org.eclipse.core.filebuffers/src/org/eclipse/core/internal/filebuffers/ResourceTextFileBuffer.java - platform/eclipse.platform.text - Git at Google

 /*******************************************************************************
  * Copyright (c) 2000, 2014 IBM Corporation and others.
  *
  * This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License 2.0
  * which accompanies this distribution, and is available at
  * https://www.eclipse.org/legal/epl-2.0/
  *
  * SPDX-License-Identifier: EPL-2.0
  *
  * Contributors:
  *     IBM Corporation - initial API and implementation
  *******************************************************************************/
 package org.eclipse.core.internal.filebuffers;

 import java.io.BufferedReader;
 import java.io.ByteArrayInputStream;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.InputStreamReader;
 import java.io.Reader;
 import java.io.SequenceInputStream;
 import java.nio.ByteBuffer;
 import java.nio.CharBuffer;
 import java.nio.charset.CharacterCodingException;
 import java.nio.charset.Charset;
 import java.nio.charset.CharsetEncoder;
 import java.nio.charset.CodingErrorAction;
 import java.nio.charset.IllegalCharsetNameException;
 import java.nio.charset.StandardCharsets;
 import java.nio.charset.UnmappableCharacterException;
 import java.nio.charset.UnsupportedCharsetException;

 import org.eclipse.osgi.util.NLS;

 import org.eclipse.core.runtime.Assert;
 import org.eclipse.core.runtime.CoreException;
 import org.eclipse.core.runtime.IProgressMonitor;
 import org.eclipse.core.runtime.IStatus;
 import org.eclipse.core.runtime.Platform;
 import org.eclipse.core.runtime.QualifiedName;
 import org.eclipse.core.runtime.Status;
 import org.eclipse.core.runtime.SubMonitor;
 import org.eclipse.core.runtime.content.IContentDescription;
 import org.eclipse.core.runtime.content.IContentType;

 import org.eclipse.core.resources.IFile;
 import org.eclipse.core.resources.IResourceStatus;

 import org.eclipse.core.filebuffers.IFileBufferStatusCodes;
 import org.eclipse.core.filebuffers.IPersistableAnnotationModel;
 import org.eclipse.core.filebuffers.ITextFileBuffer;
 import org.eclipse.core.filebuffers.manipulation.ContainerCreator;

 import org.eclipse.jface.text.BadPositionCategoryException;
 import org.eclipse.jface.text.DocumentEvent;
 import org.eclipse.jface.text.IDocument;
 import org.eclipse.jface.text.IDocumentExtension4;
 import org.eclipse.jface.text.IDocumentListener;
 import org.eclipse.jface.text.source.IAnnotationModel;


 /**
  * @since 3.0
  */
 public class ResourceTextFileBuffer extends ResourceFileBuffer implements ITextFileBuffer {

 	private class DocumentListener implements IDocumentListener {

 		@Override
 		public void documentAboutToBeChanged(DocumentEvent event) {
 			// do nothing
 		}

 		@Override
 		public void documentChanged(DocumentEvent event) {
 			if (fCanBeSaved && fSynchronizationStamp == event.getModificationStamp()) {
 				fCanBeSaved= false;
 				fManager.fireDirtyStateChanged(ResourceTextFileBuffer.this, fCanBeSaved);
 			} else if (!fCanBeSaved) {
 				fCanBeSaved= true;
 				fManager.fireDirtyStateChanged(ResourceTextFileBuffer.this, fCanBeSaved);
 			}
 		}
 	}

 	/**
 	 * Reader chunk size.
 	 */
 	static final private int READER_CHUNK_SIZE= 2048;
 	/**
 	 * Buffer size.
 	 */
 	static final private int BUFFER_SIZE= 8 * READER_CHUNK_SIZE;
 	/**
 	 * Qualified name for the encoding key.
 	 */
 	static final private QualifiedName ENCODING_KEY= new QualifiedName(FileBuffersPlugin.PLUGIN_ID, "encoding");  //$NON-NLS-1$
 	/**
 	 * Constant for representing the error status. This is considered a value object.
 	 */
 	static final private IStatus STATUS_ERROR= new Status(IStatus.ERROR, FileBuffersPlugin.PLUGIN_ID, IStatus.OK, FileBuffersMessages.FileBuffer_status_error, null);

 	/**
 	 * Constant denoting an empty set of properties
 	 * @since 3.1
 	 */
 	private static final QualifiedName[] NO_PROPERTIES= new QualifiedName[0];


 	/** The element's document */
 	protected IDocument fDocument;
 	/** The encoding used to create the document from the storage or <code>null</code> for workbench encoding. */
 	protected String fEncoding;
 	/** Internal document listener */
 	protected IDocumentListener fDocumentListener= new DocumentListener();
 	/** The element's annotation model */
 	protected IAnnotationModel fAnnotationModel;
 	/** The encoding which has explicitly been set on the file. */
 	private String fExplicitEncoding;
 	/** The BOM that needs to get written. */
 	private byte[] fBOM;
 	/**
 	 * Lock for lazy creation of annotation model.
 	 * @since 3.2
 	 */
 	private final Object fAnnotationModelCreationLock= new Object();


 	public ResourceTextFileBuffer(ResourceTextFileBufferManager manager) {
 		super(manager);
 	}

