Example usage for java.lang ClassNotFoundException getMessage

List of usage examples for java.lang ClassNotFoundException getMessage

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Introduction

In this page you can find the example usage for java.lang ClassNotFoundException getMessage.

Prototype

public String getMessage()

Source Link

Document

Returns the detail message string of this throwable.

Usage

From source file:org.apache.ignite.yardstick.cache.load.IgniteCacheRandomOperationBenchmark.java

/**
 * @throws Exception If failed.// w  w  w.  j a  v  a 2 s.c  om
 */
private void searchCache() throws Exception {
    availableCaches = new ArrayList<>(ignite().cacheNames().size());
    txCaches = new ArrayList<>();
    affCaches = new ArrayList<>();
    keysCacheClasses = new HashMap<>();
    valuesCacheClasses = new HashMap<>();
    replaceEntryProc = new BenchmarkReplaceValueEntryProcessor(null);
    rmvEntryProc = new BenchmarkRemoveEntryProcessor();
    cacheSqlDescriptors = new HashMap<>();
    operationStatistics = new HashMap<>();

    loadQueries();

    loadAllowedOperations();

    for (String cacheName : ignite().cacheNames()) {
        IgniteCache<Object, Object> cache = ignite().cache(cacheName);

        for (Operation op : Operation.values())
            operationStatistics.put(op + "_" + cacheName, new AtomicLong(0));

        CacheConfiguration configuration = cache.getConfiguration(CacheConfiguration.class);

        if (isClassDefinedInConfig(configuration)) {
            if (configuration.getMemoryMode() == CacheMemoryMode.OFFHEAP_TIERED
                    && configuration.getQueryEntities().size() > 2) {
                throw new IgniteException(
                        "Off-heap mode is unsupported by the load test due to bugs IGNITE-2982"
                                + " and IGNITE-2997");
            }

            ArrayList<Class> keys = new ArrayList<>();
            ArrayList<Class> values = new ArrayList<>();

            if (configuration.getQueryEntities() != null) {
                Collection<QueryEntity> entries = configuration.getQueryEntities();

                for (QueryEntity queryEntity : entries) {
                    try {
                        if (queryEntity.getKeyType() != null) {
                            Class keyCls = Class.forName(queryEntity.getKeyType());

                            if (ModelUtil.canCreateInstance(keyCls))
                                keys.add(keyCls);
                            else
                                throw new IgniteException("Class is unknown for the load test. Make sure you "
                                        + "specified its full name [clsName=" + queryEntity.getKeyType() + ']');
                        }

                        if (queryEntity.getValueType() != null) {
                            Class valCls = Class.forName(queryEntity.getValueType());

                            if (ModelUtil.canCreateInstance(valCls))
                                values.add(valCls);
                            else
                                throw new IgniteException("Class is unknown for the load test. Make sure you "
                                        + "specified its full name [clsName=" + queryEntity.getKeyType() + ']');

                            configureCacheSqlDescriptor(cacheName, queryEntity, valCls);
                        }
                    } catch (ClassNotFoundException e) {
                        BenchmarkUtils.println(e.getMessage());
                        BenchmarkUtils.println("This can be a BinaryObject. Ignoring exception.");

                        if (!cacheSqlDescriptors.containsKey(cacheName))
                            cacheSqlDescriptors.put(cacheName, new ArrayList<SqlCacheDescriptor>());
                    }
                }
            }

            if (configuration.getTypeMetadata() != null) {
                Collection<CacheTypeMetadata> entries = configuration.getTypeMetadata();

                for (CacheTypeMetadata cacheTypeMetadata : entries) {
                    try {
                        if (cacheTypeMetadata.getKeyType() != null) {
                            Class keyCls = Class.forName(cacheTypeMetadata.getKeyType());

                            if (ModelUtil.canCreateInstance(keyCls))
                                keys.add(keyCls);
                            else
                                throw new IgniteException("Class is unknown for the load test. Make sure you "
                                        + "specified its full name [clsName=" + cacheTypeMetadata.getKeyType()
                                        + ']');
                        }

