001 /* 002 * Created on Aug 17, 2006 003 * 004 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with 005 * the License. You may obtain a copy of the License at 006 * 007 * http://www.apache.org/licenses/LICENSE-2.0 008 * 009 * Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on 010 * an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the 011 * specific language governing permissions and limitations under the License. 012 * 013 * Copyright @2006-2009 the original author or authors. 014 */ 015 package org.fest.reflect.field; 016 017 import static org.fest.reflect.field.Invoker.newInvoker; 018 019 import org.fest.reflect.exception.ReflectionError; 020 021 /** 022 * Understands the type of a field to access using Java Reflection. 023 * <p> 024 * The following is an example of proper usage of this class: 025 * <pre> 026 * // Retrieves the value of the field "name" 027 * String name = {@link org.fest.reflect.core.Reflection#field(String) field}("name").{@link FieldName#ofType(Class) ofType}(String.class).{@link FieldType#in(Object) in}(person).{@link Invoker#get() get}(); 028 * 029 * // Sets the value of the field "name" to "Yoda" 030 * {@link org.fest.reflect.core.Reflection#field(String) field}("name").{@link FieldName#ofType(Class) ofType}(String.class).{@link FieldType#in(Object) in}(person).{@link Invoker#set(Object) set}("Yoda"); 031 * </pre> 032 * </p> 033 * 034 * @param <T> the generic type of the field. 035 * 036 * @author Alex Ruiz 037 */ 038 public class FieldType<T> { 039 040 static <T> FieldType<T> newFieldType(String name, Class<T> type) { 041 if (type == null) throw new NullPointerException("The type of the field to access should not be null"); 042 return new FieldType<T>(name, type); 043 } 044 045 private final String name; 046 private final Class<T> type; 047 048 private FieldType(String name, Class<T> type) { 049 this.name = name; 050 this.type = type; 051 } 052 053 /** 054 * Returns a new field access invoker, capable of accessing (read/write) the underlying field. 055 * @param target the object containing the field of interest. 056 * @return the created field access invoker. 057 * @throws NullPointerException if the given target is <code>null</code>. 058 * @throws ReflectionError if a field with a matching name and type cannot be found. 059 */ 060 public Invoker<T> in(Object target) { 061 return newInvoker(name, type, target); 062 } 063 }