 	@Override
 	public IDocument getDocument() {
 		return fDocument;
 	}

 	@Override
 	public IAnnotationModel getAnnotationModel() {
 		synchronized (fAnnotationModelCreationLock) {
 			if (fAnnotationModel == null && !isDisconnected()) {
 				fAnnotationModel= getManager().createAnnotationModel(fFile);
 				if (fAnnotationModel != null)
 					fAnnotationModel.connect(fDocument);
 			}
 		}
 		return fAnnotationModel;
 	}

 	/**
 	 * Returns the file buffer manager.
 	 *
 	 * @return the file buffer manager
 	 * @since 3.4
 	 */
 	private ResourceTextFileBufferManager getManager() {
 		return (ResourceTextFileBufferManager)fManager;
 	}

 	@Override
 	public String getEncoding() {
 		return fEncoding;
 	}

 	@Override
 	public void setEncoding(String encoding) {
 		fEncoding= encoding;
 		fExplicitEncoding= encoding;
 		fBOM= null;
 		try {
 			fFile.setCharset(encoding, null);
 			if (encoding == null)
 				fEncoding= fFile.getCharset();
 			cacheBOM();
 		} catch (CoreException x) {
 			handleCoreException(x);
 		}
 	}

 	@Override
 	public IStatus getStatus() {
 		if (!isDisconnected()) {
 			if (fStatus != null)
 				return fStatus;
 			return (fDocument == null ? STATUS_ERROR : Status.OK_STATUS);
 		}
 		return STATUS_ERROR;
 	}

 	@Override
 	public IContentType getContentType() throws CoreException {
 		try {
 			if (isDirty()) {
 				try(Reader reader = new DocumentReader(getDocument())) {
 					IContentDescription desc= Platform.getContentTypeManager().getDescriptionFor(reader, fFile.getName(), NO_PROPERTIES);
 					if (desc != null && desc.getContentType() != null)
 						return desc.getContentType();
 				}
 			}
 			IContentDescription desc= fFile.getContentDescription();
 			if (desc != null && desc.getContentType() != null)
 				return desc.getContentType();
 			return null;
 		} catch (IOException x) {
 			throw new CoreException(new Status(IStatus.ERROR, FileBuffersPlugin.PLUGIN_ID, IStatus.OK, NLSUtility.format(FileBuffersMessages.FileBuffer_error_queryContentDescription, fFile.getFullPath().toOSString()), x));
 		}
 	}

 	@Override
 	protected void addFileBufferContentListeners() {
 		if (fDocument != null)
 			fDocument.addDocumentListener(fDocumentListener);
 	}

 	@Override
 	protected void removeFileBufferContentListeners() {
 		if (fDocument != null)
 			fDocument.removeDocumentListener(fDocumentListener);
 	}

 	@Override
 	protected void initializeFileBufferContent(IProgressMonitor monitor) throws CoreException {
 		try {
 			fEncoding= null;
 			fExplicitEncoding= null;
 			try {
 				fEncoding= fFile.getPersistentProperty(ENCODING_KEY);
 			} catch (CoreException x) {
 				// we ignore exceptions here because we support the ENCODING_KEY property only for compatibility reasons
 			}
 			if (fEncoding != null) {
 				// if we found an old encoding property, we try to migrate it to the new core.resources encoding support
 				try {
 					fExplicitEncoding= fEncoding;
 					fFile.setCharset(fEncoding, monitor);
 					// if successful delete old property
 					fFile.setPersistentProperty(ENCODING_KEY, null);
 				} catch (CoreException ex) {
 					// log problem because we could not migrate the property successfully
 					handleCoreException(ex);
 				}
 				cacheBOM();
 			} else {
 				cacheEncodingState();
 			}


 			fDocument= getManager().createEmptyDocument(fFile);
 			setDocumentContent(fDocument, fFile, fEncoding);

 		} catch (CoreException x) {
 			fDocument= getManager().createEmptyDocument(fFile);
 			fStatus= x.getStatus();
 		}
 	}

 	/**
 	 * Caches the BOM of the underlying file.
 	 *
 	 * @throws CoreException if reading of file's content description fails
 	 */
 	protected void cacheBOM() throws CoreException {
 		fBOM= null;

 		IContentDescription description= fFile.getContentDescription();
 		if (description != null)
 			fBOM= (byte[])description.getProperty(IContentDescription.BYTE_ORDER_MARK);
 	}

 	@Override
 	protected void connected() {
 		super.connected();
 		if (fAnnotationModel != null)
 			fAnnotationModel.connect(fDocument);
 	}

 	/*
 	 * @see org.eclipse.core.internal.filebuffers.ResourceFileBuffer#disconnected()
 	 */
 	@Override
 	protected void dispose() {
 		try {
 			fDocument.removePositionCategory(IDocument.DEFAULT_CATEGORY);
 		} catch (BadPositionCategoryException ex) {
 			// Category is already gone - no problem.
 		}
 		if (fAnnotationModel != null)
 			fAnnotationModel.disconnect(fDocument);
 		fDocument= null;
 		super.dispose();
 	}

