javax.faces.model.ResultDataModel Maven / Gradle / Ivy
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/*
* Copyright (c) 1997, 2018 Oracle and/or its affiliates. All rights reserved.
*
* This program and the accompanying materials are made available under the
* terms of the Eclipse Public License v. 2.0, which is available at
* http://www.eclipse.org/legal/epl-2.0.
*
* This Source Code may also be made available under the following Secondary
* Licenses when the conditions for such availability set forth in the
* Eclipse Public License v. 2.0 are satisfied: GNU General Public License,
* version 2 with the GNU Classpath Exception, which is available at
* https://www.gnu.org/software/classpath/license.html.
*
* SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
*/
package javax.faces.model;
import java.util.SortedMap;
import javax.servlet.jsp.jstl.sql.Result;
/**
* ResultDataModel is a convenience implementation of
* {@link DataModel} that wraps a JSTL Result object, typically
* representing the results of executing an SQL query via JSTL tags.
*/
public class ResultDataModel extends DataModel> {
// ------------------------------------------------------------ Constructors
/**
* Construct a new {@link ResultDataModel} with no specified
* wrapped data.
*/
public ResultDataModel() {
this(null);
}
/**
* Construct a new {@link ResultDataModel} wrapping the specified
* Result.
*
* @param result Result to be wrapped (if any)
*/
public ResultDataModel(Result result) {
super();
setWrappedData(result);
}
// ------------------------------------------------------ Instance Variables
// The current row index (zero relative)
private int index = -1;
// The Result we are wrapping
private Result result = null;
// The individual rows of this Result, each represented as a Map
// with column names as keys and associated data values as values
private SortedMap rows[] = null;
// -------------------------------------------------------------- Properties
/**
* Return true if there is wrappedData
* available, and the current value of rowIndex is greater
* than or equal to zero, and less than the length of the array returned
* by calling getRows() on the underlying Result.
* Otherwise, return false.
*
* @throws javax.faces.FacesException if an error occurs getting the row availability
*/
@Override
public boolean isRowAvailable() {
if (result == null) {
return (false);
} else if ((index >= 0) && (index < rows.length)) {
return (true);
} else {
return (false);
}
}
/**
* If there is wrappedData available, return the
* length of the array returned by calling getRows()
* on the underlying Result. If no wrappedData
* is available, return -1.
*
* @throws javax.faces.FacesException if an error occurs getting the row count
*/
@Override
public int getRowCount() {
if (result == null) {
return (-1);
}
return (rows.length);
}
/**
* If row data is available, return the SortedMap array
* element at the index specified by rowIndex of the
* array returned by calling getRows() on the underlying
* Result. If no wrapped data is available,
* return null.
*
* Note that, if a non-null Map is returned
* by this method, it will contain the values of the columns for the
* current row, keyed by column name. Column name comparisons must be
* performed in a case-insensitive manner.
*
* @throws javax.faces.FacesException if an error occurs getting the row data
* @throws IllegalArgumentException if now row data is available
* at the currently specified row index
*/
@Override
public SortedMap getRowData() {
if (result == null) {
return (null);
} else if (!isRowAvailable()) {
throw new NoRowAvailableException();
} else {
//noinspection unchecked
return ((SortedMap)rows[index]);
}
}
/**
* @throws javax.faces.FacesException {@inheritDoc}
*/
@Override
public int getRowIndex() {
return (index);
}
/**
* @throws javax.faces.FacesException {@inheritDoc}
* @throws IllegalArgumentException {@inheritDoc}
*/
@Override
public void setRowIndex(int rowIndex) {
if (rowIndex < -1) {
throw new IllegalArgumentException();
}
int old = index;
index = rowIndex;
if (result == null) {
return;
}
DataModelListener [] listeners = getDataModelListeners();
if ((old != index) && (listeners != null)) {
SortedMap rowData = null;
if (isRowAvailable()) {
rowData = getRowData();
}
DataModelEvent event =
new DataModelEvent(this, index, rowData);
int n = listeners.length;
for (int i = 0; i < n; i++) {
if (null != listeners[i]) {
listeners[i].rowSelected(event);
}
}
}
}
@Override
public Object getWrappedData() {
return (this.result);
}
/**
* @throws ClassCastException if data is
* non-null and is not a Result
*/
@Override
public void setWrappedData(Object data) {
if (data == null) {
result = null;
rows = null;
setRowIndex(-1);
} else {
result = (Result) data;
rows = result.getRows();
index = -1;
setRowIndex(0);
}
}
}