tapestry-core/src/main/java/org/apache/tapestry5/corelib/components/GridRows.java - tapestry-5 - Git at Google

 // 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.
 // Copyright 2007, 2008 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.tapestry5.corelib.components;

 import org.apache.tapestry5.ComponentAction;
 import org.apache.tapestry5.MarkupWriter;
 import org.apache.tapestry5.PropertyOverrides;
 import org.apache.tapestry5.ValueEncoder;
 import org.apache.tapestry5.annotations.Environmental;
 import org.apache.tapestry5.annotations.Parameter;
 import org.apache.tapestry5.annotations.Property;
 import org.apache.tapestry5.beaneditor.PropertyModel;
 import org.apache.tapestry5.grid.GridDataSource;
 import org.apache.tapestry5.grid.GridModel;
 import org.apache.tapestry5.services.FormSupport;

 import java.util.List;

 /**
  * Renders out a series of rows within the table.
  *
  * Inside a {@link Form}, a series of row index numbers are stored into the form
  * ( {@linkplain FormSupport#store(Object, ComponentAction) as
  * ComponentActions}). This can be a problem in situations where the data set
  * can shift between the form render and the form submission, with a risk of
  * applying changes to the wrong objects.
  *
  * For this reason, when using GridRows inside a Form, you should generally
  * provide a {@link org.apache.tapestry5.ValueEncoder} (via the encoder
  * parameter), or use an entity type for the "row" parameter for which
  * Tapestry can provide a ValueEncoder automatically. This will allow Tapestry
  * to use a unique ID for each row that doesn't change when rows are reordered.
  *
  * @tapestrydoc
  */
 @SuppressWarnings({"unchecked"})
 public class GridRows
 {
     private int startRow;

     private boolean recordStateByIndex;

     private boolean recordStateByEncoder;

     /**
      * This action is used when a {@link org.apache.tapestry5.ValueEncoder} is not provided.
      */
     static class SetupForRowByIndex implements ComponentAction<GridRows>
     {
         private static final long serialVersionUID = -3216282071752371975L;

         private final int rowIndex;

         public SetupForRowByIndex(int rowIndex)
         {
             this.rowIndex = rowIndex;
         }

         public void execute(GridRows component)
         {
             component.setupForRow(rowIndex);
         }

         @Override
         public String toString()
         {
             return String.format("GridRows.SetupForRowByIndex[%d]", rowIndex);
         }
     }

     /**
      * This action is used when a {@link org.apache.tapestry5.ValueEncoder} is provided.
      */
     static class SetupForRowWithClientValue implements ComponentAction<GridRows>
     {
         private final String clientValue;

         SetupForRowWithClientValue(String clientValue)
         {
             this.clientValue = clientValue;
         }

         public void execute(GridRows component)
         {
             component.setupForRowWithClientValue(clientValue);
         }

         @Override
         public String toString()
         {
             return String.format("GridRows.SetupForRowWithClientValue[%s]", clientValue);
         }
     }

     /**
      * Parameter used to set the CSS class for each row (each &lt;tr&gt; element) within the &lt;tbody&gt;). This is not
      * cached, so it will be recomputed for each row.
      */
     @Parameter(cache = false)
     private String rowClass;

     /**
      * Object that provides access to the bean and data models used to render the Grid.
      */
     @Parameter(value = "componentResources.container")
     private GridModel gridModel;

     /**
      * Where to search for property override blocks.
      */
     @Parameter(required = true, allowNull = false)
     @Property
     private PropertyOverrides overrides;

     /**
      * Number of rows displayed on each page. Long result sets are split across multiple pages.
      */
     @Parameter(required = true)
     private int rowsPerPage;

     /**
      * The current page number within the available pages (indexed from 1).
      */
     @Parameter(required = true)
     private int currentPage;

     /**
      * The current row being rendered, this is primarily an output parameter used to allow the Grid, and the Grid's
      * container, to know what object is being rendered.
      */
     @Parameter(required = true)
     @Property(write = false)
     private Object row;