 	@Override
 	protected void commitFileBufferContent(IProgressMonitor monitor, boolean overwrite) throws CoreException {
 		if (!isSynchronized() && !overwrite) {
 			String message= NLSUtility.format(FileBuffersMessages.FileBuffer_error_outOfSync, getFileStore().toURI());
 			throw new CoreException(new Status(IStatus.WARNING, FileBuffersPlugin.PLUGIN_ID, IResourceStatus.OUT_OF_SYNC_LOCAL, message, null));
 		}

 		String encoding= computeEncoding();

 		if (fBOM == IContentDescription.BOM_UTF_16LE && StandardCharsets.UTF_16.name().equals(encoding))
 			encoding= StandardCharsets.UTF_16LE.name();

 		Charset charset;
 		try {
 			charset= Charset.forName(encoding);
 		} catch (UnsupportedCharsetException ex) {
 			String message= NLSUtility.format(FileBuffersMessages.ResourceTextFileBuffer_error_unsupported_encoding_message_arg, encoding);
 			IStatus s= new Status(IStatus.ERROR, FileBuffersPlugin.PLUGIN_ID, IStatus.OK, message, ex);
 			throw new CoreException(s);
 		} catch (IllegalCharsetNameException ex) {
 			String message= NLSUtility.format(FileBuffersMessages.ResourceTextFileBuffer_error_illegal_encoding_message_arg, encoding);
 			IStatus s= new Status(IStatus.ERROR, FileBuffersPlugin.PLUGIN_ID, IStatus.OK, message, ex);
 			throw new CoreException(s);
 		}

 		CharsetEncoder encoder= charset.newEncoder();
 		encoder.onMalformedInput(CodingErrorAction.REPLACE);
 		encoder.onUnmappableCharacter(CodingErrorAction.REPORT);

 		InputStream stream;

 		try {
 			byte[] bytes;
 			ByteBuffer byteBuffer= encoder.encode(CharBuffer.wrap(fDocument.get()));
 			if (byteBuffer.hasArray())
 				bytes= byteBuffer.array();
 			else {
 				bytes= new byte[byteBuffer.limit()];
 				byteBuffer.get(bytes);
 			}
 			stream= new ByteArrayInputStream(bytes, 0, byteBuffer.limit());
 		} catch (CharacterCodingException ex) {
 			Assert.isTrue(ex instanceof UnmappableCharacterException);
 			String message= NLSUtility.format(FileBuffersMessages.ResourceTextFileBuffer_error_charset_mapping_failed_message_arg, new Object[] {encoding,getLocation().toString()});
 			IStatus s= new Status(IStatus.ERROR, FileBuffersPlugin.PLUGIN_ID, IFileBufferStatusCodes.CHARSET_MAPPING_FAILED, message, ex);
 			throw new CoreException(s);
 		}

 		/*
 		 * XXX:
 		 * This is a workaround for a corresponding bug in Java readers and writer,
 		 * see http://developer.java.sun.com/developer/bugParade/bugs/4508058.html
 		 */
 		if (fBOM == IContentDescription.BOM_UTF_8 && StandardCharsets.UTF_8.name().equals(encoding))
 			stream= new SequenceInputStream(new ByteArrayInputStream(IContentDescription.BOM_UTF_8), stream);

 		if (fBOM == IContentDescription.BOM_UTF_16LE && StandardCharsets.UTF_16LE.name().equals(encoding))
 			stream= new SequenceInputStream(new ByteArrayInputStream(IContentDescription.BOM_UTF_16LE), stream);

 		if (fFile.exists()) {

 			// here the file synchronizer should actually be removed and afterwards added again. However,
 			// we are already inside an operation, so the delta is sent AFTER we have added the listener
 			fFile.setContents(stream, overwrite, true, monitor);
 			// set synchronization stamp to know whether the file synchronizer must become active

 			if (fDocument instanceof IDocumentExtension4) {
 				fSynchronizationStamp= ((IDocumentExtension4)fDocument).getModificationStamp();
 				fFile.revertModificationStamp(fSynchronizationStamp);
 			} else
 				fSynchronizationStamp= fFile.getModificationStamp();

 			if (fAnnotationModel instanceof IPersistableAnnotationModel) {
 				IPersistableAnnotationModel persistableModel= (IPersistableAnnotationModel) fAnnotationModel;
 				persistableModel.commit(fDocument);
 			}

 		} else {
 			SubMonitor subMonitor= SubMonitor.convert(monitor, FileBuffersMessages.ResourceTextFileBuffer_task_saving, 2);
 			ContainerCreator creator= new ContainerCreator(fFile.getWorkspace(), fFile.getParent().getFullPath());
 			creator.createContainer(subMonitor.split(1));

 			fFile.create(stream, false, subMonitor.split(1));


