com.google.web.bindery.autobean.vm.impl.MethodPropertyContext Maven / Gradle / Ivy
/*
* Copyright 2010 Google Inc.
*
* 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 com.google.web.bindery.autobean.vm.impl;
import com.google.web.bindery.autobean.shared.AutoBeanVisitor.CollectionPropertyContext;
import com.google.web.bindery.autobean.shared.AutoBeanVisitor.MapPropertyContext;
import com.google.web.bindery.autobean.shared.AutoBeanVisitor.ParameterizationVisitor;
import java.lang.reflect.Method;
import java.lang.reflect.Type;
import java.util.Collection;
import java.util.Map;
import java.util.WeakHashMap;
/**
* A base type to handle analyzing the return value of a getter method. The
* accessor methods are implemented in subtypes.
*/
abstract class MethodPropertyContext implements CollectionPropertyContext,
MapPropertyContext {
private static class Data {
Class elementType;
Type genericType;
Class keyType;
Class valueType;
Class type;
}
/**
* Save prior instances in order to decrease the amount of data computed.
*/
private static final Map cache = new WeakHashMap();
private final Data data;
public MethodPropertyContext(Method getter) {
synchronized (cache) {
Data previous = cache.get(getter);
if (previous != null) {
this.data = previous;
return;
}
this.data = new Data();
data.genericType = getter.getGenericReturnType();
data.type = getter.getReturnType();
// Compute collection element type
if (Collection.class.isAssignableFrom(getType())) {
data.elementType = TypeUtils.ensureBaseType(TypeUtils.getSingleParameterization(
Collection.class, getter.getGenericReturnType(),
getter.getReturnType()));
} else if (Map.class.isAssignableFrom(getType())) {
Type[] types = TypeUtils.getParameterization(Map.class,
getter.getGenericReturnType());
data.keyType = TypeUtils.ensureBaseType(types[0]);
data.valueType = TypeUtils.ensureBaseType(types[1]);
}
cache.put(getter, data);
}
}
public void accept(ParameterizationVisitor visitor) {
traverse(visitor, data.genericType);
}
public abstract boolean canSet();
public Class getElementType() {
return data.elementType;
}
public Class getKeyType() {
return data.keyType;
}
public Class getType() {
return data.type;
}
public Class getValueType() {
return data.valueType;
}
public abstract void set(Object value);
private void traverse(ParameterizationVisitor visitor, Type type) {
Class base = TypeUtils.ensureBaseType(type);
if (visitor.visitType(base)) {
Type[] params = TypeUtils.getParameterization(base, type);
for (Type t : params) {
if (visitor.visitParameter()) {
traverse(visitor, t);
}
visitor.endVisitParameter();
}
}
visitor.endVisitType(base);
}
}