     /**
      * If true, then the CSS class on each &lt;TD&gt; cell will be omitted, which can reduce the amount of output from
      * the component overall by a considerable amount. Leave this as false, the default, when you are leveraging the CSS
      * to customize the look and feel of particular columns.
      */
     @Parameter
     private boolean lean;

     /**
      * If true and the component is enclosed by a Form, then the normal state saving logic is turned off. Defaults to
      * false, enabling state saving logic within Forms. This can be set to false when form elements within the Grid are
      * not related to the current row of the grid, or where another component (such as {@link
      * org.apache.tapestry5.corelib.components.Hidden}) is used to maintain row state.
      */
     @Parameter(name = "volatile")
     private boolean volatileState;

     /**
      * A ValueEncoder used to convert server-side objects (provided by the
      * "row" parameter) into unique client-side strings (typically IDs) and
      * back. In general, when using Grid and Form together, you should either
      * provide the encoder parameter or use a "row" type for which Tapestry is
      * configured to provide a ValueEncoder automatically. Otherwise Tapestry
      * must fall back to using the plain index of each row, rather
      * than the ValueEncoder-provided unique ID, for recording state into the
      * form.
      */
     @Parameter
     private ValueEncoder encoder;


     /**
      * Optional output parameter (only set during rendering) that identifies the current row index. This is the index on
      * the page (i.e., always numbered from zero) as opposed to the row index inside the {@link
      * org.apache.tapestry5.grid.GridDataSource}.
      */
     @Parameter
     private int rowIndex;

     /**
      * Optional output parameter that stores the current column index.
      */
     @Parameter
     @Property
     private int columnIndex;

     @Environmental(false)
     private FormSupport formSupport;


     private int endRow;

     /**
      * Index into the {@link org.apache.tapestry5.grid.GridDataSource}.
      */
     private int dataRowIndex;

     private String propertyName;

     @Property(write = false)
     private PropertyModel columnModel;

     void onBeginRenderFromRow(MarkupWriter writer)
     {

         if (dataRowIndex == startRow)
         {
             writer.attributes("data-grid-row", "first");
         }

         if (dataRowIndex == endRow)
         {
             writer.attributes("data-grid-row", "last");
         }

         // Not a cached parameter, so careful to only access it once.

         String rc = rowClass;

         if (rc != null)
         {
             writer.attributes("class", rc);
         }
     }

     void onBeginRenderFromColumn(MarkupWriter writer)
     {

         String id = gridModel.getDataModel().get(propertyName).getId();

         if (!lean)
         {
             writer.attributes("data-grid-property", id);
         }

         switch (gridModel.getSortModel().getColumnSort(id))
         {
             case ASCENDING:
                 writer.attributes("data-grid-column-sort", "ascending");
                 break;

             case DESCENDING:
                 writer.attributes("data-grid-column-sort", "descending");
                 break;

             default:
         }
     }

     void setupRender()
     {
         GridDataSource dataSource = gridModel.getDataSource();

         int numberOfRowsRequiredToShowCurrentPage = 1 + (currentPage - 1) * rowsPerPage;
         int numberOfRowsRequiredToFillCurrentPage = currentPage * rowsPerPage;

         int availableRowsWithLimit = dataSource.getAvailableRows(numberOfRowsRequiredToFillCurrentPage);

         // This can sometimes happen when the number of items shifts between requests.

         if (numberOfRowsRequiredToShowCurrentPage > availableRowsWithLimit)
         {
             int maxPages = ((availableRowsWithLimit - 1) / rowsPerPage) + 1;
             currentPage = maxPages;
         }
         startRow = (currentPage - 1) * rowsPerPage;
         endRow = Math.min(availableRowsWithLimit - 1, startRow + rowsPerPage - 1);

         dataRowIndex = startRow;

         boolean recordingStateInsideForm = !volatileState && formSupport != null;

         recordStateByIndex = recordingStateInsideForm && (encoder == null);
         recordStateByEncoder = recordingStateInsideForm && (encoder != null);
     }

