android-async-http框架源码分析
async-http使用地址
android-async-http仓库：git clone https://github.com/loopj/android-async-http
源码分析
我们在做网络请求的时候经常通过下面的方式实例化AsyncHttpClient client=new AsyncHttpClient();然后通过系统内置的请求发送请求，通过async内部的请求去做真正的网络请求。
首先得到的是AsyncHttpClient实例，所以从这里入手分析一下：
<code class="language-java hljs has-numbering" style="display: block; padding: 0px; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-radius: 0px; word-wrap: normal; background: transparent;"> <span class="hljs-javadoc" style="color: rgb(136, 0, 0); box-sizing: border-box;">/**
* Creates a new AsyncHttpClient with default constructor arguments values
*/</span>
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-title" style="box-sizing: border-box;">AsyncHttpClient</span>() {
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">this</span>(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">false</span>, <span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">80</span>, <span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">443</span>);
}</code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; top: 0px; left: 0px; margin: 0px; padding: 6px 0px 40px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style: none; text-align: right; background-color: rgb(238, 238, 238);"><li style="box-sizing: border-box; padding: 0px 5px;">1</li><li style="box-sizing: border-box; padding: 0px 5px;">2</li><li style="box-sizing: border-box; padding: 0px 5px;">3</li><li style="box-sizing: border-box; padding: 0px 5px;">4</li><li style="box-sizing: border-box; padding: 0px 5px;">5</li><li style="box-sizing: border-box; padding: 0px 5px;">6</li></ul>
对于默认值设置了HTTP协议的默认端口为80，HTTPS协议的默认端口为443。
在该函数中调用了AsyncHttpClient(SchemeRegistry schemeRegistry)构造函数，而真正的实例化获取逻辑过程就在AsyncHttpClient(SchemeRegistry方法中，如下所示：
schemeRegistry)
<code class="language-java hljs has-numbering" style="display: block; padding: 0px; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-radius: 0px; word-wrap: normal; background: transparent;"><span class="hljs-javadoc" style="color: rgb(136, 0, 0); box-sizing: border-box;">/**
* Creates a new AsyncHttpClient.
*
*<span class="hljs-javadoctag" style="color: rgb(102, 0, 102); box-sizing: border-box;"> @param</span> schemeRegistry SchemeRegistry to be used
*/</span>
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-title" style="box-sizing: border-box;">AsyncHttpClient</span>(SchemeRegistry schemeRegistry) {
BasicHttpParams httpParams = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> BasicHttpParams();
ConnManagerParams.setTimeout(httpParams, connectTimeout);
ConnManagerParams.setMaxConnectionsPerRoute(httpParams, <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> ConnPerRouteBean(maxConnections));
ConnManagerParams.setMaxTotalConnections(httpParams, DEFAULT_MAX_CONNECTIONS);
HttpConnectionParams.setSoTimeout(httpParams, responseTimeout);
HttpConnectionParams.setConnectionTimeout(httpParams, connectTimeout);
HttpConnectionParams.setTcpNoDelay(httpParams, <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">true</span>);
HttpConnectionParams.setSocketBufferSize(httpParams, DEFAULT_SOCKET_BUFFER_SIZE);
HttpProtocolParams.setVersion(httpParams, HttpVersion.HTTP_1_1);
ClientConnectionManager cm = createConnectionManager(schemeRegistry, httpParams);
Utils.asserts(cm != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>, <span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"Custom implementation of #createConnectionManager(SchemeRegistry, BasicHttpParams) returned null"</span>);
threadPool = getDefaultThreadPool();
requestMap = Collections.synchronizedMap(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> WeakHashMap<Context, List<RequestHandle>>());
clientHeaderMap = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> HashMap<String, String>();
httpContext = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> SyncBasicHttpContext(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> BasicHttpContext());
httpClient = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> DefaultHttpClient(cm, httpParams);
httpClient.addRequestInterceptor(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> HttpRequestInterceptor() {
<span class="hljs-annotation" style="color: rgb(155, 133, 157); box-sizing: border-box;">@Override</span>
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">process</span>(HttpRequest request, HttpContext context) {
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (!request.containsHeader(HEADER_ACCEPT_ENCODING)) {
request.addHeader(HEADER_ACCEPT_ENCODING, ENCODING_GZIP);
}
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">for</span> (String header : clientHeaderMap.keySet()) {
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (request.containsHeader(header)) {
