| /* |
| * Copyright (C) 2012 The Android Open Source Project |
| * |
| * 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 android.util; |
| |
| /** |
| * A value model for a {@link Property property} of a host object. This class can be used for |
| * both reflective and non-reflective property implementations. |
| * |
| * @param <H> the host type, where the host is the object that holds this property |
| * @param <T> the value type |
| * |
| * @see Property |
| * @see ValueModel |
| */ |
| public class PropertyValueModel<H, T> extends ValueModel<T> { |
| private final H mHost; |
| private final Property<H, T> mProperty; |
| |
| private PropertyValueModel(H host, Property<H, T> property) { |
| mProperty = property; |
| mHost = host; |
| } |
| |
| /** |
| * Returns the host. |
| * |
| * @return the host |
| */ |
| public H getHost() { |
| return mHost; |
| } |
| |
| /** |
| * Returns the property. |
| * |
| * @return the property |
| */ |
| public Property<H, T> getProperty() { |
| return mProperty; |
| } |
| |
| @Override |
| public Class<T> getType() { |
| return mProperty.getType(); |
| } |
| |
| @Override |
| public T get() { |
| return mProperty.get(mHost); |
| } |
| |
| @Override |
| public void set(T value) { |
| mProperty.set(mHost, value); |
| } |
| |
| /** |
| * Return an appropriate PropertyValueModel for this host and property. |
| * |
| * @param host the host |
| * @param property the property |
| * @return the value model |
| */ |
| public static <H, T> PropertyValueModel<H, T> of(H host, Property<H, T> property) { |
| return new PropertyValueModel<H, T>(host, property); |
| } |
| |
| /** |
| * Return a PropertyValueModel for this {@code host} and a |
| * reflective property, constructed from this {@code propertyType} and {@code propertyName}. |
| * |
| * @param host |
| * @param propertyType the property type |
| * @param propertyName the property name |
| * @return a value model with this host and a reflective property with this type and name |
| * |
| * @see Property#of |
| */ |
| public static <H, T> PropertyValueModel<H, T> of(H host, Class<T> propertyType, |
| String propertyName) { |
| return of(host, Property.of((Class<H>) host.getClass(), propertyType, propertyName)); |
| } |
| |
| private static Class getNullaryMethodReturnType(Class c, String name) { |
| try { |
| return c.getMethod(name).getReturnType(); |
| } catch (NoSuchMethodException e) { |
| return null; |
| } |
| } |
| |
| private static Class getFieldType(Class c, String name) { |
| try { |
| return c.getField(name).getType(); |
| } catch (NoSuchFieldException e) { |
| return null; |
| } |
| } |
| |
| private static String capitalize(String name) { |
| if (name.isEmpty()) { |
| return name; |
| } |
| return Character.toUpperCase(name.charAt(0)) + name.substring(1); |
| } |
| |
| /** |
| * Return a PropertyValueModel for this {@code host} and and {@code propertyName}. |
| * |
| * @param host the host |
| * @param propertyName the property name |
| * @return a value model with this host and a reflective property with this name |
| */ |
| public static PropertyValueModel of(Object host, String propertyName) { |
| Class clazz = host.getClass(); |
| String suffix = capitalize(propertyName); |
| Class propertyType = getNullaryMethodReturnType(clazz, "get" + suffix); |
| if (propertyType == null) { |
| propertyType = getNullaryMethodReturnType(clazz, "is" + suffix); |
| } |
| if (propertyType == null) { |
| propertyType = getFieldType(clazz, propertyName); |
| } |
| if (propertyType == null) { |
| throw new NoSuchPropertyException(propertyName); |
| } |
| return of(host, propertyType, propertyName); |
| } |
| } |