xmlresultset.java

数据仓库工具

/*
    Copyright (C) 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
*/

package org.webdocwf.util.xml;

import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.Reader;
import java.io.StringReader;
import java.math.BigDecimal;
import java.net.URL;
import java.sql.*;
import java.util.ArrayList;
import java.util.Map;
import java.util.Calendar;

/**
 * Class that implements JDBC ResultSet interface.
 *
 * @author     Zoran Milakovic
 */
public class XmlResultSet  implements ResultSet {

  /** Metadata for this ResultSet */
  protected ResultSetMetaData resultSetMetaData;

  /** Statement that produced this ResultSet */
  protected Statement statement;

  /** Helper class that performs the actual file reads */
  protected XmlReader reader;

  /** Table referenced by the Statement */
  protected String tableName;

  /** Array of available columns for referenced table */
  protected String[] columnNames;

  /** Array of column values for referenced table */
  protected String[] columnValues;

  protected String[] whereColumnNames;

  protected String[] whereColumnValues;


    /** Last column name index read */
    protected int lastIndexRead = -1;

    /** InputStream to keep track of */
    protected InputStream is;

  /**
   * Constructor for the XmlResultSet object
   *
   * @param statement Statement that produced this ResultSet
   * @param reader Helper class that performs the actual file reads
   * @param tableName Table referenced by the Statement
   * @param columnNames Array of available columns for referenced table
   * @param whereColumnNames is an array of column names
   * @param whereColumnValues is an array of column values
   */
  protected XmlResultSet(Statement statement, XmlReader reader , String tableName , String[] columnNames
                         , String[] whereColumnNames , String[] whereColumnValues ) {
    this.statement = statement;
    this.reader = reader;
    this.tableName = tableName;
    this.columnNames = columnNames;
    this.whereColumnNames = whereColumnNames;
    this.whereColumnValues = whereColumnValues;
  }


  public void select() throws SQLException  {
    reader.select( tableName , columnNames , whereColumnNames , whereColumnValues);
    this.rset = reader.getResultSet();
  }

  public void selectTableNames() throws SQLException {
    reader.selectTableNames();
    this.rset = reader.getResultSet();
  }
  public void close() {
  }

  private int index = 0;
  private ArrayList rset = new ArrayList();
  /**
   *Description of the Method
   *
   * @return Description of the Returned Value
   * @exception  SQLException
   * @since
   */
  public boolean next() throws SQLException {
    boolean retVal = false;
      try {
        if( !(rset.size() <= index) ) {
          this.columnValues = (String[])rset.get( index );
          index++;
          retVal = true;
        } else {
          index = 0;
          rset = new ArrayList();
          this.columnValues = new String[0];
          retVal = false;
        }
      }catch( Exception e ) { throw new SQLException("Error in ResultSet.next() : "+e.getMessage()); }
    return retVal;
  }

  public String getString(int i) throws SQLException {
    try {
      return this.columnValues[i-1].toString();
    }catch(Exception e) { throw new SQLException("Error ResultSet.getString( index ) : "+e.getMessage()); }
  }

  /**
 * Reports whether
 * the last column read had a value of SQL <code>NULL</code>.
 * Note that you must first call one of the getter methods
 * on a column to try to read its value and then call
 * the method <code>wasNull</code> to see if the value read was
 * SQL <code>NULL</code>.
 *
 * @return <code>true</code> if the last column value read was SQL
 *         <code>NULL</code> and <code>false</code> otherwise
 * @exception SQLException if a database access error occurs
 */
public boolean wasNull() throws SQLException {
    if(lastIndexRead >= 0) {
        return getString(lastIndexRead) == null;
    } else {
        throw new SQLException("No previous getter method called");
    }
}

//======================================================================
// Methods for accessing results by column index
//======================================================================


/**
 * Retrieves the value of the designated column in the current row
 * of this <code>ResultSet</code> object as
 * a <code>boolean</code> in the Java programming language.
 *
 * @param columnIndex the first column is 1, the second is 2, ...
 * @return the column value; if the value is SQL <code>NULL</code>, the
 * value returned is <code>false</code>
 * @exception SQLException if a database access error occurs
 */
public boolean getBoolean(int columnIndex) throws SQLException {
  String str = getString(columnIndex);
  return (str == null) ? false : Boolean.valueOf(str).booleanValue();
}

/**
 * Retrieves the value of the designated column in the current row
 * of this <code>ResultSet</code> object as
 * a <code>byte</code> in the Java programming language.
 *
 * @param columnIndex the first column is 1, the second is 2, ...
 * @return the column value; if the value is SQL <code>NULL</code>, the
 * value returned is <code>0</code>
 * @exception SQLException if a database access error occurs
 */
public byte getByte(int columnIndex) throws SQLException {
  String str = getString(columnIndex);
  return (str == null) ? 0 : Byte.parseByte(str);
}

