| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You 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 org.apache.tools.ant.filters.util; |
| |
| import java.io.FilterReader; |
| import java.io.IOException; |
| import java.io.Reader; |
| import java.lang.reflect.Constructor; |
| import java.lang.reflect.InvocationTargetException; |
| import java.util.ArrayList; |
| import java.util.Iterator; |
| import java.util.List; |
| import java.util.Vector; |
| |
| import org.apache.tools.ant.AntClassLoader; |
| import org.apache.tools.ant.BuildException; |
| import org.apache.tools.ant.Project; |
| import org.apache.tools.ant.filters.BaseFilterReader; |
| import org.apache.tools.ant.filters.ChainableReader; |
| import org.apache.tools.ant.types.AntFilterReader; |
| import org.apache.tools.ant.types.FilterChain; |
| import org.apache.tools.ant.types.Parameter; |
| import org.apache.tools.ant.types.Parameterizable; |
| import org.apache.tools.ant.types.Path; |
| import org.apache.tools.ant.util.FileUtils; |
| |
| /** |
| * Process a FilterReader chain. |
| * |
| */ |
| public final class ChainReaderHelper { |
| |
| // default buffer size |
| private static final int DEFAULT_BUFFER_SIZE = 8192; |
| // CheckStyle:VisibilityModifier OFF - bc |
| /** |
| * The primary reader to which the reader chain is to be attached. |
| */ |
| public Reader primaryReader; |
| |
| /** |
| * The size of the buffer to be used. |
| */ |
| public int bufferSize = DEFAULT_BUFFER_SIZE; |
| |
| /** |
| * Chain of filters |
| */ |
| public Vector<FilterChain> filterChains = new Vector<FilterChain>(); |
| |
| /** The Ant project */ |
| private Project project = null; |
| |
| // CheckStyle:VisibilityModifier ON |
| |
| /** |
| * Sets the primary reader |
| * @param rdr the reader object |
| */ |
| public void setPrimaryReader(Reader rdr) { |
| primaryReader = rdr; |
| } |
| |
| /** |
| * Set the project to work with |
| * @param project the current project |
| */ |
| public void setProject(final Project project) { |
| this.project = project; |
| } |
| |
| /** |
| * Get the project |
| * |
| * @return the current project |
| */ |
| public Project getProject() { |
| return project; |
| } |
| |
| /** |
| * Sets the buffer size to be used. Defaults to 8192, |
| * if this method is not invoked. |
| * @param size the buffer size to use |
| */ |
| public void setBufferSize(int size) { |
| bufferSize = size; |
| } |
| |
| /** |
| * Sets the collection of filter reader sets |
| * |
| * @param fchain the filter chains collection |
| */ |
| public void setFilterChains(Vector<FilterChain> fchain) { |
| filterChains = fchain; |
| } |
| |
| /** |
| * Assemble the reader |
| * @return the assembled reader |
| * @exception BuildException if an error occurs |
| */ |
| public Reader getAssembledReader() throws BuildException { |
| if (primaryReader == null) { |
| throw new BuildException("primaryReader must not be null."); |
| } |
| |
| Reader instream = primaryReader; |
| final int filterReadersCount = filterChains.size(); |
| final Vector<Object> finalFilters = new Vector<Object>(); |
| final ArrayList<AntClassLoader> classLoadersToCleanUp = |
| new ArrayList<AntClassLoader>(); |
| |
| for (int i = 0; i < filterReadersCount; i++) { |
| final FilterChain filterchain = |
| filterChains.elementAt(i); |
| final Vector<Object> filterReaders = filterchain.getFilterReaders(); |
| final int readerCount = filterReaders.size(); |
| for (int j = 0; j < readerCount; j++) { |
| finalFilters.addElement(filterReaders.elementAt(j)); |
| } |
| } |
| |
| final int filtersCount = finalFilters.size(); |
| |
| if (filtersCount > 0) { |
| boolean success = false; |
| try { |
| for (int i = 0; i < filtersCount; i++) { |
| Object o = finalFilters.elementAt(i); |
| |
| if (o instanceof AntFilterReader) { |
| instream = |
| expandReader((AntFilterReader) finalFilters.elementAt(i), |
| instream, classLoadersToCleanUp); |
| } else if (o instanceof ChainableReader) { |
| setProjectOnObject(o); |
| instream = ((ChainableReader) o).chain(instream); |
