I convert an XML file to PDF, through XSL-LO.
This process involves a Transformer based on a XSLT file.
This is how I get the Transformer:
private void prepareTransformer(final TransformerFactory tFactory)
throws TransformerConfigurationException {
xmlTransformer = tFactory.newTransformer(
new StreamSource(getClass().getResourceAsStream(xsltPath)));
}
My problem is that if the XSLT is not well formed, then the above mentioned code would logs an exception but not throws it. This is the output in the console:
System-ID unbekannt; Zeilennummer328; Spaltennummer69; xsl:when ist an dieser Position in der Formatvorlage nicht zulässig!
System-ID unbekannt; Zeilennummer63; Spaltennummer54; org.xml.sax.SAXException: javax.xml.transform.TransformerException: ElemTemplateElement-Fehler: testcaseDetails
javax.xml.transform.TransformerException: ElemTemplateElement-Fehler: testcaseDetails
(Position des Fehlers unbekannt)org.apache.fop.fo.ValidationException: Dem Element "fo:simple-page-master" fehlt ein verlangtes Property "master-name"! (Keine Kontextinformationen verfügbar)
As no exception is thrown by the librairy, I can not so easily handle this situation.
Expected behaviour: #newTransformer(Source source) would throw an exception. Is there a way to achieve that?
EDIT: here the full class:
#Log
public class Report {
private final String xsltPath;
private FopFactory fopFactory;
private Transformer xmlTransformer;
private Report(final String xsltPath) {
this.xsltPath = xsltPath;
try {
prepareTransformer(createFobTransformer());
} catch (final SAXException | IOException | ConfigurationException |
TransformerConfigurationException ex) {
log.log(Level.SEVERE, null, ex);
throw new PdfReportException(ex);
}
}
public static Report getInstance() {
return new Report("/report/report-regd.xslt");
}
private void prepareTransformer(final TransformerFactory tFactory)
throws TransformerConfigurationException {
xmlTransformer = tFactory.newTransformer(
new StreamSource(getClass().getResourceAsStream(xsltPath)));
}
private TransformerFactory createFobTransformer()
throws SAXException, IOException, ConfigurationException {
final InputStream inFop = getClass().getResourceAsStream("/report/fop.xconf");
final var fopBuilder = new FopFactoryBuilder(new File(".").toURI(),
new ClasspathResolverURIAdapter());
final var cfgBuilder = new DefaultConfigurationBuilder();
final Configuration cfg = cfgBuilder.build(inFop);
fopBuilder.setConfiguration(cfg);
fopFactory = fopBuilder.build();
final TransformerFactory tFactory = TransformerFactory.newInstance();
tFactory.setURIResolver(new ClasspathURIResolver());
return tFactory;
}
public byte[] generatePDFReport(final String xml) {
final var out = new ByteArrayOutputStream();
final var agent = fopFactory.newFOUserAgent();
try {
final var fop = agent.newFop(MimeConstants.MIME_PDF, out);
final var result = new SAXResult(fop.getDefaultHandler());
final var src = new StreamSource(new StringReader(xml));
xmlTransformer.transform(src, result);
} catch (final FOPException | TransformerException e) {
throw new PdfReportException(e);
}
return out.toByteArray();
}
public static class PdfReportException extends RuntimeException {
private static final long serialVersionUID = 6009368304491510184L;
public PdfReportException(final Throwable cause) {
super(cause);
}
}
}
No exception is catched in Report constructor:
I am working on an API that will return an JSON response from an XML source. I have used RestTemplate and JAXB to get the XML string from the source and then used StringReader and Unmarshaller to create the Java object. The object looks like this;
#XmlRootElement(name="ItemSearchResponse", namespace="http://webservices.amazon.com/AWSECommerceService/2011-08-01") //
#XmlAccessorType(XmlAccessType.FIELD)
public class SampleXML {
#XmlAccessorType(XmlAccessType.FIELD)
#XmlType
public static class OperationRequest {
#XmlTransient
private String RequestId;
#XmlElement(name="RequestId")
public void setRequestId(String id) {
this.RequestId = id;
}
public String getRequestId() {
return RequestId;
}
...
This is the code that should return the JSON string to the browser;
#RequestMapping("/samplexml2")
public SampleXML CreateXMLFile2 () throws EncoderException, FileNotFoundException, SAXException {
try {
String requestUrl = null;
RestTemplate restTemplate = new RestTemplate();
restTemplate.setErrorHandler(new ResponseErrorHandler());
String decodedUrl = "http://localhost:8080/sample.xml";
String response = restTemplate.getForObject(decodedUrl, String.class);
//Prepare JAXB objects
JAXBContext jaxbContext = JAXBContext.newInstance(SampleXML.class);
Unmarshaller u = jaxbContext.createUnmarshaller();
//Create an XMLReader to use with our filter
XMLReader reader = XMLReaderFactory.createXMLReader();
//Create the filter (to add namespace) and set the xmlReader as its parent.
