content: /*
   * Copyright (c) 2012, 2016, 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.  Oracle designates this
   * particular file as subject to the "Classpath" exception as provided
   * by Oracle in the LICENSE file that accompanied this code.
   *
   * 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 openjdk.tools.sjavac.comp;
  
  import openjdk.tools.sjavac.Log;
  
  import java.io.*;
  import jdkx.tools.JavaFileObject;
  
  /**
   * The SmartWriter will cache the written data and when the writer is closed,
   * then it will compare the cached data with the old_content string.
   * If different, then it will write all the new content to the file.
   * If not, the file is not touched.
   *
   *  <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>
   */
  public class SmartWriter extends Writer {
  
      String name;
      JavaFileObject file;
      String oldContent;
      StringWriter newContent = new StringWriter();
      boolean closed;
  
      public SmartWriter(JavaFileObject f, String s, String n) {
          name = n;
          file = f;
          oldContent = s;
          newContent = new StringWriter();
          closed = false;
      }
  
      public void write(char[] chars, int i, int i1) {
          newContent.write(chars, i, i1);
      }
  
      public void close() throws IOException {
          if (closed) return;
          closed = true;
          String s = newContent.toString();
          if (!oldContent.equals(s)) {
              int p = file.getName().lastIndexOf(File.separatorChar);
              try (Writer writer = file.openWriter()) {
                  writer.write(s);
              }
              Log.debug("Writing " + file.getName().substring(p + 1));
          }
      }
  
      public void flush() throws IOException {
      }
  }
  