Header overwritten = request.getFirstHeader(header);
Log.d(LOG_TAG,
String.format(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"Headers were overwritten! (%s | %s) overwrites (%s | %s)"</span>,
header, clientHeaderMap.get(header),
overwritten.getName(), overwritten.getValue())
);
<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//remove the overwritten header</span>
request.removeHeader(overwritten);
}
request.addHeader(header, clientHeaderMap.get(header));
}
}
});
httpClient.addResponseInterceptor(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> HttpResponseInterceptor() {
<span class="hljs-annotation" style="color: rgb(155, 133, 157); box-sizing: border-box;">@Override</span>
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">process</span>(HttpResponse response, HttpContext context) {
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">final</span> HttpEntity entity = response.getEntity();
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (entity == <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) {
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span>;
}
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">final</span> Header encoding = entity.getContentEncoding();
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (encoding != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) {
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">for</span> (HeaderElement element : encoding.getElements()) {
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (element.getName().equalsIgnoreCase(ENCODING_GZIP)) {
response.setEntity(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> InflatingEntity(entity));
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">break</span>;
}
}
}
}
});
httpClient.addRequestInterceptor(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> HttpRequestInterceptor() {
<span class="hljs-annotation" style="color: rgb(155, 133, 157); box-sizing: border-box;">@Override</span>
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">process</span>(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">final</span> HttpRequest request, <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">final</span> HttpContext context) <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">throws</span> HttpException, IOException {
AuthState authState = (AuthState) context.getAttribute(ClientContext.TARGET_AUTH_STATE);
CredentialsProvider credsProvider = (CredentialsProvider) context.getAttribute(
ClientContext.CREDS_PROVIDER);
HttpHost targetHost = (HttpHost) context.getAttribute(ExecutionContext.HTTP_TARGET_HOST);
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (authState.getAuthScheme() == <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) {
AuthScope authScope = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> AuthScope(targetHost.getHostName(), targetHost.getPort());
Credentials creds = credsProvider.getCredentials(authScope);
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (creds != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) {
authState.setAuthScheme(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> BasicScheme());
authState.setCredentials(creds);
}
}
}
}, <span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>);
httpClient.setHttpRequestRetryHandler(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> RetryHandler(DEFAULT_MAX_RETRIES, DEFAULT_RETRY_SLEEP_TIME_MILLIS));
}</code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; top: 0px; left: 0px; margin: 0px; padding: 6px 0px 40px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style: none; text-align: right; background-color: rgb(238, 238, 238);"><li style="box-sizing: border-box; padding: 0px 5px;">1</li><li style="box-sizing: border-box; padding: 0px 5px;">2</li><li style="box-sizing: border-box; padding: 0px 5px;">3</li><li style="box-sizing: border-box; padding: 0px 5px;">4</li><li style="box-sizing: border-box; padding: 0px 5px;">5</li><li style="box-sizing: border-box; padding: 0px 5px;">6</li><li style="box-sizing: border-box; padding: 0px 5px;">7</li><li style="box-sizing: border-box; padding: 0px 5px;">8</li><li style="box-sizing: border-box; padding: 0px 5px;">9</li><li style="box-sizing: border-box; padding: 0px 5px;">10</li><li style="box-sizing: border-box; padding: 0px 5px;">11</li><li style="box-sizing: border-box; padding: 0px 5px;">12</li><li style="box-sizing: border-box; padding: 0px 5px;">13</li><li style="box-sizing: border-box; padding: 0px 5px;">14</li><li style="box-sizing: border-box; padding: 0px 5px;">15</li><li style="box-sizing: border-box; padding: 0px 5px;">16</li><li style="box-sizing: border-box; padding: 0px 5px;">17</li><li style="box-sizing: border-box; padding: 0px 5px;">18</li><li style="box-sizing: border-box; padding: 0px 5px;">19</li><li