# AbstractSQLIndexQueryAssembler.java

    /*
     * Copyright (c) 2010, Stanislav Muhametsin. All Rights Reserved.
     * Copyright (c) 2012, Paul Merlin. All Rights Reserved.
     *
     * 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.qi4j.index.sql.assembly;

    import java.io.IOException;
    import org.qi4j.api.common.Visibility;
    import org.qi4j.bootstrap.Assemblers;
    import org.qi4j.bootstrap.AssemblyException;
    import org.qi4j.bootstrap.ModuleAssembly;
    import org.qi4j.index.reindexer.ReindexerConfiguration;
    import org.qi4j.index.reindexer.ReindexerService;
    import org.qi4j.index.sql.support.common.ReindexingStrategy;
    import org.qi4j.library.sql.common.SQLConfiguration;
    import org.sql.generation.api.vendor.SQLVendor;
    import org.sql.generation.api.vendor.SQLVendorProvider;

    public abstract class AbstractSQLIndexQueryAssembler<AssemblerType>
        extends Assemblers.VisibilityIdentityConfig<AssemblerType>
    {
        public static final String DEFAULT_IDENTITY = "indexing-sql";

        private Class<? extends ReindexingStrategy> reindexingStrategy = ReindexingStrategy.NeverNeed.class;

        public AbstractSQLIndexQueryAssembler()
        {
            identifiedBy( DEFAULT_IDENTITY );
        }

        @SuppressWarnings( "unchecked" )
        public AssemblerType withReindexingStrategy( Class<? extends ReindexingStrategy> reindexingStrategy )
        {
            this.reindexingStrategy = reindexingStrategy;
            return (AssemblerType) this;
        }

        protected SQLVendor getSQLVendor()
            throws IOException
        {
            return SQLVendorProvider.createVendor( SQLVendor.class );
        }

        protected abstract Class<?> getIndexQueryServiceType();

        @Override
        public final void assemble( ModuleAssembly module )
            throws AssemblyException
        {
            try
            {
                SQLVendor sqlVendor = getSQLVendor();
                if( sqlVendor == null )
                {
                    throw new AssemblyException( "SQL Vendor could not be determined." );
                }
                module.services( getIndexQueryServiceType() )
                    .identifiedBy( identity() )
                    .setMetaInfo( sqlVendor )
                    .visibleIn( visibility() )
                    .instantiateOnStartup();
            }
            catch( IOException ex )
            {
                throw new AssemblyException( "SQL Vendor could not be created", ex );
            }

            module.services( ReindexerService.class ).
                visibleIn( Visibility.module );
            module.services( ReindexingStrategy.class ).
                withMixins( reindexingStrategy ).
                visibleIn( Visibility.module );

            if( hasConfig() )
            {
                configModule().entities( SQLConfiguration.class,
                                         ReindexerConfiguration.class ).
                    visibleIn( configVisibility() );
            }
        }

    }