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Thread locked at BufferedReader.readLine

Madhu Kaparapu
Ranch Hand

Joined: Jul 04, 2005
Posts: 35
Hi Team,

I have a service/thread which reads the xml data from the given RSS XML feed URL and writes to a file. This service got hangs sometime twice in a week and by looking at the jstack process dump it seems a thread lock appears during the RSS xml Feed URL connection for getting XML feed data.

Please see the below jstack information:

"Thread-3" prio=10 tid=0x08264400 nid=0x207b runnable [0x8bf99000..0x8bf99e20]
java.lang.Thread.State: RUNNABLE
at java.net.SocketInputStream.socketRead0(Native Method)
at java.net.SocketInputStream.read(SocketInputStream.java:129)
at java.io.BufferedInputStream.read1(BufferedInputStream.java:256)
at java.io.BufferedInputStream.read(BufferedInputStream.java:317)
- locked <0xb1955e28> (a java.io.BufferedInputStream)
at sun.net.www.http.ChunkedInputStream.fastRead(ChunkedInputStream.java:221)
at sun.net.www.http.ChunkedInputStream.read(ChunkedInputStream.java:662)
- locked <0xb1958b00> (a sun.net.www.http.ChunkedInputStream)
at java.io.FilterInputStream.read(FilterInputStream.java:116)
at sun.net.www.protocol.http.HttpURLConnection$HttpInputStream.read(HttpURLConnection.java:2391)
at sun.nio.cs.StreamDecoder.readBytes(StreamDecoder.java:264)
at sun.nio.cs.StreamDecoder.implRead(StreamDecoder.java:306)
at sun.nio.cs.StreamDecoder.read(StreamDecoder.java:158)
- locked <0xb194a228> (a java.io.InputStreamReader)
at java.io.InputStreamReader.read(InputStreamReader.java:167)
at java.io.BufferedReader.fill(BufferedReader.java:136)
at java.io.BufferedReader.readLine(BufferedReader.java:299)
- locked <0xb194a228> (a java.io.InputStreamReader)
at java.io.BufferedReader.readLine(BufferedReader.java:362)
at com.xxx.util.XMLResponseReadAndWrite.getResponse(XMLResponseReadAndWrite.java:44)
at com.xxx.AggregationProcess.run(AggregationProcess.java:132)
at java.lang.Thread.run(Thread.java:619)

Each time i have to kill the process manaully... . Please find the attached full jstack dump and help in trouble shooting this issue.

Madhu Kaparapu.
Consider Paul's rocket mass heater.
subject: Thread locked at BufferedReader.readLine
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