MemberHoldingTypeDetailsMetadataItem.java

package org.springframework.roo.classpath.itd;

import org.springframework.roo.classpath.details.MemberHoldingTypeDetails;
import org.springframework.roo.classpath.scanner.MemberDetailsScanner;
import org.springframework.roo.metadata.MetadataItem;

/**
 * Indicates a {@link MetadataItem} capable of returning
 * {@link MemberHoldingTypeDetails}.
 * <p>
 * Most Roo metadata builds types, and therefore can provide member information
 * via the {@link MemberHoldingTypeDetails} interface. This interface offers a
 * convenient way for discovering available member information for iteration
 * etc. See for example {@link MemberDetailsScanner} for a common usage pattern.
 * 
 * @author Ben Alex
 * @since 1.1.1
 * @param <T> the type of {@link MemberHoldingTypeDetails} that will be provided
 */
public interface MemberHoldingTypeDetailsMetadataItem<T extends MemberHoldingTypeDetails> extends
    MetadataItem {

  /**
   * Obtains the {@link MemberHoldingTypeDetails}, if available.
   * <p>
   * An {@link MemberHoldingTypeDetails} should be returned even if no members
   * should be introduced. Only return null if there was a failure during
   * parsing or other unexpected condition.
   * 
   * @return the details, or null if the details are unavailable or no member
   *         details are required
   */
  T getMemberHoldingTypeDetails();
}