                        if (cacheTypeMetadata.getValueType() != null) {
                            Class valCls = Class.forName(cacheTypeMetadata.getValueType());

                            if (ModelUtil.canCreateInstance(valCls))
                                values.add(valCls);
                            else
                                throw new IgniteException("Class is unknown for the load test. Make sure you "
                                        + "specified its full name [clsName=" + cacheTypeMetadata.getKeyType()
                                        + ']');
                        }
                    } catch (ClassNotFoundException e) {
                        BenchmarkUtils.println(e.getMessage());
                        BenchmarkUtils.println("This can be a BinaryObject. Ignoring exception.");

                        if (!cacheSqlDescriptors.containsKey(cacheName))
                            cacheSqlDescriptors.put(cacheName, new ArrayList<SqlCacheDescriptor>());
                    }
                }
            }

            keysCacheClasses.put(cacheName, keys.toArray(new Class[] {}));

            valuesCacheClasses.put(cacheName, values.toArray(new Class[] {}));
        } else
            keysCacheClasses.put(cacheName, new Class[] { randomKeyClass(cacheName) });

        valuesCacheClasses.put(cacheName, determineValueClasses(cacheName));

        if (configuration.getCacheMode() != CacheMode.LOCAL)
            affCaches.add(cache);

        if (configuration.getAtomicityMode() == CacheAtomicityMode.TRANSACTIONAL)
            txCaches.add(cache);

        availableCaches.add(cache);
    }
}

From source file:com.espertech.esperio.http.EsperIOHTTPAdapter.java

/**
 * Start the DDS endpoint.//from w w w. ja v a 2s .c  om
 */
public synchronized void start() {
    if (log.isInfoEnabled()) {
        log.info("Starting EsperIO HTTP Adapter for engine URI '" + engineURI + "'");
    }

    EPServiceProviderSPI engineSPI = (EPServiceProviderSPI) EPServiceProviderManager.getProvider(engineURI);

    // Start requests (output adapter)
    for (Request request : config.getRequests()) {

        EventType eventType = engineSPI.getEventAdapterService().getExistsTypeByName(request.getStream());
        if (eventType == null) {
            throw new ConfigurationException("Event type by name '" + request.getStream() + "' not found");
        }

        try {
            EsperIOHTTPSubscription subs = new EsperIOHTTPSubscription(request.getStream(), request.getUri());
            subs.seteventTypeName(request.getStream());
            subs.setSubscriptionName("EsperIOHTTP-" + request.getUri());
            subs.registerAdapter(engineSPI);
        } catch (Throwable t) {
            log.error(
                    "Error starting HTTP Request definition for URI " + request.getUri() + "'" + t.getMessage(),
                    t);
        }
    }

    // Configure services (input adapter)
    Set<Integer> ports = new HashSet<Integer>();
    for (Map.Entry<String, Service> entry : config.getServices().entrySet()) {
        if (services.containsKey(entry.getKey())) {
            throw new ConfigurationException(
                    "A service by name '" + entry.getKey() + "' has already been configured.");
        }

        int port = entry.getValue().getPort();
        if (ports.contains(port)) {
            throw new ConfigurationException("A service for port '" + port + "' has already been configured.");
        }
        ports.add(port);

        EsperHttpServiceBase httpService;
        if (entry.getValue().isNio()) {
            try {
                Class.forName("org.apache.http.nio.NHttpServiceHandler");
            } catch (ClassNotFoundException e) {
                throw new ConfigurationException(
                        "NIO Handler not found in classpath, please ensure httpcore-nio exists in classpath.");
            }
            httpService = new EsperHttpServiceNIO(entry.getKey(), entry.getValue());
        } else {
            httpService = new EsperHttpServiceClassic(entry.getKey(), entry.getValue());
        }
        services.put(entry.getKey(), httpService);
    }

