plugins/org.eclipse.wst.common.frameworks/src/org/eclipse/wst/common/frameworks/datamodel/DataModelFactory.java

/*******************************************************************************
 * Copyright (c) 2003, 2005 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 * 
 * Contributors:
 * IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.wst.common.frameworks.datamodel;

import java.util.List;

import org.eclipse.wst.common.frameworks.internal.datamodel.DataModelExtensionReader;
import org.eclipse.wst.common.frameworks.internal.datamodel.DataModelImpl;

public class DataModelFactory {

	private static DataModelExtensionReader reader;

	/**
	 * Looks up the appropriate IDataModelProvider by the specified id and
	 * constructs a new IDataModel. If the IDataModelProvider is not found then
	 * a RuntimeException is logged and null is returned.
	 * 
	 * @param dataModelProviderID
	 *            the id of the IDataModelProvider
	 * @return a new IDataModel
	 */
	public static IDataModel createDataModel(String dataModelProviderID) {
        IDataModelProvider provider = loadProvider(dataModelProviderID);
        if(provider == null) 
            return null;
		return createDataModel(provider);
	}

	protected static IDataModelProvider loadProvider(String id) {
		if (null == reader) {
			reader = new DataModelExtensionReader();
		}
		return reader.getProvider(id);
	}
    /**
     * Looks up the appropriate IDataModelProvider by the specified provider Type String and functionGroupID String and
     * constructs an array of new DataModelProviderDescriptor. If the IDataModelProvider is not found then
     * a RuntimeException is logged and null is returned.
     * 
     * @param providerKind
     *            the String id of the provider
     *            
     * @return DataModelProviderDescriptor[]
     */
    public static DataModelProviderDescriptor[] getProviderDescriptorsForProviderKind(String providerKind) {
        List providers = loadProviderForProviderKind(providerKind);
        if(providers == null || providers.isEmpty()) 
            return null;
        return (DataModelProviderDescriptor[])providers.toArray(new DataModelProviderDescriptor[providers.size()]);
    }

    private static List loadProviderForProviderKind(String providerKind) {
        if (null == reader) {
            reader = new DataModelExtensionReader();
        }
        return reader.getProviderDescriptorsForProviderKind(providerKind);
    }
	/**
	 * Looks up the appropriate IDataModelProvider using the name of the
	 * specified class. This method is equavalent to
	 * <code>createDataModel(dataModelProviderClassID.getName())</code>.
	 * 
	 * @param dataModelProviderClass
	 *            the class whose name is the id of the IDataModelProvider
	 * @return a new IDataModel
	 */
	public static IDataModel createDataModel(Class dataModelProviderID) {
		return createDataModel(dataModelProviderID.getName());
	}

	/**
	 * Creates a new IDataModel using the the specified instance of an
	 * IDataModelProvider
	 * 
	 * @param dataModelProviderInstance
	 * @return a new IDataModel
	 */
	public static IDataModel createDataModel(IDataModelProvider provider) {
		if (null == provider) {
			throw new NullPointerException();
		}
		DataModelImpl dataModel = new DataModelImpl(provider);
		return dataModel;
	}

}