// Copyright 2006, 2007 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.internal.services;
import org.apache.tapestry.annotations.Environmental;
import org.apache.tapestry.model.MutableComponentModel;
import org.apache.tapestry.services.ClassTransformation;
import org.apache.tapestry.services.ComponentClassTransformWorker;
import org.apache.tapestry.services.Environment;
import org.apache.tapestry.services.TransformMethodSignature;
import java.lang.reflect.Modifier;
import java.util.List;
/**
* Obtains a value from the {@link Environment} service based on the field type. This is triggered
* by the presence of the {@link Environmental} annotation.
*/
public class EnvironmentalWorker implements ComponentClassTransformWorker
{
private final Environment _environment;
public EnvironmentalWorker(Environment environment)
{
_environment = environment;
}
public void transform(ClassTransformation transformation, MutableComponentModel model)
{
List<String> names = transformation.findFieldsWithAnnotation(Environmental.class);
if (names.isEmpty())
return;
// TODO: addInjectField should be smart about if the field has already been injected (with
// the same type)
// for this transformation, or the parent transformation.
String envField = transformation.addInjectedField(
Environment.class,
"environment",
_environment);
for (String name : names)
{
Environmental annotation = transformation.getFieldAnnotation(name, Environmental.class);
String type = transformation.getFieldType(name);
// TODO: Check for primitives
// Caching might be good for efficiency at some point.
String methodName = transformation.newMemberName("environment_read", name);
TransformMethodSignature sig = new TransformMethodSignature(Modifier.PRIVATE, type, methodName, null,
null);
String body = String.format(
"return ($r) %s.%s($type);",
envField,
annotation.value() ? "peekRequired" : "peek");
transformation.addMethod(sig, body);
transformation.replaceReadAccess(name, methodName);
transformation.makeReadOnly(name);
transformation.removeField(name);
transformation.claimField(name, annotation);
}
}
}