Mercurial > jdk8-mips64-public > langtools / file revision

 /*

  * Copyright (c) 2005, 2006, 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.

  */

 package evalexpr;

 import java.io.ByteArrayOutputStream;

 import java.io.FilterOutputStream;

 import java.io.IOException;

 import java.io.InputStream;

 import java.io.OutputStream;

 import java.io.Reader;

 import java.io.StringReader;

 import java.net.URI;

 import java.net.URISyntaxException;

 import java.nio.CharBuffer;

 import java.util.HashMap;

 import java.util.Map;

 import javax.tools.*;

 import javax.tools.JavaFileObject.Kind;

 /**

  * A file manager for compiling strings to byte arrays.

  * This file manager delegates to another file manager

  * to lookup classes on boot class path.

  *

  * <p><b>This is NOT part of any supported API.

  * If you write code that depends on this, you do so at your own

  * risk.  This code and its internal interfaces are subject to change

  * or deletion without notice.</b></p>

  * @author Peter von der Ahé

  */

 public final class MemoryFileManager extends ForwardingJavaFileManager {

     /**

      * Maps binary class names to class files stored as byte arrays.

      */

     private Map<String, byte[]> classes;

     /**

      * Creates a JavaFileObject representing the given compilation unit.

      * @param name a name representing this source code, for example, the name of a class

      * @param code a compilation unit (source code for a Java program)

      * @return a JavaFileObject represtenting the given compilation unit

      */

     public static JavaFileObject makeSource(String name, String code) {

         return new JavaSourceFromString(name, code);

     }

     /**

      * Construct a memory file manager which delegates to the specified

      * file manager for unknown sources.

      * @param fileManager a file manager used to look up class files on class path, etc.

      */

     public MemoryFileManager(JavaFileManager fileManager) {

         super(fileManager);

         classes = new HashMap<String, byte[]>();

     }

     /**

      * Get a class loader which first search the classes stored

      * by this file mananger.

      * @return a class loader for compiled files

      */

     @Override

     public ClassLoader getClassLoader(Location location) {

         return new ByteArrayClassLoader(classes);

     }

     @Override

     public JavaFileObject getJavaFileForOutput(Location location,

                                                String name,

                                                Kind kind,

                                                FileObject originatingSource)

         throws UnsupportedOperationException

     {

         if (originatingSource instanceof JavaSourceFromString) {

             return new JavaClassInArray(name);

         } else {

             throw new UnsupportedOperationException();

         }

     }

     protected static URI uriFromString(String uri) {

         try {

             return new URI(uri);

         } catch (URISyntaxException e) {

             throw new IllegalArgumentException(e);

         }

     }

     /**

      * A file object representing a Java class file stored in a byte array.

      */

     private class JavaClassInArray extends SimpleJavaFileObject {

         private String name;

         /**

          * Constructs a JavaClassInArray object.

          * @param name binary name of the class to be stored in this file object

          */

         JavaClassInArray(String name) {

             super(uriFromString("mfm:///" + name.replace('.','/') + Kind.CLASS.extension),

                   Kind.CLASS);

             this.name = name;

         }

         public OutputStream openOutputStream() {

             return new FilterOutputStream(new ByteArrayOutputStream()) {

                 public void close() throws IOException {

                     out.close();

                     ByteArrayOutputStream bos = (ByteArrayOutputStream)out;

                     classes.put(name, bos.toByteArray());

                     System.out.println("compiled " + name);

                 }

             };

         }

     }

     /**

      * A file object used to represent source coming from a string.

      */

     private static class JavaSourceFromString extends SimpleJavaFileObject {

         /**

          * The source code of this "file".

          */

         final String code;

         /**

          * Constructs a new JavaSourceFromString.

          * @param name the name of the compilation unit represented by this file object

          * @param code the source code for the compilation unit represented by this file object

          */

         JavaSourceFromString(String name, String code) {

             super(uriFromString("mfm:///" + name.replace('.','/') + Kind.SOURCE.extension),

                   Kind.SOURCE);

             this.code = code;

         }

         @Override

         public CharSequence getCharContent(boolean ignoreEncodingErrors) {

             return code;

         }

     }

 }