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A full SQL database system with JDBC driver that can be embedded in a Java application or operate as a stand-alone server with clients connecting via TCP/IP.
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/**
 * com.mckoi.database.GTPrivMapDataSource  26 Aug 2002
 *
 * Mckoi SQL Database ( http://www.mckoi.com/database )
 * Copyright (C) 2000, 2001, 2002  Diehl and Associates, Inc.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * Version 2 as published by the Free Software Foundation.
 *
 * This program 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 General Public License Version 2 for more details.
 *
 * You should have received a copy of the GNU General Public License
 * Version 2 along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 *
 * Change Log:
 * 
 * 
 */

package com.mckoi.database;

import java.util.ArrayList;
import com.mckoi.util.BigNumber;

/**
 * A GTDataSource that maps a Privs 11-bit set to strings that represent the
 * priv in human understandable string.  Each 11-bit priv set contains 12
 * entries for each bit that was set.
 * 
 * This table provides a convenient way to join the system grant table and
 * 'expand' the privs that are allowed though it.
 *
 * @author Tobias Downer
 */

public class GTPrivMapDataSource extends GTDataSource {

  /**
   * Number of bits.
   */
  private static int BIT_COUNT = Privileges.BIT_COUNT;
  
  
  /**
   * Constructor.
   */
  public GTPrivMapDataSource(DatabaseConnection connection) {
    super(connection.getSystem());
  }
  
  // ---------- Implemented from GTDataSource ----------
  
  public DataTableDef getDataTableDef() {
    return DEF_DATA_TABLE_DEF;
  }
  
  public int getRowCount() {
    return (1 << BIT_COUNT) * BIT_COUNT;
  }

  public TObject getCellContents(final int column, final int row) {
    int c1 = row / BIT_COUNT;
    if (column == 0) {
      return columnValue(column, BigNumber.fromInt(c1));
    }
    else {
      int priv_bit = (1 << (row % BIT_COUNT));
      String priv_string = null;
      if ((c1 & priv_bit) != 0) {
        priv_string = Privileges.formatPriv(priv_bit);
      }
      return columnValue(column, priv_string);
    }
  }

  // ---------- Overwritten from GTDataSource ----------
  
  public SelectableScheme getColumnScheme(int column) {
    if (column == 0) {
      return new PrivMapSearch(this, column);
    }
    else {
      return new BlindSearch(this, column);
    }
  }
  
  // ---------- Static ----------

  /**
   * The data table def that describes this table of data source.
   */
  static final DataTableDef DEF_DATA_TABLE_DEF;

  static {

    DataTableDef def = new DataTableDef();
    def.setTableName(
             new TableName(Database.SYSTEM_SCHEMA, "sUSRPrivMap"));

    // Add column definitions
    def.addColumn(numericColumn("priv_bit"));
    def.addColumn( stringColumn("description"));

    // Set to immutable
    def.setImmutable();

    DEF_DATA_TABLE_DEF = def;

  }

  // ---------- Inner classes ----------
  
  /**
   * A SelectableScheme that makes searching on the 'priv_bit' column a lot
   * less painless!
   */
  private static final class PrivMapSearch extends CollatedBaseSearch {
    
    PrivMapSearch(TableDataSource table, int column) {
      super(table, column);
    }

    public SelectableScheme copy(TableDataSource table, boolean immutable) {
      // Return a fresh object.  This implementation has no state so we can
      // ignore the 'immutable' flag.
      return new BlindSearch(table, getColumn());
    }
    
    protected int searchFirst(TObject val) {
      if (val.isNull()) {
        return -1;
      }

      int num = ((BigNumber) val.getObject()).intValue();

      if (num < 0) {
        return -1;
      }
      else if (num > (1 << BIT_COUNT)) {
        return -(((1 << BIT_COUNT) * BIT_COUNT) + 1);
      }

      return (num * BIT_COUNT);
    }

    protected int searchLast(TObject val) {
      int p = searchFirst(val);
      if (p >= 0) {
        return p + (BIT_COUNT - 1);
      }
      else {
        return p;
      }
    }
    
  }
  
}