javax.faces.model.ResultSetDataModel Maven / Gradle / Ivy
/*
* $Id: ResultSetDataModel.java,v 1.33 2006/08/25 09:50:18 tony_robertson Exp $
*/
/*
* The contents of this file are subject to the terms
* of the Common Development and Distribution License
* (the License). You may not use this file except in
* compliance with the License.
*
* You can obtain a copy of the License at
* https://javaserverfaces.dev.java.net/CDDL.html or
* legal/CDDLv1.0.txt.
* See the License for the specific language governing
* permission and limitations under the License.
*
* When distributing Covered Code, include this CDDL
* Header Notice in each file and include the License file
* at legal/CDDLv1.0.txt.
* If applicable, add the following below the CDDL Header,
* with the fields enclosed by brackets [] replaced by
* your own identifying information:
* "Portions Copyrighted [year] [name of copyright owner]"
*
* [Name of File] [ver.__] [Date]
*
* Copyright 2005 Sun Microsystems Inc. All Rights Reserved
*/
package javax.faces.model;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.SQLException;
import java.util.AbstractCollection;
import java.util.AbstractSet;
import java.util.Collection;
import java.util.Comparator;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;
import java.util.TreeMap;
import javax.faces.FacesException;
/**
* ResultSetDataModel is a convenience implementation of
* {@link DataModel} that wraps a ResultSet
of Java objects.
* Note that the specified ResultSet
MUST
* be scrollable. In addition, if input components (that will be updating
* model values) reference this object in value binding expressions, the
* specified ResultSet
MUST be updatable.
*/
public class ResultSetDataModel extends DataModel {
// ------------------------------------------------------------ Constructors
/**
* Construct a new {@link ResultSetDataModel} with no specified
* wrapped data.
*/
public ResultSetDataModel() {
this(null);
}
/**
* Construct a new {@link ResultSetDataModel} wrapping the specified
* ResultSet
.
*
* @param resultSet ResultSet
to be wrapped (if any)
*/
public ResultSetDataModel(ResultSet resultSet) {
super();
setWrappedData(resultSet);
}
// ------------------------------------------------------ Instance Variables
// The current row index (zero relative)
private int index = -1;
// The metadata for the ResultSet we are wrapping (lazily instantiated)
private ResultSetMetaData metadata = null;
// The ResultSet we are wrapping
private ResultSet resultSet = null;
// Has the row at the current index been updated?
private boolean updated = false;
// -------------------------------------------------------------- Properties
/**
* Return true
if there is wrappedData
* available, and the result of calling absolute()
on the
* underlying ResultSet
, passing the current value of
* rowIndex
plus one (to account for the fact that
* ResultSet
uses one-relative indexing), returns
* true
. Otherwise, return false
.
*
* @throws FacesException if an error occurs getting the row availability
*/
public boolean isRowAvailable() {
if (resultSet == null) {
return (false);
} else if (index < 0) {
return (false);
}
try {
if (resultSet.absolute(index + 1)) {
return (true);
} else {
return (false);
}
} catch (SQLException e) {
throw new FacesException(e);
}
}
/**
* Return -1, since ResultSet
does not provide a
* standard way to determine the number of available rows without
* scrolling through the entire ResultSet
, and this can
* be very expensive if the number of rows is large.
*
* @throws FacesException if an error occurs getting the row count
*/
public int getRowCount() {
return (-1);
}
/**
* If row data is available, return a Map
representing
* the values of the columns for the row specified by rowIndex
,
* keyed by the corresponding column names. If no wrapped data is
* available, return null
.
*
* If a non-null
Map
is returned, its behavior
* must correspond to the contract for a mutable Map
as
* described in the JavaDocs for AbstractMap
, with the
* following exceptions and specialized behavior:
*
* - The
Map
, and any supporting objects it returns,
* must perform all column name comparisons in a
* case-insensitive manner. This case-insensitivity must be
* implemented using a case-insensitive Comparator
,
* such as
* String.CASE_INSENSITIVE_ORDER
.
* - The following methods must throw
*
UnsupportedOperationException
: clear()
,
* remove()
.
* - The
entrySet()
method must return a Set
* that has the following behavior:
*
* - Throw
UnsupportedOperationException
for any attempt
* to add or remove entries from the Set
, either
* directly or indirectly through an Iterator
* returned by the Set
.
* - Updates to the
value
of an entry in this
* set
must write through to the corresponding
* column value in the underlying ResultSet
.
*
* - The
keySet()
method must return a Set
* that throws UnsupportedOperationException
on any
* attempt to add or remove keys, either directly or through an
* Iterator
returned by the Set
.
* - The
put()
method must throw
* IllegalArgumentException
if a key value for which
* containsKey()
returns false
is
* specified. However, if a key already present in the Map
* is specified, the specified value must write through to the
* corresponding column value in the underlying ResultSet
.
