initial, completely non-functional mapped resource. There must be a better way to support the optional resoucre interfaces!

git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@714053 13f79535-47bb-0310-9956-ffa450edef68

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

@@ -0,0 +1,324 @@
+/*
+ *  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.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+import org.apache.tools.ant.types.Reference;
+import org.apache.tools.ant.types.Resource;
+
+/**
+ * A decorator around a different resource that uses a mapper to
+ * dynamically remap the resource's name.
+ *
+ * <p>Does not change any of the other methods, in particular
+ * getFile() does not map the file name.</p>
+ *
+ * <p>Overwrites all setters to throw exceptions.</p>
+ *
+ * @since Ant 1.8.0
+ */
+public class MappedResource extends Resource {
+    private final Resource wrapped;
+
+    // should only be instantiated via factory, this also means we
+    // don't have to think about being a reference to a different
+    // resource
+
+    /**
+     * Wraps an existing resource.
+     */
+    protected MappedResource(Resource r) {
+        wrapped = r;
+    }
+
+    /**
+     * Maps the name.
+     */
+    public String getName() {
+        return wrapped.getName();
+    }
+
+    /**
+     * Not supported.
+     */
+    public void setName(String name) {
+        throw new UnsupportedOperationException();
+    }
+
+    /**
+     * delegated to the wrapped resource.
+     */
+    public boolean isExists() {
+        return wrapped.isExists();
+    }
+
+    /**
+     * Not supported.
+     */
+    public void setExists(boolean exists) {
+        throw new UnsupportedOperationException();
+    }
+
+    /**
+     * delegated to the wrapped resource.
+     */
+    public long getLastModified() {
+        return wrapped.getLastModified();
+    }
+
+    /**
+     * Not supported.
+     */
+    public void setLastModified(long lastmodified) {
+        throw new UnsupportedOperationException();
+    }
+
+    /**
+     * delegated to the wrapped resource.
+     */
+    public boolean isDirectory() {
+        return wrapped.isDirectory();
+    }
+
+    /**
+     * Not supported.
+     */
+    public void setDirectory(boolean directory) {
+        throw new UnsupportedOperationException();
+    }
+
+    /**
+     * delegated to the wrapped resource.
+     */
+    public long getSize() {
+        return wrapped.getSize();
+    }
+
+    /**
+     * Not supported.
+     */
+    public void setSize(long size) {
+        throw new UnsupportedOperationException();
+    }
+
+    /**
+     * delegated to the wrapped resource.
+     */
+    public InputStream getInputStream() throws IOException {
+        return wrapped.getInputStream();
+    }
+
+    /**
+     * delegated to the wrapped resource.
+     */
+    public OutputStream getOutputStream() throws IOException {
+        return wrapped.getOutputStream();
+    }
+
+    /**
+     * delegated to the wrapped resource.
+     */
+    public boolean isFilesystemOnly() {
+        return wrapped.isFilesystemOnly();
+    }
+
+    public String toString() {
+        return "mapped " + wrapped.toString();
+    }
+
+    /**
+     * Not supported.
+     */
+    public void setRefid(Reference r) {
+        throw new UnsupportedOperationException();
+    }
+
+    public static MappedResource map(Resource r) {
+        if (r instanceof FileProvider) {
+            if (r instanceof Touchable) {
+                if (r instanceof Appendable) {
+                    // most probably FileResource
+                    return new AppendableTouchableFileProviderMR(r);
+                }
+                return new TouchableFileProviderMR(r);
+            }
+            if (r instanceof Appendable) {
+                return new AppendableFileProviderMR(r);
+            }
+            return new FileProviderMR(r);
+        }
+        if (r instanceof Touchable) {
+            if (r instanceof Appendable) {
+                return new AppendableTouchableMR(r);
+            }
+            return new TouchableMR(r);
+        }
+        if (r instanceof Appendable) {
+            return new AppendableMR(r);
+        }
+        // no special interface
+        return new MappedResource(r);
+    }
+
+    private static class FileProviderMR extends MappedResource
+        implements FileProvider {
+        private final FileProvider p;
+
+        protected FileProviderMR(Resource r) {
+            super(r);
+            if (!(r instanceof FileProvider)) {