style="box-sizing: border-box; padding: 0px 5px;">20</li><li style="box-sizing: border-box; padding: 0px 5px;">21</li><li style="box-sizing: border-box; padding: 0px 5px;">22</li><li style="box-sizing: border-box; padding: 0px 5px;">23</li><li style="box-sizing: border-box; padding: 0px 5px;">24</li><li style="box-sizing: border-box; padding: 0px 5px;">25</li><li style="box-sizing: border-box; padding: 0px 5px;">26</li><li style="box-sizing: border-box; padding: 0px 5px;">27</li><li style="box-sizing: border-box; padding: 0px 5px;">28</li><li style="box-sizing: border-box; padding: 0px 5px;">29</li><li style="box-sizing: border-box; padding: 0px 5px;">30</li><li style="box-sizing: border-box; padding: 0px 5px;">31</li><li style="box-sizing: border-box; padding: 0px 5px;">32</li><li style="box-sizing: border-box; padding: 0px 5px;">33</li><li style="box-sizing: border-box; padding: 0px 5px;">34</li><li style="box-sizing: border-box; padding: 0px 5px;">35</li><li style="box-sizing: border-box; padding: 0px 5px;">36</li><li style="box-sizing: border-box; padding: 0px 5px;">37</li><li style="box-sizing: border-box; padding: 0px 5px;">38</li><li style="box-sizing: border-box; padding: 0px 5px;">39</li><li style="box-sizing: border-box; padding: 0px 5px;">40</li><li style="box-sizing: border-box; padding: 0px 5px;">41</li><li style="box-sizing: border-box; padding: 0px 5px;">42</li><li style="box-sizing: border-box; padding: 0px 5px;">43</li><li style="box-sizing: border-box; padding: 0px 5px;">44</li><li style="box-sizing: border-box; padding: 0px 5px;">45</li><li style="box-sizing: border-box; padding: 0px 5px;">46</li><li style="box-sizing: border-box; padding: 0px 5px;">47</li><li style="box-sizing: border-box; padding: 0px 5px;">48</li><li style="box-sizing: border-box; padding: 0px 5px;">49</li><li style="box-sizing: border-box; padding: 0px 5px;">50</li><li style="box-sizing: border-box; padding: 0px 5px;">51</li><li style="box-sizing: border-box; padding: 0px 5px;">52</li><li style="box-sizing: border-box; padding: 0px 5px;">53</li><li style="box-sizing: border-box; padding: 0px 5px;">54</li><li style="box-sizing: border-box; padding: 0px 5px;">55</li><li style="box-sizing: border-box; padding: 0px 5px;">56</li><li style="box-sizing: border-box; padding: 0px 5px;">57</li><li style="box-sizing: border-box; padding: 0px 5px;">58</li><li style="box-sizing: border-box; padding: 0px 5px;">59</li><li style="box-sizing: border-box; padding: 0px 5px;">60</li><li style="box-sizing: border-box; padding: 0px 5px;">61</li><li style="box-sizing: border-box; padding: 0px 5px;">62</li><li style="box-sizing: border-box; padding: 0px 5px;">63</li><li style="box-sizing: border-box; padding: 0px 5px;">64</li><li style="box-sizing: border-box; padding: 0px 5px;">65</li><li style="box-sizing: border-box; padding: 0px 5px;">66</li><li style="box-sizing: border-box; padding: 0px 5px;">67</li><li style="box-sizing: border-box; padding: 0px 5px;">68</li><li style="box-sizing: border-box; padding: 0px 5px;">69</li><li style="box-sizing: border-box; padding: 0px 5px;">70</li><li style="box-sizing: border-box; padding: 0px 5px;">71</li><li style="box-sizing: border-box; padding: 0px 5px;">72</li><li style="box-sizing: border-box; padding: 0px 5px;">73</li><li style="box-sizing: border-box; padding: 0px 5px;">74</li><li style="box-sizing: border-box; padding: 0px 5px;">75</li><li style="box-sizing: border-box; padding: 0px 5px;">76</li><li style="box-sizing: border-box; padding: 0px 5px;">77</li><li style="box-sizing: border-box; padding: 0px 5px;">78</li><li style="box-sizing: border-box; padding: 0px 5px;">79</li><li style="box-sizing: border-box; padding: 0px 5px;">80</li><li style="box-sizing: border-box; padding: 0px 5px;">81</li><li style="box-sizing: border-box; padding: 0px 5px;">82</li><li style="box-sizing: border-box; padding: 0px 5px;">83</li><li style="box-sizing: border-box; padding: 0px 5px;">84</li><li style="box-sizing: border-box; padding: 0px 5px;">85</li><li style="box-sizing: border-box; padding: 0px 5px;">86</li><li style="box-sizing: border-box; padding: 0px 5px;">87</li><li style="box-sizing: border-box; padding: 0px 5px;">88</li><li style="box-sizing: border-box; padding: 0px 5px;">89</li><li style="box-sizing: border-box; padding: 0px 5px;">90</li><li style="box-sizing: border-box; padding: 0px 5px;">91</li><li style="box-sizing: border-box; padding: 0px 5px;">92</li></ul>
从代码的最顶层分析，构造参数传入的是SchemeRegistry对象，查看源码这是一个静态的方法，主要存储一些协议的东西
public SchemeRegistry() {
super();
registeredSchemes = new ConcurrentHashMap<String,Scheme>();
}
上面的代码我们主要关注下addResponseInterceptor和addResponseInterceptor，此两个方法主要将我们的请求头和请求的实体加到HttpRequest队列中，对android1.5之前的熟悉的朋友都知道，在最早之前没有流行这些第三方之前我们就是通过HttpRequest来请求的，这等同于j2ee的HttpServletRequest.
