/*==========================================================================*\
| $Id: PreviewingResultSet.java,v 1.1 2010/05/11 15:52:46 aallowat Exp $
|*-------------------------------------------------------------------------*|
| Copyright (C) 2006-2008 Virginia Tech
|
| This file is part of Web-CAT.
|
| Web-CAT is free software; you can redistribute it and/or modify
| it under the terms of the GNU Affero General Public License as published
| by the Free Software Foundation; either version 3 of the License, or
| (at your option) any later version.
|
| Web-CAT 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 for more details.
|
| You should have received a copy of the GNU Affero General Public License
| along with Web-CAT; if not, see <http://www.gnu.org/licenses/>.
\*==========================================================================*/
package org.webcat.oda.designer.preview;
import java.math.BigDecimal;
import java.sql.Timestamp;
import org.webcat.oda.commons.IWebCATResultSet;
import org.webcat.oda.commons.WebCATDataException;
import org.webcat.oda.designer.DesignerActivator;
//------------------------------------------------------------------------
/**
* TODO: real description
*
* @author Tony Allevato (Virginia Tech Computer Science)
* @version $Id: PreviewingResultSet.java,v 1.1 2010/05/11 15:52:46 aallowat Exp $
*/
public class PreviewingResultSet implements IWebCATResultSet
{
// === Methods ============================================================
// ------------------------------------------------------------------------
/**
* Creates a new instance of the PreviewingResultSet class.
*
* @param uuid
* @param maxRecords
*/
public PreviewingResultSet(String uuid, int maxRecords)
{
this.uuid = uuid;
this.maxRecords = maxRecords;
currentRow = 0;
}
private PreviewingResultCache previewCache()
{
if (previewCache == null)
{
// Try again to get the previewing cache. This might fail and
// return null if the user hasn't set the server URL in the
// preferences yet.
previewCache = DesignerActivator.getDefault().getPreviewCache();
}
return previewCache;
}
public void prepare(String entityType, String[] expressions)
throws WebCATDataException
{
this.entityType = entityType;
this.expressions = expressions;
}
public void execute() throws WebCATDataException
{
PreviewingResultCache cache = previewCache();
if (cache != null)
{
cache.ensureResultsAreCached(uuid, entityType, expressions, true);
recordCount = cache.getRowCount(uuid);
}
else
{
recordCount = 0;
}
currentRow = -1;
}
public void close() throws WebCATDataException
{
// Do nothing.
}
public boolean moveToNextRow() throws WebCATDataException
{
if (currentRow < rowCount() - 1)
{
currentRow++;
return true;
}
else
{
return false;
}
}
public int currentRow() throws WebCATDataException
{
return currentRow;
}
public Object currentRowValueAtIndex(int columnIndex)
{
PreviewingResultCache cache = previewCache();
if (cache != null)
{
cache.ensureResultsAreCached(uuid, entityType, expressions, true);
return cache.getValue(uuid, currentRow, columnIndex);
}
else
{
return null;
}
}
public boolean booleanValueAtIndex(int columnIndex)
throws WebCATDataException
{
Object value = currentRowValueAtIndex(columnIndex);
if (value == null)
{
wasValueNull = true;
return false;
}
else
{
wasValueNull = false;
if (value instanceof Boolean)
return ((Boolean) value).booleanValue();
else
return Boolean.parseBoolean(value.toString());
}
}
public Timestamp timestampValueAtIndex(int columnIndex)
throws WebCATDataException
{
Object value = currentRowValueAtIndex(columnIndex);
if (value == null)
{
wasValueNull = true;
return new Timestamp(0);
}
else
{
wasValueNull = false;
if (value instanceof Timestamp)
{
return (Timestamp) value;
}
else
{
try
{
return new Timestamp(Long.parseLong(value.toString()));
}
catch (NumberFormatException e)
{
throw formatException(columnIndex, value, "Timestamp");
}
}
}
}
public BigDecimal decimalValueAtIndex(int columnIndex)
throws WebCATDataException
{
Object value = currentRowValueAtIndex(columnIndex);
if (value == null)
{
wasValueNull = true;
return BigDecimal.ZERO;
}
else
{
wasValueNull = false;
if (value instanceof BigDecimal)
{
return (BigDecimal) value;
}
else
{
try
{
return new BigDecimal(value.toString());
}
catch (NumberFormatException e)
{
throw formatException(columnIndex, value, "Decimal");
}
}
}
}
public double doubleValueAtIndex(int columnIndex)
throws WebCATDataException
{
Object value = currentRowValueAtIndex(columnIndex);
if (value == null)
{
wasValueNull = true;
return 0;
}
else
{
wasValueNull = false;
if (value instanceof Number)
{
return ((Number) value).doubleValue();
}
else
{
try
{
return Double.parseDouble(value.toString());
}
catch (NumberFormatException e)
{
throw formatException(columnIndex, value, "Float");
}
}
}
}
public int intValueAtIndex(int columnIndex) throws WebCATDataException
{
Object value = currentRowValueAtIndex(columnIndex);
if (value == null)
{
wasValueNull = true;
return 0;
}
else
{
wasValueNull = false;
if (value instanceof Number)
return ((Number) value).intValue();
else
{
// Try to parse the string as an integer. If this fails (for
// example, if it's a floating point value), then try it as a
// double and take the floor.
try
{
return Integer.parseInt(value.toString());
}
catch (NumberFormatException e)
{
try
{
return (int) Double.parseDouble(value.toString());
}
catch (IllegalArgumentException e2)
{
throw formatException(columnIndex, value, "Integer");
}
}
}
}
}
public String stringValueAtIndex(int columnIndex)
throws WebCATDataException
{
Object value = currentRowValueAtIndex(columnIndex);
if (value == null)
{
wasValueNull = true;
return "";
}
else
{
wasValueNull = false;
if (value instanceof String)
return (String) value;
else
return value.toString();
}
}
public boolean wasValueNull() throws WebCATDataException
{
return wasValueNull;
}
private int rowCount()
{
return Math.min(recordCount, maxRecords);
}
private IllegalArgumentException formatException(int columnIndex,
Object value, String destinationType)
{
return new IllegalArgumentException(
"The result (\"" + value.toString() +
"\") of the expression [ " + expressions[columnIndex] +
" ] could not be converted " +
"to type " + destinationType + ".");
}
// === Instance Variables =================================================
private String uuid;
private int maxRecords;
private int recordCount;
private int currentRow;
private String entityType;
private String[] expressions;
private boolean wasValueNull;
private PreviewingResultCache previewCache;
}