FileObject.java

/* FileObject.java --
   Copyright (C) 2008  Free Software Foundation, Inc.

This file is part of GNU Classpath.

GNU Classpath is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.

GNU Classpath 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 for more details.

You should have received a copy of the GNU General Public License
along with GNU Classpath; see the file COPYING.  If not, write to the
Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
02110-1301 USA.

Linking this library statically or dynamically with other modules is
making a combined work based on this library.  Thus, the terms and
conditions of the GNU General Public License cover the whole
combination.

As a special exception, the copyright holders of this library give you
permission to link this library with independent modules to produce an
executable, regardless of the license terms of these independent
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terms of your choice, provided that you also meet, for each linked
independent module, the terms and conditions of the license of that
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this exception to your version of the library, but you are not
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package javax.tools;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.Reader;
import java.io.Writer;
import java.net.URI;

/**
 * Abstraction for all kinds of file objects used by tools, e.g. regular files,
 * memory cache, or database data.
 *
 * @author Roman Kennke (roman@kennke.org)
 *
 * @since 1.6
 */
public interface FileObject
{

  /**
   * Returns a URI that represents this file object.
   *
   * @return a URI that represents this file object
   */
  URI toUri();

  /**
   * Returns a name for this file object. The exact name is implementation
   * dependent.
   *
   * @return a name for this file object
   */
  String getName();

  /**
   * Opens this file for reading and returns an input stream.
   *
   * @return an input stream to read this file object
   *
   * @throws IOException if an I/O error occured
   * @throws IllegalStateException if this file was opened for writing and
   *         does not support reading
   * @throws UnsupportedOperationException if this kind of file does not allow
   *         byte reading
   */
  InputStream openInputStream() throws IOException;

  /**
   * Opens this file for writing and returns an output stream.
   *
   * @return an output stream for writing this file object
   *
   * @throws IOException if an I/O error occurs
   * @throws IllegalStateException if this file was opened for reading and
   *         does not support writing
   * @throws UnsupportedOperationException if this kind of file does not allow
   *         byte writing
   */
  OutputStream openOutputStream() throws IOException;

  /**
   * Opens this file for reading and returns a reader.
   *
   * @param ignoreEncodingErrors <code>true</code> when encoding errors should be ignored
   *                             <code>false</code> otherwise
   * @return a reader for reading this file object
   *
   * @throws IOException if an I/O error occurs
   * @throws IllegalStateException if this file was opened for writing and
   *         does not support reading
   * @throws UnsupportedOperationException if this kind of file does not allow
   *         character reading
   */
  Reader openReader(boolean ignoreEncodingErrors) throws IOException;

  /**
   * Returns the character content of the file, if available. Any byte
   * that cannot be decoded will be replaced by the default replacement
   * character. A diagnostic may be reported, unless
   * <code>ignoreEncodingErrors</code> is <code>true</code>.
   * 
   * @param ignoreEncodingErrors <code>true</code> when encoding errors should be ignored
   *                             <code>false</code> otherwise
   * @return the character content, or <code>null</code> if not available
   *
   * @throws IOException if an I/O error occurs
   */
  CharSequence getCharContent(boolean ignoreEncodingErrors) throws IOException;

  /**
   * Opens this file for writer and returns a writer.
   *
   * @return a writer for writing this file object
   *
   * @throws IOException if an I/O error occurs
   * @throws IllegalStateException if this file was opened for reading and
   *         does not support writing
   * @throws UnsupportedOperationException if this kind of file does not allow
   *         character writing
   */
  Writer openWriter() throws IOException;

  /**
   * Returns the time when the file was last modified. The time is measured
   * like in <code>System.currentTimeMillis()</code>.
   *
   * @return the time when the file was last modified
   */
  long getLastModified();

  /**
   * Deletes this file object. In case of errors this returns
   * <code>false</code>.
   *
   * @return <code>true</code> when the file deletion was successful,
   *         <code>false</code> otherwise
   */
  boolean delete();
}