    // Add handlers (input adapter)
    for (GetHandler handler : config.getGetHandlers()) {
        if (!services.containsKey(handler.getService())) {
            throw new ConfigurationException(
                    "A service by name '" + handler.getService() + "' has not been configured.");
        }
        EsperHttpServiceBase httpService = services.get(handler.getService());
        httpService.add(handler);
    }

    // Start services
    for (EsperHttpServiceBase service : services.values()) {
        try {
            service.start(engineSPI);
        } catch (IOException e) {
            log.error("Error starting service '" + service.getServiceName() + "' :" + e.getMessage());
        }
    }

    if (log.isInfoEnabled()) {
        log.info("Completed starting EsperIO HTTP Adapter for engine URI '" + engineURI + "'.");
    }
}

From source file:com.gemstone.gemfire.management.internal.cli.functions.DataCommandFunction.java

@SuppressWarnings({ "rawtypes" })
public DataCommandResult put(String key, String value, boolean putIfAbsent, String keyClass, String valueClass,
        String regionName) {/*  www .j  av a2s  .c om*/

    if (regionName == null || regionName.isEmpty()) {
        return DataCommandResult.createPutResult(key, null, null, CliStrings.PUT__MSG__REGIONNAME_EMPTY, false);
    }

    if (key == null || key.isEmpty()) {
        return DataCommandResult.createPutResult(key, null, null, CliStrings.PUT__MSG__KEY_EMPTY, false);
    }

    if (value == null || value.isEmpty()) {
        return DataCommandResult.createPutResult(key, null, null, CliStrings.PUT__MSG__VALUE_EMPTY, false);
    }

    Cache cache = CacheFactory.getAnyInstance();
    Region region = cache.getRegion(regionName);
    if (region == null) {
        return DataCommandResult.createPutResult(key, null, null,
                CliStrings.format(CliStrings.PUT__MSG__REGION_NOT_FOUND, regionName), false);
    } else {
        Object keyObject = null;
        Object valueObject = null;
        try {
            keyObject = getClassObject(key, keyClass);
        } catch (ClassNotFoundException e) {
            return DataCommandResult.createPutResult(key, null, null, "ClassNotFoundException " + keyClass,
                    false);
        } catch (IllegalArgumentException e) {
            return DataCommandResult.createPutResult(key, null, null,
                    "Error in converting JSON " + e.getMessage(), false);
        }

        try {
            valueObject = getClassObject(value, valueClass);
        } catch (ClassNotFoundException e) {
            return DataCommandResult.createPutResult(key, null, null, "ClassNotFoundException " + valueClass,
                    false);
        }
        Object returnValue;
        if (putIfAbsent && region.containsKey(keyObject))
            returnValue = region.get(keyObject);
        else
            returnValue = region.put(keyObject, valueObject);
        Object array[] = getJSONForNonPrimitiveObject(returnValue);
        DataCommandResult result = DataCommandResult.createPutResult(key, array[1], null, null, true);
        if (array[0] != null)
            result.setValueClass((String) array[0]);
        return result;
    }
}

From source file:org.apache.lens.ml.impl.LensMLImpl.java

/**
 * Inits the./*from   ww  w  . j a  v a 2  s. c  o m*/
 *
 * @param hiveConf the hive conf
 */
public synchronized void init(HiveConf hiveConf) {
    this.conf = hiveConf;

