gistfile1.java

import org.apache.commons.httpclient.HttpClient;
import org.apache.commons.httpclient.HttpStatus;
import org.apache.commons.httpclient.cookie.CookiePolicy;
import org.apache.commons.httpclient.methods.PostMethod;
import org.apache.commons.httpclient.methods.multipart.*;
import org.apache.commons.httpclient.params.HttpMethodParams;
import org.mule.api.MuleEventContext;
import org.mule.api.MuleMessage;
import org.mule.api.lifecycle.Callable;
import org.mule.util.IOUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.ByteArrayInputStream;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;

public class MultiPartFormDispatcher implements Callable {

    protected final transient Logger logger = LoggerFactory.getLogger(getClass());

    public Object onCall(MuleEventContext eventContext) throws Exception {

        PostMethod postMethod;
        HttpClient client;
        postMethod = new PostMethod("FOO");
        postMethod.getParams().setBooleanParameter(HttpMethodParams.USE_EXPECT_CONTINUE,
                true);

        List<ByteArrayPartSource> attachments = new ArrayList<ByteArrayPartSource>();
        List<String> attachmentContentTypes = new ArrayList<String>();        

        MuleMessage message = eventContext.getMessage();

        for (String attachment : message.getOutboundAttachmentNames()) {

            ByteArrayInputStream inputStream = (ByteArrayInputStream) message.getOutboundAttachment(attachment)
                    .getInputStream();
            attachments.add(new ByteArrayPartSource(attachment, IOUtils.toByteArray(inputStream)));
            attachmentContentTypes.add(message.getOutboundAttachment(attachment).getContentType());
        }

        @SuppressWarnings({"unchecked"})
        Map<String,String> postParameterMap = (Map<String,String>) message.getPayload();

        Part[] parts = new Part[postParameterMap.size() + attachments.size()];

        int i = 0;
        for (String  parameter : postParameterMap.keySet()) {
            parts[i] = new StringPart(parameter,postParameterMap.get(parameter));
            i++;
        }

        for (ByteArrayPartSource attachment : attachments) {
            parts[i] = new FilePart("inputFile",attachment,attachmentContentTypes.get(i),"UTF-8");
        }

        postMethod.setRequestEntity(
                new MultipartRequestEntity(parts, postMethod.getParams())
        );

        client = new HttpClient();
        client.getHttpConnectionManager().getParams().setConnectionTimeout(5000);

        postMethod.getParams().setCookiePolicy(CookiePolicy.IGNORE_COOKIES);
        postMethod.setRequestHeader("Cookie", "JSESSIONID=" + message.getSessionProperty("JSESSIONID"));

        int status = client.executeMethod(postMethod);
        if (status == HttpStatus.SC_OK) {
            logger.debug("Upload success");
        } else {
            throw new RuntimeException("Upload failed: " + HttpStatus.getStatusText(status));
        }

        message.setPayload(new String(postMethod.getResponseBody()));

        return message;

    }
}