 			// set synchronization stamp to know whether the file synchronizer must become active
 			fSynchronizationStamp= fFile.getModificationStamp();

 			subMonitor.split(1);
 			// TODO commit persistable annotation model
 		}

 	}

 	private String computeEncoding() {
 		// User-defined encoding has first priority
 		if (fExplicitEncoding != null)
 			return fExplicitEncoding;

 		// Probe content

 		try(Reader reader= new DocumentReader(fDocument)) {
 			QualifiedName[] options= new QualifiedName[] { IContentDescription.CHARSET, IContentDescription.BYTE_ORDER_MARK };
 			IContentDescription description= Platform.getContentTypeManager().getDescriptionFor(reader, fFile.getName(), options);
 			if (description != null) {
 				String encoding= description.getCharset();
 				if (encoding != null)
 					return encoding;
 			}
 		} catch (IOException ex) {
 			// try next strategy
 		}

 		// Use file's encoding if the file has a BOM
 		if (fBOM != null)
 			return fEncoding;

 		// Use parent chain
 		try {
 			return fFile.getParent().getDefaultCharset();
 		} catch (CoreException ex) {
 			// Use global default
 			return fManager.getDefaultEncoding();
 		}
 	}

 	/**
 	 * Internally caches the text resource's encoding.
 	 *
 	 * @throws CoreException if the encoding cannot be retrieved from the resource
 	 * @since 3.1
 	 */
 	protected void cacheEncodingState() throws CoreException {
 		fExplicitEncoding= fFile.getCharset(false);
 		if (fExplicitEncoding != null)
 			fEncoding= fExplicitEncoding;
 		else
 			fEncoding= fFile.getCharset();
 		cacheBOM();
 	}

 	@Override
 	protected void handleFileContentChanged(boolean revert, boolean updateModificationStamp) throws CoreException {

 		IDocument document= getManager().createEmptyDocument(fFile);
 		IStatus status= null;

 		try {
 			cacheEncodingState();
 			setDocumentContent(document, fFile, fEncoding);
 		} catch (CoreException x) {
 			status= x.getStatus();
 		}

 		String newContent= document.get();
 		boolean replaceContent= updateModificationStamp || !newContent.equals(fDocument.get());

 		if (replaceContent)
 			fManager.fireBufferContentAboutToBeReplaced(this);

 		removeFileBufferContentListeners();
 		fSynchronizationStamp= fFile.getModificationStamp();
 		if (replaceContent) {
 			if (fDocument instanceof IDocumentExtension4)
 				((IDocumentExtension4)fDocument).set(newContent, fSynchronizationStamp);
 			else
 				fDocument.set(newContent);
 		}
 		fCanBeSaved= false;
 		fStatus= status;
 		addFileBufferContentListeners();

 		if (replaceContent)
 			fManager.fireBufferContentReplaced(this);

 		if (fAnnotationModel instanceof IPersistableAnnotationModel) {
 			IPersistableAnnotationModel persistableModel= (IPersistableAnnotationModel) fAnnotationModel;
 			try {
 				if (revert)
 					persistableModel.revert(fDocument);
 				else
 					persistableModel.reinitialize(fDocument);
 			} catch (CoreException x) {
 				fStatus= x.getStatus();
 			}
 		}

 		fManager.fireDirtyStateChanged(this, fCanBeSaved);
 	}

 	/**
 	 * Initializes the given document with the given stream using the given encoding.
 	 *
 	 * @param document the document to be initialized
 	 * @param file the file which delivers the document content
 	 * @param encoding the character encoding for reading the given stream
 	 * @exception CoreException if the given stream can not be read
 	 */
 	private void setDocumentContent(IDocument document, IFile file, String encoding) throws CoreException {
 		InputStream contentStream= file.getContents();
 		Reader in= null;
 		try {

 			if (encoding == null)
 				encoding= fManager.getDefaultEncoding();

 			/*
 			 * XXX:
 			 * This is a workaround for a corresponding bug in Java readers and writer,
 			 * see http://developer.java.sun.com/developer/bugParade/bugs/4508058.html
 			 */
 			if (fBOM != null && StandardCharsets.UTF_8.name().equals(encoding)) {
 				int n= 0;
 				do {
 					int bytes= contentStream.read(new byte[IContentDescription.BOM_UTF_8.length]);
 					if (bytes == -1)
 						throw new IOException();
 					n += bytes;
 				} while (n < IContentDescription.BOM_UTF_8.length);
 			}

 			in= new BufferedReader(new InputStreamReader(contentStream, encoding), BUFFER_SIZE);
 			StringBuilder buffer= new StringBuilder(BUFFER_SIZE);
 			char[] readBuffer= new char[READER_CHUNK_SIZE];
 			int n= in.read(readBuffer);
 			try {
 				while (n > 0) {
 					buffer.append(readBuffer, 0, n);
 					n= in.read(readBuffer);
 				}
 			} catch (OutOfMemoryError e) {
 				// give the JVM a hint that it can free the big buffer right away
 				buffer= null;
 				throw new IOException(NLS.bind(FileBuffersMessages.ResourceTextFileBuffer_oom_on_file_read, file.getLocationURI()), e);
 			}

 			if (document instanceof IDocumentExtension4)
 				((IDocumentExtension4)document).set(buffer.toString(), fFile.getModificationStamp());
 			else
 				document.set(buffer.toString());