    // Get all the drivers
    String[] driverClasses = hiveConf.getStrings("lens.ml.drivers");

    if (driverClasses == null || driverClasses.length == 0) {
        throw new RuntimeException("No ML Drivers specified in conf");
    }

    log.info("Loading drivers " + Arrays.toString(driverClasses));
    drivers = new ArrayList<MLDriver>(driverClasses.length);

    for (String driverClass : driverClasses) {
        Class<?> cls;
        try {
            cls = Class.forName(driverClass);
        } catch (ClassNotFoundException e) {
            log.error("Driver class not found " + driverClass, e);
            continue;
        }

        if (!MLDriver.class.isAssignableFrom(cls)) {
            log.warn("Not a driver class " + driverClass);
            continue;
        }

        try {
            Class<? extends MLDriver> mlDriverClass = (Class<? extends MLDriver>) cls;
            MLDriver driver = mlDriverClass.newInstance();
            driver.init(toLensConf(conf));
            drivers.add(driver);
            log.info("Added driver " + driverClass);
        } catch (Exception e) {
            log.error("Failed to create driver " + driverClass + " reason: " + e.getMessage(), e);
        }
    }
    if (drivers.isEmpty()) {
        throw new RuntimeException("No ML drivers loaded");
    }

    log.info("Inited ML service");
}

From source file:com.gemstone.gemfire.management.internal.cli.functions.DataCommandFunction.java

@SuppressWarnings({ "rawtypes" })
public DataCommandResult get(String key, String keyClass, String valueClass, String regionName,
        Boolean loadOnCacheMiss) {

    Cache cache = CacheFactory.getAnyInstance();

    if (regionName == null || regionName.isEmpty()) {
        return DataCommandResult.createGetResult(key, null, null, CliStrings.GET__MSG__REGIONNAME_EMPTY, false);
    }//from  w ww .j  av  a 2  s  . c om

    if (key == null || key.isEmpty()) {
        return DataCommandResult.createGetResult(key, null, null, CliStrings.GET__MSG__KEY_EMPTY, false);
    }

    Region region = cache.getRegion(regionName);

    if (region == null) {
        if (logger.isDebugEnabled())
            logger.debug("Region Not Found - {}", regionName);
        return DataCommandResult.createGetResult(key, null, null,
                CliStrings.format(CliStrings.GET__MSG__REGION_NOT_FOUND, regionName), false);
    } else {
        Object keyObject = null;
        try {
            keyObject = getClassObject(key, keyClass);
        } catch (ClassNotFoundException e) {
            return DataCommandResult.createGetResult(key, null, null, "ClassNotFoundException " + keyClass,
                    false);
        } catch (IllegalArgumentException e) {
            return DataCommandResult.createGetResult(key, null, null,
                    "Error in converting JSON " + e.getMessage(), false);
        }

        // TODO determine whether the following conditional logic (assigned to 'doGet') is safer or necessary
        //boolean doGet = (Boolean.TRUE.equals(loadOnCacheMiss) && region.getAttributes().getCacheLoader() != null);
        boolean doGet = Boolean.TRUE.equals(loadOnCacheMiss);

        if (doGet || region.containsKey(keyObject)) {
            Object value = region.get(keyObject);
            if (logger.isDebugEnabled())
                logger.debug("Get for key {} value {}", key, value);
            //return DataCommandResult.createGetResult(key, value, null, null);
            Object array[] = getJSONForNonPrimitiveObject(value);
            if (value != null) {
                DataCommandResult result = DataCommandResult.createGetResult(key, array[1], null, null, true);
                if (array[0] != null)
                    result.setValueClass((String) array[0]);
                return result;
            } else {
                return DataCommandResult.createGetResult(key, array[1], null, null, false);
            }
        } else {
            if (logger.isDebugEnabled())
                logger.debug("Key is not present in the region {}", regionName);
            return DataCommandResult.createGetInfoResult(key, null, null,
                    CliStrings.GET__MSG__KEY_NOT_FOUND_REGION, false);
        }
    }
}

From source file:org.apache.wiki.PageManager.java

/**
 *  Creates a new PageManager./*from   www.ja  v  a 2  s.  c o m*/
 *  
 *  @param engine WikiEngine instance
 *  @param props Properties to use for initialization
 *  @throws WikiException If anything goes wrong, you get this.
 */
public PageManager(WikiEngine engine, Properties props) throws WikiException {
    super(engine);

