DbreMetadataProviderImpl.java

package org.springframework.roo.addon.dbre.addon;

import static org.springframework.roo.model.RooJavaType.ROO_DB_MANAGED;

import java.util.List;
import java.util.logging.Logger;

import org.apache.felix.scr.annotations.Component;
import org.apache.felix.scr.annotations.Service;
import org.osgi.framework.InvalidSyntaxException;
import org.osgi.framework.ServiceReference;
import org.osgi.service.component.ComponentContext;
import org.springframework.roo.addon.dbre.addon.model.Database;
import org.springframework.roo.addon.dbre.addon.model.DbreModelService;
import org.springframework.roo.classpath.PhysicalTypeIdentifier;
import org.springframework.roo.classpath.PhysicalTypeMetadata;
import org.springframework.roo.classpath.TypeManagementService;
import org.springframework.roo.classpath.customdata.CustomDataKeys;
import org.springframework.roo.classpath.details.ClassOrInterfaceTypeDetails;
import org.springframework.roo.classpath.details.FieldMetadata;
import org.springframework.roo.classpath.itd.AbstractItdMetadataProvider;
import org.springframework.roo.classpath.itd.ItdTypeDetailsProvidingMetadataItem;
import org.springframework.roo.metadata.MetadataDependencyRegistry;
import org.springframework.roo.metadata.internal.MetadataDependencyRegistryTracker;
import org.springframework.roo.model.JavaType;
import org.springframework.roo.model.RooJavaType;
import org.springframework.roo.project.LogicalPath;
import org.springframework.roo.support.logging.HandlerUtils;

/**
 * Implementation of {@link DbreMetadataProvider}.
 * 
 * @author Alan Stewart
 * @author Enrique Ruiz at DISID Corporation S.L.
 * @since 1.1
 */
@Component
@Service
public class DbreMetadataProviderImpl extends AbstractItdMetadataProvider implements
    DbreMetadataProvider {

  protected final static Logger LOGGER = HandlerUtils.getLogger(DbreMetadataProviderImpl.class);

  private DbreModelService dbreModelService;
  private TypeManagementService typeManagementService;
  protected MetadataDependencyRegistryTracker registryTracker = null;

  /**
   * This service is being activated so setup it:
   * <ul>
   * <li>Create and open the {@link MetadataDependencyRegistryTracker}</li>
   * <li>Registers {@link RooJavaType#ROO_DB_MANAGED} as additional JavaType 
   * that will trigger metadata registration.</li>
   * </ul>
   */
  @Override
  protected void activate(final ComponentContext cContext) {
    context = cContext.getBundleContext();
    this.registryTracker =
        new MetadataDependencyRegistryTracker(context, null,
            PhysicalTypeIdentifier.getMetadataIdentiferType(), getProvidesType());
    this.registryTracker.open();
    addMetadataTrigger(ROO_DB_MANAGED);
  }

  /**
   * This service is being deactivated so unregister upstream-downstream 
   * dependencies, triggers, matchers and listeners.
   * 
   * @param context
   */
  protected void deactivate(final ComponentContext context) {
    MetadataDependencyRegistry registry = this.registryTracker.getService();
    registry.deregisterDependency(PhysicalTypeIdentifier.getMetadataIdentiferType(),
        getProvidesType());
    this.registryTracker.close();
    removeMetadataTrigger(ROO_DB_MANAGED);
  }

  @Override
  protected String createLocalIdentifier(final JavaType javaType, final LogicalPath path) {
    return DbreMetadata.createIdentifier(javaType, path);
  }

  @Override
  protected String getGovernorPhysicalTypeIdentifier(final String metadataIdentificationString) {
    final JavaType javaType = DbreMetadata.getJavaType(metadataIdentificationString);
    final LogicalPath path = DbreMetadata.getPath(metadataIdentificationString);
    return PhysicalTypeIdentifier.createIdentifier(javaType, path);
  }

  private IdentifierHolder getIdentifierHolder(final JavaType javaType) {
    final List<FieldMetadata> identifierFields =
        getPersistenceMemberLocator().getIdentifierFields(javaType);
    if (identifierFields.isEmpty()) {
      return null;
    }

