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Java - How to catch all exceptions/errors from xml validating file

I woudlike to get all errors from my validating xml. Actually my method stop after catch the first error :
public List<String> validation(File file) {
SchemaFactory schemaFactory = SchemaFactory.newInstance(XMLConstants.W3C_XML_SCHEMA_NS_URI);
List<String> statut = new ArrayList<>();
try {
assert xsd != null;
Schema schema = schemaFactory.newSchema(xsd);
Validator validator = schema.newValidator();
validator.validate(new StreamSource(new File(file.getPath() + file.getname())));
statut.add(file.getname() + " is valid");
} catch (SAXException | IOException e) {
statut.add(file.getname() + " not valid :\n");
statut.add(e.getMessage());
}
return statut;
}
How can I get all exception detected ?

You can use Validator.setErrorHandler(ErrorHandler) to register your own error handler.
public abstract void setErrorHandler(ErrorHandler errorHandler)
Sets the ErrorHandler to receive errors encountered during the validate method invocation.
Error handler can be used to customize the error handling process during a validation. When an ErrorHandler is set, errors found during the validation will be first sent to the ErrorHandler.
The error handler can abort further validation immediately by throwing SAXException from the handler. Or for example it can print an error to the screen and try to continue the validation by returning normally from the ErrorHandler
If any Throwable is thrown from an ErrorHandler, the caller of the validate method will be thrown the same Throwable object.
Validator is not allowed to throw SAXException without first reporting it to ErrorHandler.
In your own error handler, you can aggregate the exceptions and then after validation, process as needed/wanted.
Specifically, it allows you to continue validation if errors are encountered enabling you to catch them all in the handler.

How to internationalization SAXParseException while parsing XML file?

I've got a problem similar to this question: SAXParseException localized
I'm trying to parse a XML file and get a list of parser errors (SAXParseException) in a several languages for example:
XmlImporter.importFile(params, "en") should return a list of errors in English, XmlImporter.importFile(params, "fr") should return a list of errors in French, XmlImporter.importFile(params, "pl") should return a list of errors in Polish language.
Every call of XmlImporter.importFile(params, "...") may be with a different locale.
This is my validation method:
private void validate(String xmlFilePath, String schemaFilePath) throws Exception {
SchemaFactory schemaFactory = SchemaFactory.newInstance(XMLConstants.W3C_XML_SCHEMA_NS_URI);
Schema schema = schemaFactory.newSchema(new File(schemaFilePath));
Validator validator = schema.newValidator();
XmlErrorHandler errorHandler = new XmlErrorHandler();
validator.setErrorHandler(errorHandler);
try (InputStream stream = new FileInputStream(new File(xmlFilePath))) {
validator.validate(new StreamSource(stream));
}
XmlErrorHandler:
public class XmlErrorHandler implements ErrorHandler {
private List<String> errorsList = new ArrayList<>();
public List<String> getErrorsList() {
return errorsList;
}
#Override
public void warning(SAXParseException exception) throws SAXException {
errorsList.add(prepareExceptionDescription(exception));
}
#Override
public void error(SAXParseException exception) throws SAXException {
errorsList.add(prepareExceptionDescription(exception));
}
#Override
public void fatalError(SAXParseException exception) throws SAXException {
errorsList.add(prepareExceptionDescription(exception));
}
private String prepareExceptionDescription(SAXParseException exception) {
return "Error: " +
"colNumber: " + exception.getColumnNumber() +
" line number: " + exception.getLineNumber() +
" message: " + exception.getLocalizedMessage();
}
}
I assume, that I need to pass somehow/somewhere java.util.Locale/String to get in exception.getLocalizedMessage() custom message (in en, fr or pl)?

