CachedObjectBase.java

/* Copyright (c) 2001-2014, The HSQL Development Group
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package org.hsqldb.persist;

import org.hsqldb.error.Error;
import org.hsqldb.error.ErrorCode;

public abstract class CachedObjectBase implements CachedObject {

    boolean isMemory;
    long    position;
    int     storageSize;
    boolean isInMemory;
    boolean hasChanged;
    int     keepCount;
    int     accessCount;

    public boolean isMemory() {
        return isMemory;
    }

    public void updateAccessCount(int count) {
        accessCount = count;
    }

    public int getAccessCount() {
        return accessCount;
    }

    public void setStorageSize(int size) {
        storageSize = size;
    }

    public int getStorageSize() {
        return storageSize;
    }

    final public boolean isBlock() {
        return true;
    }

    public long getPos() {
        return position;
    }

    public void setPos(long pos) {
        position = pos;
    }

    public boolean isNew() {
        return false;
    }

    public boolean hasChanged() {
        return hasChanged;
    }

    public boolean isKeepInMemory() {
        return keepCount > 0;
    }

    public boolean keepInMemory(boolean keep) {

        if (!isInMemory) {
            return false;
        }

        if (keep) {
            keepCount++;
        } else {
            keepCount--;

            if (keepCount < 0) {
                throw Error.runtimeError(ErrorCode.U_S0500,
                                         "CachedObjectBase - keep count");
            }
        }

        return true;
    }

    public boolean isInMemory() {
        return isInMemory;
    }

    public void setInMemory(boolean in) {
        isInMemory = in;
    }

    public boolean equals(Object other) {
        return other instanceof CachedObjectBase
               && ((CachedObjectBase) other).position == this.position;
    }

    public int hashCode() {
        return (int) position;
    }

    public void restore() {}

    public void destroy() {}
}