classicstore.java

用Java写的面相对象的数据库管理系统

// You can redistribute this software and/or modify it under the terms of
// the Ozone Core License version 1 published by ozone-db.org.
//
// The original code and portions created by SMB are
// Copyright (C) 1997-2000 by SMB GmbH. All rights reserved.
//
// $Id: ClassicStore.java,v 1.8 2000/10/28 16:55:17 daniela Exp $

package org.ozoneDB.core.classicStore;

import java.io.*;
import org.ozoneDB.DxLib.*;
import org.ozoneDB.*;
import org.ozoneDB.core.*;
import org.ozoneDB.util.*;


/**
 * ClassicStore acts as the mediator (director) of the classicStore module
 * especially for ClusterSpace, ObjectSpace, PersistentSpace. Currently it
 * serves only as container for the references but this should change in the
 * future to decouple class implementations.
 */
public final class ClassicStore extends Object implements Store {
    /** */
    protected Env env;
    protected ObjectSpace objectSpace;
    
    
    /** */
    public ClassicStore() {
    }
    
    
    /** */
    public void init( Env _env ) {
        env = _env;
        objectSpace = new ObjectSpace( _env );
    } 
    
    
    /** */
    public void startup() throws Exception {
        env.logWriter.newEntry( this, "startup...", LogWriter.INFO );
        objectSpace.startup();
    } 
    
    
    /** */
    public void shutdown() throws Exception {
        env.logWriter.newEntry( this, "shutdown...", LogWriter.INFO );
        objectSpace.shutdown();
    } 
    
    
    /** */
    public ObjectContainer newContainer( Transaction ta, OzoneCompatible target, ObjectID objID,
            Permissions permissions ) throws Exception {
        return objectSpace.newContainer( ta, target, objID, permissions );
    } 
    
    
    /** */
    public ObjectContainer containerForID( Transaction ta, ObjectID id ) throws Exception {
        return objectSpace.objectForID( id );
    } 
    
    
    /**
     * @param name The object name to search for.
     * @param ta
     * @return The object container for the name or null.
     */
    public ObjectContainer containerForName( Transaction ta, String name ) throws Exception {
        return objectSpace.objectForName( name );
    } 
    
    
    /**
     * @param ta
     * @param container
     * @param name
     */
    public void nameContainer( Transaction ta, ObjectContainer container, String name ) throws PermissionDeniedExc {
        try {
            objectSpace.nameObject( container, name );
        } catch (ClassicStoreExc e) {
            throw new PermissionDeniedExc( e.toString() );
        } 
    } 
    
    
    /** */
    public void join( Transaction ta, ObjectContainer container, int lockLevel ) throws Exception {
        //System.out.println ("join: " + container.id());
        ClassicObjectContainer classicCon = (ClassicObjectContainer)container;
        classicCon.upgradeLockLevel( ta, lockLevel );
        ta.idTable.addForKey( classicCon, classicCon.id() );
    } 
    
    
    /**
     * @param ta Transaction that will be commited.
     */
    public void prepareCommitTransaction( Transaction ta ) throws Exception {
        objectSpace.prepareCommitObjects( ta );
    } 
    
    
    /** */
    public void commitTransaction( Transaction ta ) {
        objectSpace.commitObjects( ta );
    } 
    
    
    /**
     * @param ta ID of the comitting transaction.
     * @param created
     * @param modified
     */
    public void abortTransaction( Transaction ta ) {
        try {
            objectSpace.abortObjects( ta );
        } catch (Exception e) {
            env.logWriter.newEntry( this, "Abort of transaction " + ta.taID() + " failed !\n" + e, LogWriter.ERROR );
        } 
    } 
    
    
    /** */
    public void upgradeLockLevel( Transaction ta, ObjectContainer container, int lockLevel ) throws Exception {
        ((ClassicObjectContainer)container).upgradeLockLevel( ta, lockLevel );
    } 
}