    String classname;

    m_engine = engine;

    boolean useCache = "true".equals(props.getProperty(PROP_USECACHE));

    m_expiryTime = TextUtil.parseIntParameter(props.getProperty(PROP_LOCKEXPIRY), 60);

    //
    //  If user wants to use a cache, then we'll use the CachingProvider.
    //
    if (useCache) {
        classname = "org.apache.wiki.providers.CachingProvider";
    } else {
        classname = TextUtil.getRequiredProperty(props, PROP_PAGEPROVIDER);
    }

    try {
        log.debug("Page provider class: '" + classname + "'");

        Class providerclass = ClassUtil.findClass("org.apache.wiki.providers", classname);

        m_provider = (WikiPageProvider) providerclass.newInstance();

        log.debug("Initializing page provider class " + m_provider);
        m_provider.initialize(m_engine, props);
    } catch (ClassNotFoundException e) {
        log.error("Unable to locate provider class '" + classname + "'", e);
        throw new WikiException("No provider class.", e);
    } catch (InstantiationException e) {
        log.error("Unable to create provider class '" + classname + "'", e);
        throw new WikiException("Faulty provider class.", e);
    } catch (IllegalAccessException e) {
        log.error("Illegal access to provider class '" + classname + "'", e);
        throw new WikiException("Illegal provider class.", e);
    } catch (NoRequiredPropertyException e) {
        log.error("Provider did not found a property it was looking for: " + e.getMessage(), e);
        throw e; // Same exception works.
    } catch (IOException e) {
        log.error("An I/O exception occurred while trying to create a new page provider: " + classname, e);
        throw new WikiException("Unable to start page provider: " + e.getMessage(), e);
    }

}

From source file:org.apache.wiki.auth.authorize.GroupManager.java

/**
 * Returns the current external {@link GroupDatabase} in use. This method
 * is guaranteed to return a properly-initialized GroupDatabase, unless
 * it could not be initialized. In that case, this method throws
 * a {@link org.apache.wiki.api.exceptions.WikiException}. The GroupDatabase
 * is lazily initialized./*from   w w w  .jav  a 2s  .c  o  m*/
 * @throws org.apache.wiki.auth.WikiSecurityException if the GroupDatabase could
 * not be initialized
 * @return the current GroupDatabase
 * @since 2.3
 */
public final GroupDatabase getGroupDatabase() throws WikiSecurityException {
    if (m_groupDatabase != null) {
        return m_groupDatabase;
    }

    String dbClassName = "<unknown>";
    String dbInstantiationError = null;
    Throwable cause = null;
    try {
        Properties props = m_engine.getWikiProperties();
        dbClassName = props.getProperty(PROP_GROUPDATABASE);
        if (dbClassName == null) {
            dbClassName = XMLGroupDatabase.class.getName();
        }
        log.info("Attempting to load group database class " + dbClassName);
        Class<?> dbClass = ClassUtil.findClass("org.apache.wiki.auth.authorize", dbClassName);
        m_groupDatabase = (GroupDatabase) dbClass.newInstance();
        m_groupDatabase.initialize(m_engine, m_engine.getWikiProperties());
        log.info("Group database initialized.");
    } catch (ClassNotFoundException e) {
        log.error("GroupDatabase class " + dbClassName + " cannot be found.", e);
        dbInstantiationError = "Failed to locate GroupDatabase class " + dbClassName;
        cause = e;
    } catch (InstantiationException e) {
        log.error("GroupDatabase class " + dbClassName + " cannot be created.", e);
        dbInstantiationError = "Failed to create GroupDatabase class " + dbClassName;
        cause = e;
    } catch (IllegalAccessException e) {
        log.error("You are not allowed to access group database class " + dbClassName + ".", e);
        dbInstantiationError = "Access GroupDatabase class " + dbClassName + " denied";
        cause = e;
    } catch (NoRequiredPropertyException e) {
        log.error("Missing property: " + e.getMessage() + ".");
        dbInstantiationError = "Missing property: " + e.getMessage();
        cause = e;
    }

    if (dbInstantiationError != null) {
        throw new WikiSecurityException(
                dbInstantiationError + " Cause: " + (cause != null ? cause.getMessage() : ""), cause);
    }

    return m_groupDatabase;
}

From source file:org.apache.geode.management.internal.cli.functions.DataCommandFunction.java

