/*==========================================================================*\
| $Id: DocumentProvider.java,v 1.1 2010/05/11 15:52:46 aallowat Exp $
|*-------------------------------------------------------------------------*|
| Copyright (C) 2006-2008 Virginia Tech
|
| This file is part of Web-CAT.
|
| Web-CAT is free software; you can redistribute it and/or modify
| it under the terms of the GNU Affero General Public License as published
| by the Free Software Foundation; either version 3 of the License, or
| (at your option) any later version.
|
| Web-CAT 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 Affero General Public License
| along with Web-CAT; if not, see <http://www.gnu.org/licenses/>.
\*==========================================================================*/
package org.webcat.oda.designer.ognl;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.Reader;
import org.eclipse.core.resources.ResourcesPlugin;
import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.ILog;
import org.eclipse.core.runtime.IProgressMonitor;
import org.eclipse.core.runtime.IStatus;
import org.eclipse.core.runtime.Platform;
import org.eclipse.core.runtime.Status;
import org.eclipse.jface.operation.IRunnableContext;
import org.eclipse.jface.text.Document;
import org.eclipse.jface.text.IDocument;
import org.eclipse.jface.text.source.IAnnotationModel;
import org.eclipse.ui.IEditorInput;
import org.eclipse.ui.PlatformUI;
import org.eclipse.ui.texteditor.AbstractDocumentProvider;
import org.osgi.framework.Bundle;
//------------------------------------------------------------------------
/**
* TODO: real description
*
* @author Tony Allevato (Virginia Tech Computer Science)
* @version $Id: DocumentProvider.java,v 1.1 2010/05/11 15:52:46 aallowat Exp $
*/
public abstract class DocumentProvider extends AbstractDocumentProvider
{
//~ Constructor ...........................................................
// ----------------------------------------------------------
/**
* Creates a new document provider.
*/
public DocumentProvider()
{
super();
}
//~ Methods ...............................................................
// ----------------------------------------------------------
/**
* Initializes the given document with the given stream.
*
* @param document
* the document to be initialized
* @param contentStream
* the stream which delivers the document content
* @throws CoreException
* if the given stream can not be read
*
*/
protected void setDocumentContent(IDocument document,
InputStream contentStream) throws CoreException
{
setDocumentContent(document, contentStream, null);
}
// ----------------------------------------------------------
/**
* Initializes the given document with the given stream using the given
* encoding.
*
* @param document
* the document to be initialized
* @param contentStream
* the stream which delivers the document content
* @param encoding
* the character encoding for reading the given stream
* @throws CoreException
* if the given stream can not be read
*/
protected void setDocumentContent(IDocument document,
InputStream contentStream, String encoding) throws CoreException
{
Reader in = null;
try
{
if (encoding == null)
encoding = getDefaultEncoding();
in = new BufferedReader(new InputStreamReader(contentStream,
encoding), DEFAULT_FILE_SIZE);
StringBuffer buffer = new StringBuffer(DEFAULT_FILE_SIZE);
char[] readBuffer = new char[2048];
int n = in.read(readBuffer);
while (n > 0)
{
buffer.append(readBuffer, 0, n);
n = in.read(readBuffer);
}
document.set(buffer.toString());
}
catch (IOException x)
{
String message = (x.getMessage() != null ? x.getMessage() : ""); //$NON-NLS-1$
IStatus s = new Status(IStatus.ERROR, PlatformUI.PLUGIN_ID,
IStatus.OK, message, x);
throw new CoreException(s);
}
finally
{
try
{
if (in != null)
in.close();
else
contentStream.close();
}
catch (IOException x)
{
// Ignore exception.
}
}
}
// ----------------------------------------------------------
/**
* Initializes the given document from the given editor input using the
* given character encoding.
*
* @param document
* the document to be initialized
* @param editorInput
* the input from which to derive the content of the document
* @param encoding
* the character encoding used to read the editor input
* @return <code>true</code> if the document content could be set,
* <code>false</code> otherwise
* @throws CoreException
* if the given editor input cannot be accessed
*/
abstract protected boolean setDocumentContent(IDocument document,
IEditorInput editorInput) throws CoreException;
// ----------------------------------------------------------
protected IAnnotationModel createAnnotationModel(Object element)
throws CoreException
{
return null;
}
// ----------------------------------------------------------
/**
* Factory method for creating empty documents.
*
* @return the newly created document
*/
protected IDocument createEmptyDocument()
{
return new Document();
}
// ----------------------------------------------------------
protected IDocument createDocument(Object element) throws CoreException
{
if (element instanceof IEditorInput)
{
IDocument document = createEmptyDocument();
if (setDocumentContent(document, (IEditorInput) element))
{
setupDocument(element, document);
return document;
}
}
return null;
}
// ----------------------------------------------------------
/**
* Sets up the given document as it would be provided for the given element.
* The content of the document is not changed. This default implementation
* is empty. Subclasses may reimplement.
*
* @param element
* the blue-print element
* @param document
* the document to set up
*/
protected void setupDocument(Object element, IDocument document)
{
// Do nothing.
}
// ----------------------------------------------------------
protected void doSaveDocument(IProgressMonitor monitor, Object element,
IDocument document, boolean overwrite) throws CoreException
{
// Do nothing.
}
// ----------------------------------------------------------
/**
* Defines the standard procedure to handle <code>CoreExceptions</code>.
* Exceptions are written to the plug-in log.
*
* @param exception
* the exception to be logged
* @param message
* the message to be logged
*/
protected void handleCoreException(CoreException exception, String message)
{
Bundle bundle = Platform.getBundle(PlatformUI.PLUGIN_ID);
ILog log = Platform.getLog(bundle);
if (message != null)
log.log(new Status(IStatus.ERROR, PlatformUI.PLUGIN_ID, 0, message,
exception));
else
log.log(exception.getStatus());
}
// ----------------------------------------------------------
public String getDefaultEncoding()
{
return ResourcesPlugin.getEncoding();
}
// ----------------------------------------------------------
/**
* Returns the persisted encoding for the given element.
*
* @param element
* the element for which to get the persisted encoding
* @return the persisted encoding
*/
protected abstract String getPersistedEncoding(Object element);
// ----------------------------------------------------------
protected IRunnableContext getOperationRunner(IProgressMonitor monitor)
{
return null;
}
//~ Static/instance variables .............................................
/** Default file size. */
protected static final int DEFAULT_FILE_SIZE = 15 * 1024;
}