By the default Xerces (Java Parser which is used to convert XML file to Java object) could provide internationalization for given languages:
XMLSchemaMessages_de.properties XMLSchemaMessages_es.properties
XMLSchemaMessages_fr.properties XMLSchemaMessages_it.properties
XMLSchemaMessages_ja.properties XMLSchemaMessages_ko.properties
XMLSchemaMessages_pt_BR.properties XMLSchemaMessages_sv.properties
XMLSchemaMessages_zh_CN.properties XMLSchemaMessages_zh_TW.properties
To provide internationalization in other language:
Get XMLSchemaMessages.properties file from Apache Xerces and rename file to a new file XMLSchemaMessages_LANG.properties, where LANG needs to be changed to a new language.
Update file's messages to a new language and place this file in a classpath (You can add this file to src\main\resources\com\sun\org\apache\xerces\internal\impl\msg)
Exceptions will be visible in a new language (messages will be taken from XMLSchemaMessages_LANG.properties file)

Capturing an exception from Xalan

I have a Java program (running in JDK 1.5 for now) which is getting a strange exception while processing an XSLT stylesheet using Xalan. I'm not looking for how to fix the exception: there's plenty of information online about that. I just want to know how to capture the exception in my code:
try {
TransformerFactory tf = TransformerFactory.newInstance();
Source src = new SAXSource(new InputSource(new FileInputStream("doc.xsl")));
Transformer t = tf.newTransformer(src);
System.out.println(t);
} catch (TransformerConfigurationException e) {
System.out.println("the exception was " + e + " and its cause is " + e.getCause());
}
and the output:
com.sun.org.apache.bcel.internal.generic.ClassGenException: Branch target offset too large for short
at com.sun.org.apache.bcel.internal.generic.BranchInstruction.dump(BranchInstruction.java:99)
at com.sun.org.apache.bcel.internal.generic.InstructionList.getByteCode(InstructionList.java:980)
at com.sun.org.apache.bcel.internal.generic.MethodGen.getMethod(MethodGen.java:616)
at com.sun.org.apache.xalan.internal.xsltc.compiler.Mode.compileNamedTemplate(Mode.java:556)
at com.sun.org.apache.xalan.internal.xsltc.compiler.Mode.compileTemplates(Mode.java:566)
at com.sun.org.apache.xalan.internal.xsltc.compiler.Mode.compileApplyTemplates(Mode.java:818)
at com.sun.org.apache.xalan.internal.xsltc.compiler.Stylesheet.compileModes(Stylesheet.java:615)
at com.sun.org.apache.xalan.internal.xsltc.compiler.Stylesheet.translate(Stylesheet.java:730)
at com.sun.org.apache.xalan.internal.xsltc.compiler.XSLTC.compile(XSLTC.java:354)
at com.sun.org.apache.xalan.internal.xsltc.compiler.XSLTC.compile(XSLTC.java:429)
at com.sun.org.apache.xalan.internal.xsltc.trax.TransformerFactoryImpl.newTemplates(TransformerFactoryImpl.java:792)
at com.sun.org.apache.xalan.internal.xsltc.trax.TransformerFactoryImpl.newTransformer(TransformerFactoryImpl.java:614)
at main.Main.main(Main.java:61)
ERROR: 'Branch target offset too large for short'
FATAL ERROR: 'Could not compile stylesheet'
the exception was javax.xml.transform.TransformerConfigurationException: Could not compile stylesheet and its cause is null
What I want to do is capture the inner exception - the ClassGenException - inside my code. Simply having it printed to STDERR as above is not useful in my application. Is there a way of doing that?

Did you try to set an ErrorListener on your TransformerFactory?
tf.setErrorListener(new ErrorListener() {
#Override
public void warning(TransformerException exception) throws TransformerException {
...
}
#Override
public void fatalError(TransformerException exception) throws TransformerException {
...
}
#Override
public void error(TransformerException exception) throws TransformerException {
...
}
});
Your ClassGenException might be available via exception.getCause().

Why am I getting "MalformedURLException: no protocol" when using SAXParser?

