src/main/org/apache/tools/ant/types/resources/MappedResource.java

/*
 *  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
 *
 *      https://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 org.apache.tools.ant.types.Reference;
import org.apache.tools.ant.types.Resource;
import org.apache.tools.ant.util.FileNameMapper;

/**
 * A decorator around a different resource that uses a mapper to
 * dynamically remap the resource's name.
 *
 * <p>Strips the FileProvider interface from decorated resources since
 * it may be used to circumvent name mapping.</p>
 *
 * @since Ant 1.8.0
 */
public class MappedResource extends ResourceDecorator {
    private final FileNameMapper mapper;

    /**
     * Wraps an existing resource.
     * @param r Resource to wrap
     * @param m FileNameMapper that handles mapping
     */
    public MappedResource(Resource r, FileNameMapper m) {
        super(r);
        mapper = m;
    }

    /**
     * Maps the name.
     */
    @Override
    public String getName() {
        String name = getResource().getName();
        if (isReference()) {
            return name;
        }
        String[] mapped = mapper.mapFileName(name);
        return mapped != null && mapped.length > 0 ? mapped[0] : null;
    }

    /**
     * Not really supported since mapper is never null.
     * @param r reference to set
     */
    @Override
    public void setRefid(Reference r) {
        if (mapper != null) {
            throw noChildrenAllowed();
        }
        super.setRefid(r);
    }

    /**
     * Suppress FileProvider
     * @param clazz the type to implement
     */
    @Override
    public <T> T as(Class<T> clazz) {
        return FileProvider.class.isAssignableFrom(clazz)
                ? null : getResource().as(clazz);
    }

    /**
     * Get the hash code for this Resource.
     * @since Ant 1.8.1
     */
    @Override
    public int hashCode() {
        String n = getName();
        return n == null ? super.hashCode() : n.hashCode();
    }

    /**
     * Equality check based on the resource's name in addition to the
     * resource itself.
     * @since Ant 1.8.1
     */
    @Override
    public boolean equals(Object other) {
        if (other == null || other.getClass() != getClass()) {
            return false;
        }
        MappedResource m = (MappedResource) other;
        String myName = getName();
        String otherName = m.getName();
        return (myName == null ? otherName == null : myName.equals(otherName))
            && getResource().equals(m.getResource());
    }

    @Override
    public String toString() {
        if (isReference()) {
            return getRef().toString();
        }
        return getName();
    }

}