persistentstore.java

hsqldb是100％java实现的数据库,是一个开放源代码的JAVA数据库 l 具有标准的SQL语法和JAVA接口 l HSQLDB可以自由使用和分发 l 非常简洁和快速的

/* Copyright (c) 2001-2005, The HSQL Development Group
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 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
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package org.hsqldb.persist;

import java.io.IOException;

import org.hsqldb.rowio.RowInputInterface;

/**
 * Interface for a store for CachedObject object.
 *
 * @author fredt@users
 * @version 1.8.0
 * @since 1.8.0
 */
public interface PersistentStore {

    int INT_STORE_SIZE  = 4;
    int LONG_STORE_SIZE = 8;

    /** get object */
    CachedObject get(int key);

    /** get object, ensuring future gets will return the same instance of the object */
    CachedObject getKeep(int key);

    int getStorageSize(int key);

    /** add new object */
    void add(CachedObject object) throws IOException;

    /** add object previously removed from persistnce */
    void restore(CachedObject object) throws IOException;

    CachedObject get(RowInputInterface in) throws IOException;

    CachedObject getNewInstance(int size) throws IOException;

    /** remove the persisted image but not the cached copy */
    void removePersistence(int i);

    /** remove both persisted and cached copies */
    void remove(int i);

    /** remove the cached copies */
    void release(int i);

    /** commit persisted image */
    void commit(CachedObject object);
}