| /* |
| * Copyright (c) 2008, 2013, 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.ConstructorFinder; |
| |
| import java.lang.reflect.Array; |
| import java.lang.reflect.Constructor; |
| |
| import java.util.ArrayList; |
| import java.util.List; |
| |
| /** |
| * This class is intended to handle <new> element. |
| * It describes instantiation of the object. |
| * The {@code class} attribute denotes |
| * the name of the class to instantiate. |
| * The inner elements specifies the arguments of the constructor. |
| * For example:<pre> |
| * <new class="java.lang.Long"> |
| * <string>10</string> |
| * </new></pre> |
| * is equivalent to {@code Long.valueOf("10")} in Java code. |
| * <p>The following attributes are supported: |
| * <dl> |
| * <dt>class |
| * <dd>the type of object for instantiation |
| * <dt>id |
| * <dd>the identifier of the variable that is intended to store the result |
| * </dl> |
| * |
| * @since 1.7 |
| * |
| * @author Sergey A. Malenkov |
| */ |
| class NewElementHandler extends ElementHandler { |
| private List<Object> arguments = new ArrayList<Object>(); |
| private ValueObject value = ValueObjectImpl.VOID; |
| |
| private Class<?> type; |
| |
| /** |
| * Parses attributes of the element. |
| * The following attributes are supported: |
| * <dl> |
| * <dt>class |
| * <dd>the type of object for instantiation |
| * <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); |
| } |
| } |
| |
| /** |
| * Adds the argument to the list of arguments |
| * that is used to calculate the value of this element. |
| * |
| * @param argument the value of the element that contained in this one |
| */ |
| @Override |
| protected final void addArgument(Object argument) { |
| if (this.arguments == null) { |
| throw new IllegalStateException("Could not add argument to evaluated element"); |
| } |
| this.arguments.add(argument); |
| } |
| |
| /** |
| * Returns the context of the method. |
| * The context of the static method is the class object. |
| * The context of the non-static method is the value of the parent element. |
| * |
| * @return the context of the method |
| */ |
| @Override |
| protected final Object getContextBean() { |
| return (this.type != null) |
| ? this.type |
| : super.getContextBean(); |
| } |
| |
| /** |
| * Returns the value of this element. |
| * |
| * @return the value of this element |
| */ |
| @Override |
| protected final ValueObject getValueObject() { |
| if (this.arguments != null) { |
| try { |
| this.value = getValueObject(this.type, this.arguments.toArray()); |
| } |
| catch (Exception exception) { |
| getOwner().handleException(exception); |
| } |
| finally { |
| this.arguments = null; |
| } |
| } |
| return this.value; |
| } |
| |
| /** |
| * Calculates the value of this element |
| * using the base class and the array of arguments. |
| * By default, it creates an instance of the base class. |
| * This method should be overridden in those handlers |
| * that extend behavior of this element. |
| * |
| * @param type the base class |
| * @param args the array of arguments |
| * @return the value of this element |
| * @throws Exception if calculation is failed |
| */ |
| ValueObject getValueObject(Class<?> type, Object[] args) throws Exception { |
| if (type == null) { |
| throw new IllegalArgumentException("Class name is not set"); |
| } |
| Class<?>[] types = getArgumentTypes(args); |
| Constructor<?> constructor = ConstructorFinder.findConstructor(type, types); |
| if (constructor.isVarArgs()) { |
| args = getArguments(args, constructor.getParameterTypes()); |
| } |
| return ValueObjectImpl.create(constructor.newInstance(args)); |
| } |
| |
| /** |
| * Converts the array of arguments to the array of corresponding classes. |
| * If argument is {@code null} the class is {@code null} too. |
| * |
| * @param arguments the array of arguments |
| * @return the array of corresponding classes |
| */ |
| static Class<?>[] getArgumentTypes(Object[] arguments) { |
| Class<?>[] types = new Class<?>[arguments.length]; |
| for (int i = 0; i < arguments.length; i++) { |
| if (arguments[i] != null) { |
| types[i] = arguments[i].getClass(); |
| } |
| } |
| return types; |
| } |
| |
| /** |
| * Resolves variable arguments. |
| * |
| * @param arguments the array of arguments |
| * @param types the array of parameter types |
| * @return the resolved array of arguments |
| */ |
| static Object[] getArguments(Object[] arguments, Class<?>[] types) { |
| int index = types.length - 1; |
| if (types.length == arguments.length) { |
| Object argument = arguments[index]; |
| if (argument == null) { |
| return arguments; |
| } |
| Class<?> type = types[index]; |
| if (type.isAssignableFrom(argument.getClass())) { |
| return arguments; |
| } |
| } |
| int length = arguments.length - index; |
| Class<?> type = types[index].getComponentType(); |
| Object array = Array.newInstance(type, length); |
| System.arraycopy(arguments, index, array, 0, length); |
| |
| Object[] args = new Object[types.length]; |
| System.arraycopy(arguments, 0, args, 0, index); |
| args[index] = array; |
| return args; |
| } |
| } |