/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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 freemarker.ext.beans;
import java.util.
List;
import java.util.
Map;
import java.util.
Set;
import freemarker.ext.util.
ModelFactory;
import freemarker.template.
ObjectWrapper;
import freemarker.template.
TemplateMethodModelEx;
import freemarker.template.
TemplateModel;
import freemarker.template.
TemplateModelException;
/**
* <p>A special case of {@link BeanModel} that adds implementation
* for {@link TemplateMethodModelEx} on map objects that is a shortcut for the
* <tt>Map.get()</tt> method. Note that if the passed argument itself is a
* reflection-wrapper model, then the map lookup will be performed using the
* wrapped object as the key. Note that you can call <tt>get()</tt> using the
* <tt>map.key</tt> syntax inherited from {@link BeanModel} as well,
* however in that case the key is always a string.</p>
* <p>The class itself does not implement the {@link freemarker.template.TemplateCollectionModel}.
* You can, however use <tt>map.entrySet()</tt>, <tt>map.keySet()</tt>, or
* <tt>map.values()</tt> to obtain {@link freemarker.template.TemplateCollectionModel} instances for
* various aspects of the map.</p>
*/
public class
MapModel
extends
StringModel
implements
TemplateMethodModelEx {
static final
ModelFactory FACTORY =
new
ModelFactory()
{
public
TemplateModel create(
Object object,
ObjectWrapper wrapper) {
return new
MapModel((
Map)
object, (
BeansWrapper)
wrapper);
}
};
/**
* Creates a new model that wraps the specified map object.
* @param map the map object to wrap into a model.
* @param wrapper the {@link BeansWrapper} associated with this model.
* Every model has to have an associated {@link BeansWrapper} instance. The
* model gains many attributes from its wrapper, including the caching
* behavior, method exposure level, method-over-item shadowing policy etc.
*/
public
MapModel(
Map map,
BeansWrapper wrapper) {
super(
map,
wrapper);
}
/**
* The first argument is used as a key to call the map's <tt>get</tt> method.
*/
public
Object exec(
List arguments)
throws
TemplateModelException {
Object key =
unwrap((
TemplateModel)
arguments.
get(0));
return
wrap(((
Map)
object).
get(
key));
}
/**
* Overridden to invoke the generic get method by casting to Map instead of
* through reflection - should yield better performance.
*/
@
Override
protected
TemplateModel invokeGenericGet(
Map keyMap,
Class clazz,
String key)
throws
TemplateModelException {
Map map = (
Map)
object;
Object val =
map.
get(
key);
if (
val == null) {
if (
key.
length() == 1) {
// just check for Character key if this is a single-character string
Character charKey =
Character.
valueOf(
key.
charAt(0));
val =
map.
get(
charKey);
if (
val == null && !(
map.
containsKey(
key) ||
map.
containsKey(
charKey))) {
return
UNKNOWN;
}
} else if (!
map.
containsKey(
key)) {
return
UNKNOWN;
}
}
return
wrap(
val);
}
@
Override
public boolean
isEmpty() {
return ((
Map)
object).
isEmpty() && super.isEmpty();
}
@
Override
public int
size() {
return
keySet().
size();
}
@
Override
protected
Set keySet() {
Set set = super.keySet();
set.
addAll(((
Map)
object).
keySet());
return
set;
}
}