/*
* 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.types.resources;
import java.io.File;
import java.util.Iterator;
import java.util.Stack;
import java.util.stream.Collectors;
import org.apache.tools.ant.BuildException;
import org.apache.tools.ant.Project;
import org.apache.tools.ant.types.DataType;
import org.apache.tools.ant.types.Resource;
import org.apache.tools.ant.types.ResourceCollection;
/**
* Base class for a ResourceCollection that wraps a single nested
* ResourceCollection.
* @since Ant 1.8.2
*/
public abstract class AbstractResourceCollectionWrapper
extends DataType implements ResourceCollection, Cloneable {
private static final String ONE_NESTED_MESSAGE
= " expects exactly one nested resource collection.";
private ResourceCollection rc;
private boolean cache = true;
/**
* Set whether to cache collections.
* @param b boolean cache flag.
*/
public synchronized void setCache(boolean b) {
cache = b;
}
/**
* Learn whether to cache collections. Default is <code>true</code>.
* @return boolean cache flag.
*/
public synchronized boolean isCache() {
return cache;
}
/**
* Add a ResourceCollection to the container.
* @param c the ResourceCollection to add.
* @throws BuildException on error.
*/
public synchronized void add(ResourceCollection c) throws BuildException {
if (isReference()) {
throw noChildrenAllowed();
}
if (c == null) {
return;
}
if (rc != null) {
throw oneNested();
}
rc = c;
if (Project.getProject(rc) == null) {
Project p = getProject();
if (p != null) {
p.setProjectReference(rc);
}
}
setChecked(false);
}
/**
* Fulfill the ResourceCollection contract.
* @return an Iterator of Resources.
*/
@Override
public final synchronized Iterator<Resource> iterator() {
if (isReference()) {
return ((AbstractResourceCollectionWrapper) getCheckedRef()).iterator();
}
dieOnCircularReference();
return new FailFast(this, createIterator());
}
/**
* Do create an iterator on the resource collection. The creation
* of the iterator is allowed to not be thread safe whereas the iterator
* itself should. The returned iterator will be wrapped into the FailFast
* one.
*
* @return the iterator on the resource collection
*/
protected abstract Iterator<Resource> createIterator();
/**
* Fulfill the ResourceCollection contract.
* @return number of elements as int.
*/
@Override
public synchronized int size() {
if (isReference()) {
return ((AbstractResourceCollectionWrapper) getCheckedRef()).size();
}
dieOnCircularReference();
return getSize();
}
/**
* Do compute the size of the resource collection. The implementation of
* this function is allowed to be not thread safe.
*
* @return size of resource collection.
*/
protected abstract int getSize();
/**
* Fulfill the ResourceCollection contract.
* @return whether this is a filesystem-only resource collection.
*/
public synchronized boolean isFilesystemOnly() {
if (isReference()) {
return ((BaseResourceCollectionContainer) getCheckedRef()).isFilesystemOnly();
}
dieOnCircularReference();
if (rc == null || rc.isFilesystemOnly()) {
return true;
}
/* now check each Resource in case the child only
lets through files from any children IT may have: */
for (Resource r : this) {
if (r.as(FileProvider.class) == null) {
return false;
}
}
return true;
}
/**
* Overrides the version of DataType to recurse on all DataType
* child elements that may have been added.
* @param stk the stack of data types to use (recursively).
* @param p the project to use to dereference the references.
* @throws BuildException on error.
*/
protected synchronized void dieOnCircularReference(Stack<Object> stk, Project p)
throws BuildException {
if (isChecked()) {
return;
}
if (isReference()) {
super.dieOnCircularReference(stk, p);
} else {
if (rc instanceof DataType) {
pushAndInvokeCircularReferenceCheck((DataType) rc, stk, p);
}
setChecked(true);
}
}
/**
* Get the nested ResourceCollection.
* @return a ResourceCollection.
* @throws BuildException if no nested ResourceCollection has been provided.
*/
protected final synchronized ResourceCollection getResourceCollection() {
dieOnCircularReference();
if (rc == null) {
throw oneNested();
}
return rc;
}
/**
* Format this AbstractResourceCollectionWrapper as a String.
* @return a descriptive <code>String</code>.
*/
@Override
public synchronized String toString() {
if (isReference()) {
return getCheckedRef().toString();
}
if (isEmpty()) {
return "";
}
return stream().map(Object::toString)
.collect(Collectors.joining(File.pathSeparator));
}
private BuildException oneNested() {
return new BuildException(super.toString() + ONE_NESTED_MESSAGE);
}
}