javaa.beans.ClassPersistenceDelegate Maven / Gradle / Ivy
/*
* 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 javaa.beans;
import javaa.beans.Encoder;
import javaa.beans.Expression;
import javaa.beans.PersistenceDelegate;
import java.lang.reflect.Field;
class ClassPersistenceDelegate extends PersistenceDelegate {
@Override
protected Expression instantiate(Object oldInstance, Encoder out) {
Class value = (Class) oldInstance;
Field fld = null;
final String TYPE = "TYPE"; //$NON-NLS-1$
Expression result;
/*
* Special treatment to String.class to prevent endless loop of
* instantiation.
*/
if (value == String.class) {
return new Expression(value, "", "getClass", null); //$NON-NLS-1$//$NON-NLS-2$
}
try {
if (value.equals(Integer.TYPE)) {
fld = Integer.class.getField(TYPE);
} else if (value.equals(Short.TYPE)) {
fld = Short.class.getField(TYPE);
} else if (value.equals(Long.TYPE)) {
fld = Long.class.getField(TYPE);
} else if (value.equals(Float.TYPE)) {
fld = Float.class.getField(TYPE);
} else if (value.equals(Double.TYPE)) {
fld = Double.class.getField(TYPE);
} else if (value.equals(Byte.TYPE)) {
fld = Byte.class.getField(TYPE);
} else if (value.equals(Character.TYPE)) {
fld = Character.class.getField(TYPE);
} else if (value.equals(Boolean.TYPE)) {
fld = Boolean.class.getField(TYPE);
}
} catch (NoSuchFieldException e) {
// impossible situation for valid java.lang classes
// implementation with version >= 1.1
throw new AssertionError(e);
}
if (fld != null) {
// we have primitive type
result = new Expression(oldInstance, fld,
"get", new Object[] { null }); //$NON-NLS-1$
} else {
result = new Expression(oldInstance, String.class, "forName", //$NON-NLS-1$
new Object[] { value.getName() });
}
return result;
}
@Override
/*
* It's unnecessary to do anything for initialization, because two mutatable
* class objects are actually the same.
*/
protected void initialize(Class type, Object oldInstance,
Object newInstance, Encoder out) {
// do nothing
}
@Override
protected boolean mutatesTo(Object oldInstance, Object newInstance) {
if (oldInstance instanceof Class && newInstance instanceof Class) {
Class c1 = (Class) oldInstance;
Class c2 = (Class) newInstance;
if (c1.getName().equals(c2.getName())) {
return true;
}
return false;
}
return super.mutatesTo(oldInstance, newInstance);
}
}