| /* |
| * The Apache Software License, Version 1.1 |
| * |
| * Copyright (c) 2002 The Apache Software Foundation. All rights |
| * reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in |
| * the documentation and/or other materials provided with the |
| * distribution. |
| * |
| * 3. The end-user documentation included with the redistribution, if |
| * any, must include the following acknowlegement: |
| * "This product includes software developed by the |
| * Apache Software Foundation (http://www.apache.org/)." |
| * Alternately, this acknowlegement may appear in the software itself, |
| * if and wherever such third-party acknowlegements normally appear. |
| * |
| * 4. The names "The Jakarta Project", "Ant", and "Apache Software |
| * Foundation" must not be used to endorse or promote products derived |
| * from this software without prior written permission. For written |
| * permission, please contact apache@apache.org. |
| * |
| * 5. Products derived from this software may not be called "Apache" |
| * nor may "Apache" appear in their names without prior written |
| * permission of the Apache Group. |
| * |
| * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED |
| * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
| * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE |
| * DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR |
| * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF |
| * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND |
| * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, |
| * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT |
| * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| * SUCH DAMAGE. |
| * ==================================================================== |
| * |
| * This software consists of voluntary contributions made by many |
| * individuals on behalf of the Apache Software Foundation. For more |
| * information on the Apache Software Foundation, please see |
| * <http://www.apache.org/>. |
| */ |
| package org.apache.ant.antcore.execution; |
| import java.lang.reflect.Constructor; |
| import java.lang.reflect.InvocationTargetException; |
| import java.lang.reflect.Method; |
| import java.util.HashMap; |
| import java.util.Iterator; |
| import java.util.Map; |
| import org.apache.ant.common.antlib.Converter; |
| import org.apache.ant.common.util.ExecutionException; |
| |
| /** |
| * A reflector is used to set attributes and add nested elements to an |
| * instance of an object using reflection. It is the result of class |
| * introspection. |
| * |
| * @author Conor MacNeill |
| * @created 19 January 2002 |
| */ |
| public class Reflector implements Setter { |
| |
| /** |
| * An element adder is used to add an instance of an element to an of an |
| * object. The object being added will have been fully configured by Ant |
| * prior to calling this method. |
| * |
| * @author Conor MacNeill |
| * @created 19 January 2002 |
| */ |
| private interface ElementAdder { |
| /** |
| * Add an object to the this container object |
| * |
| * @param container the object to which the element is the be added |
| * @param obj an instance of the nested element |
| * @exception InvocationTargetException if the method cannot be |
| * invoked |
| * @exception IllegalAccessException if the method cannot be invoked |
| */ |
| void add(Object container, Object obj) |
| throws InvocationTargetException, IllegalAccessException; |
| } |
| |
| /** |
| * Element Creator's a factory method provided by an Ant Library |
| * Component for creating its own nested element instances. These |
| * methods are now deprecated. It is better to use the add style methods |
| * and support polymorphic interfaces. |
| * |
| * @author Conor MacNeill |
| * @created 31 January 2002 |
| */ |
| private interface ElementCreator { |
| /** |
| * Create a nested element object for the given container object |
| * |
| * @param container the object in which the nested element is to be |
| * created. |
| * @return the nested element. |
| * @exception InvocationTargetException if the create method fails |
| * @exception IllegalAccessException if the create method cannot be |
| * accessed |
| * @exception InstantiationException if the nested element instance |
| * cannot be created. |
| */ |
| Object create(Object container) |
| throws InvocationTargetException, IllegalAccessException, |
| InstantiationException; |
| } |
| |
| |
| /** The method used to add content to the element */ |
| private Method addTextMethod; |
| |
| /** the list of attribute setters indexed by their property name */ |
| private Map attributeSetters = new HashMap(); |
| |
| /** |
| * A list of the Java class or interface accetpted by each element adder |
| * indexed by the element name |
| */ |
| private Map elementTypes = new HashMap(); |
| |
| /** the collection of element adders indexed by their element names */ |
| private Map elementAdders = new HashMap(); |
| |
| /** the collection of element creators indexed by their element names */ |
| private Map elementCreators = new HashMap(); |
| |
| /** |
| * Set an attribute value on an object |
| * |
| * @param obj the object on which the value is being set |
| * @param attributeName the name of the attribute |
| * @param value the string represenation of the attribute's value |
| * @exception ExecutionException if the object does not support the |
| * attribute or the object has a problem setting the value |
| */ |
| public void setAttribute(Object obj, String attributeName, |