接下来我们调运的就是AsyncHttpClient里面的各种get、post、delete等方法，通过看代码可以发现它们最终调用的都是sendRequest方法，如下：
<code class="language-java hljs has-numbering" style="display: block; padding: 0px; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-radius: 0px; word-wrap: normal; background: transparent;"> <span class="hljs-javadoc" style="color: rgb(136, 0, 0); box-sizing: border-box;">/**
* Puts a new request in queue as a new thread in pool to be executed
*
*<span class="hljs-javadoctag" style="color: rgb(102, 0, 102); box-sizing: border-box;"> @param</span> client HttpClient to be used for request, can differ in single requests
*<span class="hljs-javadoctag" style="color: rgb(102, 0, 102); box-sizing: border-box;"> @param</span> contentType MIME body type, for POST and PUT requests, may be null
*<span class="hljs-javadoctag" style="color: rgb(102, 0, 102); box-sizing: border-box;"> @param</span> context Context of Android application, to hold the reference of request
*<span class="hljs-javadoctag" style="color: rgb(102, 0, 102); box-sizing: border-box;"> @param</span> httpContext HttpContext in which the request will be executed
*<span class="hljs-javadoctag" style="color: rgb(102, 0, 102); box-sizing: border-box;"> @param</span> responseHandler ResponseHandler or its subclass to put the response into
*<span class="hljs-javadoctag" style="color: rgb(102, 0, 102); box-sizing: border-box;"> @param</span> uriRequest instance of HttpUriRequest, which means it must be of HttpDelete,
* HttpPost, HttpGet, HttpPut, etc.
*<span class="hljs-javadoctag" style="color: rgb(102, 0, 102); box-sizing: border-box;"> @return</span> RequestHandle of future request process
*/</span>
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">protected</span> RequestHandle <span class="hljs-title" style="box-sizing: border-box;">sendRequest</span>(DefaultHttpClient client, HttpContext httpContext, HttpUriRequest uriRequest, String contentType, ResponseHandlerInterface responseHandler, Context context) {
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (uriRequest == <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) {
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">throw</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> IllegalArgumentException(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"HttpUriRequest must not be null"</span>);
}
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (responseHandler == <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) {
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">throw</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> IllegalArgumentException(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"ResponseHandler must not be null"</span>);
}
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (responseHandler.getUseSynchronousMode() && !responseHandler.getUsePoolThread()) {
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">throw</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> IllegalArgumentException(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"Synchronous ResponseHandler used in AsyncHttpClient. You should create your response handler in a looper thread or use SyncHttpClient instead."</span>);
}
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (contentType != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) {
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (uriRequest <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">instanceof</span> HttpEntityEnclosingRequestBase && ((HttpEntityEnclosingRequestBase) uriRequest).getEntity() != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) {
Log.w(LOG_TAG, <span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"Passed contentType will be ignored because HttpEntity sets content type"</span>);
