FileResponse.java :  » J2EE » wicket-1.4 » org » apache » wicket » response » Java Open Source

/*
 * 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.wicket.response;

import java.io.BufferedWriter;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.FileWriter;
import java.io.IOException;
import java.io.OutputStream;
import java.io.PrintWriter;

import org.apache.wicket.Response;
import org.apache.wicket.WicketRuntimeException;
import org.apache.wicket.util.file.File;


/**
 * A Response implementation that writes to a file.
 * 
 * @author Jonathan Locke
 */
public final class FileResponse extends Response
{
  /** The file to write to */
  private final File file;

  /** Output stream to write to */
  private OutputStream out;

  /** Output PrintWriter to write to */
  private PrintWriter printWriter;

  /**
   * Constructor
   * 
   * @param file
   *            The file to write to
   */
  public FileResponse(final File file)
  {
    this.file = file;
  }

  /**
   * @see org.apache.wicket.Response#close()
   */
  @Override
  public void close()
  {
    if (printWriter != null)
    {
      printWriter.close();
      printWriter = null;
    }
    if (out != null)
    {
      try
      {
        out.close();
        out = null;
      }
      catch (IOException e)
      {
        throw new WicketRuntimeException("Unable to close to file " + file, e);
      }
    }
  }

  /**
   * @see org.apache.wicket.Response#getOutputStream()
   */
  @Override
  public OutputStream getOutputStream()
  {
    try
    {
      if (out == null)
      {
        out = new FileOutputStream(file);
      }
      return out;
    }
    catch (FileNotFoundException e)
    {
      throw new WicketRuntimeException("Unable to get output stream to file " + file, e);
    }
  }

  /**
   * @see org.apache.wicket.Response#write(CharSequence)
   */
  @Override
  public void write(final CharSequence string)
  {
    try
    {
      getPrintWriter().print(string);
    }
    catch (IOException e)
    {
      throw new WicketRuntimeException("Unable to write to file " + file, e);
    }
  }

  private PrintWriter getPrintWriter() throws IOException
  {
    if (printWriter == null)
    {
      printWriter = new PrintWriter(new BufferedWriter(new FileWriter(file)));
    }
    return printWriter;
  }
}