 		} catch (IOException x) {
 			String message= (x.getMessage() != null ? x.getMessage() : ""); //$NON-NLS-1$
 			IStatus s= new Status(IStatus.ERROR, FileBuffersPlugin.PLUGIN_ID, IStatus.OK, message, x);
 			throw new CoreException(s);
 		} finally {
 			try {
 				if (in != null)
 					in.close();
 				else
 					contentStream.close();
 			} catch (IOException x) {
 			}
 		}
 	}
 }
	/*******************************************************************************
	* Copyright (c) 2000, 2014 IBM Corporation and others.
	*
	* This program and the accompanying materials
	* are made available under the terms of the Eclipse Public License 2.0
	* which accompanies this distribution, and is available at
	* https://www.eclipse.org/legal/epl-2.0/
	*
	* SPDX-License-Identifier: EPL-2.0
	*
	* Contributors:
	* IBM Corporation - initial API and implementation
	*******************************************************************************/
	package org.eclipse.core.internal.filebuffers;

	import java.io.BufferedReader;
	import java.io.ByteArrayInputStream;
	import java.io.IOException;
	import java.io.InputStream;
	import java.io.InputStreamReader;
	import java.io.Reader;
	import java.io.SequenceInputStream;
	import java.nio.ByteBuffer;
	import java.nio.CharBuffer;
	import java.nio.charset.CharacterCodingException;
	import java.nio.charset.Charset;
	import java.nio.charset.CharsetEncoder;
	import java.nio.charset.CodingErrorAction;
	import java.nio.charset.IllegalCharsetNameException;
	import java.nio.charset.StandardCharsets;
	import java.nio.charset.UnmappableCharacterException;
	import java.nio.charset.UnsupportedCharsetException;

	import org.eclipse.osgi.util.NLS;

	import org.eclipse.core.runtime.Assert;
	import org.eclipse.core.runtime.CoreException;
	import org.eclipse.core.runtime.IProgressMonitor;
	import org.eclipse.core.runtime.IStatus;
	import org.eclipse.core.runtime.Platform;
	import org.eclipse.core.runtime.QualifiedName;
	import org.eclipse.core.runtime.Status;
	import org.eclipse.core.runtime.SubMonitor;
	import org.eclipse.core.runtime.content.IContentDescription;
	import org.eclipse.core.runtime.content.IContentType;

	import org.eclipse.core.resources.IFile;
	import org.eclipse.core.resources.IResourceStatus;

	import org.eclipse.core.filebuffers.IFileBufferStatusCodes;
	import org.eclipse.core.filebuffers.IPersistableAnnotationModel;
	import org.eclipse.core.filebuffers.ITextFileBuffer;
	import org.eclipse.core.filebuffers.manipulation.ContainerCreator;

	import org.eclipse.jface.text.BadPositionCategoryException;
	import org.eclipse.jface.text.DocumentEvent;
	import org.eclipse.jface.text.IDocument;
	import org.eclipse.jface.text.IDocumentExtension4;
	import org.eclipse.jface.text.IDocumentListener;
	import org.eclipse.jface.text.source.IAnnotationModel;


	/**
	* @since 3.0
	*/
	public class ResourceTextFileBuffer extends ResourceFileBuffer implements ITextFileBuffer {

	private class DocumentListener implements IDocumentListener {

	@Override
	public void documentAboutToBeChanged(DocumentEvent event) {
	// do nothing
	}

	@Override
	public void documentChanged(DocumentEvent event) {
	if (fCanBeSaved && fSynchronizationStamp == event.getModificationStamp()) {
	fCanBeSaved= false;
	fManager.fireDirtyStateChanged(ResourceTextFileBuffer.this, fCanBeSaved);
	} else if (!fCanBeSaved) {
	fCanBeSaved= true;
	fManager.fireDirtyStateChanged(ResourceTextFileBuffer.this, fCanBeSaved);
	}
	}
	}

	/**
	* Reader chunk size.
	*/
	static final private int READER_CHUNK_SIZE= 2048;
	/**
	* Buffer size.
	*/
	static final private int BUFFER_SIZE= 8 * READER_CHUNK_SIZE;
	/**
	* Qualified name for the encoding key.
	*/
	static final private QualifiedName ENCODING_KEY= new QualifiedName(FileBuffersPlugin.PLUGIN_ID, "encoding"); //$NON-NLS-1$
	/**
	* Constant for representing the error status. This is considered a value object.
	*/
	static final private IStatus STATUS_ERROR= new Status(IStatus.ERROR, FileBuffersPlugin.PLUGIN_ID, IStatus.OK, FileBuffersMessages.FileBuffer_status_error, null);

	/**
	* Constant denoting an empty set of properties
	* @since 3.1
	*/
	private static final QualifiedName[] NO_PROPERTIES= new QualifiedName[0];


