//$Id: XMLHelper.java 8563 2005-11-10 15:58:59Z steveebersole $
package org.hibernate.util;
import java.util.List;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.dom4j.io.DOMReader;
import org.dom4j.io.SAXReader;
import org.dom4j.io.OutputFormat;
import org.dom4j.io.XMLWriter;
import org.dom4j.Element;
import org.dom4j.DocumentFactory;
import org.xml.sax.EntityResolver;
import org.xml.sax.ErrorHandler;
import org.xml.sax.SAXParseException;
/**
* Small helper class that lazy loads DOM and SAX reader and keep them for fast use afterwards.
*
*
*
*/
public final class XMLHelper {
private static final Logger log = LoggerFactory.getLogger(XMLHelper.class);
public static final EntityResolver DEFAULT_DTD_RESOLVER = new DTDEntityResolver();
private DOMReader domReader;
private SAXReader saxReader;
/**
* Create a dom4j SAXReader which will append all validation errors
* to errorList
*/
public SAXReader createSAXReader(String file, List errorsList, EntityResolver entityResolver) {
if (saxReader==null) saxReader = new SAXReader();
saxReader.setEntityResolver(entityResolver);
saxReader.setErrorHandler( new ErrorLogger(file, errorsList) );
saxReader.setMergeAdjacentText(true);
saxReader.setValidation(true);
return saxReader;
}
/**
* Create a dom4j DOMReader
*/
public DOMReader createDOMReader() {
if (domReader==null) domReader = new DOMReader();
return domReader;
}
public static class ErrorLogger implements ErrorHandler {
private String file;
private List errors;
ErrorLogger(String file, List errors) {
this.file=file;
this.errors = errors;
}
public void error(SAXParseException error) {
log.error( "Error parsing XML: " + file + '(' + error.getLineNumber() + ") " + error.getMessage() );
errors.add(error);
}
public void fatalError(SAXParseException error) {
error(error);
}
public void warning(SAXParseException warn) {
log.warn( "Warning parsing XML: " + file + '(' + warn.getLineNumber() + ") " + warn.getMessage() );
}
}
public static Element generateDom4jElement(String elementName) {
return DocumentFactory.getInstance().createElement( elementName );
}
public static void dump(Element element) {
try {
// try to "pretty print" it
OutputFormat outformat = OutputFormat.createPrettyPrint();
XMLWriter writer = new XMLWriter( System.out, outformat );
writer.write( element );
writer.flush();
System.out.println( "" );
}
catch( Throwable t ) {
// otherwise, just dump it
System.out.println( element.asXML() );
}
}
}