+                throw new IllegalArgumentException("trying to wrap something "
+                                                   + "that is not a "
+                                                   + " FileProvider");
+            }
+            p = (FileProvider) r;
+        }
+
+        /**
+         * delegated to the wrapped resource.
+         */
+        public File getFile() {
+            return p.getFile();
+        }
+    }
+
+    private static class TouchableMR extends MappedResource
+        implements Touchable {
+        private final Touchable t;
+
+        protected TouchableMR(Resource r) {
+            super(r);
+            if (!(r instanceof Touchable)) {
+                throw new IllegalArgumentException("trying to wrap something "
+                                                   + "that is not a "
+                                                   + " Touchable");
+            }
+            t = (Touchable) r;
+        }
+
+        /**
+         * delegated to the wrapped resource.
+         */
+        public void touch(long m) {
+            t.touch(m);
+        }
+    }
+
+    private static class AppendableMR extends MappedResource
+        implements Appendable {
+        private final Appendable a;
+
+        protected AppendableMR(Resource r) {
+            super(r);
+            if (!(r instanceof Appendable)) {
+                throw new IllegalArgumentException("trying to wrap something "
+                                                   + "that is not a "
+                                                   + " Appendable");
+            }
+            a = (Appendable) r;
+        }
+
+        public OutputStream getAppendOutputStream() throws IOException {
+            return a.getAppendOutputStream();
+        }
+    }
+
+    private static class TouchableFileProviderMR extends FileProviderMR
+        implements Touchable {
+        private final Touchable t;
+
+        protected TouchableFileProviderMR(Resource r) {
+            super(r);
+            if (!(r instanceof Touchable)) {
+                throw new IllegalArgumentException("trying to wrap something "
+                                                   + "that is not a "
+                                                   + " Touchable");
+            }
+            t = (Touchable) r;
+        }
+
+        /**
+         * delegated to the wrapped resource.
+         */
+        public void touch(long m) {
+            t.touch(m);
+        }
+    }
+
+    private static class AppendableFileProviderMR extends FileProviderMR
+        implements Appendable {
+        private final Appendable a;
+
+        protected AppendableFileProviderMR(Resource r) {
+            super(r);
+            if (!(r instanceof Appendable)) {
+                throw new IllegalArgumentException("trying to wrap something "
+                                                   + "that is not a "
+                                                   + " Appendable");
+            }
+            a = (Appendable) r;
+        }
+
+        public OutputStream getAppendOutputStream() throws IOException {
+            return a.getAppendOutputStream();
+        }
+    }
+
+    private static class AppendableTouchableMR extends TouchableMR
+        implements Appendable {
+        private final Appendable a;
+
+        protected AppendableTouchableMR(Resource r) {
+            super(r);
+            if (!(r instanceof Appendable)) {
+                throw new IllegalArgumentException("trying to wrap something "
+                                                   + "that is not a "
+                                                   + " Appendable");
+            }
+            a = (Appendable) r;
+        }
+
+        public OutputStream getAppendOutputStream() throws IOException {
+            return a.getAppendOutputStream();
+        }
+    }
+
+    private static class AppendableTouchableFileProviderMR
+        extends TouchableFileProviderMR
+        implements Appendable {
+        private final Appendable a;
+
+        protected AppendableTouchableFileProviderMR(Resource r) {
+            super(r);
+            if (!(r instanceof Appendable)) {
+                throw new IllegalArgumentException("trying to wrap something "
+                                                   + "that is not a "
+                                                   + " Appendable");
+            }
+            a = (Appendable) r;
+        }
+
+        public OutputStream getAppendOutputStream() throws IOException {
+            return a.getAppendOutputStream();
+        }
+    }
+
+}