net.sf.saxon.trace.ExpressionPresenter Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of saxon-he Show documentation
Show all versions of saxon-he Show documentation
An OSGi bundle for Saxon-HE
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// 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.trace;
import net.sf.saxon.Configuration;
import net.sf.saxon.event.Receiver;
import net.sf.saxon.lib.SaxonOutputKeys;
import net.sf.saxon.om.NamePool;
import net.sf.saxon.om.NoNamespaceName;
import net.sf.saxon.trans.XPathException;
import net.sf.saxon.type.BuiltInAtomicType;
import net.sf.saxon.type.TypeHierarchy;
import net.sf.saxon.type.Untyped;
import javax.xml.transform.OutputKeys;
import javax.xml.transform.stream.StreamResult;
import java.io.OutputStream;
import java.util.Properties;
/**
* This class handles the display of an abstract expression tree in an XML format
* with some slight resemblence to XQueryX
*/
public class ExpressionPresenter {
private Configuration config;
/*@Nullable*/ private Receiver receiver;
int depth = 0;
boolean inStartTag = false;
/**
* Make an ExpressionPresenter that writes indented output to the standard error output
* destination of the Configuration
* @param config the Saxon configuration
*/
public ExpressionPresenter(/*@NotNull*/ Configuration config) {
this(config, config.getStandardErrorOutput());
}
/**
* Make an ExpressionPresenter that writes indented output to a specified output stream
* @param config the Saxon configuration
* @param out the output stream
*/
public ExpressionPresenter(/*@NotNull*/ Configuration config, OutputStream out) {
Properties props = makeDefaultProperties();
try {
receiver = config.getSerializerFactory().getReceiver(
new StreamResult(out),
config.makePipelineConfiguration(),
props);
} catch (XPathException err) {
err.printStackTrace();
throw new InternalError(err.getMessage());
}
this.config = config;
try {
receiver.open();
receiver.startDocument(0);
} catch (XPathException err) {
err.printStackTrace();
throw new InternalError(err.getMessage());
}
}
/**
* Make an ExpressionPresenter for a given Configuration using a user-supplied Receiver
* to accept the output
* @param config the Configuration
* @param receiver the user-supplied Receiver
*/
public ExpressionPresenter(Configuration config, /*@NotNull*/ Receiver receiver) {
this.config = config;
this.receiver = receiver;
try {
receiver.open();
receiver.startDocument(0);
} catch (XPathException err) {
err.printStackTrace();
throw new InternalError(err.getMessage());
}
}
/**
* Make a receiver, using default output properties, with serialized output going
* to a specified OutputStream
* @param config the Configuration
* @param out the OutputStream
* @return a Receiver that directs serialized output to this output stream
* @throws XPathException
*/
/*@Nullable*/ public static Receiver defaultDestination(/*@NotNull*/ Configuration config, OutputStream out) throws XPathException {
Properties props = makeDefaultProperties();
return config.getSerializerFactory().getReceiver(
new StreamResult(out),
config.makePipelineConfiguration(),
props);
}
/**
* Make a Properties object containing defaulted serialization attributes for the expression tree
* @return a default set of properties
*/
/*@NotNull*/ public static Properties makeDefaultProperties() {
Properties props = new Properties();
props.setProperty(OutputKeys.METHOD, "xml");
props.setProperty(OutputKeys.INDENT, "yes");
props.setProperty(OutputKeys.OMIT_XML_DECLARATION, "yes");
props.setProperty(SaxonOutputKeys.INDENT_SPACES, "2");
return props;
}
/**
* Start an element
* @param name the name of the element
* @return the depth of the tree before this element: for diagnostics, this can be compared
* with the value returned by endElement
*/
public int startElement(String name) {
try {
if (inStartTag) {
receiver.startContent();
inStartTag = false;
}
receiver.startElement(new NoNamespaceName(name), Untyped.getInstance(), 0, 0);
} catch (XPathException err) {
err.printStackTrace();
throw new InternalError(err.getMessage());
}
inStartTag = true;
return depth++;
}
/**
* Output an attribute node
* @param name the name of the attribute
* @param value the value of the attribute
*/
public void emitAttribute(String name, String value) {
try {
receiver.attribute(new NoNamespaceName(name), BuiltInAtomicType.UNTYPED_ATOMIC, value, 0, 0);
} catch (XPathException err) {
err.printStackTrace();
throw new InternalError(err.getMessage());
}
}
/**
* End an element in the expression tree
* @return the depth of the tree after ending this element. For diagnostics, this can be compared with the
* value returned by startElement()
*/
public int endElement() {
try {
if (inStartTag) {
receiver.startContent();
inStartTag = false;
}
receiver.endElement();
} catch (XPathException err) {
err.printStackTrace();
throw new InternalError(err.getMessage());
}
return --depth;
}
/**
* Start a child element in the output
* @param name the name of the child element
*/
public void startSubsidiaryElement(String name) {
startElement(name);
}
/**
* End a child element in the output
*/
public void endSubsidiaryElement() {
endElement();
}
/**
* Close the output
*/
public void close() {
try {
receiver.endDocument();
receiver.close();
} catch (XPathException err) {
err.printStackTrace();
throw new InternalError(err.getMessage());
}
}
/**
* Get the Saxon configuration
* @return the Saxon configuration
*/
public Configuration getConfiguration() {
return config;
}
/**
* Get the name pool
* @return the name pool
*/
public NamePool getNamePool() {
return config.getNamePool();
}
/**
* Get the type hierarchy cache
* @return the type hierarchy cache
*/
public TypeHierarchy getTypeHierarchy() {
return config.getTypeHierarchy();
}
}