	/** The element's document */
	protected IDocument fDocument;
	/** The encoding used to create the document from the storage or <code>null</code> for workbench encoding. */
	protected String fEncoding;
	/** Internal document listener */
	protected IDocumentListener fDocumentListener= new DocumentListener();
	/** The element's annotation model */
	protected IAnnotationModel fAnnotationModel;
	/** The encoding which has explicitly been set on the file. */
	private String fExplicitEncoding;
	/** The BOM that needs to get written. */
	private byte[] fBOM;
	/**
	* Lock for lazy creation of annotation model.
	* @since 3.2
	*/
	private final Object fAnnotationModelCreationLock= new Object();


	public ResourceTextFileBuffer(ResourceTextFileBufferManager manager) {
	super(manager);
	}

	@Override
	public IDocument getDocument() {
	return fDocument;
	}

	@Override
	public IAnnotationModel getAnnotationModel() {
	synchronized (fAnnotationModelCreationLock) {
	if (fAnnotationModel == null && !isDisconnected()) {
	fAnnotationModel= getManager().createAnnotationModel(fFile);
	if (fAnnotationModel != null)
	fAnnotationModel.connect(fDocument);
	}
	}
	return fAnnotationModel;
	}

	/**
	* Returns the file buffer manager.
	*
	* @return the file buffer manager
	* @since 3.4
	*/
	private ResourceTextFileBufferManager getManager() {
	return (ResourceTextFileBufferManager)fManager;
	}

	@Override
	public String getEncoding() {
	return fEncoding;
	}

	@Override
	public void setEncoding(String encoding) {
	fEncoding= encoding;
	fExplicitEncoding= encoding;
	fBOM= null;
	try {
	fFile.setCharset(encoding, null);
	if (encoding == null)
	fEncoding= fFile.getCharset();
	cacheBOM();
	} catch (CoreException x) {
	handleCoreException(x);
	}
	}

	@Override
	public IStatus getStatus() {
	if (!isDisconnected()) {
	if (fStatus != null)
	return fStatus;
	return (fDocument == null ? STATUS_ERROR : Status.OK_STATUS);
	}
	return STATUS_ERROR;
	}

	@Override
	public IContentType getContentType() throws CoreException {
	try {
	if (isDirty()) {
	try(Reader reader = new DocumentReader(getDocument())) {
	IContentDescription desc= Platform.getContentTypeManager().getDescriptionFor(reader, fFile.getName(), NO_PROPERTIES);
	if (desc != null && desc.getContentType() != null)
	return desc.getContentType();
	}
	}
	IContentDescription desc= fFile.getContentDescription();
	if (desc != null && desc.getContentType() != null)
	return desc.getContentType();
	return null;
	} catch (IOException x) {
	throw new CoreException(new Status(IStatus.ERROR, FileBuffersPlugin.PLUGIN_ID, IStatus.OK, NLSUtility.format(FileBuffersMessages.FileBuffer_error_queryContentDescription, fFile.getFullPath().toOSString()), x));
	}
	}

	@Override
	protected void addFileBufferContentListeners() {
	if (fDocument != null)
	fDocument.addDocumentListener(fDocumentListener);
	}

	@Override
	protected void removeFileBufferContentListeners() {
	if (fDocument != null)
	fDocument.removeDocumentListener(fDocumentListener);
	}

	@Override
	protected void initializeFileBufferContent(IProgressMonitor monitor) throws CoreException {
	try {
	fEncoding= null;
	fExplicitEncoding= null;
	try {
	fEncoding= fFile.getPersistentProperty(ENCODING_KEY);
	} catch (CoreException x) {
	// we ignore exceptions here because we support the ENCODING_KEY property only for compatibility reasons
	}
	if (fEncoding != null) {
	// if we found an old encoding property, we try to migrate it to the new core.resources encoding support
	try {
	fExplicitEncoding= fEncoding;
	fFile.setCharset(fEncoding, monitor);
	// if successful delete old property
	fFile.setPersistentProperty(ENCODING_KEY, null);
	} catch (CoreException ex) {
	// log problem because we could not migrate the property successfully
	handleCoreException(ex);
	}
	cacheBOM();
	} else {
	cacheEncodingState();
	}


	fDocument= getManager().createEmptyDocument(fFile);
	setDocumentContent(fDocument, fFile, fEncoding);

	} catch (CoreException x) {
	fDocument= getManager().createEmptyDocument(fFile);
	fStatus= x.getStatus();
	}
	}

	/**
	* Caches the BOM of the underlying file.
	*
	* @throws CoreException if reading of file's content description fails
	*/
	protected void cacheBOM() throws CoreException {
	fBOM= null;

	IContentDescription description= fFile.getContentDescription();
	if (description != null)
	fBOM= (byte[])description.getProperty(IContentDescription.BYTE_ORDER_MARK);
	}

	@Override
	protected void connected() {
	super.connected();
	if (fAnnotationModel != null)
	fAnnotationModel.connect(fDocument);
	}

	/*
	* @see org.eclipse.core.internal.filebuffers.ResourceFileBuffer#disconnected()
	*/
	@Override
	protected void dispose() {
	try {
	fDocument.removePositionCategory(IDocument.DEFAULT_CATEGORY);
	} catch (BadPositionCategoryException ex) {
	// Category is already gone - no problem.
	}
	if (fAnnotationModel != null)
	fAnnotationModel.disconnect(fDocument);
	fDocument= null;
	super.dispose();
	}

