u8f91\u5355\u5143\u3002<\/p>\n<p>\u534f\u8bae\u62e6\u622a\u5668\u53ef\u4ee5\u901a\u8fc7\u5171\u4eab\u4fe1\u606f\u534f\u4f5c\u2014\u2014\u6bd4\u5982\u5904\u7406\u72b6\u6001\u2014\u2014\u901a\u8fc7HTTP\u6267\u884c\u4e0a\u4e0b\u6587\u3002\u534f\u8bae\u62e6\u622a\u5668\u53ef\u4ee5\u4f7f\u7528Http\u4e0a\u4e0b\u6587\u5b58\u50a8\u4e00\u4e2a\u6216\u8005\u591a\u4e2a\u8fde\u7eed\u8bf7\u6c42\u7684\u5904\u7406\u72b6\u6001\u3002<\/p>\n<p>\u901a\u5e38\uff0c\u53ea\u8981\u62e6\u622a\u5668\u4e0d\u4f9d\u8d56\u4e8e\u4e00\u4e2a\u7279\u5b9a\u72b6\u6001\u7684http\u4e0a\u4e0b\u6587\uff0c\u90a3\u4e48\u62e6\u622a\u6267\u884c\u7684\u987a\u5e8f\u5c31\u65e0\u6240\u8c13\u3002\u5982\u679c\u534f\u8bae\u62e6\u622a\u5668\u6709\u76f8\u4e92\u4f9d\u8d56\u5173\u7cfb\uff0c\u5fc5\u987b\u4ee5\u7279\u5b9a\u7684\u987a\u5e8f\u6267\u884c\uff0c\u90a3\u4e48\u5b83\u4eec\u5e94\u8be5\u6309\u7167\u7279\u5b9a\u7684\u987a\u5e8f\u52a0\u5165\u5230\u534f\u8bae\u5904\u7406\u5668\u4e2d\u3002<\/p>\n<p>\u534f\u8bae\u5904\u7406\u5668\u5fc5\u987b\u662f\u7ebf\u7a0b\u5b89\u5168\u7684\u3002\u7c7b\u4f3c\u4e8eservlets\uff0c\u534f\u8bae\u62e6\u622a\u5668\u4e0d\u5e94\u8be5\u4f7f\u7528\u53d8\u91cf\u5b9e\u4f53\uff0c\u9664\u975e\u8bbf\u95ee\u8fd9\u4e9b\u53d8\u91cf\u662f\u540c\u6b65\u7684\uff08\u7ebf\u7a0b\u5b89\u5168\u7684\uff09\u3002<\/p>\n<p>\u4e0b\u9762\u662f\u4e2a\u4f8b\u5b50\uff0c\u8bb2\u8ff0\u4e86\u672c\u5730\u7684\u4e0a\u4e0b\u6587\u65f6\u5982\u4f55\u5728\u8fde\u7eed\u8bf7\u6c42\u4e2d\u8bb0\u5f55\u5904\u7406\u72b6\u6001\u7684\uff1a<\/p>\n<pre><code>    CloseableHttpClient httpclient = HttpClients.custom()\n            .addInterceptorLast(new HttpRequestInterceptor() {\n\n                public void process(\n                        final HttpRequest request,\n                        final HttpContext context) throws HttpException, IOException {\n                        \/\/AtomicInteger\u662f\u4e2a\u7ebf\u7a0b\u5b89\u5168\u7684\u6574\u578b\u7c7b\n                    AtomicInteger count = (AtomicInteger) context.getAttribute(\"count\");\n                    request.addHeader(\"Count\", Integer.toString(count.getAndIncrement()));\n                }\n\n            })\n            .build();\n\n    AtomicInteger count = new AtomicInteger(1);\n    HttpClientContext localContext = HttpClientContext.create();\n    localContext.setAttribute(\"count\", count);\n\n    HttpGet httpget = new HttpGet(\"https:\/\/www.yeetrack.com\/\");\n    for (int i = 0; i &lt; 10; i++) {\n        CloseableHttpResponse response = httpclient.execute(httpget, localContext);\n        try {\n            HttpEntity entity = response.getEntity();\n        } finally {\n            response.close();\n        }\n    }\n<\/code><\/pre>\n<p>\u4e0a\u9762\u4ee3\u7801\u5728\u53d1\u9001http\u8bf7\u6c42\u65f6\uff0c\u4f1a\u81ea\u52a8\u6dfb\u52a0Count\u8fd9\u4e2aheader\uff0c\u53ef\u4ee5\u4f7f\u7528wireshark\u6293\u5305\u67e5\u770b\u3002<br \/>\n<a name=\"Redirect-handling\"><\/a><\/p>\n<h2>1.7.1. \u91cd\u5b9a\u5411\u5904\u7406<\/h2>\n<p>HttpClient\u4f1a\u81ea\u52a8\u5904\u7406\u6240\u6709\u7c7b\u578b\u7684\u91cd\u5b9a\u5411\uff0c\u9664\u4e86\u90a3\u4e9bHttp\u89c4\u8303\u660e\u786e\u7981\u6b62\u7684\u91cd\u5b9a\u5411\u3002See Other (status code 303) redirects on POST and PUT requests are converted to GET requests as required by the HTTP specification. \u6211\u4eec\u53ef\u4ee5\u4f7f\u7528\u81ea\u5b9a\u4e49\u7684\u91cd\u5b9a\u5411\u7b56\u7565\u6765\u653e\u677eHttp\u89c4\u8303\u5bf9Post\u65b9\u6cd5\u91cd\u5b9a\u5411\u7684\u9650\u5236\u3002<\/p>\n<pre><code>    \/\/LaxRedirectStrategy\u53ef\u4ee5\u81ea\u52a8\u91cd\u5b9a\u5411\u6240\u6709\u7684HEAD\uff0cGET\uff0cPOST\u8bf7\u6c42\uff0c\u89e3\u9664\u4e86http\u89c4\u8303\u5bf9post\u8bf7\u6c42\u91cd\u5b9a\u5411\u7684\u9650\u5236\u3002\n    