| /* |
| * Copyright (c) 2008, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| package com.sun.beans.decoder; |
| |
| import com.sun.beans.finder.FieldFinder; |
| |
| import java.lang.reflect.Field; |
| |
| /** |
| * This class is intended to handle <field> element. |
| * This element simplifies access to the fields. |
| * If the {@code class} attribute is specified |
| * this element accesses static field of specified class. |
| * This element defines getter if it contains no argument. |
| * It returns the value of the field in this case. |
| * For example:<pre> |
| * <field name="TYPE" class="java.lang.Long"/></pre> |
| * is equivalent to {@code Long.TYPE} in Java code. |
| * This element defines setter if it contains one argument. |
| * It does not return the value of the field in this case. |
| * For example:<pre> |
| * <field name="id"><int>0</int></field></pre> |
| * is equivalent to {@code id = 0} in Java code. |
| * <p>The following atributes are supported: |
| * <dl> |
| * <dt>name |
| * <dd>the field name |
| * <dt>class |
| * <dd>the type is used for static fields only |
| * <dt>id |
| * <dd>the identifier of the variable that is intended to store the result |
| * </dl> |
| * |
| * @since 1.7 |
| * |
| * @author Sergey A. Malenkov |
| */ |
| final class FieldElementHandler extends AccessorElementHandler { |
| private Class<?> type; |
| |
| /** |
| * Parses attributes of the element. |
| * The following atributes are supported: |
| * <dl> |
| * <dt>name |
| * <dd>the field name |
| * <dt>class |
| * <dd>the type is used for static fields only |
| * <dt>id |
| * <dd>the identifier of the variable that is intended to store the result |
| * </dl> |
| * |
| * @param name the attribute name |
| * @param value the attribute value |
| */ |
| @Override |
| public void addAttribute(String name, String value) { |
| if (name.equals("class")) { // NON-NLS: the attribute name |
| this.type = getOwner().findClass(value); |
| } else { |
| super.addAttribute(name, value); |
| } |
| } |
| |
| /** |
| * Tests whether the value of this element can be used |
| * as an argument of the element that contained in this one. |
| * |
| * @return {@code true} if the value of this element should be used |
| * as an argument of the element that contained in this one, |
| * {@code false} otherwise |
| */ |
| @Override |
| protected boolean isArgument() { |
| return super.isArgument() && (this.type != null); // only static accessor can be used an argument |
| } |
| |
| /** |
| * Returns the context of the field. |
| * The context of the static field is the class object. |
| * The context of the non-static field is the value of the parent element. |
| * |
| * @return the context of the field |
| */ |
| @Override |
| protected Object getContextBean() { |
| return (this.type != null) |
| ? this.type |
| : super.getContextBean(); |
| } |
| |
| /** |
| * Returns the value of the field with specified {@code name}. |
| * |
| * @param name the name of the field |
| * @return the value of the specified field |
| */ |
| @Override |
| protected Object getValue(String name) { |
| try { |
| return getFieldValue(getContextBean(), name); |
| } |
| catch (Exception exception) { |
| getOwner().handleException(exception); |
| } |
| return null; |
| } |
| |
| /** |
| * Sets the new value for the field with specified {@code name}. |
| * |
| * @param name the name of the field |
| * @param value the new value for the specified field |
| */ |
| @Override |
| protected void setValue(String name, Object value) { |
| try { |
| setFieldValue(getContextBean(), name, value); |
| } |
| catch (Exception exception) { |
| getOwner().handleException(exception); |
| } |
| } |
| |
| /** |
| * Performs the search of the field with specified {@code name} |
| * in specified context and returns its value. |
| * |
| * @param bean the context bean that contains field |
| * @param name the name of the field |
| * @return the value of the field |
| * @throws IllegalAccessException if the field is not accesible |
| * @throws NoSuchFieldException if the field is not found |
| */ |
| static Object getFieldValue(Object bean, String name) throws IllegalAccessException, NoSuchFieldException { |
| return findField(bean, name).get(bean); |
| } |
| |
| /** |
| * Performs the search of the field with specified {@code name} |
| * in specified context and updates its value. |
| * |
| * @param bean the context bean that contains field |
| * @param name the name of the field |
| * @param value the new value for the field |
| * @throws IllegalAccessException if the field is not accesible |
| * @throws NoSuchFieldException if the field is not found |
| */ |
| private static void setFieldValue(Object bean, String name, Object value) throws IllegalAccessException, NoSuchFieldException { |
| findField(bean, name).set(bean, value); |
| } |
| |
| /** |
| * Performs the search of the field |
| * with specified {@code name} in specified context. |
| * |
| * @param bean the context bean that contains field |
| * @param name the name of the field |
| * @return field object that represents found field |
| * @throws NoSuchFieldException if the field is not found |
| */ |
| private static Field findField(Object bean, String name) throws NoSuchFieldException { |
| return (bean instanceof Class<?>) |
| ? FieldFinder.findStaticField((Class<?>) bean, name) |
| : FieldFinder.findField(bean.getClass(), name); |
| } |
| } |
