nametdcacheable.java

derby database source code.good for you.

/*

   Derby - Class org.apache.derby.impl.sql.catalog.NameTDCacheable

   Copyright 1997, 2004 The Apache Software Foundation or its licensors, as applicable.

   Licensed under the Apache License, Version 2.0 (the "License");
   you may not use this file except in compliance with the License.
   You may obtain a copy of the License at

      http://www.apache.org/licenses/LICENSE-2.0

   Unless required by applicable law or agreed to in writing, software
   distributed under the License is distributed on an "AS IS" BASIS,
   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   See the License for the specific language governing permissions and
   limitations under the License.

 */

package org.apache.derby.impl.sql.catalog;

import org.apache.derby.iapi.services.cache.Cacheable;

import org.apache.derby.iapi.sql.dictionary.SchemaDescriptor;
import org.apache.derby.iapi.sql.dictionary.TableDescriptor;

import org.apache.derby.iapi.error.StandardException;

import org.apache.derby.iapi.services.sanity.SanityManager;

/**
 * This class implements a Cacheable for a DataDictionary cache of
 * table descriptors, with the lookup key being the name of the table.
 *
 * Assumes client passes in a string that includes the schema name.
 */
class NameTDCacheable extends TDCacheable
{
	private TableKey identity;

	NameTDCacheable(DataDictionaryImpl dd) {
		super(dd);
	}


	/* Cacheable interface */

	/** @see Cacheable#clearIdentity */
	public void clearIdentity()
	{
		identity = null;
		td = null;
	}

	/** @see Cacheable#getIdentity */
	public Object getIdentity()
	{
		return identity;
	}

	/** @see Cacheable#createIdentity */
	public Cacheable createIdentity(Object key, Object createParameter)
	{
		if (SanityManager.DEBUG)
		{
			if (!(key instanceof TableKey))
			{
				SanityManager.THROWASSERT("Key for a NameTDCacheElement is a " +
					key.getClass().getName() +
					" instead of a TableKey");
			}

			if (!(createParameter instanceof TableDescriptor))
			{
				SanityManager.THROWASSERT("Create parameter for a NameTDCacheElement is a " +
					createParameter.getClass().getName() +
					"instead of a TableDescriptorImpl");
			}			
		}

		identity = (TableKey)key;
		td = (TableDescriptor) createParameter;

		if (td != null)
			return this;
		else
			return null;
	}

	/**
	 * @see Cacheable#setIdentity
	 *
	 * @exception StandardException		Thrown on error
	 */
	public Cacheable setIdentity(Object key) throws StandardException
	{
		if (SanityManager.DEBUG)
		{
			if (!(key instanceof TableKey))
			{
				SanityManager.THROWASSERT("Key for a NameTDCacheElement is a " +
					key.getClass().getName() +
					" instead of a TableKey");
			}
		}

		;
		td = dd.getUncachedTableDescriptor(identity = (TableKey)key);

		if (td != null)
		{
			// add table descriptor to the oidTdcache in the Datadictionary.
			// no fear of deadlocks because this is called outside the 
			// synchronize block in the cache code.
			dd.addTableDescriptorToOtherCache(td, this);
			return this;
		}
		else
			return null;
	}

	/**
	  @exception StandardException		Thrown on error
	  */
	// If this code is required it should be moved into a D_ class. - djd

/*
	public boolean isConsistent(HeaderPrintWriter reportInconsistent)
		throws StandardException
	{
		boolean retval = true;

		if (SanityManager.DEBUG)
		{
			TableDescriptor uncachedTD;

			try
			{
				uncachedTD = dd.getUncachedTableDescriptor(identity);
			}
			catch (StandardException se)
			{
				reportInconsistent.println("Unexpected exception " + se +
				  " while getting cached table descriptor in NameTDCacheable.");
				uncachedTD = null;
			}

			retval = checkConsistency(uncachedTD, identity, reportInconsistent);
		}

		return retval;
	}
	*/
}