     /**
      * Callback method, used when recording state to a form, or called directly when not recording state.
      */
     void setupForRow(int rowIndex)
     {
         row = gridModel.getDataSource().getRowValue(rowIndex);
     }

     /**
      * Callback method that bypasses the data source and converts a primary key back into a row value (via {@link
      * org.apache.tapestry5.ValueEncoder#toValue(String)}).
      */
     void setupForRowWithClientValue(String clientValue)
     {
         row = encoder.toValue(clientValue);

         if (row == null)
             throw new IllegalArgumentException(
                     String.format("%s returned null for client value '%s'.", encoder, clientValue));
     }


     boolean beginRender()
     {
         // Setup for this row.

         setupForRow(dataRowIndex);

         // Update the index parameter (which starts from zero).
         rowIndex = dataRowIndex - startRow;


         if (row != null)
         {
             // When needed, store a callback used when the form is submitted.

             if (recordStateByIndex)
                 formSupport.store(this, new SetupForRowByIndex(dataRowIndex));

             if (recordStateByEncoder)
             {
                 String key = encoder.toClient(row);
                 formSupport.store(this, new SetupForRowWithClientValue(key));
             }
         }

         // If the row is null, it's because the rowIndex is too large (see the notes
         // on GridDataSource).  When row is null, return false to not render anything for this iteration
         // of the loop.

         return row != null;
     }

     boolean afterRender()
     {
         dataRowIndex++;

         // Abort the loop when we hit a null row, or when we've exhausted the range we need to
         // display.

         return row == null || dataRowIndex > endRow;
     }

     public List<String> getPropertyNames()
     {
         return gridModel.getDataModel().getPropertyNames();
     }

     public String getPropertyName()
     {
         return propertyName;
     }

     public void setPropertyName(String propertyName)
     {
         this.propertyName = propertyName;

         columnModel = gridModel.getDataModel().get(propertyName);
     }
 }
	// 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.
	// Copyright 2007, 2008 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.tapestry5.corelib.components;

	import org.apache.tapestry5.ComponentAction;
	import org.apache.tapestry5.MarkupWriter;
	import org.apache.tapestry5.PropertyOverrides;
	import org.apache.tapestry5.ValueEncoder;
	import org.apache.tapestry5.annotations.Environmental;
	import org.apache.tapestry5.annotations.Parameter;
	import org.apache.tapestry5.annotations.Property;
	import org.apache.tapestry5.beaneditor.PropertyModel;
	import org.apache.tapestry5.grid.GridDataSource;
	import org.apache.tapestry5.grid.GridModel;
	import org.apache.tapestry5.services.FormSupport;

	import java.util.List;

	/**
	* Renders out a series of rows within the table.
	*
	* Inside a {@link Form}, a series of row index numbers are stored into the form
	* ( {@linkplain FormSupport#store(Object, ComponentAction) as
	* ComponentActions}). This can be a problem in situations where the data set
	* can shift between the form render and the form submission, with a risk of
	* applying changes to the wrong objects.
	*
	* For this reason, when using GridRows inside a Form, you should generally
	* provide a {@link org.apache.tapestry5.ValueEncoder} (via the encoder
	* parameter), or use an entity type for the "row" parameter for which
	* Tapestry can provide a ValueEncoder automatically. This will allow Tapestry
	* to use a unique ID for each row that doesn't change when rows are reordered.
	*
	* @tapestrydoc
	*/
	@SuppressWarnings({"unchecked"})
	public class GridRows
	{
	private int startRow;

	private boolean recordStateByIndex;

	private boolean recordStateByEncoder;