I'm copying code from one part of our application (an applet) to inside the app. I'm parsing XML as a String. It's been awhile since I parsed XML, but from the error that's thrown it looks like it might have to do with not finding the .dtd. The stack trace makes it difficult to find the exact cause of the error, but here's the message:
java.net.MalformedURLException: no protocol: http://www.mycomp.com/MyComp.dtd
and the XML has this as the first couple lines:
<?xml version='1.0'?>
<!DOCTYPE MYTHING SYSTEM 'http://www.mycomp.com/MyComp.dtd'>
and here's the relevant code snippets
class XMLImportParser extends DefaultHandler {
private SAXParser m_SaxParser = null;
private String is_InputString = "";
XMLImportParser(String xmlStr) throws SAXException, IOException {
super();
is_InputString = xmlStr;
createParser();
try {
preparseString();
parseString(is_InputString);
} catch (Exception e) {
throw new SAXException(e); //"Import Error : "+e.getMessage());
}
}
void createParser() throws SAXException {
SAXParserFactory factory = SAXParserFactory.newInstance();
factory.setValidating(true);
try {
factory.setFeature("http://xml.org/sax/features/namespaces", true);
factory.setFeature("http://xml.org/sax/features/namespace-prefixes", true);
m_SaxParser = factory.newSAXParser();
m_SaxParser.getXMLReader().setFeature("http://xml.org/sax/features/namespaces", true);
m_SaxParser.getXMLReader().setFeature("http://xml.org/sax/features/namespace-prefixes", true);
} catch (SAXNotRecognizedException snre){
throw new SAXException("Failed to create XML parser");
} catch (SAXNotSupportedException snse) {
throw new SAXException("Failed to create XML parser");
} catch (Exception ex) {
throw new SAXException(ex);
}
}
void preparseString() throws SAXException {
try {
InputSource lSource = new InputSource(new StringReader(is_InputString));
lSource.setEncoding("UTF-8");
m_SaxParser.parse(lSource, this);
} catch (Exception ex) {
throw new SAXException(ex);
}
}
}
It looks like the error is happening in the preparseString() method, on the line that actually does the parsing, the m_SaxParser.parse(lSource, this); line.
FYI, the 'MyComp.dtd' file does exist at that location and is accessible via http. The XML file comes from a different service on the server, so I can't change it to a file:// format and put the .dtd file on the classpath.

I think you have some extra code in the XML declaration. Try this:
<?xml version='1.0'?>
<!DOCTYPE MYTHING SYSTEM "http://www.mycomp.com/MyComp.dtd">
The above was captured from the W3C Recommendations: http://www.w3.org/QA/2002/04/valid-dtd-list.html
You can use the http link to set the Schema on the SAXParserFactory before creating your parser.
void createParser() throws SAXException {
Schema schema = SchemaFactory.newSchema(new URL("http://www.mycomp.com/MyComp.dtd"));
SAXParserFactory factory = SAXParserFactory.newInstance();
factory.setValidating(true);
factory.setSchema(schema);

The problem is that this:
http://www.mycomp.com/MyComp.dtd
is an HTML hyperlink, not a URL. Replace it with this:
http://www.mycomp.com/MyComp.dtd

Since this XML comes from an external source, the first thing to do would be to complain to them that they are sending invalid XML.
As a workaround, you can set an EntityResolver on your parser that compares the SystemId to this invalid url and returns a correct http url:
m_SaxParser.getXMLReader().setEntityResolver(
new EntityResolver() {
public InputSource resolveEntity(final String publicId, final String systemId) throws SAXException {
if ("http://www.mycomp.com/MyComp.dtd".equals(systemId)) {
return new InputSource("http://www.mycomp.com/MyComp.dtd");
} else {
return null;
}
}
}
);