LaxRedirectStrategy redirectStrategy = new LaxRedirectStrategy();\n    CloseableHttpClient httpclient = HttpClients.custom()\n            .setRedirectStrategy(redirectStrategy)\n            .build();\n<\/code><\/pre>\n<p>HttpClient\u5728\u8bf7\u6c42\u6267\u884c\u8fc7\u7a0b\u4e2d\uff0c\u7ecf\u5e38\u9700\u8981\u91cd\u5199\u8bf7\u6c42\u7684\u6d88\u606f\u3002 HTTP\/1.0\u548cHTTP\/1.1\u90fd\u9ed8\u8ba4\u4f7f\u7528\u76f8\u5bf9\u7684uri\u8def\u5f84\u3002\u540c\u6837\uff0c\u539f\u59cb\u7684\u8bf7\u6c42\u53ef\u80fd\u4f1a\u88ab\u4e00\u6b21\u6216\u8005\u591a\u6b21\u7684\u91cd\u5b9a\u5411\u3002\u6700\u7ec8\u7ed3\u5bf9\u8def\u5f84\u7684\u89e3\u91ca\u53ef\u4ee5\u4f7f\u7528\u6700\u521d\u7684\u8bf7\u6c42\u548c\u4e0a\u4e0b\u6587\u3002<code>URIUtils<\/code>\u7c7b\u7684<code>resolve<\/code>\u65b9\u6cd5\u53ef\u4ee5\u7528\u4e8e\u5c06\u62e6\u622a\u7684\u7edd\u5bf9\u8def\u5f84\u6784\u5efa\u6210\u6700\u7ec8\u7684\u8bf7\u6c42\u3002\u8fd9\u4e2a\u65b9\u6cd5\u5305\u542b\u4e86\u6700\u540e\u4e00\u4e2a\u5206\u7247\u6807\u8bc6\u7b26\u6216\u8005\u539f\u59cb\u8bf7\u6c42\u3002<\/p>\n<pre><code>    CloseableHttpClient httpclient = HttpClients.createDefault();\n    HttpClientContext context = HttpClientContext.create();\n    HttpGet httpget = new HttpGet(\"https:\/\/www.yeetrack.com:8080\/\");\n    CloseableHttpResponse response = httpclient.execute(httpget, context);\n    try {\n        HttpHost target = context.getTargetHost();\n        List&lt;URI&gt; redirectLocations = context.getRedirectLocations();\n        URI location = URIUtils.resolve(httpget.getURI(), target, redirectLocations);\n        System.out.println(\"Final HTTP location: \" + location.toASCIIString());\n        \/\/ \u4e00\u822c\u4f1a\u53d6\u5f97\u4e00\u4e2a\u7edd\u5bf9\u8def\u5f84\u7684uri\n    } finally {\n        response.close();\n    }\n<\/code><\/pre>\n","protected":false},"excerpt":{"rendered":"<p>1.1. \u8bf7\u6c42\u6267\u884c HttpClient\u6700\u57fa\u672c\u7684\u529f\u80fd\u5c31\u662f\u6267\u884cHttp\u65b9\u6cd5\u3002\u4e00\u4e2aHttp\u65b9\u6cd5\u7684\u6267\u884c\u6d89\u53ca\u5230\u4e00\u4e2a\u6216\u8005\u591a\u4e2aHttp\u8bf7\u6c42\/Http\u54cd\u5e94\u7684\u4ea4\u4e92\uff0c\u901a\u5e38\u8fd9\u4e2a\u8fc7\u7a0b\u90fd\u4f1a\u81ea\u52a8\u88abHttpClient\u5904\u7406\uff0c\u5bf9\u7528&#46;&#46;&#46;<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"pgc_sgb_lightbox_settings":"","footnotes":""},"categories":[33],"tags":[8,7,5,13],"class_list":["post-773","post","type-post","status-publish","format-standard","hentry","category-coding","tag-java","tag-7","tag-5","tag-13"],"views":50699,"_links":{"self":[{"href":"https:\/\/www.yeetrack.com\/index.php?rest_route=\/wp\/v2\/posts\/773","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.yeetrack.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.yeetrack.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.yeetrack.com\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.yeetrack.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=773"}],"version-history":[{"count":6,"href":"https:\/\/www.yeetrack.com\/index.php?rest_route=\/wp\/v2\/posts\/773\/revisions"}],"predecessor-version":[{"id":781,"href":"https:\/\/www.yeetrack.com\/index.php?rest_route=\/wp\/v2\/posts\/773\/revisions\/781"}],"wp:attachment":[{"href":"https:\/\/www.yeetrack.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=773"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.yeetrack.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=773"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.yeetrack.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=773"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}