org.apache.derbyTesting.functionTests.tests.lang

Class DeadlockModeTest

java.lang.Object

junit.framework.Assert

junit.framework.TestCase

org.apache.derbyTesting.junit.BaseTestCase

org.apache.derbyTesting.junit.BaseJDBCTestCase

org.apache.derbyTesting.functionTests.tests.lang.DeadlockModeTest

All Implemented Interfaces:

junit.framework.Test

public class DeadlockModeTest
extends BaseJDBCTestCase

This tests for deadlock which can occur if two threads get a row lock before getting a table lock on the same table. This can happen if the lock obtained by the insert, update or delete result set is a smaller range than the table scan result set. The insert, update or delete result set lock is obtained first. For example, if the insert, update or delete result set obtain a row lock and then the table scan obtains a table scan lock, deadlock can occur since two threads can obtain the row lock and then both thread will want the same table lock.

Field Summary

Fields

Modifier and Type	Field and Description
private java.util.LinkedList	listExceptions
private int	startedCount
private java.lang.Object	syncObject
private static int	THREAD_COUNT

Fields inherited from class org.apache.derbyTesting.junit.BaseTestCase

DEFAULT_DB_DIR, DERBY_LOG, ERRORSTACKTRACEFILE

Constructor Summary

Constructors

Constructor and Description
DeadlockModeTest(java.lang.String name) Creates a new instance of DeadlockModeTest

Method Summary

Modifier and Type	Method and Description
protected static junit.framework.Test	baseSuite(java.lang.String name)
private void	createThreads(java.lang.Thread[] t) This method creates THREAD_COUNT threads which will all try to update the same table
static junit.framework.Test	suite()
void	testThreadsUpdatingTable() Tests for a deadlock on concurrent accesses to the database
private void	threadWorker(java.sql.Connection threadConnection) This method has the code that each thread will be running.
private void	waitForThreads(java.lang.Thread[] t) This method waits for the threads to finish their execution.

Methods inherited from class org.apache.derbyTesting.junit.BaseJDBCTestCase

assertCallError, assertCheckTable, assertCompileError, assertEquals, assertEquals, assertEquals, assertEquivalentDataType, assertErrorCode, assertGetIntError, assertNextError, assertPreparedStatementError, assertSQLExceptionEquals, assertSQLState, assertSQLState, assertStatementError, assertStatementError, assertStatementError, assertStatementError, assertStatementErrorUnordered, assertTableRowCount, assertUpdateCount, assertUpdateCount, assertWarning, checkAllConsistency, checkEstimatedRowCount, closeStatement, commit, createStatement, createStatement, createStatement, dropTable, dropTable, dropView, dropView, emptyStatementCache, getClientTransactionID, getConnection, getDatabaseProperty, getLastSQLException, initializeConnection, openConnection, openDefaultConnection, openDefaultConnection, openDefaultConnection, openUserConnection, prepareCall, prepareCall, prepareCall, prepareStatement, prepareStatement, prepareStatement, prepareStatement, prepareStatement, prepareStatement, rollback, runBare, runBareOverridable, runScript, runScript, runSQLCommands, setAutoCommit, tearDown, usingDB2Client, usingDerbyNetClient, usingEmbedded

Methods inherited from class org.apache.derbyTesting.junit.BaseTestCase

alarm, assertDirectoryDeleted, assertEquals, assertEquals, assertEquals, assertEquals, assertEquals, assertExecJavaCmdAsExpected, assertLaunchedJUnitTestMethod, assertLaunchedJUnitTestMethod, assertSecurityManager, assertThrowableEquals, currentDirectory, execJavaCmd, execJavaCmd, fail, getClassVersionMajor, getEmmaJar, getFailureFolder, getFilesWith, getJavaExecutableName, getSystemProperty, getTestConfiguration, getTestResource, hasInterruptibleIO, isCVM, isIBMJVM, isJ9Platform, isJava5, isJava7, isJava8, isPhoneME, isPlatform, isSunJVM, isWindowsPlatform, openTestResource, println, printStackTrace, readProcessOutput, removeDirectory, removeDirectory, removeFiles, removeSystemProperty, runsWithEmma, runsWithJaCoCo, setSystemProperty, sleep, sleepAtLeastOneTick, traceit

Methods inherited from class junit.framework.TestCase

assertEquals, assertEquals, assertEquals, assertEquals, assertEquals, assertEquals, assertEquals, assertEquals, assertEquals, assertEquals, assertEquals, assertEquals, assertEquals, assertEquals, assertEquals, assertEquals, assertEquals, assertEquals, assertEquals, assertEquals, assertFalse, assertFalse, assertNotNull, assertNotNull, assertNotSame, assertNotSame, assertNull, assertNull, assertSame, assertSame, assertTrue, assertTrue, countTestCases, createResult, fail, fail, failNotEquals, failNotSame, failSame, format, getName, run, run, runTest, setName, setUp, toString

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

THREAD_COUNT

private static final int THREAD_COUNT

See Also:

Constant Field Values

syncObject

private java.lang.Object syncObject

startedCount

private int startedCount

listExceptions

private java.util.LinkedList listExceptions

Constructor Detail

DeadlockModeTest

public DeadlockModeTest(java.lang.String name)

Creates a new instance of DeadlockModeTest

Parameters:

name - identifier of the test

Method Detail

testThreadsUpdatingTable

public void testThreadsUpdatingTable()
                              throws java.lang.Exception

Tests for a deadlock on concurrent accesses to the database

Throws:

java.lang.Exception

createThreads

private void createThreads(java.lang.Thread[] t)
                    throws java.sql.SQLException

This method creates THREAD_COUNT threads which will all try to update the same table

Throws:

java.sql.SQLException

waitForThreads

private void waitForThreads(java.lang.Thread[] t)
                     throws java.lang.Exception

This method waits for the threads to finish their execution. This call will block the execution until signaled otherwise.

Throws:

java.lang.Exception

threadWorker

private void threadWorker(java.sql.Connection threadConnection)

This method has the code that each thread will be running. Since this will be running within different threads, we can not throw exceptions, therefore we make a "bogus" assertNull(string message,Exception e) call.

baseSuite

protected static junit.framework.Test baseSuite(java.lang.String name)

suite

public static junit.framework.Test suite()