	@Override
	protected void commitFileBufferContent(IProgressMonitor monitor, boolean overwrite) throws CoreException {
	if (!isSynchronized() && !overwrite) {
	String message= NLSUtility.format(FileBuffersMessages.FileBuffer_error_outOfSync, getFileStore().toURI());
	throw new CoreException(new Status(IStatus.WARNING, FileBuffersPlugin.PLUGIN_ID, IResourceStatus.OUT_OF_SYNC_LOCAL, message, null));
	}

	String encoding= computeEncoding();

	if (fBOM == IContentDescription.BOM_UTF_16LE && StandardCharsets.UTF_16.name().equals(encoding))
	encoding= StandardCharsets.UTF_16LE.name();

	Charset charset;
	try {
	charset= Charset.forName(encoding);
	} catch (UnsupportedCharsetException ex) {
	String message= NLSUtility.format(FileBuffersMessages.ResourceTextFileBuffer_error_unsupported_encoding_message_arg, encoding);
	IStatus s= new Status(IStatus.ERROR, FileBuffersPlugin.PLUGIN_ID, IStatus.OK, message, ex);
	throw new CoreException(s);
	} catch (IllegalCharsetNameException ex) {
	String message= NLSUtility.format(FileBuffersMessages.ResourceTextFileBuffer_error_illegal_encoding_message_arg, encoding);
	IStatus s= new Status(IStatus.ERROR, FileBuffersPlugin.PLUGIN_ID, IStatus.OK, message, ex);
	throw new CoreException(s);
	}

	CharsetEncoder encoder= charset.newEncoder();
	encoder.onMalformedInput(CodingErrorAction.REPLACE);
	encoder.onUnmappableCharacter(CodingErrorAction.REPORT);

	InputStream stream;

	try {
	byte[] bytes;
	ByteBuffer byteBuffer= encoder.encode(CharBuffer.wrap(fDocument.get()));
	if (byteBuffer.hasArray())
	bytes= byteBuffer.array();
	else {
	bytes= new byte[byteBuffer.limit()];
	byteBuffer.get(bytes);
	}
	stream= new ByteArrayInputStream(bytes, 0, byteBuffer.limit());
	} catch (CharacterCodingException ex) {
	Assert.isTrue(ex instanceof UnmappableCharacterException);
	String message= NLSUtility.format(FileBuffersMessages.ResourceTextFileBuffer_error_charset_mapping_failed_message_arg, new Object[] {encoding,getLocation().toString()});
	IStatus s= new Status(IStatus.ERROR, FileBuffersPlugin.PLUGIN_ID, IFileBufferStatusCodes.CHARSET_MAPPING_FAILED, message, ex);
	throw new CoreException(s);
	}

	/*
	* XXX:
	* This is a workaround for a corresponding bug in Java readers and writer,
	* see http://developer.java.sun.com/developer/bugParade/bugs/4508058.html
	*/
	if (fBOM == IContentDescription.BOM_UTF_8 && StandardCharsets.UTF_8.name().equals(encoding))
	stream= new SequenceInputStream(new ByteArrayInputStream(IContentDescription.BOM_UTF_8), stream);

	if (fBOM == IContentDescription.BOM_UTF_16LE && StandardCharsets.UTF_16LE.name().equals(encoding))
	stream= new SequenceInputStream(new ByteArrayInputStream(IContentDescription.BOM_UTF_16LE), stream);

	if (fFile.exists()) {

	// here the file synchronizer should actually be removed and afterwards added again. However,
	// we are already inside an operation, so the delta is sent AFTER we have added the listener
	fFile.setContents(stream, overwrite, true, monitor);
	// set synchronization stamp to know whether the file synchronizer must become active

	if (fDocument instanceof IDocumentExtension4) {
	fSynchronizationStamp= ((IDocumentExtension4)fDocument).getModificationStamp();
	fFile.revertModificationStamp(fSynchronizationStamp);
	} else
	fSynchronizationStamp= fFile.getModificationStamp();

	if (fAnnotationModel instanceof IPersistableAnnotationModel) {
	IPersistableAnnotationModel persistableModel= (IPersistableAnnotationModel) fAnnotationModel;
	persistableModel.commit(fDocument);
	}

	} else {
	SubMonitor subMonitor= SubMonitor.convert(monitor, FileBuffersMessages.ResourceTextFileBuffer_task_saving, 2);
	ContainerCreator creator= new ContainerCreator(fFile.getWorkspace(), fFile.getParent().getFullPath());
	creator.createContainer(subMonitor.split(1));

	fFile.create(stream, false, subMonitor.split(1));


	// set synchronization stamp to know whether the file synchronizer must become active
	fSynchronizationStamp= fFile.getModificationStamp();

	subMonitor.split(1);
	// TODO commit persistable annotation model
	}

	}

	private String computeEncoding() {
	// User-defined encoding has first priority
	if (fExplicitEncoding != null)
	return fExplicitEncoding;

