问题
I'm relatively new to android development. I'm developing an android application where i'm sending request to web server and parsing json objects. Frequently i'm getting java.net.SocketTimeoutException: Connection timed out exception while communicating with the server. Some times it will work perfectly without any problem.
I know this same question has been asked in SO many times. But still i didn't get any satisfying solution to this problem. I'm posting my logcat and app-server communication code below.
public JSONObject RequestWithHttpUrlConn(String _url, String param){
HttpURLConnection con = null;
URL url;
String response = "";
Scanner inStream = null;
PrintWriter out = null;
try {
url = new URL(_url);
con = (HttpURLConnection) url.openConnection();
con.setDoOutput(true);
con.setRequestMethod("POST");
if(param != null){
con.setFixedLengthStreamingMode(param.getBytes().length);
}
con.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");
out = new PrintWriter(con.getOutputStream());
if(param != null){
out.print(param);
}
out.flush();
out.close();
inStream = new Scanner(con.getInputStream());
while(inStream.hasNextLine()){
response+=(inStream.nextLine());
}
} catch (MalformedURLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} finally{
if(con != null){
con.disconnect();
}if(inStream != null){
inStream.close();
}if(out != null){
out.flush();
out.close();
}
}
}
Logcat:
03-25 10:55:32.613: W/System.err(18868): java.net.SocketTimeoutException: Connection
timed out
03-25 10:55:32.617: W/System.err(18868):at org.apache.harmony.luni.platform.OSNetworkSystem.connect(Native Method)
03-25 10:55:32.617: W/System.err(18868):at dalvik.system.BlockGuard
$WrappedNetworkSystem.connect(BlockGuard.java:357)
03-25 10:55:32.617: W/System.err(18868):at
org.apache.harmony.luni.net.PlainSocketImpl.connect(PlainSocketImpl.java:204)
03-25 10:55:32.617: W/System.err(18868):at
org.apache.harmony.luni.net.PlainSocketImpl.connect(PlainSocketImpl.java:437)
03-25 10:55:32.617: W/System.err(18868):at java.net.Socket.connect(Socket.java:1002)
03-25 10:55:32.621: W/System.err(18868):at
org.apache.harmony.luni.internal.net.www.protocol.http.HttpConnection.<init>
(HttpConnection.java:75)
03-25 10:55:32.621: W/System.err(18868): at
org.apache.harmony.luni.internal.net.www.protocol.http.HttpConnection.<init>
(HttpConnection.java:48)03-25 10:55:32.624: W/System.err(18868):at
org.apache.harmony.luni.internal.net.www.protocol.http.HttpConnection$Address.connect
(HttpConnection.java:322)03-25 10:55:32.624: W/System.err(18868):at
org.apache.harmony.luni.internal.net.www.protocol.http.HttpConnectionPool.get
(HttpConnectionPool.java:89)03-25 10:55:32.628: W/System.err(18868):at
org.apache.harmony.luni.internal.net.www.protocol.http.HttpURLConnectionImpl.getHttpCon
nection(HttpURLConnectionImpl.java:285)
03-25 10:55:32.628: W/System.err(18868):at org.apache.harmony.luni.internal.net.www.protocol.http.HttpURLConnectionImpl.makeConn
ection(HttpURLConnectionImpl.java:267)
03-25 10:55:32.636: W/System.err(18868):at
org.apache.harmony.luni.internal.net.www.protocol.http.HttpURLConnectionImpl.connect
(HttpURLConnectionImpl.java:205)
03-25 10:55:32.636: W/System.err(18868):at
org.apache.harmony.luni.internal.net.www.protocol.http.HttpURLConnectionImpl.getOutputS
tream(HttpURLConnectionImpl.java:614)
03-25 10:55:32.636: W/System.err(18868):at
com.myapp.core.JSONRequest.RequestWithHttpUrlConn(JSONRequest.java:63)
03-25 10:55:32.636: W/System.err(18868): at com.myapp.core.DetailPage
$AsyncRecBooks.doInBackground(AKBookDetailView.java:265)
03-25 10:55:32.640: W/System.err(18868): at com.myapp.core.DetailPage
$AsyncRecBooks.doInBackground(AKBookDetailView.java:1)
03-25 10:55:32.640: W/System.err(18868): at android.os.AsyncTask$2.call
(AsyncTask.java:185)
03-25 10:55:32.640: W/System.err(18868): at java.util.concurrent.FutureTask
$Sync.innerRun(FutureTask.java:306)
03-25 10:55:32.640: W/System.err(18868): at java.util.concurrent.FutureTask.run
(FutureTask.java:138)
03-25 10:55:32.640: W/System.err(18868): at
java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1088)
03-25 10:55:32.648: W/System.err(18868): at
java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:581)
03-25 10:55:32.648: W/System.err(18868): at java.lang.Thread.run(Thread.java:1019)
03-25 10:55:32.652: E/JSON Parser(18868): Error parsing data org.json.JSONException:
End of input at character 0 of
Can anyone help me out to find out a solution for this? Thanks in Advance....