	/**
	* This action is used when a {@link org.apache.tapestry5.ValueEncoder} is not provided.
	*/
	static class SetupForRowByIndex implements ComponentAction<GridRows>
	{
	private static final long serialVersionUID = -3216282071752371975L;

	private final int rowIndex;

	public SetupForRowByIndex(int rowIndex)
	{
	this.rowIndex = rowIndex;
	}

	public void execute(GridRows component)
	{
	component.setupForRow(rowIndex);
	}

	@Override
	public String toString()
	{
	return String.format("GridRows.SetupForRowByIndex[%d]", rowIndex);
	}
	}

	/**
	* This action is used when a {@link org.apache.tapestry5.ValueEncoder} is provided.
	*/
	static class SetupForRowWithClientValue implements ComponentAction<GridRows>
	{
	private final String clientValue;

	SetupForRowWithClientValue(String clientValue)
	{
	this.clientValue = clientValue;
	}

	public void execute(GridRows component)
	{
	component.setupForRowWithClientValue(clientValue);
	}

	@Override
	public String toString()
	{
	return String.format("GridRows.SetupForRowWithClientValue[%s]", clientValue);
	}
	}

	/**
	* Parameter used to set the CSS class for each row (each <tr> element) within the <tbody>). This is not
	* cached, so it will be recomputed for each row.
	*/
	@Parameter(cache = false)
	private String rowClass;

	/**
	* Object that provides access to the bean and data models used to render the Grid.
	*/
	@Parameter(value = "componentResources.container")
	private GridModel gridModel;

	/**
	* Where to search for property override blocks.
	*/
	@Parameter(required = true, allowNull = false)
	@Property
	private PropertyOverrides overrides;

	/**
	* Number of rows displayed on each page. Long result sets are split across multiple pages.
	*/
	@Parameter(required = true)
	private int rowsPerPage;

	/**
	* The current page number within the available pages (indexed from 1).
	*/
	@Parameter(required = true)
	private int currentPage;

	/**
	* The current row being rendered, this is primarily an output parameter used to allow the Grid, and the Grid's
	* container, to know what object is being rendered.
	*/
	@Parameter(required = true)
	@Property(write = false)
	private Object row;

	/**
	* If true, then the CSS class on each <TD> cell will be omitted, which can reduce the amount of output from
	* the component overall by a considerable amount. Leave this as false, the default, when you are leveraging the CSS
	* to customize the look and feel of particular columns.
	*/
	@Parameter
	private boolean lean;

	/**
	* If true and the component is enclosed by a Form, then the normal state saving logic is turned off. Defaults to
	* false, enabling state saving logic within Forms. This can be set to false when form elements within the Grid are
	* not related to the current row of the grid, or where another component (such as {@link
	* org.apache.tapestry5.corelib.components.Hidden}) is used to maintain row state.
	*/
	@Parameter(name = "volatile")
	private boolean volatileState;

	/**
	* A ValueEncoder used to convert server-side objects (provided by the
	* "row" parameter) into unique client-side strings (typically IDs) and
	* back. In general, when using Grid and Form together, you should either
	* provide the encoder parameter or use a "row" type for which Tapestry is
	* configured to provide a ValueEncoder automatically. Otherwise Tapestry
	* must fall back to using the plain index of each row, rather
	* than the ValueEncoder-provided unique ID, for recording state into the
	* form.
	*/
	@Parameter
	private ValueEncoder encoder;


	/**
	* Optional output parameter (only set during rendering) that identifies the current row index. This is the index on
	* the page (i.e., always numbered from zero) as opposed to the row index inside the {@link
	* org.apache.tapestry5.grid.GridDataSource}.
	*/
	@Parameter
	private int rowIndex;

	/**
	* Optional output parameter that stores the current column index.
	*/
	@Parameter
	@Property
	private int columnIndex;

	@Environmental(false)
	private FormSupport formSupport;


	private int endRow;

	/**
	* Index into the {@link org.apache.tapestry5.grid.GridDataSource}.
	*/
	private int dataRowIndex;

	private String propertyName;

	@Property(write = false)
	private PropertyModel columnModel;

	void onBeginRenderFromRow(MarkupWriter writer)
	{

	if (dataRowIndex == startRow)
	{
	writer.attributes("data-grid-row", "first");
	}

	if (dataRowIndex == endRow)
	{
	writer.attributes("data-grid-row", "last");
	}

	// Not a cached parameter, so careful to only access it once.