} <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">else</span> {
uriRequest.setHeader(HEADER_CONTENT_TYPE, contentType);
}
}
responseHandler.setRequestHeaders(uriRequest.getAllHeaders());
responseHandler.setRequestURI(uriRequest.getURI());
AsyncHttpRequest request = newAsyncHttpRequest(client, httpContext, uriRequest, contentType, responseHandler, context);
threadPool.submit(request);
RequestHandle requestHandle = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> RequestHandle(request);
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (context != <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) {
<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// Add request to request map</span>
List<RequestHandle> requestList = requestMap.get(context);
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">synchronized</span> (requestMap) {
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (requestList == <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">null</span>) {
requestList = Collections.synchronizedList(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> LinkedList<RequestHandle>());
requestMap.put(context, requestList);
}
}
requestList.add(requestHandle);
Iterator<RequestHandle> iterator = requestList.iterator();
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">while</span> (iterator.hasNext()) {
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (iterator.next().shouldBeGarbageCollected()) {
iterator.remove();
}
}
}
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> requestHandle;
}</code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; top: 0px; left: 0px; margin: 0px; padding: 6px 0px 40px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style: none; text-align: right; background-color: rgb(238, 238, 238);"><li style="box-sizing: border-box; padding: 0px 5px;">1</li><li style="box-sizing: border-box; padding: 0px 5px;">2</li><li style="box-sizing: border-box; padding: 0px 5px;">3</li><li style="box-sizing: border-box; padding: 0px 5px;">4</li><li style="box-sizing: border-box; padding: 0px 5px;">5</li><li style="box-sizing: border-box; padding: 0px 5px;">6</li><li style="box-sizing: border-box; padding: 0px 5px;">7</li><li style="box-sizing: border-box; padding: 0px 5px;">8</li><li style="box-sizing: border-box; padding: 0px 5px;">9</li><li style="box-sizing: border-box; padding: 0px 5px;">10</li><li style="box-sizing: border-box; padding: 0px 5px;">11</li><li style="box-sizing: border-box; padding: 0px 5px;">12</li><li style="box-sizing: border-box; padding: 0px 5px;">13</li><li style="box-sizing: border-box; padding: 0px 5px;">14</li><li style="box-sizing: border-box; padding: 0px 5px;">15</li><li style="box-sizing: border-box; padding: 0px 5px;">16</li><li style="box-sizing: border-box; padding: 0px 5px;">17</li><li style="box-sizing: border-box; padding: 0px 5px;">18</li><li style="box-sizing: border-box; padding: 0px 5px;">19</li><li style="box-sizing: border-box; padding: 0px 5px;">20</li><li style="box-sizing: border-box; padding: 0px 5px;">21</li><li style="box-sizing: border-box; padding: 0px 5px;">22</li><li style="box-sizing: border-box; padding: 0px 5px;">23</li><li style="box-sizing: border-box; padding: 0px 5px;">24</li><li style="box-sizing: border-box; padding: 0px 5px;">25</li><li style="box-sizing: border-box; padding: 0px 5px;">26</li><li style="box-sizing: border-box; padding: 0px 5px;">27</li><li style="box-sizing: border-box; padding: 0px 5px;">28</li><li style="box-sizing: border-box; padding: 0px 5px;">29</li><li style="box-sizing: border-box; padding: 0px 5px;">30</li><li style="box-sizing: border-box; padding: 0px 