Author: ceki Date: Sat Jun 13 17:16:07 2009 New Revision: 2286 Added: logback/trunk/logback-classic/src/test/java/ch/qos/logback/classic/issue/lbclassic133/ logback/trunk/logback-classic/src/test/java/ch/qos/logback/classic/issue/lbclassic133/Accessor.java logback/trunk/logback-classic/src/test/java/ch/qos/logback/classic/issue/lbclassic133/DeadlockTest.java logback/trunk/logback-classic/src/test/java/ch/qos/logback/classic/issue/lbclassic133/Worker.java logback/trunk/logback-classic/src/test/java/ch/qos/logback/classic/issue/lbclassic133/logback-test.xml Log: files associated with LBCLASSIC-133 Added: logback/trunk/logback-classic/src/test/java/ch/qos/logback/classic/issue/lbclassic133/Accessor.java ============================================================================== --- (empty file) +++ logback/trunk/logback-classic/src/test/java/ch/qos/logback/classic/issue/lbclassic133/Accessor.java Sat Jun 13 17:16:07 2009 @@ -0,0 +1,23 @@ +package ch.qos.logback.classic.issue.lbclassic133; + +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + +public class Accessor { + private static Logger s_logger = LoggerFactory.getLogger(Accessor.class); + + public void access(Worker worker) { + /** + * at some point, for any reason, this method decides to log the status of + * the worker object. + */ + s_logger.debug("Current worker status is: {}.", worker); + /** + * the following line would not cause the deadlock, because the thread never + * tries to acquire a lock on worker while already having a lock on the + * logger. + */ + //s_logger.debug("Current worker status (not deadlocking) is: {}.", worker + // .toString()); + } +} Added: logback/trunk/logback-classic/src/test/java/ch/qos/logback/classic/issue/lbclassic133/DeadlockTest.java ============================================================================== --- (empty file) +++ logback/trunk/logback-classic/src/test/java/ch/qos/logback/classic/issue/lbclassic133/DeadlockTest.java Sat Jun 13 17:16:07 2009 @@ -0,0 +1,37 @@ +package ch.qos.logback.classic.issue.lbclassic133; + +import static org.junit.Assert.assertFalse; + +import org.junit.Test; +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + +public class DeadlockTest { + private static Logger s_logger = LoggerFactory.getLogger(DeadlockTest.class); + + @Test + public void deadlockTest() throws Exception { + s_logger.debug("Starting test."); + + final Worker worker = new Worker(); + final Thread workerThread = new Thread(new Runnable() { + public void run() { + worker.work(); + } + }); + workerThread.setName("WorkerThread"); + + final Thread accessorThread = new Thread(new Runnable() { + public void run() { + new Accessor().access(worker); + } + }); + accessorThread.setName("AccessorThread"); + + workerThread.start(); + accessorThread.start(); + + workerThread.join(5 * 1000); + assertFalse("Worker thread seems locked.", workerThread.isAlive()); + } +} Added: logback/trunk/logback-classic/src/test/java/ch/qos/logback/classic/issue/lbclassic133/Worker.java ============================================================================== --- (empty file) +++ logback/trunk/logback-classic/src/test/java/ch/qos/logback/classic/issue/lbclassic133/Worker.java Sat Jun 13 17:16:07 2009 @@ -0,0 +1,40 @@ +package ch.qos.logback.classic.issue.lbclassic133; + +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + +public class Worker { + private static Logger s_logger = LoggerFactory.getLogger(Worker.class); + + private final Object m_lock = new Object(); + + public void work() { + // Locks the object to do some work changing internal status. + synchronized (m_lock) { + // Does some work... + try { + Thread.sleep(1 * 1000); + } catch (InterruptedException exc) { + // + } + // Then calls logger, while still holding the lock. + s_logger.debug("Did some work, result is: {}."/* ,... */); + } + } + + public String getStatus() { + // Locks the object to make sure the status snapshot is coherent. (Will + // deadlock.) + synchronized (m_lock) { + // Packs some status information, e.g. in a StringBuffer. + final StringBuffer buf = new StringBuffer("STATUS"); + // Returns the string. + return buf.toString(); + } + } + + @Override + public String toString() { + return getStatus(); + } +} \ No newline at end of file Added: logback/trunk/logback-classic/src/test/java/ch/qos/logback/classic/issue/lbclassic133/logback-test.xml ============================================================================== --- (empty file) +++ logback/trunk/logback-classic/src/test/java/ch/qos/logback/classic/issue/lbclassic133/logback-test.xml Sat Jun 13 17:16:07 2009 @@ -0,0 +1,16 @@ +<?xml version="1.0" encoding="UTF-8"?> +<configuration> + + <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender"> + <layout class="ch.qos.logback.classic.PatternLayout"> + <param name="Pattern" + value="%relative %level [%thread] %logger{25} %message %nopex\n" /> + </layout> + </appender> + + <root> + <level value="DEBUG" /> + <appender-ref ref="STDOUT" /> + </root> + +</configuration> \ No newline at end of file