	// Probe content

	try(Reader reader= new DocumentReader(fDocument)) {
	QualifiedName[] options= new QualifiedName[] { IContentDescription.CHARSET, IContentDescription.BYTE_ORDER_MARK };
	IContentDescription description= Platform.getContentTypeManager().getDescriptionFor(reader, fFile.getName(), options);
	if (description != null) {
	String encoding= description.getCharset();
	if (encoding != null)
	return encoding;
	}
	} catch (IOException ex) {
	// try next strategy
	}

	// Use file's encoding if the file has a BOM
	if (fBOM != null)
	return fEncoding;

	// Use parent chain
	try {
	return fFile.getParent().getDefaultCharset();
	} catch (CoreException ex) {
	// Use global default
	return fManager.getDefaultEncoding();
	}
	}

	/**
	* Internally caches the text resource's encoding.
	*
	* @throws CoreException if the encoding cannot be retrieved from the resource
	* @since 3.1
	*/
	protected void cacheEncodingState() throws CoreException {
	fExplicitEncoding= fFile.getCharset(false);
	if (fExplicitEncoding != null)
	fEncoding= fExplicitEncoding;
	else
	fEncoding= fFile.getCharset();
	cacheBOM();
	}

	@Override
	protected void handleFileContentChanged(boolean revert, boolean updateModificationStamp) throws CoreException {

	IDocument document= getManager().createEmptyDocument(fFile);
	IStatus status= null;

	try {
	cacheEncodingState();
	setDocumentContent(document, fFile, fEncoding);
	} catch (CoreException x) {
	status= x.getStatus();
	}

	String newContent= document.get();
	boolean replaceContent= updateModificationStamp \|\| !newContent.equals(fDocument.get());

	if (replaceContent)
	fManager.fireBufferContentAboutToBeReplaced(this);

	removeFileBufferContentListeners();
	fSynchronizationStamp= fFile.getModificationStamp();
	if (replaceContent) {
	if (fDocument instanceof IDocumentExtension4)
	((IDocumentExtension4)fDocument).set(newContent, fSynchronizationStamp);
	else
	fDocument.set(newContent);
	}
	fCanBeSaved= false;
	fStatus= status;
	addFileBufferContentListeners();

	if (replaceContent)
	fManager.fireBufferContentReplaced(this);

	if (fAnnotationModel instanceof IPersistableAnnotationModel) {
	IPersistableAnnotationModel persistableModel= (IPersistableAnnotationModel) fAnnotationModel;
	try {
	if (revert)
	persistableModel.revert(fDocument);
	else
	persistableModel.reinitialize(fDocument);
	} catch (CoreException x) {
	fStatus= x.getStatus();
	}
	}

	fManager.fireDirtyStateChanged(this, fCanBeSaved);
	}

	/**
	* Initializes the given document with the given stream using the given encoding.
	*
	* @param document the document to be initialized
	* @param file the file which delivers the document content
	* @param encoding the character encoding for reading the given stream
	* @exception CoreException if the given stream can not be read
	*/
	private void setDocumentContent(IDocument document, IFile file, String encoding) throws CoreException {
	InputStream contentStream= file.getContents();
	Reader in= null;
	try {

	if (encoding == null)
	encoding= fManager.getDefaultEncoding();

	/*
	* XXX:
	* This is a workaround for a corresponding bug in Java readers and writer,
	* see http://developer.java.sun.com/developer/bugParade/bugs/4508058.html
	*/
	if (fBOM != null && StandardCharsets.UTF_8.name().equals(encoding)) {
	int n= 0;
	do {
	int bytes= contentStream.read(new byte[IContentDescription.BOM_UTF_8.length]);
	if (bytes == -1)
	throw new IOException();
	n += bytes;
	} while (n < IContentDescription.BOM_UTF_8.length);
	}

	in= new BufferedReader(new InputStreamReader(contentStream, encoding), BUFFER_SIZE);
	StringBuilder buffer= new StringBuilder(BUFFER_SIZE);
	char[] readBuffer= new char[READER_CHUNK_SIZE];
	int n= in.read(readBuffer);
	try {
	while (n > 0) {
	buffer.append(readBuffer, 0, n);
	n= in.read(readBuffer);
	}
	} catch (OutOfMemoryError e) {
	// give the JVM a hint that it can free the big buffer right away
	buffer= null;
	throw new IOException(NLS.bind(FileBuffersMessages.ResourceTextFileBuffer_oom_on_file_read, file.getLocationURI()), e);
	}

	if (document instanceof IDocumentExtension4)
	((IDocumentExtension4)document).set(buffer.toString(), fFile.getModificationStamp());
	else
	document.set(buffer.toString());

	} catch (IOException x) {
	String message= (x.getMessage() != null ? x.getMessage() : ""); //$NON-NLS-1$
	IStatus s= new Status(IStatus.ERROR, FileBuffersPlugin.PLUGIN_ID, IStatus.OK, message, x);
	throw new CoreException(s);
	} finally {
	try {
	if (in != null)
	in.close();
	else
	contentStream.close();
	} catch (IOException x) {
	}
	}
	}
	}