	String rc = rowClass;

	if (rc != null)
	{
	writer.attributes("class", rc);
	}
	}

	void onBeginRenderFromColumn(MarkupWriter writer)
	{

	String id = gridModel.getDataModel().get(propertyName).getId();

	if (!lean)
	{
	writer.attributes("data-grid-property", id);
	}

	switch (gridModel.getSortModel().getColumnSort(id))
	{
	case ASCENDING:
	writer.attributes("data-grid-column-sort", "ascending");
	break;

	case DESCENDING:
	writer.attributes("data-grid-column-sort", "descending");
	break;

	default:
	}
	}

	void setupRender()
	{
	GridDataSource dataSource = gridModel.getDataSource();

	int numberOfRowsRequiredToShowCurrentPage = 1 + (currentPage - 1) * rowsPerPage;
	int numberOfRowsRequiredToFillCurrentPage = currentPage * rowsPerPage;

	int availableRowsWithLimit = dataSource.getAvailableRows(numberOfRowsRequiredToFillCurrentPage);

	// This can sometimes happen when the number of items shifts between requests.

	if (numberOfRowsRequiredToShowCurrentPage > availableRowsWithLimit)
	{
	int maxPages = ((availableRowsWithLimit - 1) / rowsPerPage) + 1;
	currentPage = maxPages;
	}
	startRow = (currentPage - 1) * rowsPerPage;
	endRow = Math.min(availableRowsWithLimit - 1, startRow + rowsPerPage - 1);

	dataRowIndex = startRow;

	boolean recordingStateInsideForm = !volatileState && formSupport != null;

	recordStateByIndex = recordingStateInsideForm && (encoder == null);
	recordStateByEncoder = recordingStateInsideForm && (encoder != null);
	}

	/**
	* Callback method, used when recording state to a form, or called directly when not recording state.
	*/
	void setupForRow(int rowIndex)
	{
	row = gridModel.getDataSource().getRowValue(rowIndex);
	}

	/**
	* Callback method that bypasses the data source and converts a primary key back into a row value (via {@link
	* org.apache.tapestry5.ValueEncoder#toValue(String)}).
	*/
	void setupForRowWithClientValue(String clientValue)
	{
	row = encoder.toValue(clientValue);

	if (row == null)
	throw new IllegalArgumentException(
	String.format("%s returned null for client value '%s'.", encoder, clientValue));
	}


	boolean beginRender()
	{
	// Setup for this row.

	setupForRow(dataRowIndex);

	// Update the index parameter (which starts from zero).
	rowIndex = dataRowIndex - startRow;


	if (row != null)
	{
	// When needed, store a callback used when the form is submitted.

	if (recordStateByIndex)
	formSupport.store(this, new SetupForRowByIndex(dataRowIndex));

	if (recordStateByEncoder)
	{
	String key = encoder.toClient(row);
	formSupport.store(this, new SetupForRowWithClientValue(key));
	}
	}

	// If the row is null, it's because the rowIndex is too large (see the notes
	// on GridDataSource). When row is null, return false to not render anything for this iteration
	// of the loop.

	return row != null;
	}

	boolean afterRender()
	{
	dataRowIndex++;

	// Abort the loop when we hit a null row, or when we've exhausted the range we need to
	// display.

	return row == null \|\| dataRowIndex > endRow;
	}

	public List<String> getPropertyNames()
	{
	return gridModel.getDataModel().getPropertyNames();
	}

	public String getPropertyName()
	{
	return propertyName;
	}

	public void setPropertyName(String propertyName)
	{
	this.propertyName = propertyName;

	columnModel = gridModel.getDataModel().get(propertyName);
	}
	}