*
* - The
values()
method must return a
* Collection
that throws
* UnsupportedOperationException
on any attempt to add
* or remove values, either directly or through an Iterator
* returned by the Collection
.
*
*
* @throws FacesException if an error occurs getting the row data
* @throws IllegalArgumentException if now row data is available
* at the currently specified row index
*/
public Object getRowData() {
if (resultSet == null) {
return (null);
} else if (!isRowAvailable()) {
throw new IllegalArgumentException();
}
try {
getMetaData();
return (new ResultSetMap(String.CASE_INSENSITIVE_ORDER));
} catch (SQLException e) {
throw new FacesException(e);
}
}
/**
* @throws FacesException {@inheritDoc}
*/
public int getRowIndex() {
return (index);
}
/**
* @throws FacesException {@inheritDoc}
* @throws IllegalArgumentException {@inheritDoc}
*/
public void setRowIndex(int rowIndex) {
if (rowIndex < -1) {
throw new IllegalArgumentException();
}
// Tell the ResultSet that the previous row was updated if necessary
if (updated && (resultSet != null)) {
try {
if (!resultSet.rowDeleted()) {
resultSet.updateRow();
}
updated = false;
} catch (SQLException e) {
throw new FacesException(e);
}
}
int old = index;
index = rowIndex;
if (resultSet == null) {
return;
}
DataModelListener [] listeners = getDataModelListeners();
if ((old != index) && (listeners != null)) {
Object 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);
}
}
}
}
public Object getWrappedData() {
return (this.resultSet);
}
/**
* @throws ClassCastException {@inheritDoc}
*/
public void setWrappedData(Object data) {
if (data == null) {
metadata = null;
resultSet = null;
setRowIndex(-1);
} else {
metadata = null;
resultSet = (ResultSet) data;
index = -1;
setRowIndex(0);
}
}
// --------------------------------------------------------- Private Methods
/**
* Return the ResultSetMetaData
for the
* ResultSet
we are wrapping, caching it the first time
* it is returned.
*
* @throws FacesException if the ResultSetMetaData
* cannot be acquired
*/
private ResultSetMetaData getMetaData() {
if (metadata == null) {
try {
metadata = resultSet.getMetaData();
} catch (SQLException e) {
throw new FacesException(e);
}
}
return (metadata);
}
/**
* Mark the current row as having been updated, so that we will call
* updateRow()
before moving elsewhere.
*/
private void updated() {
this.updated = true;
}
// --------------------------------------------------------- Private Classes
// Private implementation of Map that delegates column get and put
// operations to the underlying ResultSet, after setting the required
// row index
private class ResultSetMap extends TreeMap {
public ResultSetMap(Comparator comparator) throws SQLException {
super(comparator);
index = ResultSetDataModel.this.index;
resultSet.absolute(index + 1);
int n = metadata.getColumnCount();
for (int i = 1; i <= n; i++) {
super.put(metadata.getColumnName(i),
metadata.getColumnName(i));
}
}
// The zero-relative row index of our row
private int index;
// Removing entries is not allowed
public void clear() {
throw new UnsupportedOperationException();
}
public boolean containsValue(Object value) {
for (Iterator i = entrySet().iterator(); i .hasNext(); ) {
Map.Entry entry = (Map.Entry) i.next();
Object contained = entry.getValue();
if (value == null) {
if (contained == null) {
return (true);
}
} else {
if (value.equals(contained)) {
return (true);
}
}
}
return (false);
}
public Set> entrySet() {
return (new ResultSetEntries(this));
}
public Object get(Object key) {
if (!containsKey(key)) {
return (null);
}
try {
resultSet.absolute(index + 1);
return (resultSet.getObject((String) realKey(key)));
} catch (SQLException e) {
throw new FacesException(e);
}
}
public Set keySet() {
return (new ResultSetKeys(this));
}
public Object put(String key, Object value) {
if (!containsKey(key)) {
throw new IllegalArgumentException();
}
if (!(key instanceof String)) {
throw new IllegalArgumentException();
}
try {
resultSet.absolute(index + 1);
Object previous = resultSet.getObject((String) realKey(key));
if ((previous == null) && (value == null)) {
return (previous);
} else if ((previous != null) && (value != null) &&
previous.equals(value)) {
return (previous);
}
resultSet.updateObject((String) realKey(key), value);
ResultSetDataModel.this.updated();
return (previous);
} catch (SQLException e) {
throw new FacesException(e);
}
}
public void putAll(Map extends String, ? extends Object> map) {
for (Map.Entry extends String, ? extends Object> entry : map.entrySet()) {
put(entry.getKey(), entry.getValue());
}
}
// Removing entries is not allowed
public Object remove(Object key) {
throw new UnsupportedOperationException();
}
public Collection