You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
385 lines
16 KiB
385 lines
16 KiB
/* |
|
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER. |
|
* |
|
* Copyright (c) 1997-2010 Oracle and/or its affiliates. All rights reserved. |
|
* |
|
* The contents of this file are subject to the terms of either the GNU |
|
* General Public License Version 2 only ("GPL") or the Common Development |
|
* and Distribution License("CDDL") (collectively, the "License"). You |
|
* may not use this file except in compliance with the License. You can |
|
* obtain a copy of the License at |
|
* https://glassfish.dev.java.net/public/CDDL+GPL_1_1.html |
|
* or packager/legal/LICENSE.txt. See the License for the specific |
|
* language governing permissions and limitations under the License. |
|
* |
|
* When distributing the software, include this License Header Notice in each |
|
* file and include the License file at packager/legal/LICENSE.txt. |
|
* |
|
* GPL Classpath Exception: |
|
* Oracle designates this particular file as subject to the "Classpath" |
|
* exception as provided by Oracle in the GPL Version 2 section of the License |
|
* file that accompanied this code. |
|
* |
|
* Modifications: |
|
* If applicable, add the following below the License Header, with the fields |
|
* enclosed by brackets [] replaced by your own identifying information: |
|
* "Portions Copyright [year] [name of copyright owner]" |
|
* |
|
* Contributor(s): |
|
* If you wish your version of this file to be governed by only the CDDL or |
|
* only the GPL Version 2, indicate your decision by adding "[Contributor] |
|
* elects to include this software in this distribution under the [CDDL or GPL |
|
* Version 2] license." If you don't indicate a single choice of license, a |
|
* recipient has the option to distribute your version of this file under |
|
* either the CDDL, the GPL Version 2 or to extend the choice of license to |
|
* its licensees as provided above. However, if you add GPL Version 2 code |
|
* and therefore, elected the GPL Version 2 license, then the option applies |
|
* only if the new code is made subject to such option by the copyright |
|
* holder. |
|
* |
|
* |
|
* This file incorporates work covered by the following copyright and |
|
* permission notice: |
|
* |
|
* Copyright 2004 The Apache Software Foundation |
|
* |
|
* Licensed under the Apache License, Version 2.0 (the "License"); |
|
* you may not use this file except in compliance with the License. |
|
* You may obtain a copy of the License at |
|
* |
|
* http://www.apache.org/licenses/LICENSE-2.0 |
|
* |
|
* Unless required by applicable law or agreed to in writing, software |
|
* distributed under the License is distributed on an "AS IS" BASIS, |
|
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
|
* See the License for the specific language governing permissions and |
|
* limitations under the License. |
|
*/ |
|
|
|
package javax.el; |
|
|
|
import java.lang.reflect.Array; |
|
import java.util.List; |
|
import java.util.Iterator; |
|
import java.beans.FeatureDescriptor; |
|
|
|
/** |
|
* Defines property resolution behavior on arrays. |
|
* |
|
* <p>This resolver handles base objects that are Java language arrays. |
|
* It accepts any object as a property and coerces that object into an |
|
* integer index into the array. The resulting value is the value in the array |
|
* at that index.</p> |
|
* |
|
* <p>This resolver can be constructed in read-only mode, which means that |
|
* {@link #isReadOnly} will always return <code>true</code> and |
|
* {@link #setValue} will always throw |
|
* <code>PropertyNotWritableException</code>.</p> |
|
* |
|
* <p><code>ELResolver</code>s are combined together using |
|
* {@link CompositeELResolver}s, to define rich semantics for evaluating |
|
* an expression. See the javadocs for {@link ELResolver} for details.</p> |
|
* |
|
* @see CompositeELResolver |
|
* @see ELResolver |
|
* @since JSP 2.1 |
|
*/ |
|
public class ArrayELResolver extends ELResolver { |
|
|
|
/** |
|
* Creates a new read/write <code>ArrayELResolver</code>. |
|
*/ |
|
public ArrayELResolver() { |
|
this.isReadOnly = false; |
|
} |
|
|
|
/** |
|
* Creates a new <code>ArrayELResolver</code> whose read-only status is |
|
* determined by the given parameter. |
|
* |
|
* @param isReadOnly <code>true</code> if this resolver cannot modify |
|
* arrays; <code>false</code> otherwise. |
|
*/ |
|
public ArrayELResolver(boolean isReadOnly) { |
|
this.isReadOnly = isReadOnly; |
|
} |
|
|
|
/** |
|
* If the base object is an array, returns the most general acceptable type |
|
* for a value in this array. |
|
* |
|
* <p>If the base is a <code>array</code>, the |
|
* <code>propertyResolved</code> property of the <code>ELContext</code> |
|
* object must be set to <code>true</code> by this resolver, before |
|
* returning. If this property is not <code>true</code> after this method |
|
* is called, the caller should ignore the return value.</p> |
|
* |
|
* <p>Assuming the base is an <code>array</code>, this method will always |
|
* return <code>base.getClass().getComponentType()</code>, which is |
|
* the most general type of component that can be stored at any given |
|