| setProjectOnObject(instream); |
| } |
| } |
| success = true; |
| } finally { |
| if (!success && classLoadersToCleanUp.size() > 0) { |
| cleanUpClassLoaders(classLoadersToCleanUp); |
| } |
| } |
| } |
| final Reader finalReader = instream; |
| return classLoadersToCleanUp.size() == 0 ? finalReader |
| : new FilterReader(finalReader) { |
| public void close() throws IOException { |
| FileUtils.close(in); |
| cleanUpClassLoaders(classLoadersToCleanUp); |
| } |
| protected void finalize() throws Throwable { |
| try { |
| close(); |
| } finally { |
| super.finalize(); |
| } |
| } |
| }; |
| } |
| |
| /** |
| * helper method to set the project on an object. |
| * the reflection setProject does not work for anonymous/protected/private |
| * classes, even if they have public methods. |
| */ |
| private void setProjectOnObject(Object obj) { |
| if (project == null) { |
| return; |
| } |
| if (obj instanceof BaseFilterReader) { |
| ((BaseFilterReader) obj).setProject(project); |
| return; |
| } |
| project.setProjectReference(obj); |
| } |
| |
| /** |
| * Deregisters Classloaders from the project so GC can remove them later. |
| */ |
| private static void cleanUpClassLoaders(List<AntClassLoader> loaders) { |
| for (Iterator<AntClassLoader> it = loaders.iterator(); it.hasNext();) { |
| it.next().cleanup(); |
| } |
| } |
| |
| /** |
| * Read data from the reader and return the |
| * contents as a string. |
| * @param rdr the reader object |
| * @return the contents of the file as a string |
| * @exception IOException if an error occurs |
| */ |
| public String readFully(Reader rdr) |
| throws IOException { |
| return FileUtils.readFully(rdr, bufferSize); |
| } |
| |
| /** |
| * Creates and parameterizes a new FilterReader from a |
| * <filterreader> element. |
| * |
| * @since Ant 1.8.0 |
| */ |
| private Reader expandReader(final AntFilterReader filter, |
| final Reader ancestor, |
| final List<AntClassLoader> classLoadersToCleanUp) { |
| final String className = filter.getClassName(); |
| final Path classpath = filter.getClasspath(); |
| final Project pro = filter.getProject(); |
| if (className != null) { |
| try { |
| Class<?> clazz = null; |
| if (classpath == null) { |
| clazz = Class.forName(className); |
| } else { |
| AntClassLoader al = pro.createClassLoader(classpath); |
| classLoadersToCleanUp.add(al); |
| clazz = Class.forName(className, true, al); |
| } |
| if (clazz != null) { |
| if (!FilterReader.class.isAssignableFrom(clazz)) { |
| throw new BuildException(className + " does not extend" |
| + " java.io.FilterReader"); |
| } |
| final Constructor<?>[] constructors = clazz.getConstructors(); |
| int j = 0; |
| boolean consPresent = false; |
| for (; j < constructors.length; j++) { |
| Class<?>[] types = constructors[j].getParameterTypes(); |
| if (types.length == 1 |
| && types[0].isAssignableFrom(Reader.class)) { |
| consPresent = true; |
| break; |
| } |
| } |
| if (!consPresent) { |
| throw new BuildException(className + " does not define" |
| + " a public constructor" |
| + " that takes in a Reader" |
| + " as its single argument."); |
| } |
| final Reader[] rdr = {ancestor}; |
| Reader instream = |
| (Reader) constructors[j].newInstance((Object[]) rdr); |
| setProjectOnObject(instream); |
| if (Parameterizable.class.isAssignableFrom(clazz)) { |
| final Parameter[] params = filter.getParams(); |
| ((Parameterizable) instream).setParameters(params); |
| } |
| return instream; |
| } |
| } catch (final ClassNotFoundException cnfe) { |
| throw new BuildException(cnfe); |
| } catch (final InstantiationException ie) { |
| throw new BuildException(ie); |
| } catch (final IllegalAccessException iae) { |
| throw new BuildException(iae); |
| } catch (final InvocationTargetException ite) { |
| throw new BuildException(ite); |
| } |
| } |
| // Ant 1.7.1 and earlier ignore <filterreader> without a |
| // classname attribute, not sure this is a good idea - |
| // backwards compatibility makes it hard to change, though. |
| return ancestor; |
| } |
| } |