@SuppressWarnings({ "rawtypes" })
public DataCommandResult get(Object principal, String key, String keyClass, String valueClass,
        String regionName, Boolean loadOnCacheMiss) {

    Cache cache = CacheFactory.getAnyInstance();

    if (regionName == null || regionName.isEmpty()) {
        return DataCommandResult.createGetResult(key, null, null, CliStrings.GET__MSG__REGIONNAME_EMPTY, false);
    }//w ww  .j  a  va2 s  .c o  m

    if (key == null || key.isEmpty()) {
        return DataCommandResult.createGetResult(key, null, null, CliStrings.GET__MSG__KEY_EMPTY, false);
    }

    Region region = cache.getRegion(regionName);

    if (region == null) {
        if (logger.isDebugEnabled())
            logger.debug("Region Not Found - {}", regionName);
        return DataCommandResult.createGetResult(key, null, null,
                CliStrings.format(CliStrings.GET__MSG__REGION_NOT_FOUND, regionName), false);
    } else {
        Object keyObject = null;
        try {
            keyObject = getClassObject(key, keyClass);
        } catch (ClassNotFoundException e) {
            return DataCommandResult.createGetResult(key, null, null, "ClassNotFoundException " + keyClass,
                    false);
        } catch (IllegalArgumentException e) {
            return DataCommandResult.createGetResult(key, null, null,
                    "Error in converting JSON " + e.getMessage(), false);
        }

        // TODO determine whether the following conditional logic (assigned to 'doGet') is safer or
        // necessary
        // boolean doGet = (Boolean.TRUE.equals(loadOnCacheMiss) &&
        // region.getAttributes().getCacheLoader() != null);
        boolean doGet = Boolean.TRUE.equals(loadOnCacheMiss);

        if (doGet || region.containsKey(keyObject)) {
            Object value = region.get(keyObject);

            // run it through post processor. region.get will return the deserialized object already, so
            // we don't need to
            // deserialize it anymore to pass it to the postProcessor
            value = this.securityService.postProcess(principal, regionName, keyObject, value, false);

            if (logger.isDebugEnabled())
                logger.debug("Get for key {} value {}", key, value);
            // return DataCommandResult.createGetResult(key, value, null, null);
            Object array[] = getJSONForNonPrimitiveObject(value);
            if (value != null) {
                DataCommandResult result = DataCommandResult.createGetResult(key, array[1], null, null, true);
                if (array[0] != null)
                    result.setValueClass((String) array[0]);
                return result;
            } else {
                return DataCommandResult.createGetResult(key, array[1], null, null, false);
            }
        } else {
            if (logger.isDebugEnabled())
                logger.debug("Key is not present in the region {}", regionName);
            return DataCommandResult.createGetInfoResult(key, null, null,
                    CliStrings.GET__MSG__KEY_NOT_FOUND_REGION, false);
        }
    }
}

From source file:com.ecyrd.jspwiki.PageManager.java

/**
 *  Creates a new PageManager.//from   w  ww .  j  a v a  2  s  . c om
 *  
 *  @param engine WikiEngine instance
 *  @param props Properties to use for initialization
 *  @throws WikiException If anything goes wrong, you get this.
 */
public PageManager(WikiEngine engine, Properties props) throws WikiException {
    super(engine);

    String classname;

    m_engine = engine;

    boolean useCache = "true".equals(props.getProperty(PROP_USECACHE));

    m_expiryTime = TextUtil.parseIntParameter(props.getProperty(PROP_LOCKEXPIRY), 60);