* index in the array.</p> |
|
* |
|
* @param context The context of this evaluation. |
|
* @param base The array to analyze. Only bases that are Java language |
|
* arrays are handled by this resolver. |
|
* @param property The index of the element in the array to return the |
|
* acceptable type for. Will be coerced into an integer, but |
|
* otherwise ignored by this resolver. |
|
* @return If the <code>propertyResolved</code> property of |
|
* <code>ELContext</code> was set to <code>true</code>, then |
|
* the most general acceptable type; otherwise undefined. |
|
* @throws PropertyNotFoundException if the given index is out of |
|
* bounds for this array. |
|
* @throws NullPointerException if context is <code>null</code> |
|
* @throws ELException if an exception was thrown while performing |
|
* the property or variable resolution. The thrown exception |
|
* must be included as the cause property of this exception, if |
|
* available. |
|
*/ |
|
public Class<?> getType(ELContext context, |
|
Object base, |
|
Object property) { |
|
|
|
if (context == null) { |
|
throw new NullPointerException(); |
|
} |
|
|
|
if (base != null && base.getClass().isArray()) { |
|
context.setPropertyResolved(true); |
|
int index = toInteger (property); |
|
if (index < 0 || index >= Array.getLength(base)) { |
|
throw new PropertyNotFoundException(); |
|
} |
|
return base.getClass().getComponentType(); |
|
} |
|
return null; |
|
} |
|
|
|
/** |
|
* If the base object is a Java language array, returns the value at the |
|
* given index. The index is specified by the <code>property</code> |
|
* argument, and coerced into an integer. If the coercion could not be |
|
* performed, an <code>IllegalArgumentException</code> is thrown. If the |
|
* index is out of bounds, <code>null</code> is returned. |
|
* |
|
* <p>If the base is a Java language array, the |
|
* <code>propertyResolved</code> property of the <code>ELContext</code> |
|
* object must be set to <code>true</code> by this resolver, before |
|
* returning. If this property is not <code>true</code> after this |
|
* method is called, the caller should ignore the return value.</p> |
|
* |
|
* @param context The context of this evaluation. |
|
* @param base The array to analyze. Only bases that are Java language |
|
* arrays are handled by this resolver. |
|
* @param property The index of the value to be returned. Will be coerced |
|
* into an integer. |
|
* @return If the <code>propertyResolved</code> property of |
|
* <code>ELContext</code> was set to <code>true</code>, then |
|
* the value at the given index or <code>null</code> |
|
* if the index was out of bounds. Otherwise, undefined. |
|
* @throws IllegalArgumentException if the property could not be coerced |
|
* into an integer. |
|
* @throws NullPointerException if context is <code>null</code>. |
|
* @throws ELException if an exception was thrown while performing |
|
* the property or variable resolution. The thrown exception |
|
* must be included as the cause property of this exception, if |
|
* available. |
|
*/ |
|
public Object getValue(ELContext context, |
|
Object base, |
|
Object property) { |
|
|
|
if (context == null) { |
|
throw new NullPointerException(); |
|
} |
|
|
|
if (base != null && base.getClass().isArray()) { |
|
context.setPropertyResolved(base, property); |
|
int index = toInteger (property); |
|
if (index >= 0 && index < Array.getLength(base)) { |
|
return Array.get(base, index); |
|
} |
|
} |
|
return null; |
|
} |
|
|
|
/** |
|
* If the base object is a Java language array, attempts to set the |
|
* value at the given index with the given value. The index is specified |
|
* by the <code>property</code> argument, and coerced into an integer. |
|
* If the coercion could not be performed, an |
|
* <code>IllegalArgumentException</code> is thrown. If the index is |
|
* out of bounds, a <code>PropertyNotFoundException</code> is thrown. |
|
* |
|
* <p>If the base is a Java language array, the |
|
* <code>propertyResolved</code> property of the <code>ELContext</code> |
|
* object must be set to <code>true</code> by this resolver, before |
|
* returning. If this property is not <code>true</code> after this method |
|
* is called, the caller can safely assume no value was set.</p> |
|
* |
|
* <p>If this resolver was constructed in read-only mode, this method will |
|
* always throw <code>PropertyNotWritableException</code>.</p> |
|
* |
|
* @param context The context of this evaluation. |
|
* @param base The array to be modified. Only bases that are Java language |
|
* arrays are handled by this resolver. |
|
* @param property The index of the value to be set. Will be coerced |
|
* into an integer. |
|
* @param val The value to be set at the given index. |
|
* @throws ClassCastException if the class of the specified element |
|
* prevents it from being added to this array. |
|
* @throws NullPointerException if context is <code>null</code>. |
|
* @throws IllegalArgumentException if the property could not be coerced |
|
* into an integer, or if some aspect of the specified element |
|
* prevents it from being added to this array. |
|
* @throws PropertyNotWritableException if this resolver was constructed |
|
