groovy.xml.XmlParser Maven / Gradle / Ivy
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* 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 groovy.xml;
import groovy.namespace.QName;
import groovy.util.Node;
import org.xml.sax.Attributes;
import org.xml.sax.ContentHandler;
import org.xml.sax.DTDHandler;
import org.xml.sax.EntityResolver;
import org.xml.sax.ErrorHandler;
import org.xml.sax.InputSource;
import org.xml.sax.Locator;
import org.xml.sax.SAXException;
import org.xml.sax.SAXNotRecognizedException;
import org.xml.sax.SAXNotSupportedException;
import org.xml.sax.XMLReader;
import javax.xml.XMLConstants;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.Reader;
import java.io.StringReader;
import java.util.ArrayList;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
import static groovy.xml.XmlUtil.setFeatureQuietly;
/**
* A helper class for parsing XML into a tree of Node instances for a
* simple way of processing XML. This parser does not preserve the XML
* InfoSet - if that's what you need try using W3C DOM, dom4j, JDOM, XOM etc.
* This parser ignores comments and processing instructions and converts
* the XML into a Node for each element in the XML with attributes
* and child Nodes and Strings. This simple model is sufficient for
* most simple use cases of processing XML.
*
* Example usage:
*
* import groovy.xml.XmlParser
* def xml = '<root><one a1="uno!"/><two>Some text!</two></root>'
* def rootNode = new XmlParser().parseText(xml)
* assert rootNode.name() == 'root'
* assert rootNode.one[0].@a1 == 'uno!'
* assert rootNode.two.text() == 'Some text!'
* rootNode.children().each { assert it.name() in ['one','two'] }
*
*/
public class XmlParser implements ContentHandler {
private StringBuilder bodyText = new StringBuilder();
private final List stack = new ArrayList();
private Locator locator;
private final XMLReader reader;
private Node parent;
private boolean trimWhitespace = false;
private boolean keepIgnorableWhitespace = false;
private boolean namespaceAware;
/**
* Creates a non-validating and namespace-aware XmlParser which does not allow DOCTYPE declarations in documents.
*
* @throws ParserConfigurationException if no parser which satisfies the requested configuration can be created.
* @throws SAXException for SAX errors.
*/
public XmlParser() throws ParserConfigurationException, SAXException {
this(false, true);
}
/**
* Creates a XmlParser which does not allow DOCTYPE declarations in documents.
*
* @param validating true if the parser should validate documents as they are parsed; false otherwise.
* @param namespaceAware true if the parser should provide support for XML namespaces; false otherwise.
* @throws ParserConfigurationException if no parser which satisfies the requested configuration can be created.
* @throws SAXException for SAX errors.
*/
public XmlParser(boolean validating, boolean namespaceAware) throws ParserConfigurationException, SAXException {
this(validating, namespaceAware, false);
}
/**
* Creates a XmlParser.
*
* @param validating true if the parser should validate documents as they are parsed; false otherwise.
* @param namespaceAware true if the parser should provide support for XML namespaces; false otherwise.
* @param allowDocTypeDeclaration true if the parser should provide support for DOCTYPE declarations; false otherwise.
* @throws ParserConfigurationException if no parser which satisfies the requested configuration can be created.
* @throws SAXException for SAX errors.
*/
public XmlParser(boolean validating, boolean namespaceAware, boolean allowDocTypeDeclaration) throws ParserConfigurationException, SAXException {
SAXParserFactory factory = FactorySupport.createSaxParserFactory();
factory.setNamespaceAware(namespaceAware);
this.namespaceAware = namespaceAware;
factory.setValidating(validating);
setFeatureQuietly(factory, XMLConstants.FEATURE_SECURE_PROCESSING, true);
setFeatureQuietly(factory, "http://apache.org/xml/features/disallow-doctype-decl", !allowDocTypeDeclaration);
reader = factory.newSAXParser().getXMLReader();
}
public XmlParser(XMLReader reader) {
this.reader = reader;
}
public XmlParser(SAXParser parser) throws SAXException {
reader = parser.getXMLReader();
}
/**
* Returns the current trim whitespace setting.
*
* @return true if whitespace will be trimmed
*/
public boolean isTrimWhitespace() {
return trimWhitespace;
}
/**
* Sets the trim whitespace setting value.
*
* @param trimWhitespace the desired setting value
*/
public void setTrimWhitespace(boolean trimWhitespace) {
this.trimWhitespace = trimWhitespace;
}
/**
* Returns the current keep ignorable whitespace setting.
*
* @return true if ignorable whitespace will be kept (default false)
*/
public boolean isKeepIgnorableWhitespace() {
return keepIgnorableWhitespace;
}
/**
* Sets the keep ignorable whitespace setting value.
