我编写了一个程序,通过随机代理打开一个网站的httpurlconnection。我的httpurlconnection被称为conn。现在我知道,有些代理可能太慢了,所以我使用conn.setConnectTimeout(40000)
和conn.setReadTimeout(40000)
将连接的超时时间设置为40000毫秒。
这样做之后,我得到了这段代码:
long diff = 0;
long starttime = 0;
long endtime = 0;
try
{
starttime = System.currentTimeMillis();
conn.connect();
endtime = System.currentTimeMillis();
diff = endtime - starttime;
if (endtime <= starttime + conn.getConnectTimeout())
{
//Trying to read sourecode
InputStreamReader isrConn = new InputStreamReader(conn.getInputStream());
BufferedReader brConn = new BufferedReader(isrConn);
line = brConn.readLine();
while (line != null)
{
response += line + "\t";
try
{
line = brConn.readLine();
} catch (IOException e)
{
printError("Reading sourcecode failed.");
}
}
}
else
{
response = "blabla.";
}
// If conn.connect failed
} catch (IOException e)
{
endtime = System.currentTimeMillis();
diff = endtime - starttime;
response = "Message: "+e.getMessage() +" MyTimeout:"+ conn.getConnectTimeout() +" Actual time passed: "+ diff;
e.printStackTrace();
}
有很多原因可能导致连接失败,所以在许多情况下,我会进入最后的catch块并得到以下输出:
Message: Connection timed out: connect MyTimeout:40000 Actual time passed: 21012
Message: Connection timed out: connect MyTimeout:40000 Actual time passed: 21016
Message: Connection timed out: connect MyTimeout:40000 Actual time passed: 21010
Message: Connection timed out: connect MyTimeout:40000 Actual time passed: 21009
所以我的问题是:我已将超时设置为40000毫秒,但在约21000毫秒后我收到了“连接超时”的响应,请问您知道这是为什么吗?
编辑:我正在使用Windows 7,并且现在根据评论中的建议在catch块中添加了e.printStackTrace()。谢谢到目前为止提供的帮助。现在的输出结果如下(示例):
java.net.ConnectException: Connection timed out: connect
at java.net.DualStackPlainSocketImpl.waitForConnect(Native Method)
at java.net.DualStackPlainSocketImpl.socketConnect(Unknown Source)
at java.net.AbstractPlainSocketImpl.doConnect(Unknown Source)
at java.net.AbstractPlainSocketImpl.connectToAddress(Unknown Source)
at java.net.AbstractPlainSocketImpl.connect(Unknown Source)
at java.net.PlainSocketImpl.connect(Unknown Source)
at java.net.Socket.connect(Unknown Source)
at sun.net.NetworkClient.doConnect(Unknown Source)
at sun.net.www.http.HttpClient.openServer(Unknown Source)
at sun.net.www.http.HttpClient$1.run(Unknown Source)
at sun.net.www.http.HttpClient$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at sun.net.www.http.HttpClient.privilegedOpenServer(Unknown Source)
at sun.net.www.http.HttpClient.openServer(Unknown Source)
at sun.net.www.http.HttpClient.<init>(Unknown Source)
at sun.net.www.http.HttpClient.New(Unknown Source)
at sun.net.www.http.HttpClient.New(Unknown Source)
at sun.net.www.protocol.http.HttpURLConnection.getNewHttpClient(Unknown Source)
at sun.net.www.protocol.http.HttpURLConnection.plainConnect(Unknown Source)
at sun.net.www.protocol.http.HttpURLConnection.connect(Unknown Source)
at TestThread.getSourcePage(TestThread.java:361)
at TestThread.aChecker(TestThread.java:216)
at TestThread.getNextProxy(TestThread.java:169)
at TestThread.getNextC(TestThread.java:157)
at TestThread.aChecker(TestThread.java:273)
at TestThread.getNextProxy(TestThread.java:169)
at TestThread.aChecker(TestThread.java:295)
at TestThread.getNextProxy(TestThread.java:169)
at TestThread.getNextC(TestThread.java:157)
at TestThread.run(TestThread.java:103)
at java.lang.Thread.run(Unknown Source)
Message: Connection timed out: connect MyTimeout:40000 Actual time passed: 21015
e.printStackTrace()
的输出。 - Chris Snow