* in read-only mode. |
|
* @throws PropertyNotFoundException if the given index is out of |
|
* bounds for this array. |
|
* @throws ELException if an exception was thrown while performing |
|
* the property or variable resolution. The thrown exception |
|
* must be included as the cause property of this exception, if |
|
* available. |
|
*/ |
|
public void setValue(ELContext context, |
|
Object base, |
|
Object property, |
|
Object val) { |
|
|
|
if (context == null) { |
|
throw new NullPointerException(); |
|
} |
|
|
|
if (base != null && base.getClass().isArray()) { |
|
context.setPropertyResolved(base, property); |
|
if (isReadOnly) { |
|
throw new PropertyNotWritableException(); |
|
} |
|
Class<?> type = base.getClass().getComponentType(); |
|
if (val != null && ! type.isAssignableFrom(val.getClass())) { |
|
throw new ClassCastException(); |
|
} |
|
int index = toInteger (property); |
|
if (index < 0 || index >= Array.getLength(base)) { |
|
throw new PropertyNotFoundException(); |
|
} |
|
Array.set(base, index, val); |
|
} |
|
} |
|
|
|
/** |
|
* If the base object is a Java language array, returns whether a call to |
|
* {@link #setValue} will always fail. |
|
* |
|
* <p>If the base is a Java language array, the |
|
* <code>propertyResolved</code> property of the <code>ELContext</code> |
|
* object must be set to <code>true</code> by this resolver, before |
|
* returning. If this property is not <code>true</code> after this method |
|
* is called, the caller should ignore the return value.</p> |
|
* |
|
* <p>If this resolver was constructed in read-only mode, this method will |
|
* always return <code>true</code>. Otherwise, it returns |
|
* <code>false</code>.</p> |
|
* |
|
* @param context The context of this evaluation. |
|
* @param base The array to analyze. Only bases that are a Java language |
|
* array are handled by this resolver. |
|
* @param property The index of the element in the array to return the |
|
* acceptable type for. Will be coerced into an integer, but |
|
* otherwise ignored by this resolver. |
|
* @return If the <code>propertyResolved</code> property of |
|
* <code>ELContext</code> was set to <code>true</code>, then |
|
* <code>true</code> if calling the <code>setValue</code> method |
|
* will always fail or <code>false</code> if it is possible that |
|
* such a call may succeed; otherwise undefined. |
|
* @throws PropertyNotFoundException if the given index is out of |
|
* bounds for this array. |
|
* @throws NullPointerException if context is <code>null</code> |
|
* @throws ELException if an exception was thrown while performing |
|
* the property or variable resolution. The thrown exception |
|
* must be included as the cause property of this exception, if |
|
* available. |
|
*/ |
|
public boolean isReadOnly(ELContext context, |
|
Object base, |
|
Object property) { |
|
|
|
if (context == null) { |
|
throw new NullPointerException(); |
|
} |
|
|
|
if (base != null && base.getClass().isArray()) { |
|
context.setPropertyResolved(true); |
|
int index = toInteger (property); |
|
if (index < 0 || index >= Array.getLength(base)) { |
|
throw new PropertyNotFoundException(); |
|
} |
|
} |
|
return isReadOnly; |
|
} |
|
|
|
/** |
|
* Always returns <code>null</code>, since there is no reason to |
|
* iterate through set set of all integers. |
|
* |
|
* <p>The {@link #getCommonPropertyType} method returns sufficient |
|
* information about what properties this resolver accepts.</p> |
|
* |
|
* @param context The context of this evaluation. |
|
* @param base The array to analyze. Only bases that are a Java language |
|
* array are handled by this resolver. |
|
* @return <code>null</code>. |
|
*/ |
|
public Iterator<FeatureDescriptor> getFeatureDescriptors( |
|
ELContext context, |
|
Object base) { |
|
return null; |
|
} |
|
|
|
/** |
|
* If the base object is a Java language array, returns the most general |
|
* type that this resolver accepts for the <code>property</code> argument. |
|
* Otherwise, returns <code>null</code>. |
|
* |
|
* <p>Assuming the base is an array, this method will always return |
|
* <code>Integer.class</code>. This is because arrays accept integers |
|
* for their index.</p> |
|
* |
|
* @param context The context of this evaluation. |
|
* @param base The array to analyze. Only bases that are a Java language |
|
* array are handled by this resolver. |
|
* @return <code>null</code> if base is not a Java language array; |
|
* otherwise <code>Integer.class</code>. |
|
*/ |
|
public Class<?> getCommonPropertyType(ELContext context, |
|
Object base) { |
|
|
|
if (base != null && base.getClass().isArray()) { |
|
return Integer.class; |
|
} |
|
return null; |
|
} |
|
|
|
private int toInteger(Object p) { |
|
|
|
if (p instanceof Integer) { |
|
return ((Integer) p).intValue(); |
|
} |
|
if (p instanceof Character) { |
|
return ((Character) p).charValue(); |
|
} |
|
if (p instanceof Boolean) { |
|
return ((Boolean) p).booleanValue()? 1: 0; |
|
} |
|
if (p instanceof Number) { |
|
return ((Number) p).intValue(); |
|
} |
|
if (p instanceof String) { |
|
return Integer.parseInt((String) p); |
|
} |
|
throw new IllegalArgumentException(); |
|
} |
|
|
|
private boolean isReadOnly; |
|
} |
|
|
|
|