// Copyright 2004, 2005 The Apache Software Foundation
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package org.apache.tapestry.contrib.table.components;
import java.util.Iterator;
import java.util.Map;
import org.apache.tapestry.IRequestCycle;
import org.apache.tapestry.contrib.table.model.IPrimaryKeyConvertor;
/**
* A low level Table component that generates the rows of the current page in the table.
*
* This component is a variant of {@link org.apache.tapestry.contrib.table.components.TablePages},
* but is designed for operation in a form. The displayed rows are stored in
* hidden form fields, which are then read during a rewind. This ensures that
* the form will rewind in exactly the same was as it was rendered even if the
* TableModel has changed and no StaleLink exceptions will occur.
*
* The component must be wrapped by {@link org.apache.tapestry.contrib.table.components.TableView}.
*
* <p>
* The component iterates over the rows of the current page in the table.
* The rows are wrapped in 'tr' tags by default.
* You can define columns manually within, or
* you can use {@link org.apache.tapestry.contrib.table.components.TableValues}
* to generate the columns automatically.
* <p>
* Please see the Component Reference for details on how to use this component.
*
* [<a href="../../../../../../../ComponentReference/contrib.TableFormRows.html">Component Reference</a>]
*
* @author mindbridge
*
*/
public abstract class TableFormRows extends TableRows
{
public abstract IPrimaryKeyConvertor getConvertor();
public abstract IPrimaryKeyConvertor getConvertorCache();
public abstract void setConvertorCache(IPrimaryKeyConvertor convertor);
public abstract Map getConvertedValues();
/**
* Returns the PK convertor cached within the realm of the current request cycle.
*
* @return the cached PK convertor
*/
public IPrimaryKeyConvertor getCachedConvertor()
{
IPrimaryKeyConvertor objConvertor = getConvertorCache();
if (objConvertor == null) {
objConvertor = getConvertor();
setConvertorCache(objConvertor);
}
return objConvertor;
}
/**
* Get the list of all table rows to be displayed on this page, converted
* using the PK.convertor.
*
* @return an iterator of all converted table rows
*/
public Iterator getConvertedTableRowsIterator()
{
final Iterator objTableRowsIterator = getTableRowsIterator();
final IPrimaryKeyConvertor objConvertor = getCachedConvertor();
if (objConvertor == null)
return objTableRowsIterator;
return new Iterator()
{
public boolean hasNext()
{
return objTableRowsIterator.hasNext();
}
public Object next()
{
Object objValue = objTableRowsIterator.next();
Object objPrimaryKey = objConvertor.getPrimaryKey(objValue);
Map mapConvertedValues = getConvertedValues();
mapConvertedValues.put(objPrimaryKey, objValue);
return objPrimaryKey;
}
public void remove()
{
objTableRowsIterator.remove();
}
};
}
/**
* Sets the current table row PK and invokes {@link #setTableRow(Object)} as a result.
* This method is for internal use only.
*
* @param objConvertedTableRow The current converted table row (PK)
*/
public void setConvertedTableRow(Object objConvertedTableRow)
{
Object objValue = objConvertedTableRow;
IPrimaryKeyConvertor objConvertor = getCachedConvertor();
if (objConvertor != null) {
IRequestCycle objCycle = getPage().getRequestCycle();
if (objCycle.isRewinding()) {
objValue = objConvertor.getValue(objConvertedTableRow);
}
else {
Map mapConvertedValues = getConvertedValues();
objValue = mapConvertedValues.get(objConvertedTableRow);
}
}
setTableRow(objValue);
}
}