NamespaceFilter inFilter = new NamespaceFilter("http://webservices.amazon.com/AWSECommerceService/2011-08-01", true);
inFilter.setParent(reader);
//Prepare the input, in this case a java.io.File (output)
InputSource is = new InputSource(new StringReader(response));
//Create a SAXSource specifying the filter
SAXSource source = new SAXSource(inFilter, is);
//Do unmarshalling
SampleXML myJaxbObject = (SampleXML) u.unmarshal(source);
//Convert to myJaxbObject to JSON string here;
return myJaxbObject;
} catch (JAXBException e) {
e.printStackTrace();
return null;
}
}
I want to write the conversation at this line; //Convert to myJaxbObject to JSON string here;
I have read many articles that point to this library; https://github.com/FasterXML/jackson-module-jaxb-annotations But I have not been able to use it successfully.
I would like an example that uses Jackson or MOXy dependencies
Have you tried simply changing your RequestMapping to #RequestMapping(value = "/samplexml2", produces = MediaType.APPLICATION_JSON_VALUE)?
I'm trying to write a method to pretty print JSON Strings, using MOXy. So what I want is to have a method like this
public String formatJson(String input) { ... }
I think the way to go is to parse the String to a generic Object (Something like a SAX-Document, or the kind), and then marshal this Object back to JSON using some formatting properties (which is not the problem :-) ).
The Problem is, when reading the JSON-String-Input, I don't have a Class to unmarshal to (as I want the method to be as generic as possible).
[edited] GSON and Jackson examples removed, as only MOXy is the question.
I tried this:
public static String toFormattedJson(final String jsonString) {
String formatted;
try {
JAXBContext jaxbContext = JAXBContextFactory.createContext(new Class[] { JAXBElement.class }, null);
Unmarshaller unmarshaller = jaxbContext.createUnmarshaller();
unmarshaller.setProperty(MEDIA_TYPE, MediaType.APPLICATION_JSON);
unmarshaller.setProperty(JSON_INCLUDE_ROOT, true);
StringReader reader = new StringReader(jsonString);
Object element = unmarshaller.unmarshal(reader); // Exception is thrown here
formatted = toFormattedJson(element);
} catch (final JAXBException e) {
formatted = jsonString;
}
return formatted;
}
but I get an this Exception
javax.xml.bind.UnmarshalException
- with linked exception:
[java.lang.ClassCastException: org.eclipse.persistence.internal.oxm.record.SAXUnmarshallerHandler cannot be cast to org.eclipse.persistence.internal.oxm.record.UnmarshalRecord]
So how can I read an arbitrary JSON String in to a Java Object, if I don't have any Class for that specific String?
Update:
This is the method used to format an Object into a JSON String:
private static String toFormattedJson(Object obj) {
String result;
try (StringWriter writer = new StringWriter()) {
final JAXBContext jaxbContext = JAXBContextFactory.createContext(new Class[] { obj.getClass() }, null);
final Marshaller marshaller = jaxbContext.createMarshaller();
marshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, true);
marshaller.setProperty(JAXBContextProperties.MEDIA_TYPE, MediaType.APPLICATION_JSON);
marshaller.setProperty(MarshallerProperties.JSON_REDUCE_ANY_ARRAYS, false);
marshaller.setProperty(MarshallerProperties.JSON_MARSHAL_EMPTY_COLLECTIONS, false);
marshaller.setProperty(JAXBContextProperties.JSON_WRAPPER_AS_ARRAY_NAME, false);
marshaller.setProperty(JAXBContextProperties.JSON_INCLUDE_ROOT, true);
marshaller.marshal(obj, writer);
writer.flush();
result = writer.toString();
} catch (JAXBException | IOException e) {
result = obj.toString();
}
return result;
}
And using now the code from below (Martin Vojtek), when I try to format
String jsonString = "{\"p\" : [ 1, 2, 3]}";
I get:
{
"p" : "1"
}
You can specify String as the unmarshal target:
public static void main(String[] args) {
System.out.println(toFormattedJson("[{\"test\":true}, \"ok\", [\"inner\",1]]"));
}
public static String toFormattedJson(final String jsonString) {
String formatted;
try {
JAXBContext jaxbContext = JAXBContextFactory.createContext(new Class[] { JAXBElement.class }, null);
System.out.println("jaxbContext="+jaxbContext);
Unmarshaller unmarshaller = jaxbContext.createUnmarshaller();
unmarshaller.setProperty(JAXBContextProperties.MEDIA_TYPE, MediaType.APPLICATION_JSON);
unmarshaller.setProperty(JAXBContextProperties.JSON_INCLUDE_ROOT, true);
StringReader reader = new StringReader(jsonString);
Object element = unmarshaller.unmarshal(new StreamSource(reader), String.class);
formatted = toFormattedJsonElement(element);
} catch (final JAXBException e) {
e.printStackTrace();
formatted = jsonString;
}
return formatted;
}
private static String toFormattedJsonElement(Object element) {
return "formatted: " + element;
}
I want to ignore external entities and external stylesheets (eg. <?xml-stylesheet type="text/xsl" href="......."?>).
