SerializableMetadata.java

package org.springframework.roo.addon.javabean.addon;

import static java.lang.reflect.Modifier.FINAL;
import static java.lang.reflect.Modifier.PRIVATE;
import static java.lang.reflect.Modifier.STATIC;
import static org.springframework.roo.model.JavaType.LONG_PRIMITIVE;
import static org.springframework.roo.model.JdkJavaType.SERIALIZABLE;

import org.apache.commons.lang3.Validate;
import org.apache.commons.lang3.builder.ToStringBuilder;
import org.springframework.roo.addon.javabean.annotations.RooSerializable;
import org.springframework.roo.classpath.PhysicalTypeIdentifierNamingUtils;
import org.springframework.roo.classpath.PhysicalTypeMetadata;
import org.springframework.roo.classpath.customdata.CustomDataKeys;
import org.springframework.roo.classpath.details.FieldMetadataBuilder;
import org.springframework.roo.classpath.details.ItdTypeDetails;
import org.springframework.roo.classpath.details.ItdTypeDetailsBuilder;
import org.springframework.roo.classpath.itd.AbstractItdTypeDetailsProvidingMetadataItem;
import org.springframework.roo.metadata.MetadataIdentificationUtils;
import org.springframework.roo.model.JavaSymbolName;
import org.springframework.roo.model.JavaType;
import org.springframework.roo.project.LogicalPath;

/**
 * Metadata for {@link RooSerializable}.
 * 
 * @author Alan Stewart
 * @since 1.1
 */
public class SerializableMetadata extends AbstractItdTypeDetailsProvidingMetadataItem {

  private static final String DEFAULT_SERIAL_VERSION = "1L";
  private static final String PROVIDES_TYPE_STRING = SerializableMetadata.class.getName();
  private static final String PROVIDES_TYPE = MetadataIdentificationUtils
      .create(PROVIDES_TYPE_STRING);
  static final JavaSymbolName SERIAL_VERSION_FIELD = new JavaSymbolName("serialVersionUID");

  public static String createIdentifier(final JavaType javaType, final LogicalPath path) {
    return PhysicalTypeIdentifierNamingUtils.createIdentifier(PROVIDES_TYPE_STRING, javaType, path);
  }

  public static JavaType getJavaType(final String metadataIdentificationString) {
    return PhysicalTypeIdentifierNamingUtils.getJavaType(PROVIDES_TYPE_STRING,
        metadataIdentificationString);
  }

  public static String getMetadataIdentiferType() {
    return PROVIDES_TYPE;
  }

  public static LogicalPath getPath(final String metadataIdentificationString) {
    return PhysicalTypeIdentifierNamingUtils.getPath(PROVIDES_TYPE_STRING,
        metadataIdentificationString);
  }

  public static boolean isValid(final String metadataIdentificationString) {
    return PhysicalTypeIdentifierNamingUtils.isValid(PROVIDES_TYPE_STRING,
        metadataIdentificationString);
  }

  /**
   * Constructor
   * 
   * @param identifier
   * @param aspectName
   * @param governorPhysicalTypeMetadata
   */
  public SerializableMetadata(final String identifier, final JavaType aspectName,
      final PhysicalTypeMetadata governorPhysicalTypeMetadata) {
    super(identifier, aspectName, governorPhysicalTypeMetadata);
    Validate.isTrue(isValid(identifier), "Metadata id '%s' is invalid", identifier);

    if (isValid()) {
      ensureGovernorImplements(SERIALIZABLE);
      addSerialVersionUIDFieldIfRequired();
      buildItd();
    }
  }

  /**
   * Adds a "serialVersionUID" field to the {@link ItdTypeDetailsBuilder} if
   * the governor doesn't already contain it.
   */
  private void addSerialVersionUIDFieldIfRequired() {
    if (!governorTypeDetails.declaresField(SERIAL_VERSION_FIELD)) {
      builder.addField(createSerialVersionField());
    }
  }

  /**
   * Generates a field to store the serialization ID
   * 
   * @return a non-<code>null</code> field
   */
  private FieldMetadataBuilder createSerialVersionField() {
    final FieldMetadataBuilder fieldBuilder =
        new FieldMetadataBuilder(getId(), PRIVATE | STATIC | FINAL, SERIAL_VERSION_FIELD,
            LONG_PRIMITIVE, DEFAULT_SERIAL_VERSION);
    fieldBuilder.getCustomData().put(CustomDataKeys.SERIAL_VERSION_UUID_FIELD, true);
    return fieldBuilder;
  }

  /**
   * For unit testing
   * 
   * @return
   */
  ItdTypeDetails getItdTypeDetails() {
    return itdTypeDetails;
  }

  @Override
  public String toString() {
    final ToStringBuilder builder = new ToStringBuilder(this);
    builder.append("identifier", getId());
    builder.append("valid", valid);
    builder.append("aspectName", aspectName);
    builder.append("destinationType", destination);
    builder.append("governor", governorPhysicalTypeMetadata.getId());
    builder.append("itdTypeDetails", itdTypeDetails);
    return builder.toString();
  }
}