*
* @param keepIgnorableWhitespace the desired new value
*/
public void setKeepIgnorableWhitespace(boolean keepIgnorableWhitespace) {
this.keepIgnorableWhitespace = keepIgnorableWhitespace;
}
/**
* Parses the content of the given file as XML turning it into a tree
* of Nodes.
*
* @param file the File containing the XML to be parsed
* @return the root node of the parsed tree of Nodes
* @throws SAXException Any SAX exception, possibly
* wrapping another exception.
* @throws IOException An IO exception from the parser,
* possibly from a byte stream or character stream
* supplied by the application.
*/
public Node parse(File file) throws IOException, SAXException {
InputSource input = new InputSource(new FileInputStream(file));
input.setSystemId("file://" + file.getAbsolutePath());
getXMLReader().parse(input);
return parent;
}
/**
* Parse the content of the specified input source into a tree of Nodes.
*
* @param input the InputSource for the XML to parse
* @return the root node of the parsed tree of Nodes
* @throws SAXException Any SAX exception, possibly
* wrapping another exception.
* @throws IOException An IO exception from the parser,
* possibly from a byte stream or character stream
* supplied by the application.
*/
public Node parse(InputSource input) throws IOException, SAXException {
getXMLReader().parse(input);
return parent;
}
/**
* Parse the content of the specified input stream into a tree of Nodes.
*
* Note that using this method will not provide the parser with any URI
* for which to find DTDs etc
*
* @param input an InputStream containing the XML to be parsed
* @return the root node of the parsed tree of Nodes
* @throws SAXException Any SAX exception, possibly
* wrapping another exception.
* @throws IOException An IO exception from the parser,
* possibly from a byte stream or character stream
* supplied by the application.
*/
public Node parse(InputStream input) throws IOException, SAXException {
InputSource is = new InputSource(input);
getXMLReader().parse(is);
return parent;
}
/**
* Parse the content of the specified reader into a tree of Nodes.
*
* Note that using this method will not provide the parser with any URI
* for which to find DTDs etc
*
* @param in a Reader to read the XML to be parsed
* @return the root node of the parsed tree of Nodes
* @throws SAXException Any SAX exception, possibly
* wrapping another exception.
* @throws IOException An IO exception from the parser,
* possibly from a byte stream or character stream
* supplied by the application.
*/
public Node parse(Reader in) throws IOException, SAXException {
InputSource is = new InputSource(in);
getXMLReader().parse(is);
return parent;
}
/**
* Parse the content of the specified URI into a tree of Nodes.
*
* @param uri a String containing a URI pointing to the XML to be parsed
* @return the root node of the parsed tree of Nodes
* @throws SAXException Any SAX exception, possibly
* wrapping another exception.
* @throws IOException An IO exception from the parser,
* possibly from a byte stream or character stream
* supplied by the application.
*/
public Node parse(String uri) throws IOException, SAXException {
InputSource is = new InputSource(uri);
getXMLReader().parse(is);
return parent;
}
/**
* A helper method to parse the given text as XML.
*
* @param text the XML text to parse
* @return the root node of the parsed tree of Nodes
* @throws SAXException Any SAX exception, possibly
* wrapping another exception.
* @throws IOException An IO exception from the parser,
* possibly from a byte stream or character stream
* supplied by the application.
*/
public Node parseText(String text) throws IOException, SAXException {
return parse(new StringReader(text));
}
/**
* Determine if namespace handling is enabled.
*
* @return true if namespace handling is enabled
*/
public boolean isNamespaceAware() {
return namespaceAware;
}
/**
* Enable and/or disable namespace handling.
