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////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// Copyright (c) 2013 Saxonica Limited.
// This Source Code Form is subject to the terms of the Mozilla Public License, v. 2.0.
// If a copy of the MPL was not distributed with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
// This Source Code Form is "Incompatible With Secondary Licenses", as defined by the Mozilla Public License, v. 2.0.
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
package net.sf.saxon.serialize;
import net.sf.saxon.Configuration;
import net.sf.saxon.event.PipelineConfiguration;
import net.sf.saxon.event.Receiver;
import net.sf.saxon.lib.SaxonOutputKeys;
import net.sf.saxon.om.NamePool;
import net.sf.saxon.serialize.charcode.CharacterSet;
import net.sf.saxon.serialize.charcode.UTF16CharacterSet;
import net.sf.saxon.serialize.charcode.UTF8CharacterSet;
import net.sf.saxon.trans.XPathException;
import javax.xml.transform.OutputKeys;
import javax.xml.transform.Result;
import javax.xml.transform.TransformerException;
import javax.xml.transform.stream.StreamResult;
import java.io.*;
import java.net.URI;
import java.net.URISyntaxException;
import java.util.Properties;
/**
* Emitter: This abstract class defines methods that must be implemented by
* components that format SAXON output. There is one emitter for XML,
* one for HTML, and so on. Additional methods are concerned with
* setting options and providing a Writer.
*
* The interface is deliberately designed to be as close as possible to the
* standard SAX2 ContentHandler interface, however, it allows additional
* information to be made available.
*
* An Emitter is a Receiver, specifically it is a Receiver that can direct output
* to a Writer or OutputStream, using serialization properties defined in a Properties
* object.
*/
public abstract class Emitter implements Result, Receiver
{
/*@NotNull*/ protected PipelineConfiguration pipelineConfig;
/*@NotNull*/ protected NamePool namePool;
protected String systemId;
protected StreamResult streamResult;
protected Writer writer;
protected OutputStream outputStream;
protected Properties outputProperties;
protected CharacterSet characterSet;
protected boolean allCharactersEncodable = false;
private boolean mustClose = false;
/**
* Set the pipelineConfiguration
*/
public void setPipelineConfiguration(/*@NotNull*/ PipelineConfiguration pipe) {
pipelineConfig = pipe;
namePool = pipe.getConfiguration().getNamePool();
}
/**
* Get the pipeline configuration used for this document
*/
/*@NotNull*/
public PipelineConfiguration getPipelineConfiguration() {
return pipelineConfig;
}
/**
* Get the configuration used for this document
* @return the configuration
*/
public Configuration getConfiguration() {
return pipelineConfig.getConfiguration();
}
/**
* Set the System ID
* @param systemId the system identifier (=base URI)
*/
public void setSystemId(String systemId) {
this.systemId = systemId;
}
/**
* Get the System ID
*/
public String getSystemId() {
return systemId;
}
/**
* Set output properties
* @param details the output serialization properties
* @throws net.sf.saxon.trans.XPathException if an error occurs finding the encoding property
*/
public void setOutputProperties(Properties details) throws XPathException {
if (characterSet==null) {
characterSet = getConfiguration().getCharacterSetFactory().getCharacterSet(details);
allCharactersEncodable = (characterSet instanceof UTF8CharacterSet ||
characterSet instanceof UTF16CharacterSet);
}
outputProperties = details;
}
/**
* Get the output properties
* @return the output serialization properties. The returned value will be null if setOutputProperties()
* has not been called
*/
public Properties getOutputProperties() {
return outputProperties;
}
/**
* Set the StreamResult acting as the output destination of the Emitter
* @param result the output destination
* @throws net.sf.saxon.trans.XPathException if an error occurs
*/
public void setStreamResult(StreamResult result) throws XPathException {
streamResult = result;
if (systemId == null) {
systemId = result.getSystemId();
}
}
/**
* Make a Writer for this Emitter to use, given a StreamResult.
* @throws net.sf.saxon.trans.XPathException if an error occurs
*/
protected void makeWriter() throws XPathException {
if (writer != null) {
return;
}
if (streamResult == null) {
throw new IllegalStateException("Emitter must have either a Writer or a StreamResult to write to");
}
writer = streamResult.getWriter();
if (writer == null) {
OutputStream os = streamResult.getOutputStream();
if (os != null) {
setOutputStream(os);
}
}
if (writer == null) {
makeOutputStream();
}
}
@SuppressWarnings({"ResultOfMethodCallIgnored"})
protected OutputStream makeOutputStream() throws XPathException {
String uriString = streamResult.getSystemId();
if (uriString == null) {
throw new XPathException("Result has no system ID, writer, or output stream defined");
}
try {
URI uri = new URI(uriString);
if (!uri.isAbsolute()) {
try {
uri = new File(uriString).getAbsoluteFile().toURI();
} catch (Exception e) {
// if we fail, we'll get another exception
}
}
File file = new File(uri);
try {
if ("file".equals(uri.getScheme()) && !file.exists()) {
File directory = file.getParentFile();
if (directory != null && !directory.exists()) {
directory.mkdirs();
}
file.createNewFile();
}
} catch (IOException err) {
throw new XPathException("Failed to create output file " + uri, err);
}
setOutputStream(new FileOutputStream(file));
// Set the outputstream in the StreamResult object so that the
// call on OutputURIResolver.close() can close it
streamResult.setOutputStream(outputStream);
mustClose = true;
} catch (FileNotFoundException fnf) {
throw new XPathException(fnf);
} catch (URISyntaxException use) {
throw new XPathException(use);
} catch (IllegalArgumentException iae) {
// for example, the system ID doesn't use the file: scheme
throw new XPathException(iae);
}
return outputStream;
}
/**
* Determine whether the Emitter wants a Writer for character output or
* an OutputStream for binary output. The standard Emitters all use a Writer, so
* this returns true; but a subclass can override this if it wants to use an OutputStream
* @return true if a Writer is needed, as distinct from an OutputStream
*/
public boolean usesWriter() {
return true;
}
/**
* Set the output destination as a character stream
* @param writer the Writer to use as an output destination
* @throws net.sf.saxon.trans.XPathException if an error occurs
*/
public void setWriter(Writer writer) throws XPathException {
this.writer = writer;
// If the writer uses a known encoding, change the encoding in the XML declaration
// to match. Any encoding actually specified in xsl:output is ignored, because encoding
// is being done by the user-supplied Writer, and not by Saxon itself.