/**
 * Retrieves the value of the designated column in the current row
 * of this <code>ResultSet</code> object as
 * a <code>short</code> in the Java programming language.
 *
 * @param columnIndex the first column is 1, the second is 2, ...
 * @return the column value; if the value is SQL <code>NULL</code>, the
 * value returned is <code>0</code>
 * @exception SQLException if a database access error occurs
 */
public short getShort(int columnIndex) throws SQLException {
  String str = getString(columnIndex);
  return (str == null) ? 0 : Short.parseShort(str);
}

/**
 * Gets the value of the designated column in the current row
 * of this <code>ResultSet</code> object as
 * an <code>int</code> in the Java programming language.
 *
 * @param columnIndex the first column is 1, the second is 2, ...
 * @return the column value; if the value is SQL <code>NULL</code>, the
 * value returned is <code>0</code>
 * @exception SQLException if a database access error occurs
 */
public int getInt(int columnIndex) throws SQLException {
  String str = getString(columnIndex);
  return (str == null) ? 0 : Integer.parseInt(str);
}

/**
 * Retrieves the value of the designated column in the current row
 * of this <code>ResultSet</code> object as
 * a <code>long</code> in the Java programming language.
 *
 * @param columnIndex the first column is 1, the second is 2, ...
 * @return the column value; if the value is SQL <code>NULL</code>, the
 * value returned is <code>0</code>
 * @exception SQLException if a database access error occurs
 */
public long getLong(int columnIndex) throws SQLException {
  String str = getString(columnIndex);
  return (str == null) ? 0L : Long.parseLong(str);
}

/**
 * Gets the value of the designated column in the current row
 * of this <code>ResultSet</code> object as
 * a <code>float</code> in the Java programming language.
 *
 * @param columnIndex the first column is 1, the second is 2, ...
 * @return the column value; if the value is SQL <code>NULL</code>, the
 * value returned is <code>0</code>
 * @exception SQLException if a database access error occurs
 */
public float getFloat(int columnIndex) throws SQLException {
  String str = getString(columnIndex);
  return (str == null) ? 0F : Float.parseFloat(str);
}

/**
 * Retrieves the value of the designated column in the current row
 * of this <code>ResultSet</code> object as
 * a <code>double</code> in the Java programming language.
 *
 * @param columnIndex the first column is 1, the second is 2, ...
 * @return the column value; if the value is SQL <code>NULL</code>, the
 * value returned is <code>0</code>
 * @exception SQLException if a database access error occurs
 */
public double getDouble(int columnIndex) throws SQLException {
  String str = getString(columnIndex);
  return (str == null) ? 0D : Double.parseDouble(str);
}

/**
 * Retrieves the value of the designated column in the current row
 * of this <code>ResultSet</code> object as
 * a <code>java.sql.BigDecimal</code> in the Java programming language.
 *
 * @param columnIndex the first column is 1, the second is 2, ...
 * @param scale the number of digits to the right of the decimal point
 * @return the column value; if the value is SQL <code>NULL</code>, the
 * value returned is <code>null</code>
 * @exception SQLException if a database access error occurs
 * @deprecated
 */
public BigDecimal getBigDecimal(int columnIndex, int scale)
    throws SQLException {
  // let getBigDecimal(int) handle this for now
  return getBigDecimal(columnIndex);
}

/**
 * Retrieves the value of the designated column in the current row
 * of this <code>ResultSet</code> object as
 * a <code>byte</code> array in the Java programming language.
 * The bytes represent the raw values returned by the driver.
 *
 * @param columnIndex the first column is 1, the second is 2, ...
 * @return the column value; if the value is SQL <code>NULL</code>, the
 * value returned is <code>null</code>
 * @exception SQLException if a database access error occurs
 */
public byte[] getBytes(int columnIndex) throws SQLException {
  String str = getString(columnIndex);
  return (str == null) ? null : Utils.hexStringToBytes(str);
}

/**
 * Retrieves the value of the designated column in the current row
 * of this <code>ResultSet</code> object as
 * a <code>java.sql.Date</code> object in the Java programming language.
 *
 * @param columnIndex the first column is 1, the second is 2, ...
 * @return the column value; if the value is SQL <code>NULL</code>, the
 * value returned is <code>null</code>
 * @exception SQLException if a database access error occurs
 */
public Date getDate(int columnIndex) throws SQLException  {
  String str = getString(columnIndex);
  return (str == null) ? null : Date.valueOf(str);
}

/**
 * Retrieves the value of the designated column in the current row
 * of this <code>ResultSet</code> object as
 * a <code>java.sql.Time</code> object in the Java programming language.
 *
 * @param columnIndex the first column is 1, the second is 2, ...
 * @return the column value; if the value is SQL <code>NULL</code>, the
 * value returned is <code>null</code>
 * @exception SQLException if a database access error occurs
 */
public Time getTime(int columnIndex) throws SQLException {
  String str = getString(columnIndex);
  return (str == null) ? null : Time.valueOf(str);
}

/**
 * Retrieves the value of the designated column in the current row
 * of this <code>ResultSet</code> object as a
 * <code>java.sql.Timestamp</code> object in the Java programming language.