/*
* This program is free software; you can redistribute it and/or modify it under the
* terms of the GNU Lesser General Public License, version 2.1 as published by the Free Software
* Foundation.
*
* You should have received a copy of the GNU Lesser General Public License along with this
* program; if not, you can obtain a copy at http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html
* or from the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*
* This program 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 Lesser General Public License for more details.
*
* Copyright (c) 2006 - 2013 Pentaho Corporation and Contributors. All rights reserved.
*/
package org.pentaho.reporting.libraries.repository;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
/**
* A content item holds the actual content. On a file system, this would be a file. Whether reading and writing the same
* content item at the same time is allowed is implementation specific.
*
* @author Thomas Morgner
*/
public interface ContentItem extends ContentEntity {
/**
* Returns the mime type for the content entity. If the repository does not store mimetypes, this call usually uses
* the repositories MimeRegistry to resolve the mimetype.
*
* @return the mime type.
* @throws ContentIOException if an error occured.
*/
public String getMimeType() throws ContentIOException;
/**
* Tries to open and return a output stream for writing into the content item. This call will fail if the item is not
* writeable. Whether opening multiple output streams at the same time is possible is implementation dependent, but it
* is generally not recommended to try this.
* <p/>
* Having both an input and output stream open at the same time is not guaranteed to work. Generally if you need to
* append data, first open the inputstream and copy the content to a temporary location and then write the content
* along with the appended content to the new output stream.
*
* @return the output stream for writing the item.
* @throws ContentIOException if an repository related error prevents the creation of the output stream.
* @throws IOException if an IO error occurs.
*/
public OutputStream getOutputStream() throws ContentIOException, IOException;
/**
* Tries to open and return a input stream for reading from the content item. This call will fail if the item is not
* readable. Whether opening multiple input streams at the same time is possible is implementation dependent.
* <p/>
* Having both an input and output stream open at the same time is not guaranteed to work. Generally if you need to
* append data, first open the inputstream and copy the content to a temporary location and then write the content
* along with the appended content to the new output stream.
*
* @return the input stream for reading from the item.
* @throws ContentIOException if an repository related error prevents the creation of the input stream.
* @throws IOException if an IO error occurs.
*/
public InputStream getInputStream()
throws ContentIOException, IOException;
/**
* Checks, whether the content item is readable. A content item that is not readable will never return a valid
* inputstream and any call to getInputStream is bound to fail.
*
* @return true, if the content item is readable, false otherwise.
*/
public boolean isReadable();
/**
* Checks, whether the content item is writable. A content item that is not writable will never return a valid
* outputstream and any call to getOutputStream is bound to fail.
*
* @return true, if the content item is writeable, false otherwise.
*/
public boolean isWriteable();
}