在HttpClient 4.5中使用HTTPClientParams

HttpClient httpClient = new DefaultHttpClient();
HttpParams params = httpClient.getParams();

// 设置连接超时时间为10秒
HttpConnectionParams.setConnectionTimeout(params, 10000);

// 设置读取超时时间为30秒
HttpConnectionParams.setSoTimeout(params, 30000);

// 设置最大连接数为100
ConnManagerParams.setMaxTotalConnections(params, 100);

// 设置每个路由的最大连接数为20
ConnManagerParams.setMaxConnectionsPerRoute(params, new ConnPerRouteBean(20));

// 设置重试次数为3
HttpClientParams.setRetryCount(params, 3);

// 设置代理服务器
HttpHost proxy = new HttpHost("proxy.example.com", 8080);
params.setParameter(ConnRoutePNames.DEFAULT_PROXY, proxy);

// 设置用户代理
params.setParameter(CoreProtocolPNames.USER_AGENT, "MyHttpClient/1.0");

// 设置编码
params.setParameter(CoreProtocolPNames.HTTP_CONTENT_CHARSET, "UTF-8");

// 设置SSL/TLS设置
SchemeRegistry schemeRegistry = new SchemeRegistry();
schemeRegistry.register(new Scheme("https", SSLSocketFactory.getSocketFactory(), 443));
ClientConnectionManager cm = new ThreadSafeClientConnManager(params, schemeRegistry);
httpClient = new DefaultHttpClient(cm, params);