diff -r 13354e1abba7 -r 3640b60bd0f6 test/tools/javac/diags/FileManager.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/tools/javac/diags/FileManager.java	Thu Jul 22 11:02:54 2010 -0700
@@ -0,0 +1,191 @@
+/*
+ * Copyright (c) 2010, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+import java.io.File;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.io.Reader;
+import java.io.Writer;
+import java.net.URI;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+import java.util.regex.Pattern;
+import javax.lang.model.element.Modifier;
+import javax.lang.model.element.NestingKind;
+import javax.tools.JavaFileManager.Location;
+import javax.tools.JavaFileObject;
+import javax.tools.StandardJavaFileManager;
+
+import com.sun.tools.javac.api.WrappingJavaFileManager;
+
+/**
+ * A JavaFileManager that can throw IOException on attempting to read or write
+ * selected files that match a regular expression.
+ */
+public class FileManager
+        extends WrappingJavaFileManager<StandardJavaFileManager>
+        implements StandardJavaFileManager {
+    private static final String CANT_READ = "cantRead:";
+    private static final String CANT_WRITE = "cantWrite:";
+
+    private Pattern cantRead;
+    private Pattern cantWrite;
+
+    public FileManager(StandardJavaFileManager fm, List<String> opts) {
+        super(fm);
+        for (String opt: opts) {
+            if (opt.startsWith(CANT_READ))
+                cantRead = Pattern.compile(opt.substring(CANT_READ.length()));
+            else if (opt.startsWith(CANT_WRITE))
+                cantWrite = Pattern.compile(opt.substring(CANT_WRITE.length()));
+            else
+                throw new IllegalArgumentException(opt);
+        }
+    }
+
+    @Override
+    protected JavaFileObject wrap(JavaFileObject fo) {
+        return new WrappedFileObject(fo);
+    }
+
+    @Override
+    protected JavaFileObject unwrap(JavaFileObject fo) {
+        if (fo instanceof WrappedFileObject)
+            return ((WrappedFileObject) fo).delegate;
+        else
+            return fo;
+    }
+
+    public Iterable<? extends JavaFileObject> getJavaFileObjectsFromFiles(Iterable<? extends File> files) {
+        return wrap2(fileManager.getJavaFileObjectsFromFiles(files));
+    }
+
+    public Iterable<? extends JavaFileObject> getJavaFileObjects(File... files) {
+        return wrap2(fileManager.getJavaFileObjects(files));
+    }
+
+    public Iterable<? extends JavaFileObject> getJavaFileObjectsFromStrings(Iterable<String> names) {
+        return wrap2(fileManager.getJavaFileObjectsFromStrings(names));
+    }
+
+    public Iterable<? extends JavaFileObject> getJavaFileObjects(String... names) {
+        return wrap2(fileManager.getJavaFileObjects(names));
+    }
+
+    /* This method is regrettably necessary because WrappingJavaFileManager.wrap takes
+     *          Iterable<JavaFileObject> fileObjects
+     * instead of
+     *          Iterable<? extends JavaFileObject> fileObjects
+     */
+    protected Iterable<JavaFileObject> wrap2(Iterable<? extends JavaFileObject> fileObjects) {
+        List<JavaFileObject> mapped = new ArrayList<JavaFileObject>();
+        for (JavaFileObject fileObject : fileObjects)
+            mapped.add(wrap(fileObject));
+        return Collections.unmodifiableList(mapped);
+    }
+
+    public void setLocation(Location location, Iterable<? extends File> path) throws IOException {
+        fileManager.setLocation(location, path);
+    }
+
+    public Iterable<? extends File> getLocation(Location location) {
+        return fileManager.getLocation(location);
+    }
+
+    class WrappedFileObject implements JavaFileObject {
+        WrappedFileObject(JavaFileObject fileObject) {
+            delegate = fileObject;
+        }
+
+        public Kind getKind() {
+            return delegate.getKind();
+        }
+
+        public boolean isNameCompatible(String simpleName, Kind kind) {
+            return delegate.isNameCompatible(simpleName, kind);
+        }
+
+        public NestingKind getNestingKind() {
+            return delegate.getNestingKind();
+        }
+
+        public Modifier getAccessLevel() {
+            return delegate.getAccessLevel();
+        }
+
+        public URI toUri() {
+            return delegate.toUri();
+        }
+
+        public String getName() {
+            return delegate.getName();
+        }
+
+        public InputStream openInputStream() throws IOException {
+            checkRead();
+            return delegate.openInputStream();
+        }
+
+        public OutputStream openOutputStream() throws IOException {
+            checkWrite();
+            return delegate.openOutputStream();
+        }
+
+        public Reader openReader(boolean ignoreEncodingErrors) throws IOException {
+            checkRead();
+            return delegate.openReader(ignoreEncodingErrors);
+        }
+
+        public CharSequence getCharContent(boolean ignoreEncodingErrors) throws IOException {
+            checkRead();
+            return delegate.getCharContent(ignoreEncodingErrors);
+        }
+
+        public Writer openWriter() throws IOException {
+            checkWrite();
+            return delegate.openWriter();
+        }
+
+        public long getLastModified() {
+            return delegate.getLastModified();
+        }
+
+        public boolean delete() {
+            return delegate.delete();
+        }
+
+        void checkRead() throws IOException {
+            if (cantRead != null && cantRead.matcher(getName()).matches())
+                throw new IOException("FileManager: Can't read");
+        }
+
+        void checkWrite() throws IOException {
+            if (cantWrite != null && cantWrite.matcher(getName()).matches())
+                throw new IOException("FileManager: Can't write");
+        }
+
+        JavaFileObject delegate;
+    }
+}