org.netbeans.api.diff.StreamSource Maven / Gradle / Ivy
The newest version!
/*
* 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.netbeans.api.diff;
import java.io.*;
import java.nio.charset.Charset;
import java.nio.charset.UnsupportedCharsetException;
import java.nio.file.Files;
import org.openide.util.io.ReaderInputStream;
import org.openide.util.Lookup;
import org.openide.util.lookup.Lookups;
import org.openide.filesystems.FileUtil;
import org.netbeans.api.queries.FileEncodingQuery;
/**
* This class provides streams and information about them to be used by diff
* and merge services.
*
* @author Martin Entlicher
*/
public abstract class StreamSource extends Object {
/**
* Get the name of the source.
*/
public abstract String getName();
/**
* Get the title of the source.
*/
public abstract String getTitle();
/**
* Get the MIME type of the source.
*/
public abstract String getMIMEType();
/**
* Hint for a diff visualizer about editability of this source. The source will only be made editable if it provides
* some editable entity in its lookup (eg. FileObject) and this method returns true and the diff visualizer supports it.
*
* @return true if this source can be editable in the diff visualizer, false otherwise
* @since 1.17
*/
public boolean isEditable() {
return false;
}
/**
* Source lookup that may define the content of this source. In case the lookup does not provide anything
* usable, createReader() is used instead. Diff engines can process these inputs:
*
* - instance of {@link org.openide.filesystems.FileObject} - in this case, the content of the source is defined
* by calling DataObject.find(fileObject).openDocument(). If the source is editable then it is
* saved back via SaveCookie.save() when the Diff component closes.
*
- instance of {@link javax.swing.text.Document} - in this case, the content of the source is defined
* by this Document and the source will NOT be editable.
*
*
* For compatibility purposes, it is still adviced to fully implement createReader() as older Diff providers may
* not use this method of obtaining the source.
*
* @return an instance of Lookup
* @since 1.17
*/
public Lookup getLookup() {
return Lookups.fixed();
}
/**
* Create a reader, that reads the source.
*/
public abstract Reader createReader() throws IOException ;
/**
* Create a writer, that writes to the source.
* @param conflicts The list of conflicts remaining in the source.
* Can be null if there are no conflicts.
* @return The writer or null, when no writer can be created.
*/
public abstract Writer createWriter(Difference[] conflicts) throws IOException ;
/**
* Close the stream source. This method, is called when this object
* will never be asked for the streams any more and thus can
* release it's resources in this method.
*/
public void close() {
}
/**
* Create the default implementation of StreamSource, that has
* just reader and no writer.
*/
public static StreamSource createSource(String name, String title, String MIMEType, Reader r) {
return new Impl(name, title, MIMEType, r);
}
/**
* Create the default implementation of StreamSource, that has
* just reader and writer from/to a file.
*/
public static StreamSource createSource(String name, String title, String MIMEType, File file) {
return new Impl(name, title, MIMEType, file);
}
/**
* Private implementation to be returned by the static methods.
*/
private static class Impl extends StreamSource {
private String name;
private String title;
private String MIMEType;
private Reader r;
private File readerSource;
private Writer w;
private File file;
private Charset encoding;
Impl(String name, String title, String MIMEType, Reader r) {
this.name = name;
this.title = title;
this.MIMEType = MIMEType;
this.r = r;
this.readerSource = null;
this.w = null;
this.file = null;
if (r instanceof InputStreamReader) {
try {
encoding = Charset.forName(((InputStreamReader) r).getEncoding());
} catch (UnsupportedCharsetException e) {
// ignore, encoding will be null
}
}
}
Impl(String name, String title, String MIMEType, File file) {
this.name = name;
this.title = title;
this.MIMEType = MIMEType;
this.readerSource = null;
this.w = null;
this.file = file;
encoding = FileEncodingQuery.getEncoding(FileUtil.toFileObject(file));
}
private File createReaderSource(Reader r) throws IOException {
File tmp = null;
tmp = FileUtil.normalizeFile(Files.createTempFile("sss", "tmp").toFile());
tmp.deleteOnExit();
tmp.createNewFile();
InputStream in = null;
OutputStream out = null;
try {
if (encoding == null) {
in = new ReaderInputStream(r);
} else {
ByteArrayOutputStream baos = new ByteArrayOutputStream();
copyStreamsCloseAll(new OutputStreamWriter(baos, encoding), r);
in = new ByteArrayInputStream(baos.toByteArray());
}
org.openide.filesystems.FileUtil.copy(in, out = new FileOutputStream(tmp));
} finally {
if (in != null) in.close();
if (out != null) out.close();
}
return tmp;
}
public String getName() {
return name;
}
public String getTitle() {
return title;
}
public String getMIMEType() {
return MIMEType;
}
public Reader createReader() throws IOException {
if (file != null) {
return new BufferedReader(new InputStreamReader(new FileInputStream(file), encoding));
} else {
synchronized (this) {
if (r != null) {
readerSource = createReaderSource(r);
r = null;
}
}
if (encoding == null) {
return new BufferedReader(new FileReader(readerSource));
} else {
return new BufferedReader(new InputStreamReader(new FileInputStream(readerSource), encoding));
}
}
}
public Writer createWriter(Difference[] conflicts) throws IOException {
if (conflicts != null && conflicts.length > 0) return null;
if (file != null) {
if (encoding == null) {
return new BufferedWriter(new FileWriter(file));
} else {
return new BufferedWriter(new OutputStreamWriter(new FileOutputStream(file), encoding));
}
} else return w;
}
}
private static void copyStreamsCloseAll(Writer writer, Reader reader) throws IOException {
char [] buffer = new char[4096];
int n;
while ((n = reader.read(buffer)) != -1) {
writer.write(buffer, 0, n);
}
writer.close();
reader.close();
}
}
© 2015 - 2025 Weber Informatics LLC | Privacy Policy