I know I have to set XMLReader property to ignore external entities but I don't know how to ignore stylesheets...
import org.apache.xerces.parsers.SAXParser;
import org.xml.sax.XMLReader;
//...
final XMLReader parser = new SAXParser();
// Ignore entities
parser.setProperty("http://xml.org/sax/features/external-general-entities", false);
// IS CORRECT???
parser.setProperty("http://xml.org/sax/features/external-general-entities", false);
There are more properties to set to avoid external entities and stylesheet?
How Can I understand if there are external entities o stylesheets?
Working for me:
public class SaxParser extends DefaultHandler
implements ContentHandler, DTDHandler, EntityResolver{
public transient static final String STYLE_SHEET_TAG = "xml-stylesheet";
public transient static final String EXTERNAL_ENTITY = "ExternalEntity";
public static void main(String[] args) {
new SaxParser().execute();
}
public void execute() {
String pathFileXml = "test/XML.xml";
final XMLReader parser = new SAXParser();
parser.setContentHandler(this);
parser.setDTDHandler(this);
parser.setEntityResolver(this);
try {
parser.parse(pathFileXml);
} catch (IOException e) {
e.printStackTrace();
} catch (SAXException e) {
if (SaxParser.STYLE_SHEET_TAG.equals(e.getMessage())
|| SaxParser.EXTERNAL_ENTITY.equals(e.getMessage())) {
System.out.println("CATCH ERRORE");
}
e.printStackTrace();
}
System.out.println("OK");
}
#Override
public void processingInstruction(String target, String data)
throws SAXException {
System.out.println("Processing Instruction");
System.out.println("PI=> target: " + target + ", data: " + data);
if (STYLE_SHEET_TAG.equalsIgnoreCase(target.trim())) {
throw new SAXException(STYLE_SHEET_TAG);
}
return;
}
#Override
public InputSource resolveEntity(String publicId, String systemId)
throws IOException, SAXException {
System.out.println("publicId: " + publicId + ", systemId: " + systemId);
throw new SAXException(SaxParser.EXTERNAL_ENTITY);
}
}
The external stylesheet declaration is a standard processing instruction.
You can ignore processing instructions by not implementing the handler method:
void processingInstruction(java.lang.String target, java.lang.String data) {}
in your SAX handler.
My schema specifies a namespace, but the documents don't. What's the simplest way to ignore namespace during JAXB unmarshalling (XML -> object)?
In other words, I have
<foo><bar></bar></foo>
instead of,
<foo xmlns="http://tempuri.org/"><bar></bar></foo>
Here is an extension/edit of VonCs solution just in case someone doesn´t want to go through the hassle of implementing their own filter to do this. It also shows how to output a JAXB element without the namespace present. This is all accomplished using a SAX Filter.
Filter implementation:
import org.xml.sax.Attributes;
import org.xml.sax.SAXException;
import org.xml.sax.helpers.XMLFilterImpl;
public class NamespaceFilter extends XMLFilterImpl {
private String usedNamespaceUri;
private boolean addNamespace;
//State variable
private boolean addedNamespace = false;
public NamespaceFilter(String namespaceUri,
boolean addNamespace) {
super();
if (addNamespace)
this.usedNamespaceUri = namespaceUri;
else
this.usedNamespaceUri = "";
this.addNamespace = addNamespace;
}
#Override
public void startDocument() throws SAXException {
super.startDocument();
if (addNamespace) {
startControlledPrefixMapping();
}
}
#Override
public void startElement(String arg0, String arg1, String arg2,
Attributes arg3) throws SAXException {
super.startElement(this.usedNamespaceUri, arg1, arg2, arg3);
}
#Override
public void endElement(String arg0, String arg1, String arg2)
throws SAXException {
super.endElement(this.usedNamespaceUri, arg1, arg2);
}
#Override
public void startPrefixMapping(String prefix, String url)
throws SAXException {
if (addNamespace) {
this.startControlledPrefixMapping();
} else {
//Remove the namespace, i.e. don´t call startPrefixMapping for parent!