5px;">31</li><li style="box-sizing: border-box; padding: 0px 5px;">32</li><li style="box-sizing: border-box; padding: 0px 5px;">33</li><li style="box-sizing: border-box; padding: 0px 5px;">34</li><li style="box-sizing: border-box; padding: 0px 5px;">35</li><li style="box-sizing: border-box; padding: 0px 5px;">36</li><li style="box-sizing: border-box; padding: 0px 5px;">37</li><li style="box-sizing: border-box; padding: 0px 5px;">38</li><li style="box-sizing: border-box; padding: 0px 5px;">39</li><li style="box-sizing: border-box; padding: 0px 5px;">40</li><li style="box-sizing: border-box; padding: 0px 5px;">41</li><li style="box-sizing: border-box; padding: 0px 5px;">42</li><li style="box-sizing: border-box; padding: 0px 5px;">43</li><li style="box-sizing: border-box; padding: 0px 5px;">44</li><li style="box-sizing: border-box; padding: 0px 5px;">45</li><li style="box-sizing: border-box; padding: 0px 5px;">46</li><li style="box-sizing: border-box; padding: 0px 5px;">47</li><li style="box-sizing: border-box; padding: 0px 5px;">48</li><li style="box-sizing: border-box; padding: 0px 5px;">49</li><li style="box-sizing: border-box; padding: 0px 5px;">50</li><li style="box-sizing: border-box; padding: 0px 5px;">51</li><li style="box-sizing: border-box; padding: 0px 5px;">52</li><li style="box-sizing: border-box; padding: 0px 5px;">53</li><li style="box-sizing: border-box; padding: 0px 5px;">54</li><li style="box-sizing: border-box; padding: 0px 5px;">55</li><li style="box-sizing: border-box; padding: 0px 5px;">56</li><li style="box-sizing: border-box; padding: 0px 5px;">57</li><li style="box-sizing: border-box; padding: 0px 5px;">58</li><li style="box-sizing: border-box; padding: 0px 5px;">59</li><li style="box-sizing: border-box; padding: 0px 5px;">60</li><li style="box-sizing: border-box; padding: 0px 5px;">61</li><li style="box-sizing: border-box; padding: 0px 5px;">62</li></ul>
这个方法的主要作用是将一个新的请求添加到队列线程池中执行。
调用本方法，主要实现AsyncHttpRequest request = newAsyncHttpRequest(client, httpContext, uriRequest,contentType, responseHandler,这行开始是主要的逻辑，其创建了请求，接着通过
context);threadPool.submit(request);把请求提交到线程池，接着通过RequestHandle把请求包装到RequestHandle用于之后的取消、管理等操作。然后坐等现在池的我们请求的这个线程去执行，等待返回结果。
requestHandle = new RequestHandle(request);
总结一下：
AsyncHttpClient 核心类，使用HttpClient执行网络请求，提供了get，put，post，delete，head等请求方法，使用起来很简单，只需以url及RequestParams调用相应的方法即可，还可以选择性地传入Context，用于取消Content相关的请求，同时必须提供ResponseHandlerInterface（AsyncHttpResponseHandler继承自ResponseHandlerInterface）的实现类，一般为AsyncHttpResponseHandler的子类，AsyncHttpClient内部有一个线程池，当使用AsyncHttpClient执行网络请求时，最终都会调用sendRequest方法，在这个方法内部将请求参数封装成AsyncHttpRequest（继承自Runnable）交由内部的线程池执行。
SyncHttpClient 继承自AsyncHttpClient，同步执行网络请求，AsyncHttpClient把请求封装成AsyncHttpRequest后提交至线程池，SyncHttpClient把请求封装成AsyncHttpRequest后直接调用它的run方法。
AsyncHttpRequest 继承自Runnabler，被submit至线程池执行网络请求并发送start，success等消息。
AsyncHttpResponseHandler 接收请求结果，一般重写onSuccess及onFailure接收请求成功或失败的消息，还有onStart，onFinish等消息。
TextHttpResponseHandler、JsonHttpResponseHandler、BaseJsonHttpResponseHandler这些类都继承自AsyncHttpResponseHandler，只是重写了AsyncHttpResponseHandler的onSuccess和onFailure方法，将请求结果进行了转换而已。
RequestParams 请求参数，可以添加普通的字符串参数，并可添加File，InputStream上传文件。
android-async-http框架源码分析的更多相关文章
- Android Small插件化框架源码分析
Android Small插件化框架源码分析 目录 概述 Small如何使用 插件加载流程 待改进的地方 一.概述 Small是一个写得非常简洁的插件化框架,工程源码位置:https://github ...
- 介绍开源的.net通信框架NetworkComms框架 源码分析
原文网址: http://www.cnblogs.com/csdev Networkcomms 是一款C# 语言编写的TCP/UDP通信框架 作者是英国人 以前是收费的 售价249英镑 我曾经花了 ...
- YII框架源码分析(百度PHP大牛创作-原版-无广告无水印)
YII 框架源码分析 百度联盟事业部——黄银锋 目 录 1. 引言 3 1.1.Yii 简介 3 1.2.本文内容与结构 3 2.组件化与模块化 4 2.1.框架加载和运行流程 4 ...
- Spark RPC框架源码分析（一）简述
Spark RPC系列: Spark RPC框架源码分析(一)运行时序 Spark RPC框架源码分析(二)运行时序 Spark RPC框架源码分析(三)运行时序 一. Spark rpc框架概述 S ...