回答1:
I've searched all over the web and after reading lot of docs regarding connection timeout exception, the thing i understood is that, preventing SocketTimeoutException is beyond our limit...One way to effectively handle it is to define a connection timeout and later handle it by using a try catch block.... hope this will help anyone in future who are facing the same issue.
HttpUrlConnection conn = (HttpURLConnection) url.openConnection();
conn.setConnectTimeout(7000); //set the timeout in milliseconds
回答2:
I'm aware this question is a bit old. But since I stumbled on this while doing research, I thought a little addition might be helpful.
As stated the error cannot be solved by the client, since it is a network related issue. However, what you can do is retry connecting a few times. This may work as a workaround until the real issue is fixed.
for (int retries = 0; retries < 3; retries++) {
try {
final HttpClient client = createHttpClientWithDefaultSocketFactory(null, null);
final HttpResponse response = client.execute(get);
final int statusCode = response.getStatusLine().getStatusCode();
if (statusCode != 200) {
throw new IllegalStateException("GET Request on '" + get.getURI().toString() + "' resulted in " + statusCode);
} else {
return response.getEntity();
}
} catch (final java.net.SocketTimeoutException e) {
// connection timed out...let's try again
}
}
Maybe this helps someone.
回答3:
If you are testing the server in localhost your Android device must be connected to the same local network. Then the Server URL used by your APP must include your computer IP Address and not the "localhost" mask.
回答4:
Set This in OkHttpClient.Builder() Object
val httpClient = OkHttpClient.Builder()
httpClient.connectTimeout(5, TimeUnit.MINUTES) // connect timeout
.writeTimeout(5, TimeUnit.MINUTES) // write timeout
.readTimeout(5, TimeUnit.MINUTES) // read timeout
回答5:
I was facing this problem and the solution was to restart my modem (router). I could get connection for my app to internet after that.
I think the library I am using is not managing connections properly because it happeend just few times.
回答6:
I got this same error as I mistakenly changed the order of the statements
OkHttpClient okHttpClient = new OkHttpClient().newBuilder() .connectTimeout(20, TimeUnit.SECONDS).readTimeout(20,TimeUnit.SECONDS).writeTimeout(20, TimeUnit.SECONDS) .build();
After changing the order of writeTimeout and readTimeout, the error resolved. The final code I used is given below:
OkHttpClient okHttpClient = new OkHttpClient.Builder().connectTimeout(60, TimeUnit.SECONDS)
.writeTimeout(60, TimeUnit.SECONDS)
.readTimeout(60, TimeUnit.SECONDS)
.build();
回答7:
public JSONObject RequestWithHttpUrlConn(String _url, String param){
HttpURLConnection con = null;
URL url;
String response = "";
Scanner inStream = null;
PrintWriter out = null;
try {
url = new URL(_url);
con = (HttpURLConnection) url.openConnection();
con.setDoOutput(true);
con.setRequestMethod("POST");
if(param != null){
con.setFixedLengthStreamingMode(param.getBytes().length);
}
con.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");
out = new PrintWriter(con.getOutputStream());
if(param != null){
out.print(param);
}
out.flush();
out.close();
inStream = new Scanner(con.getInputStream());
while(inStream.hasNextLine()){
response+=(inStream.nextLine());
}
} catch (MalformedURLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} finally{
if(con != null){
con.disconnect();
}if(inStream != null){
inStream.close();
}if(out != null){
out.flush();
out.close();
}
}
}
来源：https://stackoverflow.com/questions/15608499/getting-java-net-sockettimeoutexception-connection-timed-out-in-android