    final FieldMetadata identifierField = identifierFields.get(0);
    final boolean embeddedIdField =
        identifierField.getCustomData().get(CustomDataKeys.EMBEDDED_ID_FIELD) != null;
    final List<FieldMetadata> embeddedIdFields =
        getPersistenceMemberLocator().getEmbeddedIdentifierFields(javaType);
    return new IdentifierHolder(identifierField, embeddedIdField, embeddedIdFields);
  }

  public String getItdUniquenessFilenameSuffix() {
    return "DbManaged";
  }

  @Override
  protected ItdTypeDetailsProvidingMetadataItem getMetadata(
      final String metadataIdentificationString, final JavaType aspectName,
      final PhysicalTypeMetadata governorPhysicalTypeMetadata, final String itdFilename) {
    // We need to parse the annotation, which we expect to be present
    final DbManagedAnnotationValues annotationValues =
        new DbManagedAnnotationValues(governorPhysicalTypeMetadata);
    if (!annotationValues.isAnnotationFound()) {
      return null;
    }

    // Abort if the database couldn't be deserialized. This can occur if the
    // DBRE XML file has been deleted or is empty.
    final Database database = getDbreModelService().getDatabase(false);
    if (database == null) {
      return null;
    }

    // We know governor type details are non-null and can be safely cast
    final JavaType javaType = governorPhysicalTypeMetadata.getMemberHoldingTypeDetails().getName();
    final IdentifierHolder identifierHolder = getIdentifierHolder(javaType);
    if (identifierHolder == null) {
      return null;
    }

    final FieldMetadata versionField = getVersionField(javaType, metadataIdentificationString);

    // Search for database-managed entities
    final Iterable<ClassOrInterfaceTypeDetails> managedEntities =
        getTypeLocationService().findClassesOrInterfaceDetailsWithAnnotation(ROO_DB_MANAGED);

    boolean found = false;
    for (final ClassOrInterfaceTypeDetails managedEntity : managedEntities) {
      if (managedEntity.getName().equals(javaType)) {
        found = true;
        break;
      }
    }
    if (!found) {
      final String mid = getTypeLocationService().getPhysicalTypeIdentifier(javaType);
      getMetadataDependencyRegistry().registerDependency(mid, metadataIdentificationString);
      return null;
    }

    final DbreMetadata dbreMetadata =
        new DbreMetadata(metadataIdentificationString, aspectName, governorPhysicalTypeMetadata,
            annotationValues, identifierHolder, versionField, managedEntities, database);
    final ClassOrInterfaceTypeDetails updatedGovernor = dbreMetadata.getUpdatedGovernor();
    if (updatedGovernor != null) {
      getTypeManagementService().createOrUpdateTypeOnDisk(updatedGovernor);
    }
    return dbreMetadata;
  }

  public String getProvidesType() {
    return DbreMetadata.getMetadataIdentiferType();
  }

  private FieldMetadata getVersionField(final JavaType domainType,
      final String metadataIdentificationString) {
    return getPersistenceMemberLocator().getVersionField(domainType);
  }

  public DbreModelService getDbreModelService() {
    if (dbreModelService == null) {
      // Get all Services implement DbreModelService interface
      try {
        ServiceReference<?>[] references =
            context.getAllServiceReferences(DbreModelService.class.getName(), null);

        for (ServiceReference<?> ref : references) {
          return (DbreModelService) context.getService(ref);
        }

        return null;

      } catch (InvalidSyntaxException e) {
        LOGGER.warning("Cannot load DbreModelService on DbreMetadataProviderImpl.");
        return null;
      }
    } else {
      return dbreModelService;
    }
  }

  public TypeManagementService getTypeManagementService() {
    if (typeManagementService == null) {
      // Get all Services implement TypeManagementService interface
      try {
        ServiceReference<?>[] references =
            context.getAllServiceReferences(TypeManagementService.class.getName(), null);

        for (ServiceReference<?> ref : references) {
          return (TypeManagementService) context.getService(ref);
        }

        return null;

      } catch (InvalidSyntaxException e) {
        LOGGER.warning("Cannot load TypeManagementService on DbreMetadataProviderImpl.");
        return null;
      }
    } else {
      return typeManagementService;
    }
  }
}