package org.litesoft.orsup.base;

import org.litesoft.orsup.selection.*;
import org.litesoft.util.*;

/**
 * An inpliementation of a PersistentObjectUniqueKey that is PO Instance/Identity based for those POs that do NOT have a Unique Key
 */
public class PersistentObjectUniqueKeyForInstance extends PersistentObjectUniqueKey
{
    transient private PersistentObject<?> mPersistentObject;
    private int mPOsystemHashCode;

    public PersistentObjectUniqueKeyForInstance( PersistentObject<?> pPersistentObject )
    {
        Utils.assertNotNull( "PersistentObject", mPersistentObject = pPersistentObject );
        mPOsystemHashCode = System.identityHashCode( mPersistentObject );
    }

    protected int calcHashCode()
    {
        return mPOsystemHashCode;
    }

    protected boolean equalsNotNullNotUs( PersistentObjectUniqueKey pThem )
    {
        if ( pThem instanceof PersistentObjectUniqueKeyForInstance )
        {
            PersistentObjectUniqueKeyForInstance them = (PersistentObjectUniqueKeyForInstance) pThem;
            if ( this.mPOsystemHashCode == them.mPOsystemHashCode )
            {
                if ( (this.mPersistentObject == null) || (them.mPersistentObject == null) ||
                     (this.mPersistentObject == them.mPersistentObject) )
                {
                    return true;
                }
            }
        }
        return false;
    }

    protected String generateToStringForConstructor()
    {
        return null;  // ? Should this throw an exception?
    }

    public WhereClause convertToWC()
    {
        throw new IllegalStateException(
                "Attempt to query on a PersistentObjectUniqueKey for an object that has no PersistentObjectUniqueKey" );
    }
}