- Spark RPC框架源码分析（二）RPC运行时序
前情提要: Spark RPC框架源码分析(一)简述 一. Spark RPC概述 上一篇我们已经说明了Spark RPC框架的一个简单例子,Spark RPC相关的两个编程模型,Actor模型和Re ...
- Spark RPC框架源码分析（三）Spark心跳机制分析
一.Spark心跳概述 前面两节中介绍了Spark RPC的基本知识,以及深入剖析了Spark RPC中一些源码的实现流程. 具体可以看这里: Spark RPC框架源码分析(二)运行时序 Spark ...
- nodejs的Express框架源码分析、工作流程分析
nodejs的Express框架源码分析.工作流程分析 1.Express的编写流程 2.Express关键api的使用及其作用分析 app.use(middleware); connect pack ...
- Android事件分发机制源码分析
Android事件分发机制源码分析 Android事件分发机制源码分析 Part1事件来源以及传递顺序 Activity分发事件源码 PhoneWindow分发事件源码 小结 Part2ViewGro ...
- laravel框架源码分析（一）自动加载
一.前言 使用php已有好几年,laravel的使用也是有好长时间,但是一直对于框架源码的理解不深,原因很多,归根到底还是php基础不扎实,所以源码看起来也比较吃力.最近有时间,所以开启第5.6遍的框 ...
- iOS常用框架源码分析
SDWebImage NSCache 类似可变字典,线程安全,使用可变字典自定义实现缓存时需要考虑加锁和释放锁 在内存不足时NSCache会自动释放存储的对象,不需要手动干预 NSCache的key不 ...
随机推荐
- SSL协议相关证书文件
密钥: 我理解是公钥+私钥的统称. 密钥对: 公钥(证书)和私钥成对存在.通信双方各持有自己的私钥和对方的公钥.自己的私钥需密切保护,而公钥是公开给对方的.在windows下,单独存在的公钥一般是后缀 ...
- JAVA面向对象-----super关键字
JAVA面向对象-–super关键字 1:定义Father(父类)类 1:成员变量int x=1; 2:构造方法无参的和有参的,有输出语句 2:定义Son类extends Father类 1:成员变量 ...
- Linux系统编程-----进程fork()
在开始之前,我们先来了解一些基本的概念: 1. 程序, 没有在运行的可执行文件 进程, 运行中的程序 2. 进程调度的方法: 按时间片轮转 先来先服务 短时间优先 按优先级别 3. 进程的状态: 就绪 ...
- Hibernate单表操作
单一主键 assigned:由Java应用程序负责生成(即手工的赋值) native:由底层的数据库自动的生成标示符,如果是MySQL就是auto_increment,如果是Oracle就是seque ...
- 最简单的基于libVLC的例子：最简单的基于libVLC的视频播放器（图形界面版）
===================================================== 最简单的基于libVLC的例子文章列表: 最简单的基于libVLC的例子:最简单的基于lib ...
- 最简单的视频编码器：基于libvpx（编码YUV为VP8）
===================================================== 最简单的视频编码器系列文章列表: 最简单的视频编码器:编译 最简单的视频编码器:基于libx ...
- iOS中 支付宝钱包详解/第三方支付 韩俊强的博客
每日更新关注:http://weibo.com/hanjunqiang 新浪微博! iOS开发者交流QQ群: 446310206 一.在app中成功完成支付宝支付的过程 1.申请支付宝钱包.参考网址 ...
- UNIX网络编程——I/O复用：select和poll函数
我们看到TCP客户同时处理两个输入:标准输入和TCP套接字.我们遇到的问题是就在客户阻塞于(标准输入上)fgets调用,服务器进程会被杀死.服务器TCP虽然正确的给客户TCP发送了一个FIN,但是既然 ...
- 深入浅出EF之ModelFirst和DBFirst
在上篇博文中,小编主要简单的介绍了一下EF的一些基础知识,其中,小编蜻蜓点水的提了一下ModelFirst和DBFirst,ModelFirst先设计实体,然后根据模型生成数据库,DBFirst根据数 ...
- Http协议处理器——Http11Processor
Http11Processor组件提供了对Http协议通信的处理,包括对套接字的读取过滤.对http协议的解析并封装成请求对象.http响应对象的生成.套接字的过滤写入等等操作. 喜欢研究java的同 ...