*
* @param namespaceAware the new desired value
*/
public void setNamespaceAware(boolean namespaceAware) {
this.namespaceAware = namespaceAware;
}
// Delegated XMLReader methods
//------------------------------------------------------------------------
/* (non-Javadoc)
* @see org.xml.sax.XMLReader#getDTDHandler()
*/
public DTDHandler getDTDHandler() {
return this.reader.getDTDHandler();
}
/* (non-Javadoc)
* @see org.xml.sax.XMLReader#getEntityResolver()
*/
public EntityResolver getEntityResolver() {
return this.reader.getEntityResolver();
}
/* (non-Javadoc)
* @see org.xml.sax.XMLReader#getErrorHandler()
*/
public ErrorHandler getErrorHandler() {
return this.reader.getErrorHandler();
}
/* (non-Javadoc)
* @see org.xml.sax.XMLReader#getFeature(java.lang.String)
*/
public boolean getFeature(final String uri) throws SAXNotRecognizedException, SAXNotSupportedException {
return this.reader.getFeature(uri);
}
/* (non-Javadoc)
* @see org.xml.sax.XMLReader#getProperty(java.lang.String)
*/
public Object getProperty(final String uri) throws SAXNotRecognizedException, SAXNotSupportedException {
return this.reader.getProperty(uri);
}
/* (non-Javadoc)
* @see org.xml.sax.XMLReader#setDTDHandler(org.xml.sax.DTDHandler)
*/
public void setDTDHandler(final DTDHandler dtdHandler) {
this.reader.setDTDHandler(dtdHandler);
}
/* (non-Javadoc)
* @see org.xml.sax.XMLReader#setEntityResolver(org.xml.sax.EntityResolver)
*/
public void setEntityResolver(final EntityResolver entityResolver) {
this.reader.setEntityResolver(entityResolver);
}
/* (non-Javadoc)
* @see org.xml.sax.XMLReader#setErrorHandler(org.xml.sax.ErrorHandler)
*/
public void setErrorHandler(final ErrorHandler errorHandler) {
this.reader.setErrorHandler(errorHandler);
}
/* (non-Javadoc)
* @see org.xml.sax.XMLReader#setFeature(java.lang.String, boolean)
*/
public void setFeature(final String uri, final boolean value) throws SAXNotRecognizedException, SAXNotSupportedException {
this.reader.setFeature(uri, value);
}
/* (non-Javadoc)
* @see org.xml.sax.XMLReader#setProperty(java.lang.String, java.lang.Object)
*/
public void setProperty(final String uri, final Object value) throws SAXNotRecognizedException, SAXNotSupportedException {
reader.setProperty(uri, value);
}
// ContentHandler interface
//-------------------------------------------------------------------------
@Override
public void startDocument() throws SAXException {
parent = null;
}
@Override
public void endDocument() throws SAXException {
stack.clear();
}
@Override
public void startElement(String namespaceURI, String localName, String qName, Attributes list)
throws SAXException {
addTextToNode();
Object nodeName = getElementName(namespaceURI, localName, qName);
int size = list.getLength();
Map attributes = new LinkedHashMap(size);
for (int i = 0; i < size; i++) {
Object attributeName = getElementName(list.getURI(i), list.getLocalName(i), list.getQName(i));
String value = list.getValue(i);
attributes.put(attributeName, value);
}
parent = createNode(parent, nodeName, attributes);
stack.add(parent);
}
@Override
public void endElement(String namespaceURI, String localName, String qName) throws SAXException {
addTextToNode();
if (!stack.isEmpty()) {
stack.remove(stack.size() - 1);
if (!stack.isEmpty()) {
parent = stack.get(stack.size() - 1);
}
}
}
@Override
public void characters(char[] buffer, int start, int length) throws SAXException {
bodyText.append(buffer, start, length);
}
@Override
public void startPrefixMapping(String prefix, String namespaceURI) throws SAXException {
}
@Override
public void endPrefixMapping(String prefix) throws SAXException {
}
@Override
public void ignorableWhitespace(char[] buffer, int start, int len) throws SAXException {
if (keepIgnorableWhitespace) characters(buffer, start, len);
}
@Override
public void processingInstruction(String target, String data) throws SAXException {
}
public Locator getDocumentLocator() {
return locator;
}
@Override
public void setDocumentLocator(Locator locator) {
this.locator = locator;
}
@Override
public void skippedEntity(String name) throws SAXException {
}
// Implementation methods
//-------------------------------------------------------------------------
protected XMLReader getXMLReader() {
reader.setContentHandler(this);
return reader;
}
protected void addTextToNode() {
if (parent == null) {
// TODO store this on root node? reset bodyText?
return;
}
String text = bodyText.toString();
if (!trimWhitespace && keepIgnorableWhitespace) {
parent.children().add(text);
} else if (!trimWhitespace && text.trim().length() > 0) {
parent.children().add(text);
} else if (text.trim().length() > 0) {
parent.children().add(text.trim());
}
bodyText = new StringBuilder();
}
/**
* Creates a new node with the given parent, name, and attributes. The
* default implementation returns an instance of
* groovy.util.Node.
*
* @param parent the parent node, or null if the node being created is the
* root node
* @param name an Object representing the name of the node (typically
* an instance of {@link QName})
* @param attributes a Map of attribute names to attribute values
* @return a new Node instance representing the current node
*/
protected Node createNode(Node parent, Object name, Map attributes) {
return new Node(parent, name, attributes);
}
/**
* Return a name given the namespaceURI, localName and qName.
*
* @param namespaceURI the namespace URI
* @param localName the local name
* @param qName the qualified name
* @return the newly created representation of the name
*/
protected Object getElementName(String namespaceURI, String localName, String qName) {
String name = localName;
String prefix = "";
if ((name == null) || (name.length() < 1)) {
name = qName;
}
if (namespaceURI == null || namespaceURI.length() <= 0) {
return name;
}
if (qName != null && qName.length() > 0 && namespaceAware) {
int index = qName.lastIndexOf(':');
if (index > 0) {
prefix = qName.substring(0, index);
}
}
return new QName(namespaceURI, name, prefix);
}
}