java - DefaultHttpClient 超时

Question

我对 DefaultHttpClient 中的超时如何工作感到有点困惑。

我正在使用这段代码:

private DefaultHttpClient createHttpClient() {
        HttpParams my_httpParams = new BasicHttpParams();

        HttpConnectionParams.setConnectionTimeout(my_httpParams, 3000);
        HttpConnectionParams.setSoTimeout(my_httpParams, 15000);

        SchemeRegistry registry = new SchemeRegistry();
        registry.register(new Scheme("http", PlainSocketFactory.getSocketFactory(), 80));
        ThreadSafeClientConnManager multiThreadedConnectionManager = new ThreadSafeClientConnManager(my_httpParams, registry);

        DefaultHttpClient httpclient = new DefaultHttpClient(multiThreadedConnectionManager, my_httpParams);

        return httpclient;
}

.

String url = "http://www.example.com";

DefaultHttpClient httpclient = createHttpClient();
HttpGet httpget = new HttpGet(url);

try {
    HttpResponse response = httpclient.execute(httpget);
    StatusLine statusLine = response.getStatusLine();
    mStatusCode = statusLine.getStatusCode();

    if (mStatusCode == 200){
        content = EntityUtils.toString(response.getEntity());
    }

} catch (ClientProtocolException e) {
    e.printStackTrace();
} catch (IOException e) {
    e.printStackTrace();
} catch (IllegalStateException e){
    e.printStackTrace();
}

当过了 15 秒，还没有收到所有数据时，就会抛出异常，对吧？但是用哪种方法呢？我认为它是 .execute(httpget) 方法，但那个方法只告诉我它抛出 ClientProtocolException 和 IOException。谁能帮我澄清一下？

Answer 1

它确实在 execute() 上抛出异常。 SocketTimeoutException 的父类是一个 IOException。处理 IOException 的 catch block 将能够捕获两者。

尝试执行这段代码。

HttpParams my_httpParams = new BasicHttpParams();
HttpConnectionParams.setConnectionTimeout(my_httpParams, 3000);
HttpConnectionParams.setSoTimeout(my_httpParams, 1);
DefaultHttpClient defaultHttpClient = new DefaultHttpClient(my_httpParams);
HttpGet httpGet = new HttpGet("http://google.com");
defaultHttpClient.execute(httpGet);

它导致了这个异常。

java.net.SocketTimeoutException: Read timed out
    at java.net.SocketInputStream.socketRead0(Native Method)
    at java.net.SocketInputStream.read(Unknown Source)
    ...
    at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:805)
    at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:784)

您始终可以选择有选择地处理异常，方法是捕获异常并稍后处理 IOException。

try
{
    // Your code
}
catch (SocketTimeoutException e)
{
    // handle timeouts
    e.printStackTrace();
}
catch (IOException e)
{
    // handle other IO exceptions
    e.printStackTrace();
}