cache.java

数据仓库工具

/**
  Cache - Load data from source tables (or select statements) and puts them into
  Hatshtable (cache).

    Copyright (C) 2002-2003  Together

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
    License as published by the Free Software Foundation; either
    version 2.1 of the License, or (at your option) any later version.

    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public
    License along with this library; if not, write to the Free Software
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

 Cache.java
 Date: 23.01.2003.
 @version 1.0.0
 @author: Milosevic Sinisa [e-mail]
 */

package org.webdocwf.util.loader;


import java.util.Hashtable;
import java.util.Vector;
import java.math.BigDecimal;

/**
  Cache - Load data from source tables (or select statements) and puts them into
  Hatshtable (cache).
*/
public class Cache {

  private Hashtable hCache=null;

  /**
   * Public constructor of cache class.
   * Constructor create new hashtable
   */
  public Cache() {
    this.hCache=new Hashtable();
  }

  /**
   * Public constructor of cache class.
   * Constructor set cache table.
   * @param cache is cache table.
   */
  public Cache(Hashtable cache) {
    this.hCache=cache;
  }

  /**
   * Read current cache table
   * @return value of parmeter hCache
   */
  public Hashtable getCache() {
    return this.hCache;
  }

  /**
   * Set cache table.
   * @param cache is cache table
   */
  public void setCache(Hashtable cache) {
    this.hCache=cache;
  }

  /**
   * Put row of source values into cache.
   * @param row SQL query row
   * @param sourceValues represents source values
   */
  public void setCacheRow(BigDecimal row, Vector sourceValues) {
    this.hCache.put(row,sourceValues);
  }

  /**
   * Put row of source values into cache.
   * @param cache is cache table
   * @param row is SQL query row
   * @param sourceValues represents source values
   */
  public void setCacheRow(Hashtable cache, BigDecimal row, Vector sourceValues) {
    cache.put(row,sourceValues);
  }

  /**
   * Read row of source values.
   * @param row is SQL query row.
   * @return Vector values of source columns.
   */
  public Vector getCacheRow(BigDecimal row) {
    if(this.hCache.isEmpty())
      return null;
    else
      return (Vector)this.hCache.get(row);
  }

  /**
   * Read row of source values.
   * @param row is SQL query row.
   * @param cache is cache table
   * @return Vector values of source columns.
   */
  public Vector getCacheRow(Hashtable cache, BigDecimal row) {
    if(cache.isEmpty())
      return null;
    else
      return (Vector)cache.get(row);
  }

  /**
   * Reset cache.
   */
  public void resetCache() {
    this.hCache.clear();
    this.hCache=new Hashtable();
  }

}