commons-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Julián Lastiri (JIRA) <j...@apache.org>
Subject [jira] [Updated] (NET-501) Race Condition on TelnetClient.disconnect() and TelnetInputStream.run() . java.lang.IllegalStateException: Queue is full! Cannot process another character.
Date Thu, 07 Feb 2013 22:13:12 GMT

     [ https://issues.apache.org/jira/browse/NET-501?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]

Julián Lastiri updated NET-501:
-------------------------------

    Description: 
I'm getting the following exception while disconnecting a threaded (readerThread=true) TelnetClient
connection. 

Exception in thread "Thread-160" java.lang.IllegalStateException: Queue is full! Cannot process
another character.
	at org.apache.commons.net.telnet.TelnetInputStream.__processChar(TelnetInputStream.java:339)
	at org.apache.commons.net.telnet.TelnetInputStream.run(TelnetInputStream.java:647)
	at java.lang.Thread.run(Thread.java:722)

I noticed that when TelnetClient.disconnect() is called the attribute __threaded is set to
false while the thread in the TelnetInputStream.run() method could call TelnetInputStream().__processChar(...)
throwing IllegalStateException


This is a test program to reproduce the issue

public class TestTelnetClient implements Runnable {

	/**
	 * @param args
	 */
	public static void main(String[] args) {
		ArrayList<Thread> workers = new ArrayList<Thread>();
		for( int i=0; i<1000; ++i){
			Thread t = new Thread ( new TestTelnetClient() );
			t.start();
			workers.add(t);
		}
		for (Thread t : workers ) {			
			try {
				t.join();			
			} catch (InterruptedException e) {
				e.printStackTrace();
			}
		}			

	}

	@Override
	public void run() {
		System.out.println("Starting thread...");
		TelnetClient tc = new TelnetClient();
//		tc.setReaderThread(false);
		try {
			tc.connect("localhost", 23);
			tc.setSoTimeout(1000);
			InputStream in = tc.getInputStream();
			int ch;
			in.read();
		} catch (SocketException e) {
			e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		} finally {
			System.out.println("Disconnecting...");
			try {
				tc.disconnect();
			} catch (IOException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
		}
		
	}

}

A telnet server (telnetd) is required. I also modified the initial banner ( /etc/issue.net
) with a lot of characters to get a better chance to receive information while calling disconnect.

  was:
I'm getting the following exception while disconnecting a threaded (readerThread=true) TelnetClient
connection. 

Exception in thread "Thread-160" java.lang.IllegalStateException: Queue is full! Cannot process
another character.
	at org.apache.commons.net.telnet.TelnetInputStream.__processChar(TelnetInputStream.java:339)
	at org.apache.commons.net.telnet.TelnetInputStream.run(TelnetInputStream.java:647)
	at java.lang.Thread.run(Thread.java:722)

I noticed that when TelnetClient.disconnect() is called the attribute __threaded is set to
false while the thread in the TelnetInputStream.run() method could call TelnetInputStream().__processChar(...)
throwing IllegalStateException

    
> Race Condition on TelnetClient.disconnect() and TelnetInputStream.run() . java.lang.IllegalStateException:
Queue is full! Cannot process another character.
> -----------------------------------------------------------------------------------------------------------------------------------------------------------
>
>                 Key: NET-501
>                 URL: https://issues.apache.org/jira/browse/NET-501
>             Project: Commons Net
>          Issue Type: Bug
>          Components: Telnet
>    Affects Versions: 3.2
>         Environment: Ubuntu 12.04 64 bits x86
>            Reporter: Julián Lastiri
>
> I'm getting the following exception while disconnecting a threaded (readerThread=true)
TelnetClient connection. 
> Exception in thread "Thread-160" java.lang.IllegalStateException: Queue is full! Cannot
process another character.
> 	at org.apache.commons.net.telnet.TelnetInputStream.__processChar(TelnetInputStream.java:339)
> 	at org.apache.commons.net.telnet.TelnetInputStream.run(TelnetInputStream.java:647)
> 	at java.lang.Thread.run(Thread.java:722)
> I noticed that when TelnetClient.disconnect() is called the attribute __threaded is set
to false while the thread in the TelnetInputStream.run() method could call TelnetInputStream().__processChar(...)
throwing IllegalStateException
> This is a test program to reproduce the issue
> public class TestTelnetClient implements Runnable {
> 	/**
> 	 * @param args
> 	 */
> 	public static void main(String[] args) {
> 		ArrayList<Thread> workers = new ArrayList<Thread>();
> 		for( int i=0; i<1000; ++i){
> 			Thread t = new Thread ( new TestTelnetClient() );
> 			t.start();
> 			workers.add(t);
> 		}
> 		for (Thread t : workers ) {			
> 			try {
> 				t.join();			
> 			} catch (InterruptedException e) {
> 				e.printStackTrace();
> 			}
> 		}			
> 	}
> 	@Override
> 	public void run() {
> 		System.out.println("Starting thread...");
> 		TelnetClient tc = new TelnetClient();
> //		tc.setReaderThread(false);
> 		try {
> 			tc.connect("localhost", 23);
> 			tc.setSoTimeout(1000);
> 			InputStream in = tc.getInputStream();
> 			int ch;
> 			in.read();
> 		} catch (SocketException e) {
> 			e.printStackTrace();
> 		} catch (IOException e) {
> 			e.printStackTrace();
> 		} finally {
> 			System.out.println("Disconnecting...");
> 			try {
> 				tc.disconnect();
> 			} catch (IOException e) {
> 				// TODO Auto-generated catch block
> 				e.printStackTrace();
> 			}
> 		}
> 		
> 	}
> }
> A telnet server (telnetd) is required. I also modified the initial banner ( /etc/issue.net
) with a lot of characters to get a better chance to receive information while calling disconnect.

--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators
For more information on JIRA, see: http://www.atlassian.com/software/jira

Mime
View raw message