How do I edit a XML node in a file object, using Java

There are a lot of examples on the internet of "reading" files but I can't find anything on "editing" a node value and writing it back out to the original file.
I have a non-working xml writer class that looks like this:
import org.w3c.dom.Document;
public class RunIt {
public static Document xmlDocument;
public static void main(String[] args)
throws TransformerException, IOException {
try {
xmlDocument = DocumentBuilderFactory.newInstance()
.newDocumentBuilder().parse("thor.xml");
} catch (IOException ex) {
ex.printStackTrace();
} catch (SAXException ex) {
ex.printStackTrace();
} catch (ParserConfigurationException ex) {
ex.printStackTrace();
}
addElement("A", "New");
writeDoc();
}
public static void addElement(String path, String val){
Element e = xmlDocument.createElement(path);
e.appendChild(xmlDocument.createTextNode(val));
xmlDocument.getDocumentElement().appendChild(e);
}
public static void writeDoc() throws TransformerException, IOException {
StringWriter writer = new StringWriter();
Transformer tf;
try {
tf = TransformerFactory.newInstance().newTransformer();
tf.transform(new DOMSource(xmlDocument), new StreamResult(writer));
writer.close();
} catch (TransformerConfigurationException e) {
e.printStackTrace();
} catch (TransformerFactoryConfigurationError e) {
e.printStackTrace();
}
}
}
For this example, lets say this is the XML and I want to add a "C" node (inside the A node) that contains the value "New" :
<A>
<B>Original</B>
</A>

You use the Document object to create new nodes. Adding nodes as you suggest involves creating a node, setting its content and then appending it to the root element. In this case your code would look somehting like this:
Element e = xmlDocument.createElement("C");
e.appendChild(xmlDocument.createTextNode("new"));
xmlDocument.getDocumentElement().appendChild(e);
This will add the C node as a new child of A right after the B node.
Additionally, Element has some convenience functions that reduce the amount of required code. The second line above could have been replaced with
e.setTextContent("new");
More complicated efforts involving non root elements will involve you using XPath to fetch the target node to be edited. If you do start to use XPath to target nodes, bear in mind that the JDK XPath performance is abysmal. Avoid using an XPath of "#foo" in favor of constructs like e.getAttribute("foo") whenever you can.
EDIT: Formatting the document back to a string which can be written to a file can be done with the following code.
Document xmlDocument;
StringWriter writer = new StringWriter();
TransformerFactory.newInstance().transform(new DOMSource(xmlDocument), new StreamResult(writer));
writer.close();
String xmlString = writer.toString();
EDIT: Re: updated question with code.
Your code doesn't work because you're conflating 'path' and 'element name'. The parameter to Document.createElement() is the name of the new node, not the location in which to place it. In the example code I wrote I didn't get into locating the appropriate node because you were asking specifically about adding a node to the document parent element. If you want your addElement() to behave the way I think you're expecting it to behave, you'd have to add another parameter for the xpath of the target parent node.
The other problem with your code is that your writeDoc() function doesn't have any output. My example shows writing the XML to a String value. You can write it to any writer you want by adapting the code, but in your example code you use a StringWriter but never extract the written string out of it.
I would suggest rewriting your code something like this
public static void main(String[] args) {
File xmlFile = new File("thor.xml");
Document xmlDocument = DocumentBuilderFactory.newInstance()
.newDocumentBuilder().parse(xmlFile);
// this is effective because we know we're adding to the
// document root element
// if you want to write to an arbitrary node, you must
// include code to find that node
addTextElement(xmlDocument.getDocumentElement(), "C", "New");
writeDoc(new FileWriter(xmlFile);
}
public static Element addTextElement(Node parent, String element, String val){
Element e = addElement(parent, element)
e.appendChild(xmlDocument.createTextNode(val));
return e;
}
public static Element addElement(Node parent, String element){
Element e = xmlDocument.createElement(path);
parent.appendChild(e);
return e;
}
public static void writeDoc(Writer writer) {
try {
Transformer tf = TransformerFactory.newInstance().newTransformer();
tf.transform(new DOMSource(xmlDocument), new StreamResult(writer));
} finally {
writer.close();
}
}

In order to write your document back to a file, you'll need an XML serializer or write your own. If you are using the Xerces library, check out XMLSerializer. For sample usage, you can also check out the DOMWriter samples page.
For more information on Xerces, read this