| String value) |
| throws ExecutionException { |
| String name = attributeName.toLowerCase(); |
| AttributeSetter as |
| = (AttributeSetter) attributeSetters.get(name); |
| if (as == null) { |
| throw new ExecutionException("Class " + obj.getClass().getName() |
| + " doesn't support the \"" + attributeName + "\" attribute"); |
| } |
| try { |
| as.set(obj, value); |
| } catch (IllegalAccessException e) { |
| // impossible as getMethods should only return public methods |
| throw new ExecutionException(e); |
| } catch (InvocationTargetException ite) { |
| Throwable t = ite.getTargetException(); |
| if (t instanceof ExecutionException) { |
| throw (ExecutionException) t; |
| } |
| throw new ExecutionException(t); |
| } |
| } |
| |
| /** |
| * Set the method used to add content to the element |
| * |
| * @param addTextMethod the new addTextMethod value |
| */ |
| public void setAddTextMethod(Method addTextMethod) { |
| this.addTextMethod = addTextMethod; |
| } |
| |
| /** |
| * Get the type of the given nested element |
| * |
| * @param elementName the nested element whose type is desired |
| * @return the class instance representing the type of the element adder |
| */ |
| public Class getType(String elementName) { |
| return (Class) elementTypes.get(elementName); |
| } |
| |
| /** |
| * Adds PCDATA to the element |
| * |
| * @param obj the instance whose content is being provided |
| * @param text the required content |
| * @exception ExecutionException if the object does not support |
| * contentor the object has a problem setting the content |
| */ |
| public void addText(Object obj, String text) |
| throws ExecutionException { |
| |
| if (addTextMethod == null) { |
| throw new ExecutionException("Class " + obj.getClass().getName() + |
| " doesn't support content"); |
| } |
| try { |
| addTextMethod.invoke(obj, new String[]{text}); |
| } catch (IllegalAccessException ie) { |
| // impossible as getMethods should only return public methods |
| throw new ExecutionException(ie); |
| } catch (InvocationTargetException ite) { |
| Throwable t = ite.getTargetException(); |
| if (t instanceof ExecutionException) { |
| throw (ExecutionException) t; |
| } |
| throw new ExecutionException(t); |
| } |
| } |
| |
| /** |
| * Add an element to the given object |
| * |
| * @param obj The object to which the element is being added |
| * @param elementName the name of the element |
| * @param value the object to be added - the nested element |
| * @exception ExecutionException if the object does not support content |
| * or the object has a problem setting the content |
| */ |
| public void addElement(Object obj, String elementName, Object value) |
| throws ExecutionException { |
| String name = elementName.toLowerCase(); |
| ElementAdder adder = (ElementAdder) elementAdders.get(name); |
| if (adder == null) { |
| throw new ExecutionException("Class " + obj.getClass().getName() |
| + " doesn't support the \"" + elementName |
| + "\" nested element"); |
| } |
| try { |
| adder.add(obj, value); |
| } catch (IllegalAccessException ie) { |
| // impossible as getMethods should only return public methods |
| throw new ExecutionException(ie); |
| } catch (InvocationTargetException ite) { |
| Throwable t = ite.getTargetException(); |
| if (t instanceof ExecutionException) { |
| throw (ExecutionException) t; |
| } |
| throw new ExecutionException(t); |
| } |
| |
| } |
| |
| /** |
| * Create a nested element using the object's element factory method. |
| * |
| * @param container the object in which the nested element is required. |
| * @param elementName the name of the nested element |
| * @return the new instance of the nested element |
| * @exception ExecutionException if the nested element cannot be |
| * created. |
| */ |
| public Object createElement(Object container, String elementName) |
| throws ExecutionException { |
| |
| ElementCreator creator |
| = (ElementCreator) elementCreators.get(elementName.toLowerCase()); |
| if (creator == null) { |
| throw new ExecutionException("Class " |
| + container.getClass().getName() |
| + " doesn't support the \"" + elementName |
| + "\" nested element"); |
| } |
| |
| try { |
| return creator.create(container); |
| } catch (IllegalAccessException e) { |
| // impossible as getMethods should only return public methods |
| throw new ExecutionException(e); |
| } catch (InstantiationException e) { |
| // impossible as getMethods should only return public methods |
| throw new ExecutionException(e); |
| } catch (InvocationTargetException e) { |
| Throwable t = e.getTargetException(); |
| if (t instanceof ExecutionException) { |
| throw (ExecutionException) t; |
| } |
| throw new ExecutionException(t); |
| } |
| } |
| |
| /** |
| * Indicate if the class assocated with this reflector supports the |
| * addition of text content. |
| * |
| * @return true if the class supports an addText method |
| */ |
| public boolean supportsText() { |
| return addTextMethod != null; |
| } |
| |
| /** |
| * Indicate if the class assocated with this reflector supports the |
| * given attribute |
| * |
| * @param attributeName the name of the attribute |
| * @return true if the given attribute is supported |
| */ |
| public boolean supportsAttribute(String attributeName) { |
| return attributeSetters.containsKey(attributeName.toLowerCase()); |
| } |
| |
| /** |
| * Determine if the class associated with this reflector supports a |
| * particular nested element via a create factory method |
| * |
| * @param elementName the name of the element |
