Quadcap Embeddable Database

com/quadcap/sql/lock/HeldLock.java

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package com.quadcap.sql.lock;

/* 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 com.quadcap.util.Debug;

/**
 * 
 *
 * @author Stan Bailes
 */
class HeldLock extends PooledObject {
    Lock                lock;
    Transaction         trans;
    int                 mode;
    int                 waitMode;

    protected HeldLock() {}

    public void init(Transaction trans, Lock lock, int mode) {
        this.trans = trans;
        this.lock = lock;
        this.mode = mode;
        this.waitMode = mode;
    }

    final void setWaitMode(int mode) { this.waitMode = mode; }
    final int getWaitMode() { return waitMode; }
    final Transaction getTransaction() { return trans; }
    
    public final PooledObject create() { return new HeldLock(); }
    
    static int compare(HeldLock a, HeldLock b) {
        if (a == null) throw new RuntimeException("a is null");
        if (b == null) throw new RuntimeException("b is null");
        if (!a.live) throw new RuntimeException("a not live: " + a);
        if (!b.live) throw new RuntimeException("b not live: " + b);
        if (a.trans == null) throw new RuntimeException("a.trans is null");
        if (b.trans == null) throw new RuntimeException("b.trans is null");
        if (!a.trans.live) throw new RuntimeException("a trans not live: " + a);
        if (!b.trans.live) throw new RuntimeException("b trans not live: " + b);
        if (a.trans.getTransactionId()
            < b.trans.getTransactionId())
            return -1;
        if (a.trans.getTransactionId()
            > b.trans.getTransactionId())
            return 1;
        if (a.lock == null) {
            return (b.lock == null) ? 0 : -1;
        }
        if (b.lock == null) return 1;
        if (a.lock.hashCode() < b.lock.hashCode()) return -1;
        if (a.lock.hashCode() > b.lock.hashCode()) return 1;
        if (a.mode < b.mode) return -1;
        if (a.mode > b.mode) return 1;
        if (a.waitMode < b.waitMode) return -1;
        if (a.waitMode > b.waitMode) return 1;
        return 0;
    }

    public String toString() {
//          StringBuffer sb = new StringBuffer("HeldLock");
//          sb.append(super.toString());
//          sb.append(String.valueOf(trans)).append(", ");
//          sb.append(lock).append(", ");
//          sb.append(LockMode.toString(mode)).append(" (W ");
//          sb.append(LockMode.toString(waitMode)).append(")");
//          return sb.toString();
        if (lock == null) {
            return "HeldLock{}";
        } else {
            return "HeldLock{" + lock.getName() + "," +
                trans + "," + LockMode.toString(mode) + "}";
        }
    }
}