Java Programming

NB: Question was also asked two weeks ago on stackoverflow.com. Any solution will be shared there as well: https://stackoverflow.com/questions/43740866/unsupporteddatatypeexception-thrown-by-writetooutputstream-method-when-soap…

Environment: Java 8

Issue: When a javax.xml.soap.SOAPMessage instance includes an attachment (in this case, a GZipped archive file), writeTo(OutputStream) method throws the following exception:

javax.activation.UnsupportedDataTypeException: no object DCH for MIME type application/gzip

Is there a more robust and/or conventional way to build SOAPMessage instances with attachments?

Sample code for Error Replication:

import java.io.ByteArrayInputStream;

import java.io.ByteArrayOutputStream;

import java.io.File;

import java.io.FileOutputStream;

import java.io.IOException;

import java.io.OutputStreamWriter;

import java.nio.charset.Charset;

import java.nio.file.Files;

import java.util.zip.GZIPOutputStream;

import javax.xml.parsers.ParserConfigurationException;

import javax.xml.soap.AttachmentPart;

import javax.xml.soap.MessageFactory;

import javax.xml.soap.MimeHeaders;

import static javax.xml.soap.SOAPConstants.DEFAULT_SOAP_PROTOCOL;

import javax.xml.soap.SOAPException;

import javax.xml.soap.SOAPMessage;

import javax.xml.transform.TransformerException;

import org.xml.sax.SAXException;

public class SOAPMessageWriteToTest {

    private static final String FILE_NAME = "TestGZipFile.txt.gz";

    private static final String UNCOMPRESSED_CONTENTS

            = "Two households, both alike in dignity," + System.lineSeparator()

            + "In fair Verona, where we lay our scene," + System.lineSeparator()

            + "From ancient grudge break to new mutiny," + System.lineSeparator()

            + "Where civil blood makes civil hands unclean." + System.lineSeparator()

            + "From forth the fatal loins of these two foes" + System.lineSeparator()

            + "A pair of star-crossed lovers take their life," + System.lineSeparator()

            + "Whose misadventured piteous overthrows" + System.lineSeparator()

            + "Doth with their death bury their parents̓ strife." + System.lineSeparator()

            + "The fearful passage of their death-marked love" + System.lineSeparator()

            + "And the continuance of their parents̓ rage," + System.lineSeparator()

            + "Which but their children̓s end, naught could remove," + System.lineSeparator()

            + "Is now the two-hours̓traffic of our stage;" + System.lineSeparator()

            + "The which if you with patient ears attend," + System.lineSeparator()

            + "What here shall miss, our toil shall strive to mend." + System.lineSeparator()

            + "00101010111001000011011011110111001010010001001100110100111" + System.lineSeparator();

    private static final String SOAP_MESSAGE_XML

            = "<soapenv:Envelope "

            + "xmlns:soapenv=\"http://schemas.xmlsoap.org/soap/envelope/\">\n"

            + "   <soapenv:Header/>\n"

            + "   <soapenv:Body>\n"

            + "      <AResponse>\n"

            + "         <ResponseFile>" + FILE_NAME + "</ResponseFile>\n"

            + "      </AResponse>\n"

            + "   </soapenv:Body>\n"

            + "</soapenv:Envelope>";

    /*

     * MIME types to test

     */

    private static final String MIME_TYPE = "application/gzip";

    //private static final String MIME_TYPE = "application/octet-stream";

    public static void main(String[] args)

            throws IOException, ParserConfigurationException,

            SAXException, SOAPException, TransformerException {

        /*

         * Test case initialization

         */

        final File testGZipFile = new File(FILE_NAME);

        createFileIfMissing(testGZipFile);

        final SOAPMessage testSoapMessage = generateSoapMessage();

        attach(testSoapMessage, testGZipFile);

        /*

         * Error replication; will throw UnsupportedDataTypeException

         */

        final String result;

        try (ByteArrayOutputStream out = new ByteArrayOutputStream()) {

            testSoapMessage.writeTo(out);

            result = new String(out.toByteArray(), Charset.forName("UTF-8"));

        }

        System.out.println("result: " + result);

    }

    /*

     * If one doesn't exist, create a test GZip file for error replication.

     */

    private static void createFileIfMissing(final File testGZipFile)

            throws IOException {

        if (!testGZipFile.exists()) {

            try (FileOutputStream fos = new FileOutputStream(testGZipFile);

                    GZIPOutputStream gzos = new GZIPOutputStream(fos);

                    OutputStreamWriter osw = new OutputStreamWriter(gzos)) {

                osw.write(UNCOMPRESSED_CONTENTS);

            }

        }

    }

    /*

     * Build a SOAPMessage instance based on static XML. Will attach to it.

     */

    private static SOAPMessage generateSoapMessage()

            throws IOException, TransformerException, SOAPException {

        final SOAPMessage soapMessage;

        try (ByteArrayInputStream bais = new ByteArrayInputStream(SOAP_MESSAGE_XML.getBytes("UTF-8"))) {

            soapMessage = MessageFactory

                    .newInstance(DEFAULT_SOAP_PROTOCOL)

                    .createMessage(new MimeHeaders(), bais);

        }

        return soapMessage;

    }

    /*

     * Attach the File parameter to the SOAPMessage parameter. Leverages side effects. NAUGHTY!

     */

    private static void attach(SOAPMessage testSoapMessage, final File testGZipFile)

            throws IOException, SOAPException {

        final AttachmentPart attachmentPart = testSoapMessage.createAttachmentPart();

        final byte[] attachmentData = Files.readAllBytes(testGZipFile.toPath());

        testSoapMessage.addAttachmentPart(attachmentPart);

        try (ByteArrayInputStream bais = new ByteArrayInputStream(attachmentData)) {

            attachmentPart.setContent(bais, MIME_TYPE);

        }

        testSoapMessage.saveChanges();

    }

}