| * @return true if the class supports creation of that element |
| */ |
| public boolean supportsNestedCreator(String elementName) { |
| return elementCreators.containsKey(elementName.toLowerCase()); |
| } |
| |
| /** |
| * Determine if the class associated with this reflector supports a |
| * particular nested element via an add method |
| * |
| * @param elementName the name of the element |
| * @return true if the class supports addition of that element |
| */ |
| public boolean supportsNestedAdder(String elementName) { |
| return elementAdders.containsKey(elementName.toLowerCase()); |
| } |
| |
| /** |
| * Add an attribute setter for the given property. The setter will only |
| * be added if it does not override a higher priorty setter |
| * |
| * @param attributeName the name of the attribute that the setter operates |
| * upon. |
| * @param setter the AttribnuteSetter instance to use. |
| */ |
| private void addAttributeSetter(String attributeName, |
| AttributeSetter setter) { |
| String name = attributeName.toLowerCase(); |
| AttributeSetter currentSetter |
| = (AttributeSetter) attributeSetters.get(name); |
| if (currentSetter != null) { |
| // there is a setter, is it lower down in the class hierarchy |
| int currentDepth = currentSetter.getDepth(); |
| if (currentDepth < setter.getDepth()) { |
| return; |
| } else if (currentDepth == setter.getDepth()) { |
| // now check the types |
| Class currentType = currentSetter.getType(); |
| if (currentType != String.class) { |
| return; |
| } |
| } |
| } |
| attributeSetters.put(name, setter); |
| } |
| |
| |
| /** |
| * Determine if the class associated with this reflector supports a |
| * particular nested element |
| * |
| * @param elementName the name of the element |
| * @return true if the class supports the given type of nested element |
| */ |
| public boolean supportsNestedElement(String elementName) { |
| return supportsNestedAdder(elementName) |
| || supportsNestedCreator(elementName); |
| } |
| |
| /** |
| * Add a method to the reflector for setting an attribute value |
| * |
| * @param m the method, obtained by introspection. |
| * @param depth the depth of this method's declaration in the class |
| * hierarchy |
| * @param propertyName the property name the method will set. |
| * @param converters A map of converter classes used to convert strings |
| * to different types. |
| */ |
| public void addAttributeMethod(Method m, int depth, |
| String propertyName, Map converters) { |
| Class type = m.getParameterTypes()[0]; |
| |
| if (converters != null && converters.containsKey(type)) { |
| // we have a converter to use to convert the String |
| // value into something the set method expects. |
| Converter converter = (Converter) converters.get(type); |
| addConvertingSetter(m, depth, propertyName, converter); |
| return; |
| } |
| |
| if (type.equals(String.class)) { |
| addAttributeSetter(propertyName, new AttributeSetter(m, depth)); |
| return; |
| } |
| |
| try { |
| final Constructor c = |
| type.getConstructor(new Class[]{java.lang.String.class}); |
| addAttributeSetter(propertyName, new AttributeSetter(m, depth, c)); |
| return; |
| } catch (NoSuchMethodException nme) { |
| // ignore |
| } |
| |
| if (converters != null) { |
| // desparate by now - try top find a converter which handles a super |
| // class of this type and which supports subclass instantiation |
| for (Iterator i = converters.keySet().iterator(); i.hasNext();) { |
| Class converterType = (Class) i.next(); |
| if (converterType.isAssignableFrom(type)) { |
| // could be a candidate |
| Converter converter |
| = (Converter) converters.get(converterType); |
| if (converter.canConvertSubType(type)) { |
| addConvertingSetter(m, depth, propertyName, converter); |
| return; |
| } |
| } |
| } |
| } |
| } |
| |
| /** |
| * Add an element adder method to the list of element adders in the |
| * reflector |
| * |
| * @param m the adder method |
| * @param elementName The name of the element for which this adder works |
| */ |
| public void addElementMethod(final Method m, String elementName) { |
| final Class type = m.getParameterTypes()[0]; |
| elementTypes.put(elementName, type); |
| elementAdders.put(elementName.toLowerCase(), |
| new ElementAdder() { |
| public void add(Object container, Object obj) |
| throws InvocationTargetException, IllegalAccessException { |
| m.invoke(container, new Object[]{obj}); |
| } |
| }); |
| } |
| |
| |
| /** |
| * Add a create factory method. |
| * |
| * @param m the create method |
| * @param elementName the name of the nested element the create method |
| * supports. |
| */ |
| public void addCreateMethod(final Method m, String elementName) { |
| elementCreators.put(elementName.toLowerCase(), |
| new ElementCreator() { |
| public Object create(Object container) |
| throws InvocationTargetException, IllegalAccessException { |
| return m.invoke(container, new Object[]{}); |
| } |
| }); |
| } |
| |
| /** |
| * Add an attribute setter with an associated converter |
| * |
| * @param m the attribute setter method |
| * @param depth the depth of this method's declaration in the class |
| * hierarchy |
| * @param propertyName the name of the attribute this method supports |
| * @param converter the converter to be used to construct the value |
| * expected by the method. |
| */ |
| private void addConvertingSetter(Method m, int depth, |
| String propertyName, Converter converter) { |
| addAttributeSetter(propertyName, |
| new AttributeSetter(m, depth, converter)); |
| } |
| } |
| |