if (writer instanceof OutputStreamWriter && outputProperties != null) {
String enc = ((OutputStreamWriter)writer).getEncoding();
outputProperties.setProperty(OutputKeys.ENCODING, enc);
characterSet = getConfiguration().getCharacterSetFactory().getCharacterSet(outputProperties);
allCharactersEncodable = (characterSet instanceof UTF8CharacterSet ||
characterSet instanceof UTF16CharacterSet);
}
}
/**
* Get the output writer
* @return the Writer being used as an output destination, if any
*/
public Writer getWriter() {
return writer;
}
/**
* Set the output destination as a byte stream.
*
Note that if a specific encoding (other than the default, UTF-8) is required, then
* {@link #setOutputProperties(java.util.Properties)} must be called before calling
* this method.
* @param stream the OutputStream being used as an output destination
* @throws net.sf.saxon.trans.XPathException if an error occurs
*/
public void setOutputStream(OutputStream stream) throws XPathException {
outputStream = stream;
// If the user supplied an OutputStream, but the Emitter is written to
// use a Writer (this is the most common case), then we create a Writer
// to wrap the supplied OutputStream; the complications are to ensure that
// the character encoding is correct.
if (usesWriter()) {
if (outputProperties == null) {
outputProperties = new Properties();
}
String encoding = outputProperties.getProperty(OutputKeys.ENCODING);
if (encoding==null) {
encoding = "UTF8";
allCharactersEncodable = true;
} else if (encoding.equalsIgnoreCase("UTF-8")) {
encoding = "UTF8";
allCharactersEncodable = true;
} else if (encoding.equalsIgnoreCase("UTF-16")) {
encoding = "UTF16";
}
if (characterSet == null) {
characterSet = getConfiguration().getCharacterSetFactory().getCharacterSet(outputProperties);
}
String byteOrderMark = outputProperties.getProperty(SaxonOutputKeys.BYTE_ORDER_MARK);
if ("no".equals(byteOrderMark) && "UTF16".equals(encoding)) {
// Java always writes a bom for UTF-16, so if the user doesn't want one, use utf16-be
encoding = "UTF-16BE";
} else if (!(characterSet instanceof UTF8CharacterSet)) {
//if (characterSet instanceof PluggableCharacterSet) {
encoding = characterSet.getCanonicalName();
}
while (true) {
try {
String javaEncoding = encoding;
if (encoding.equalsIgnoreCase("iso-646") || encoding.equalsIgnoreCase("iso646")) {
javaEncoding = "US-ASCII";
}
if (encoding.equalsIgnoreCase("UTF8")) {
writer = new UTF8Writer(outputStream);
} else {
writer = new BufferedWriter(
new OutputStreamWriter(
outputStream, javaEncoding));
}
break;
} catch (Exception err) {
if (encoding.equalsIgnoreCase("UTF8")) {
throw new XPathException("Failed to create a UTF8 output writer");
}
XPathException de = new XPathException("Encoding " + encoding + " is not supported: using UTF8");
de.setErrorCode("SESU0007");
try {
getPipelineConfiguration().getErrorListener().error(de);
} catch (TransformerException e) {
throw XPathException.makeXPathException(e);
}
encoding = "UTF8";
characterSet = UTF8CharacterSet.getInstance();
allCharactersEncodable = true;
outputProperties.setProperty(OutputKeys.ENCODING, "UTF-8");
}
}
}
}
/**
* Get the output stream
* @return the OutputStream being used as an output destination, if any
*/
public OutputStream getOutputStream() {
return outputStream;
}
/**
* Set unparsed entity URI. Needed to satisfy the Receiver interface, but not used,
* because unparsed entities can occur only in input documents, not in output documents.
* @param name the entity name
* @param uri the entity system ID
* @param publicId the entity public ID
*/
public void setUnparsedEntity(String name, String uri, String publicId) throws XPathException {}
/**
* Notify the end of the event stream
*/
public void close() throws XPathException {
if (mustClose && outputStream != null) {
try {
outputStream.close();
} catch (IOException e) {
throw new XPathException("Failed to close output stream");
}
}
}
/**
* Ask whether this Receiver (or the downstream pipeline) makes any use of the type annotations
* supplied on element and attribute events
*
* @return true if the Receiver makes any use of this information. If false, the caller
* may supply untyped nodes instead of supplying the type annotation (or conversely, it may
* avoid stripping unwanted type annotations)
*/
public boolean usesTypeAnnotations() {
return false;
}
}