}
}
private void startControlledPrefixMapping() throws SAXException {
if (this.addNamespace && !this.addedNamespace) {
//We should add namespace since it is set and has not yet been done.
super.startPrefixMapping("", this.usedNamespaceUri);
//Make sure we dont do it twice
this.addedNamespace = true;
}
}
}
This filter is designed to both be able to add the namespace if it is not present:
new NamespaceFilter("http://www.example.com/namespaceurl", true);
and to remove any present namespace:
new NamespaceFilter(null, false);
The filter can be used during parsing as follows:
//Prepare JAXB objects
JAXBContext jc = JAXBContext.newInstance("jaxb.package");
Unmarshaller u = jc.createUnmarshaller();
//Create an XMLReader to use with our filter
XMLReader reader = XMLReaderFactory.createXMLReader();
//Create the filter (to add namespace) and set the xmlReader as its parent.
NamespaceFilter inFilter = new NamespaceFilter("http://www.example.com/namespaceurl", true);
inFilter.setParent(reader);
//Prepare the input, in this case a java.io.File (output)
InputSource is = new InputSource(new FileInputStream(output));
//Create a SAXSource specifying the filter
SAXSource source = new SAXSource(inFilter, is);
//Do unmarshalling
Object myJaxbObject = u.unmarshal(source);
To use this filter to output XML from a JAXB object, have a look at the code below.
//Prepare JAXB objects
JAXBContext jc = JAXBContext.newInstance("jaxb.package");
Marshaller m = jc.createMarshaller();
//Define an output file
File output = new File("test.xml");
//Create a filter that will remove the xmlns attribute
NamespaceFilter outFilter = new NamespaceFilter(null, false);
//Do some formatting, this is obviously optional and may effect performance
OutputFormat format = new OutputFormat();
format.setIndent(true);
format.setNewlines(true);
//Create a new org.dom4j.io.XMLWriter that will serve as the
//ContentHandler for our filter.
XMLWriter writer = new XMLWriter(new FileOutputStream(output), format);
//Attach the writer to the filter
outFilter.setContentHandler(writer);
//Tell JAXB to marshall to the filter which in turn will call the writer
m.marshal(myJaxbObject, outFilter);
This will hopefully help someone since I spent a day doing this and almost gave up twice ;)
I have encoding problems with XMLFilter solution, so I made XMLStreamReader to ignore namespaces:
class XMLReaderWithoutNamespace extends StreamReaderDelegate {
public XMLReaderWithoutNamespace(XMLStreamReader reader) {
super(reader);
}
#Override
public String getAttributeNamespace(int arg0) {
return "";
}
#Override
public String getNamespaceURI() {
return "";
}
}
InputStream is = new FileInputStream(name);
XMLStreamReader xsr = XMLInputFactory.newFactory().createXMLStreamReader(is);
XMLReaderWithoutNamespace xr = new XMLReaderWithoutNamespace(xsr);
Unmarshaller um = jc.createUnmarshaller();
Object res = um.unmarshal(xr);
I believe you must add the namespace to your xml document, with, for example, the use of a SAX filter.
That means:
Define a ContentHandler interface with a new class which will intercept SAX events before JAXB can get them.
Define a XMLReader which will set the content handler
then link the two together:
public static Object unmarshallWithFilter(Unmarshaller unmarshaller,
java.io.File source) throws FileNotFoundException, JAXBException
{
FileReader fr = null;
try {
fr = new FileReader(source);
XMLReader reader = new NamespaceFilterXMLReader();
InputSource is = new InputSource(fr);
SAXSource ss = new SAXSource(reader, is);
return unmarshaller.unmarshal(ss);
} catch (SAXException e) {
//not technically a jaxb exception, but close enough
throw new JAXBException(e);
} catch (ParserConfigurationException e) {
//not technically a jaxb exception, but close enough
throw new JAXBException(e);
} finally {
FileUtil.close(fr); //replace with this some safe close method you have
}
}
In my situation, I have many namespaces and after some debug I find another solution just changing the NamespaceFitler class. For my situation (just unmarshall) this work fine.
