Quadcap Embeddable Database

com/quadcap/sql/InsertBlob.java

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package com.quadcap.sql;

/* Copyright 1999 - 2003 Quadcap Software.  All rights reserved.
 *
 * This software is distributed under the Quadcap Free Software License.
 * This software may be used or modified for any purpose, personal or
 * commercial.  Open Source redistributions are permitted.  Commercial
 * redistribution of larger works derived from, or works which bundle
 * this software requires a "Commercial Redistribution License"; see
 * http://www.quadcap.com/purchase.
 *
 * Redistributions qualify as "Open Source" under  one of the following terms:
 *   
 *    Redistributions are made at no charge beyond the reasonable cost of
 *    materials and delivery.
 *
 *    Redistributions are accompanied by a copy of the Source Code or by an
 *    irrevocable offer to provide a copy of the Source Code for up to three
 *    years at the cost of materials and delivery.  Such redistributions
 *    must allow further use, modification, and redistribution of the Source
 *    Code under substantially the same terms as this license.
 *
 * Redistributions of source code must retain the copyright notices as they
 * appear in each source code file, these license terms, and the
 * disclaimer/limitation of liability set forth as paragraph 6 below.
 *
 * Redistributions in binary form must reproduce this Copyright Notice,
 * these license terms, and the disclaimer/limitation of liability set
 * forth as paragraph 6 below, in the documentation and/or other materials
 * provided with the distribution.
 *
 * The Software is provided on an "AS IS" basis.  No warranty is
 * provided that the Software is free of defects, or fit for a
 * particular purpose.  
 *
 * Limitation of Liability. Quadcap Software shall not be liable
 * for any damages suffered by the Licensee or any third party resulting
 * from use of the Software.
 */

import java.io.BufferedOutputStream;
import java.io.Externalizable;
import java.io.IOException;
import java.io.InputStream;
import java.io.ObjectInput;
import java.io.ObjectOutput;
import java.io.OutputStream;

import java.sql.SQLException;

import com.quadcap.sql.io.ObjectInputStream;
import com.quadcap.sql.io.ObjectOutputStream;
import com.quadcap.sql.io.Extern;

import com.quadcap.sql.file.BlockAccess;
import com.quadcap.sql.file.BlockFile;
import com.quadcap.sql.file.Datafile;
import com.quadcap.sql.file.Log;
import com.quadcap.sql.file.PageManager;
import com.quadcap.sql.file.SubPageManager;

import com.quadcap.sql.types.Value;
import com.quadcap.sql.types.ValueBlob;

import com.quadcap.util.Debug;

import com.quadcap.io.IO;
 
/**
 * Log step to insert a BLOB value into the database.
 *
 * @author Stan Bailes
 */
public class InsertBlob extends LogStep implements Externalizable {
    long                                tempBlock;
    long                                permBlock;

    /**
     * Default constructor for serialization
     */
    public InsertBlob() {}

    /**
     * Construct InsertBlob for a given blob
     */
    public InsertBlob(Session session, ValueBlob blob)
        throws IOException
    {
        super(session);

        if (blob.getBytesVal() != null) {
            blob.passivate(session.getDatabase(), session.getTransactionId());
        }
        this.tempBlock = blob.getTempBlock();
        this.permBlock = blob.getPermBlock();
    }

    /**
     * LogStep.redo():
     */
    public void redo(Session session) throws IOException, SQLException {
        Log log = session.getLog();
        if (session.getConnection().inRecovery() && tempBlock >= 0) {
            BlockFile perm = session.getFile();
            BlockFile temp = session.getDatabase().getTempFile();
            InputStream is = temp.getInputStream(tempBlock);

            long newPermBlock = perm.newPage();
            OutputStream os = perm.getOutputStream(newPermBlock);
            IO.copyStream(is, os);
            os.close();
            is.close();

            log.putRowMap(permBlock, newPermBlock);
            permBlock = newPermBlock;
        }       
        session.getDatabase().addMorgue(permBlock, session.getTransactionId());
    }

    public void undo(Session session) throws IOException, SQLException {
        final Database db = session.getDatabase();
        final BlockFile file = session.getFile();

        file.freeStream(permBlock);
        db.delMorgue(permBlock);
    }

    public void prepare(Session session) throws IOException {
    }
    
    public void readExternal(ObjectInput in)
        throws IOException, ClassNotFoundException
    {
        super.readExternal(in);
        tempBlock = in.readLong();
        permBlock = in.readLong();
    }
    
    public void writeExternal(ObjectOutput out) throws IOException {
        super.writeExternal(out);
        out.writeLong(tempBlock);
        out.writeLong(permBlock);
    }

    //#ifdef DEBUG
    public String toString() {
        StringBuffer sb = new StringBuffer(super.toString());
        sb.append(" InsertBlob(");
        sb.append(Long.toString(tempBlock));
        sb.append(',');
        sb.append(Long.toString(permBlock));
        sb.append(')');
        return sb.toString();
    }
    //#endif

    static Extern extern;
    public void setExtern(Extern extern) { InsertBlob.extern = extern; }
    public Extern getExtern() { return extern; }

    public void discard(Datafile db) throws IOException {
        db.getTempFile(false).freeSegment(tempBlock);
        db.releaseTempFile();   // Release refcount obtained when the blob was created
    }
}