Why is this simple SOAP client not working (org.apache.http)?

Question

I want to send an XML file as a request to a SOAP server. Here is the code I have: (modified from Sending HTTP Post request with SOAP action using org.apache.http )

import org.apache.http.client.*;
import org.apache.http.client.methods.*;
import org.apache.http.impl.client.*;
import org.apache.http.entity.StringEntity;
import org.apache.http.protocol.HTTP;
import org.apache.http.HttpResponse;
import java.net.URI;

public static void req()   {
        try {
            HttpClient httpclient = new DefaultHttpClient();
            String body="xml here";
            String bodyLength=new Integer(body.length()).toString();

            URI uri=new URI("http://1.1.1.1:100/Service");
            HttpPost httpPost = new HttpPost(uri);
            httpPost.setHeader( "SOAPAction", "MonitoringService" );
            httpPost.setHeader("Content-Type", "text/xml;charset=UTF-8");


            StringEntity entity = new StringEntity(body, "text/xml",HTTP.DEFAULT_CONTENT_CHARSET);
            httpPost.setEntity(entity);

            RequestWrapper requestWrapper=new RequestWrapper(httpPost);
            requestWrapper.setMethod("POST");


            requestWrapper.setHeader("Content-Length",bodyLength);
            HttpResponse response = httpclient.execute(requestWrapper);
            System.out.println(response);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

Before this I was getting error 'http 500' (internal server error) from the server , but now Im not getting any reply at all. I know that the server works right because with other clients there is no problem.

Thanks.

Answer 1

org.apache.http API is not SOAP/web service aware and so you're doing the tricky work in a non-standard way. The code is not very java-friendly or flexible, because it can't automatically "bind" (convert) java object data into the SOAP request and out of the SOAP response. It's a little lengthy, tricky to debug and get working, and brittle - are you handling the full SOAP protocol, including fault handling, etc?.

Can I suggest using JAX-WS standard, which is built into the JVM:

1. Save the WSDL file to local disk
E.g. <app path>/META-INF/wsdl/abc.com/calculator/Calculator.wsdl
If you don't have the WSDL, you can type into browser & save result page to disk:
http://abc.com/calculator/Calculator?wsdl

2. Use wsimport command to convert WSDL to java class files
For JDK, tool is in <jdkdir>\bin\wsimport.exe (or .sh).
For an app server, will be something like <app_server_root>\bin\wsimport.exe (or .sh)

<filepath>\wsimport -keep -verbose <wsdlpath>\Calculator.wsdl

OR if your WSDL is available via a pre-existing webservice

<filepath>\wsimport -keep -verbose http://abc.com/calculator/Calculator?wsdl

(you can also include "-p com.abc.calculator" to set the package of generated classes)

Files like the following are generated - include these source files in your java project:

com\abc\calculator\ObjectFactory.java       
com\abc\calculator\package-info.java       
com\abc\calculator\Calculator.java       ............................name = `<wsdl:portType>` name attribute      
com\abc\calculator\CalculatorService.java     ................name = `<wsdl:service>` name attribute    
com\abc\calculator\CalculatorRequestType.java  .......name = schema type used in input message    
com\abc\calculator\CalculatorResultType.java ..........name = schema type used in output message

2. Create a JAX-WS SOAP web service client

package com.abc.calculator.client;

import javax.xml.ws.WebServiceRef;
import com.abc.calculator.CalculatorService;
import com.abc.calculator.Calculator;

public class CalculatorClient {

    @WebServiceRef(wsdlLocation="META-INF/wsdl/abc.com/calculator/Calculator.wsdl")
    // or @WebServiceRef(wsdlLocation="http://abc.com/calculator/Calculator?wsdl")
    public static CalculatorService calculatorService;

    public CalculatorResponseType testCalculation() {
        try {
            CalculatorRequestType request = new CalculatorRequest();
            request.setSomeParameter("abc");
            request.setOtherParameter(3);
            Calculator calculator = calculatorService.getCalculatorPort();
            // automatically generate SOAP XML message, send via HTTP, 
            // receive & marshal response to java object 
            String response = calculator.doCalculation(response);
        } catch(Exception e) {
            e.printStackTrace();
        }
    }
}