import javax.xml.namespace.QName;
import org.xml.sax.Attributes;
import org.xml.sax.ContentHandler;
import org.xml.sax.SAXException;
import org.xml.sax.helpers.XMLFilterImpl;
import com.sun.xml.bind.v2.runtime.unmarshaller.SAXConnector;
public class NamespaceFilter extends XMLFilterImpl {
private SAXConnector saxConnector;
#Override
public void startElement(String uri, String localName, String qName, Attributes atts) throws SAXException {
if(saxConnector != null) {
Collection<QName> expected = saxConnector.getContext().getCurrentExpectedElements();
for(QName expectedQname : expected) {
if(localName.equals(expectedQname.getLocalPart())) {
super.startElement(expectedQname.getNamespaceURI(), localName, qName, atts);
return;
}
}
}
super.startElement(uri, localName, qName, atts);
}
#Override
public void setContentHandler(ContentHandler handler) {
super.setContentHandler(handler);
if(handler instanceof SAXConnector) {
saxConnector = (SAXConnector) handler;
}
}
}
Another way to add a default namespace to an XML Document before feeding it to JAXB is to use JDom:
Parse XML to a Document
Iterate through and set namespace on all Elements
Unmarshall using a JDOMSource
Like this:
public class XMLObjectFactory {
private static Namespace DEFAULT_NS = Namespace.getNamespace("http://tempuri.org/");
public static Object createObject(InputStream in) {
try {
SAXBuilder sb = new SAXBuilder(false);
Document doc = sb.build(in);
setNamespace(doc.getRootElement(), DEFAULT_NS, true);
Source src = new JDOMSource(doc);
JAXBContext context = JAXBContext.newInstance("org.tempuri");
Unmarshaller unmarshaller = context.createUnmarshaller();
JAXBElement root = unmarshaller.unmarshal(src);
return root.getValue();
} catch (Exception e) {
throw new RuntimeException("Failed to create Object", e);
}
}
private static void setNamespace(Element elem, Namespace ns, boolean recurse) {
elem.setNamespace(ns);
if (recurse) {
for (Object o : elem.getChildren()) {
setNamespace((Element) o, ns, recurse);
}
}
}
This is just a modification of lunicon's answer (https://stackoverflow.com/a/24387115/3519572) if you want to replace one namespace for another during parsing. And if you want to see what exactly is going on, just uncomment the output lines and set a breakpoint.
public class XMLReaderWithNamespaceCorrection extends StreamReaderDelegate {
private final String wrongNamespace;
private final String correctNamespace;
public XMLReaderWithNamespaceCorrection(XMLStreamReader reader, String wrongNamespace, String correctNamespace) {
super(reader);
this.wrongNamespace = wrongNamespace;
this.correctNamespace = correctNamespace;
}
#Override
public String getAttributeNamespace(int arg0) {
// System.out.println("--------------------------\n");
// System.out.println("arg0: " + arg0);
// System.out.println("getAttributeName: " + getAttributeName(arg0));
// System.out.println("super.getAttributeNamespace: " + super.getAttributeNamespace(arg0));
// System.out.println("getAttributeLocalName: " + getAttributeLocalName(arg0));
// System.out.println("getAttributeType: " + getAttributeType(arg0));
// System.out.println("getAttributeValue: " + getAttributeValue(arg0));
// System.out.println("getAttributeValue(correctNamespace, LN):"
// + getAttributeValue(correctNamespace, getAttributeLocalName(arg0)));
// System.out.println("getAttributeValue(wrongNamespace, LN):"
// + getAttributeValue(wrongNamespace, getAttributeLocalName(arg0)));
String origNamespace = super.getAttributeNamespace(arg0);
boolean replace = (((wrongNamespace == null) && (origNamespace == null))
|| ((wrongNamespace != null) && wrongNamespace.equals(origNamespace)));
return replace ? correctNamespace : origNamespace;
}
#Override
public String getNamespaceURI() {
// System.out.println("getNamespaceCount(): " + getNamespaceCount());
// for (int i = 0; i < getNamespaceCount(); i++) {
// System.out.println(i + ": " + getNamespacePrefix(i));
// }
//
// System.out.println("super.getNamespaceURI: " + super.getNamespaceURI());
String origNamespace = super.getNamespaceURI();
boolean replace = (((wrongNamespace == null) && (origNamespace == null))
|| ((wrongNamespace != null) && wrongNamespace.equals(origNamespace)));
return replace ? correctNamespace : origNamespace;
}
}
usage:
InputStream is = new FileInputStream(xmlFile);
XMLStreamReader xsr = XMLInputFactory.newFactory().createXMLStreamReader(is);
XMLReaderWithNamespaceCorrection xr =
new XMLReaderWithNamespaceCorrection(xsr, "http://wrong.namespace.uri", "http://correct.namespace.uri");
rootJaxbElem = (JAXBElement<SqgRootType>) um.unmarshal(xr);
handleSchemaError(rootJaxbElem, pmRes);