/*
* 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.uima.caseditor.core.model;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.InputStream;
import java.lang.ref.SoftReference;
import org.apache.uima.cas.CAS;
import org.apache.uima.caseditor.CasEditorPlugin;
import org.apache.uima.caseditor.core.model.delta.INlpElementDelta;
import org.apache.uima.caseditor.editor.DocumentFormat;
import org.apache.uima.caseditor.editor.DocumentUimaImpl;
import org.apache.uima.caseditor.editor.ICasDocument;
import org.eclipse.core.resources.IFile;
import org.eclipse.core.resources.IResource;
import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.IAdaptable;
import org.eclipse.core.runtime.IStatus;
import org.eclipse.core.runtime.Status;
/**
* The document element contains the uima cas document.
*/
public final class DocumentElement extends AbstractNlpElement implements IAdaptable {
private CorpusElement mParent;
private IFile mDocumentFile;
/**
* The working copy of the document. This instance is shared by everyone who wants to edit the
* document.
*/
private SoftReference<DocumentUimaImpl> mWorkingCopy = new SoftReference<DocumentUimaImpl>(null);
private boolean isSavingWorkingCopy;
/**
* Initializes a new instance.
*
* @param corpus
* @param documentFile
*/
DocumentElement(CorpusElement corpus, IFile documentFile) {
if (corpus == null || documentFile == null) {
throw new IllegalArgumentException("Parameters must not be null!");
}
mParent = corpus;
mDocumentFile = documentFile;
}
/**
* Retrieves the corresponding resource.
*/
public IFile getResource() {
return mDocumentFile;
}
/**
* Retrieves the name.
*/
public String getName() {
return mDocumentFile.getName();
}
/**
* Retrieves the parent.
*/
public INlpElement getParent() {
return mParent;
}
/**
* Retrieves the working copy.
*
* @throws CoreException
* @return the working copy
*/
public ICasDocument getDocument(boolean reload) throws CoreException {
NlpProject project = (NlpProject) mParent.getParent();
if (project.getTypesystemElement() == null) {
mWorkingCopy = null;
throw new CoreException(new Status(IStatus.ERROR, CasEditorPlugin.ID, 0,
"Typesystem not available!", null));
}
DocumentUimaImpl document = mWorkingCopy.get();
if (reload || document == null) {
InputStream in = mDocumentFile.getContents();
DocumentFormat format;
if (getResource().getFileExtension().equalsIgnoreCase("xcas")) {
format = DocumentFormat.XCAS;
} else if (getResource().getFileExtension().equalsIgnoreCase("xmi")) {
format = DocumentFormat.XMI;
} else {
throw new CoreException(new Status(IStatus.ERROR, CasEditorPlugin.ID, 0,
"Unkown file extension!", null));
}
// TODO: check if this is correct this way
CAS cas = project.getTypesystemElement().getCAS();
document = new DocumentUimaImpl(cas, in, format);
mWorkingCopy = new SoftReference<DocumentUimaImpl>(document);
}
return document;
}
/**
* Writes the document element to the file system.
*
* TODO: move it to the document, maybe the document gets not saved if the caller lost the
* reference to it, before this call
*
* @throws CoreException
*/
public void saveDocument() throws CoreException {
isSavingWorkingCopy = true;
ByteArrayOutputStream outStream = new ByteArrayOutputStream(40000);
((DocumentUimaImpl) getDocument(false)).serialize(outStream);
InputStream stream = new ByteArrayInputStream(outStream.toByteArray());
mDocumentFile.setContents(stream, true, false, null);
}
/**
* Retrieves the corresponding {@link NlpProject} instance.
*
* @return the {@link NlpProject} instance
*/
public NlpProject getNlpProject() {
return (NlpProject) getParent().getParent();
}
/**
* Not implemented.
*/
@Override
void addResource(INlpElementDelta delta, IResource resource) {
// not needed here, there are no resources
}
@Override
void changedResource(IResource resource, INlpElementDelta delta) {
// TODO: What should happen if the document is changed externally
// e.g. with a text editor ?
// if saveDocument() was called, we receive a changedResource event
// in this case do not remove a reference to the working copy, cause its in sync
if (!isSavingWorkingCopy) {
mWorkingCopy = new SoftReference<DocumentUimaImpl>(null);
} else {
isSavingWorkingCopy = false;
}
}
/**
* Not implemented.
*/
@Override
void removeResource(INlpElementDelta delta, IResource resource) {
// not needed here, there are no resources
}
/**
* Generates a hash code for the current instance.
*/
@Override
public int hashCode() {
return getName().hashCode();
}
}