001/*
002 * Copyright 2002-2018 the original author or authors.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 *      https://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016
017package org.springframework.expression.spel.support;
018
019import java.lang.reflect.Method;
020
021/**
022 * A {@link org.springframework.expression.PropertyAccessor} variant for data binding
023 * purposes, using reflection to access properties for reading and possibly writing.
024 *
025 * <p>A property can be referenced through a public getter method (when being read)
026 * or a public setter method (when being written), and also as a public field.
027 *
028 * <p>This accessor is explicitly designed for user-declared properties and does not
029 * resolve technical properties on {@code java.lang.Object} or {@code java.lang.Class}.
030 * For unrestricted resolution, choose {@link ReflectivePropertyAccessor} instead.
031 *
032 * @author Juergen Hoeller
033 * @since 4.3.15
034 * @see #forReadOnlyAccess()
035 * @see #forReadWriteAccess()
036 * @see SimpleEvaluationContext
037 * @see StandardEvaluationContext
038 * @see ReflectivePropertyAccessor
039 */
040public class DataBindingPropertyAccessor extends ReflectivePropertyAccessor {
041
042        /**
043         * Create a new property accessor for reading and possibly also writing.
044         * @param allowWrite whether to also allow for write operations
045         * @see #canWrite
046         */
047        private DataBindingPropertyAccessor(boolean allowWrite) {
048                super(allowWrite);
049        }
050
051        @Override
052        protected boolean isCandidateForProperty(Method method, Class<?> targetClass) {
053                Class<?> clazz = method.getDeclaringClass();
054                return (clazz != Object.class && clazz != Class.class && !ClassLoader.class.isAssignableFrom(targetClass));
055        }
056
057
058        /**
059         * Create a new data-binding property accessor for read-only operations.
060         */
061        public static DataBindingPropertyAccessor forReadOnlyAccess() {
062                return new DataBindingPropertyAccessor(false);
063        }
064
065        /**
066         * Create a new data-binding property accessor for read-write operations.
067         */
068        public static DataBindingPropertyAccessor forReadWriteAccess() {
069                return new DataBindingPropertyAccessor(true);
070        }
071
072}