| /******************************************************************************* |
| * Copyright (c) 2001, 2008 IBM Corporation and others. |
| * All rights reserved. This program and the accompanying materials |
| * are made available under the terms of the Eclipse Public License v1.0 |
| * which accompanies this distribution, and is available at |
| * http://www.eclipse.org/legal/epl-v10.html |
| * |
| * Contributors: |
| * IBM Corporation - initial API and implementation |
| *******************************************************************************/ |
| package org.eclipse.wst.validation.internal; |
| |
| import java.text.MessageFormat; |
| |
| import org.eclipse.core.resources.IResource; |
| |
| /** |
| * Represents a type filter tag in a validator's plugin.xml file. e.g. <filter |
| * objectClass="com.ibm.foo.MyClass"> Then this class would store the "com.ibm.foo.MyClass", and |
| * provide the "instanceof" matching functionality. |
| */ |
| public class ValidatorTypeFilter { |
| private Class _typeFilterClass; |
| private String _mustImplementClass; // the type set in setTypeFilter must implement the |
| |
| // class/interface identified by this fully-qualified |
| // Java string. |
| |
| ValidatorTypeFilter() { |
| //default |
| } |
| |
| ValidatorTypeFilter(String mustImplementClass) { |
| setMustImplementClass(mustImplementClass); |
| } |
| |
| /** |
| * Type filters are allowed only for certain types of classes. This method returns the name of |
| * the class which this type must implement before it can be a filter. |
| */ |
| String getMustImplementClass() { |
| return _mustImplementClass; |
| } |
| |
| /** |
| * Return the type filter as a java.lang.Class object. |
| */ |
| Class getTypeFilterClass() { |
| return _typeFilterClass; |
| } |
| |
| /** |
| * Returns true if the resource passed in either an instance of the type filter class, or if |
| * there is no type filter class defined in plugin.xml. |
| */ |
| public boolean isApplicableType(IResource resource) { |
| // If type filter is null, means filter out no types. |
| // Otherwise, return true only if the given type is an instance of |
| // the type filter. |
| if (_typeFilterClass == null) |
| return true; |
| |
| // If the resource is an instance of the type filter class. |
| return isInstance(resource.getClass(), _typeFilterClass); |
| } |
| |
| /** |
| * Checks if filterClass is a parent (interface or superclass) of objectClass. |
| */ |
| boolean isInstance(Class objectClass, Class filterClass) { |
| // The java.lang.Class.isInstance call doesn't check interfaces fully. |
| // i.e., if I have two interfaces, A and B, and B extends A but |
| // doesn't implement A, then the isInstance call will return false. |
| // |
| // So, instead of using Class.isInstance, do the checking myself. |
| for (Class cl = objectClass; cl != null; cl = cl.getSuperclass()) { |
| if (cl.getName().equals(filterClass.getName())) { |
| return true; |
| } |
| Class[] clInterfaces = cl.getInterfaces(); |
| for (int i = 0; i < clInterfaces.length; i++) { |
| if (clInterfaces[i].getName().equals(filterClass.getName())) { |
| return true; |
| } |
| return isInstance(clInterfaces[i], filterClass); |
| } |
| } |
| return false; |
| } |
| |
| /** |
| * Type filters are allowed only for certain types of classes. This method sets the name of the |
| * class which this type must implement before it can be a filter. |
| */ |
| void setMustImplementClass(String className) { |
| _mustImplementClass = className; |
| } |
| |
| /** |
| * If the filter implements the mustImplementClass (in ValidatorFilter's case, IResource), then |
| * this is a valid filter, and store the filter value. |
| */ |
| void setTypeFilter(String filter) { |
| Class filterClass = null; |
| Class mustImplementClass = null; |
| |
| if (filter == null) { |
| _typeFilterClass = null; |
| return; |
| } |
| |
| try { |
| filterClass = Class.forName(filter); |
| if (getMustImplementClass() != null) { |
| mustImplementClass = Class.forName(getMustImplementClass()); |
| |
| // If the filter class is not an instance of mustImplementClass |
| if (!isInstance(filterClass, mustImplementClass)) { |
| _typeFilterClass = null; |
| if (Tracing.isLogging()) { |
| String result = MessageFormat.format(ResourceHandler.getExternalizedMessage(ResourceConstants.VBF_EXC_INVALID_TYPE_FILTER), |
| new Object[]{filter, getMustImplementClass()}); |
| Tracing.log("ValidatorTypeFilter-01: ", result); //$NON-NLS-1$ |
| } |
| } |
| } |
| } catch (ClassNotFoundException exc) { |
| _typeFilterClass = null; |
| if (Tracing.isLogging()) { |
| Tracing.log("ValidatorTypeFilter-02: The class named " + filter + //$NON-NLS-1$ |
| " cannot be instantiated because it does not exist. Check the spelling of the name, " + //$NON-NLS-1$ |
| "in the validator's plugin.xml contribution, and try restarting eclipse again."); //$NON-NLS-1$ |
| } |
| return; |
| } |
| _typeFilterClass = filterClass; |
| } |
| |
| public String toString() { |
| StringBuffer buffer = new StringBuffer(); |
| buffer.append("TypeFilter:"); //$NON-NLS-1$ |
| buffer.append(" _typeFilterClass = " + _typeFilterClass.getName()); //$NON-NLS-1$ |
| buffer.append(" _mustImplementClass = " + _mustImplementClass); //$NON-NLS-1$ |
| return buffer.toString(); |
| } |
| } |