DataModelerEventObserver.java

/*
 * Copyright 2015 Red Hat, Inc. and/or its affiliates.
 *
 * 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.kie.workbench.common.screens.datamodeller.backend.server;

import javax.enterprise.context.ApplicationScoped;
import javax.enterprise.event.Observes;
import javax.inject.Inject;
import javax.inject.Named;
import javax.persistence.Entity;

import org.kie.workbench.common.screens.datamodeller.events.DataObjectCreatedEvent;
import org.kie.workbench.common.screens.datamodeller.events.DataObjectDeletedEvent;
import org.kie.workbench.common.screens.datamodeller.model.persistence.PersistenceDescriptorModel;
import org.kie.workbench.common.screens.datamodeller.model.persistence.PersistenceUnitModel;
import org.kie.workbench.common.screens.datamodeller.service.PersistenceDescriptorService;
import org.kie.workbench.common.services.datamodeller.core.DataObject;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.uberfire.backend.server.util.Paths;
import org.uberfire.backend.vfs.Path;
import org.uberfire.io.IOService;

@ApplicationScoped
public class DataModelerEventObserver {

    private static final Logger logger = LoggerFactory.getLogger( DataModelerEventObserver.class );

    private PersistenceDescriptorService descriptorService;

    private IOService ioService;

    public DataModelerEventObserver() {
    }

    @Inject
    public DataModelerEventObserver( final PersistenceDescriptorService descriptorService,
            final @Named( "ioStrategy" ) IOService ioService ) {
        this.descriptorService = descriptorService;
        this.ioService = ioService;
    }

    public void onDataObjectCreated( @Observes DataObjectCreatedEvent event ) {
        Path descriptorPath;
        PersistenceDescriptorModel persistenceDescriptor;

        if ( isPersistable( event.getCurrentDataObject() ) ) {
            descriptorPath = descriptorService.calculatePersistenceDescriptorPath( event.getCurrentProject() );
            persistenceDescriptor = safeLoad( descriptorPath );
            if ( persistenceDescriptor != null &&
                    !containsClass( persistenceDescriptor.getPersistenceUnit(), event.getCurrentDataObject().getClassName() ) ) {
                persistenceDescriptor.getPersistenceUnit().getClasses().add( event.getCurrentDataObject().getClassName() );
                descriptorService.save( descriptorPath,
                        persistenceDescriptor,
                        null,
                        "Entity added to persistence descriptor" );
            }
        }
    }

    public void onDataObjectDeleted( @Observes DataObjectDeletedEvent event ) {
        Path descriptorPath;
        PersistenceDescriptorModel persistenceDescriptor;

        descriptorPath = descriptorService.calculatePersistenceDescriptorPath( event.getCurrentProject() );
        persistenceDescriptor = safeLoad( descriptorPath );

        if ( persistenceDescriptor != null &&
                containsClass( persistenceDescriptor.getPersistenceUnit(), event.getCurrentDataObject().getClassName() ) ) {
            persistenceDescriptor.getPersistenceUnit().getClasses().remove( event.getCurrentDataObject().getClassName() );
            descriptorService.save( descriptorPath,
                    persistenceDescriptor,
                    null,
                    "Entity removed from persistence descriptor" );
        }
    }

    private boolean containsClass( PersistenceUnitModel persistenceUnit, String className ) {
        return persistenceUnit != null &&
                persistenceUnit.getClasses() != null &&
                persistenceUnit.getClasses().contains( className );
    }

    private PersistenceDescriptorModel safeLoad( final Path path ) {
        try {
            if ( path != null && ioService.exists( Paths.convert( path ) ) ) {
                return descriptorService.load( path );
            }
        } catch ( Exception e ) {
            logger.warn( "It was not possible to read persistence descriptor por project: " + path );
        }
        return null;
    }

    private boolean isPersistable( DataObject dataObject ) {
        return dataObject != null && dataObject.getAnnotation( Entity.class.getName() ) != null;
    }

}