    //
    //  If user wants to use a cache, then we'll use the CachingProvider.
    //
    if (useCache) {
        classname = "com.ecyrd.jspwiki.providers.CachingProvider";
    } else {
        classname = WikiEngine.getRequiredProperty(props, PROP_PAGEPROVIDER);
    }

    try {
        log.debug("Page provider class: '" + classname + "'");

        Class providerclass = ClassUtil.findClass("com.ecyrd.jspwiki.providers", classname);

        m_provider = (WikiPageProvider) providerclass.newInstance();

        log.debug("Initializing page provider class " + m_provider);
        m_provider.initialize(m_engine, props);
    } catch (ClassNotFoundException e) {
        log.error("Unable to locate provider class '" + classname + "'", e);
        throw new WikiException("No provider class.", e);
    } catch (InstantiationException e) {
        log.error("Unable to create provider class '" + classname + "'", e);
        throw new WikiException("Faulty provider class.", e);
    } catch (IllegalAccessException e) {
        log.error("Illegal access to provider class '" + classname + "'", e);
        throw new WikiException("Illegal provider class.", e);
    } catch (NoRequiredPropertyException e) {
        log.error("Provider did not found a property it was looking for: " + e.getMessage(), e);
        throw e; // Same exception works.
    } catch (IOException e) {
        log.error("An I/O exception occurred while trying to create a new page provider: " + classname, e);
        throw new WikiException("Unable to start page provider: " + e.getMessage(), e);
    }

}

From source file:com.ecyrd.jspwiki.auth.authorize.GroupManager.java

/**
 * Returns the current external {@link GroupDatabase} in use. This method
 * is guaranteed to return a properly-initialized GroupDatabase, unless
 * it could not be initialized. In that case, this method throws
 * a {@link com.ecyrd.jspwiki.WikiException}. The GroupDatabase
 * is lazily initialized.//  w  w  w.  j ava2 s.  com
 * @throws com.ecyrd.jspwiki.auth.WikiSecurityException if the GroupDatabase could
 * not be initialized
 * @return the current GroupDatabase
 * @since 2.3
 */
public final GroupDatabase getGroupDatabase() throws WikiSecurityException {
    if (m_groupDatabase != null) {
        return m_groupDatabase;
    }

    String dbClassName = "<unknown>";
    String dbInstantiationError = null;
    Throwable cause = null;
    try {
        Properties props = m_engine.getWikiProperties();
        dbClassName = props.getProperty(PROP_GROUPDATABASE);
        if (dbClassName == null) {
            dbClassName = XMLGroupDatabase.class.getName();
        }
        log.info("Attempting to load group database class " + dbClassName);
        Class<?> dbClass = ClassUtil.findClass("com.ecyrd.jspwiki.auth.authorize", dbClassName);
        m_groupDatabase = (GroupDatabase) dbClass.newInstance();
        m_groupDatabase.initialize(m_engine, m_engine.getWikiProperties());
        log.info("Group database initialized.");
    } catch (ClassNotFoundException e) {
        log.error("GroupDatabase class " + dbClassName + " cannot be found.", e);
        dbInstantiationError = "Failed to locate GroupDatabase class " + dbClassName;
        cause = e;
    } catch (InstantiationException e) {
        log.error("GroupDatabase class " + dbClassName + " cannot be created.", e);
        dbInstantiationError = "Failed to create GroupDatabase class " + dbClassName;
        cause = e;
    } catch (IllegalAccessException e) {
        log.error("You are not allowed to access group database class " + dbClassName + ".", e);
        dbInstantiationError = "Access GroupDatabase class " + dbClassName + " denied";
        cause = e;
    } catch (NoRequiredPropertyException e) {
        log.error("Missing property: " + e.getMessage() + ".");
        dbInstantiationError = "Missing property: " + e.getMessage();
        cause = e;
    }

    if (dbInstantiationError != null) {
        throw new WikiSecurityException(
                dbInstantiationError + " Cause: " + (cause != null ? cause.getMessage() : ""), cause);
    }

    return m_groupDatabase;
}