History

My first initial commit with all of mine experimental changes.

Dmitry Kabak (userdima committed 13 years ago

Commit d37b88d1 parent 3f5b46618352 files · +2598093 −-8690Browse files

Showing the changes to java/pkg/com/sun/beans/decoder/NewElementHandler.java (1 of 18352 files). Show all

Unified · Split

java/pkg/com/sun/beans/decoder/NewElementHandler.java+205−0
@@ -0,0 +1,205 @@
1+/*
2+ * Copyright (c) 2008, Oracle and/or its affiliates. All rights reserved.
3+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4+ *
5+ * This code is free software; you can redistribute it and/or modify it
6+ * under the terms of the GNU General Public License version 2 only, as
7+ * published by the Free Software Foundation. Oracle designates this
8+ * particular file as subject to the "Classpath" exception as provided
9+ * by Oracle in the LICENSE file that accompanied this code.
10+ *
11+ * This code is distributed in the hope that it will be useful, but WITHOUT
12+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14+ * version 2 for more details (a copy is included in the LICENSE file that
15+ * accompanied this code).
16+ *
17+ * You should have received a copy of the GNU General Public License version
18+ * 2 along with this work; if not, write to the Free Software Foundation,
19+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20+ *
21+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22+ * or visit www.oracle.com if you need additional information or have any
23+ * questions.
24+ */
25+package com.sun.beans.decoder;
26+
27+import com.sun.beans.finder.ConstructorFinder;
28+
29+import java.lang.reflect.Array;
30+import java.lang.reflect.Constructor;
31+
32+import java.util.ArrayList;
33+import java.util.List;
34+
35+/**
36+ * This class is intended to handle <new> element.
37+ * It describes instantiation of the object.
38+ * The {@code class} attribute denotes
39+ * the name of the class to instantiate.
40+ * The inner elements specifies the arguments of the constructor.
41+ * For example:<pre>
42+ * &lt;new class="java.lang.Long"&gt;
43+ * &lt;string&gt;10&lt;/string&gt;
44+ * &lt;/new&gt;</pre>
45+ * is equivalent to {@code new Long("10")} in Java code.
46+ * <p>The following atributes are supported:
47+ * <dl>
48+ * <dt>class
49+ * <dd>the type of object for instantiation
50+ * <dt>id
51+ * <dd>the identifier of the variable that is intended to store the result
52+ * </dl>
53+ *
54+ * @since 1.7
55+ *
56+ * @author Sergey A. Malenkov
57+ */
58+class NewElementHandler extends ElementHandler {
59+ private List<Object> arguments = new ArrayList<Object>();
60+ private ValueObject value = ValueObjectImpl.VOID;
61+
62+ private Class<?> type;
63+
64+ /**
65+ * Parses attributes of the element.
66+ * The following atributes are supported:
67+ * <dl>
68+ * <dt>class
69+ * <dd>the type of object for instantiation
70+ * <dt>id
71+ * <dd>the identifier of the variable that is intended to store the result
72+ * </dl>
73+ *
74+ * @param name the attribute name
75+ * @param value the attribute value
76+ */
77+ @Override
78+ public void addAttribute(String name, String value) {
79+ if (name.equals("class")) { // NON-NLS: the attribute name
80+ this.type = getOwner().findClass(value);
81+ } else {
82+ super.addAttribute(name, value);
83+ }
84+ }
85+
86+ /**
87+ * Adds the argument to the list of arguments
88+ * that is used to calculate the value of this element.
89+ *
90+ * @param argument the value of the element that contained in this one
91+ */
92+ @Override
93+ protected final void addArgument(Object argument) {
94+ if (this.arguments == null) {
95+ throw new IllegalStateException("Could not add argument to evaluated element");
96+ }
97+ this.arguments.add(argument);
98+ }
99+
100+ /**
101+ * Returns the context of the method.
102+ * The context of the static method is the class object.
103+ * The context of the non-static method is the value of the parent element.
104+ *
105+ * @return the context of the method
106+ */
107+ @Override
108+ protected final Object getContextBean() {
109+ return (this.type != null)
110+ ? this.type
111+ : super.getContextBean();
112+ }
113+
114+ /**
115+ * Returns the value of this element.
116+ *
117+ * @return the value of this element
118+ */
119+ @Override
120+ protected final ValueObject getValueObject() {
121+ if (this.arguments != null) {
122+ try {
123+ this.value = getValueObject(this.type, this.arguments.toArray());
124+ }
125+ catch (Exception exception) {
126+ getOwner().handleException(exception);
127+ }
128+ finally {
129+ this.arguments = null;
130+ }
131+ }
132+ return this.value;
133+ }
134+
135+ /**
136+ * Calculates the value of this element
137+ * using the base class and the array of arguments.
138+ * By default, it creates an instance of the base class.
139+ * This method should be overridden in those handlers
140+ * that extend behavior of this element.
141+ *
142+ * @param type the base class
143+ * @param args the array of arguments
144+ * @return the value of this element
145+ * @throws Exception if calculation is failed
146+ */
147+ ValueObject getValueObject(Class<?> type, Object[] args) throws Exception {
148+ if (type == null) {
149+ throw new IllegalArgumentException("Class name is not set");
150+ }
151+ Class<?>[] types = getArgumentTypes(args);
152+ Constructor<?> constructor = ConstructorFinder.findConstructor(type, types);
153+ if (constructor.isVarArgs()) {
154+ args = getArguments(args, constructor.getParameterTypes());
155+ }
156+ return ValueObjectImpl.create(constructor.newInstance(args));
157+ }
158+
159+ /**
160+ * Converts the array of arguments to the array of corresponding classes.
161+ * If argument is {@code null} the class is {@code null} too.
162+ *
163+ * @param arguments the array of arguments
164+ * @return the array of corresponding classes
165+ */
166+ static Class<?>[] getArgumentTypes(Object[] arguments) {
167+ Class<?>[] types = new Class<?>[arguments.length];
168+ for (int i = 0; i < arguments.length; i++) {
169+ if (arguments[i] != null) {
170+ types[i] = arguments[i].getClass();
171+ }
172+ }
173+ return types;
174+ }
175+
176+ /**
177+ * Resolves variable arguments.
178+ *
179+ * @param arguments the array of arguments
180+ * @param types the array of parameter types
181+ * @return the resolved array of arguments
182+ */
183+ static Object[] getArguments(Object[] arguments, Class<?>[] types) {
184+ int index = types.length - 1;
185+ if (types.length == arguments.length) {
186+ Object argument = arguments[index];
187+ if (argument == null) {
188+ return arguments;
189+ }
190+ Class<?> type = types[index];
191+ if (type.isAssignableFrom(argument.getClass())) {
192+ return arguments;
193+ }
194+ }
195+ int length = arguments.length - index;
196+ Class<?> type = types[index].getComponentType();
197+ Object array = Array.newInstance(type, length);
198+ System.arraycopy(arguments, index, array, 0, length);
199+
200+ Object[] args = new Object[types.length];
201+ System.arraycopy(arguments, 0, args, 0, index);
202+ args[index] = array;
203+ return args;
204+ }
205+}