assoc.java

这个weblogging 设计得比较精巧

/*
 * Created on Jan 13, 2004
 */
package org.roller.pojos;

import org.roller.RollerException;
import java.io.Serializable;

/**
 * Interface for hierarchical assocations.
 * @author David M Johnson
 */
public interface Assoc extends Serializable
{
    public static final String PARENT = "PARENT";
    public static final String GRANDPARENT = "GRANDPARENT";

    /** Object that owns this association. */
    public HierarchicalPersistentObject getObject();
    public void setObject(HierarchicalPersistentObject hpo);
    
    /** Associated object. */
    public HierarchicalPersistentObject getAncestor(); 
    public void setAncestor(HierarchicalPersistentObject hpo); 
    
    /** Type of relationship, PARENT or GRANDPARENT. */   
    public String getRelation();
    
    /** Save association. */
    public abstract void save() throws RollerException;
    
    /** Remove association. */
    public abstract void remove() throws RollerException;
}