Question

When I call a remote method that returns a BigDecimal value via Spring’s Hessian functionality, it always returns zero.
Calling the method directly or using the plain Hessian servlet (non Spring) works normally.

What can be done to fix this?

Server side (Tomcat 7)

web.xml:

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee"
    xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"
    id="WebApp_ID" version="3.0">
    <servlet>
        <servlet-name>remoting</servlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
        <load-on-startup>1</load-on-startup>
    </servlet>

    <servlet-mapping>
        <servlet-name>remoting</servlet-name>
        <url-pattern>/remoting/*</url-pattern>
    </servlet-mapping>
</web-app>

remoting-servlet.xml:

<beans>
    <context:annotation-config />
    <context:component-scan base-package="hr.spi.logic.lcspi" />

    <tx:annotation-driven proxy-target-class="true" />

    <bean name="/lcspi/lc302/poslovi" class="org.springframework.remoting.caucho.HessianServiceExporter">
        <property name="service" ref="posloviLogic" />
        <property name="serviceInterface" value="hr.spi.logic.lcspi.lc302.PosloviLogicInterface" />
    </bean>
</beans>

Service class whose method I call:

package hr.spi.logic.lcspi.lc302;

@Transactional
@Repository
public class PosloviLogic implements PosloviLogicInterface {
    @Override
    public BigDecimal test()
    {
        BigDecimal bd = new BigDecimal("2.2"); 
        return bd;      
    }
}

Client side

Spring configuration – applicationContextHessian.xml:

<beans>
    <bean id="posloviLogic" class="org.springframework.remoting.caucho.HessianProxyFactoryBean">
        <property name="serviceUrl" value="http://localhost:8080/SpringWebTest/remoting/lcspi/lc302/poslovi" />
        <property name="serviceInterface" value="hr.spi.logic.lcspi.lc302.PosloviLogicInterface" />
    </bean>
</beans>

Console application test:

public static void main(String[] args) {
    ApplicationContext context = new ClassPathXmlApplicationContext("applicationContextHessian.xml");
    try {
        PosloviLogicInterface posloviLogic = (PosloviLogicInterface) context.getBean("posloviLogic");

        BigDecimal bd = posloviLogic.test();
        System.out.println(bd); // This returns 0.00

    } catch (Exception ex) {
        System.out.println(ex.getMessage());
    }
}

EDIT:
Libraries used were Spring 3.2 and Hessian 4.0.7

Answer 1

You could use HessianServlet.setSerializerFactory() to set your own SerializerFactory and return the com.caucho.hessian.io.BigDecimalDeserializer as Deserializer for BigDecimal.

We patched it like this and it works. No idea why it isn’t implemented this way.

See http://www.jarvana.com/jarvana/view/com/caucho/hessian/4.0.7/hessian-4.0.7-src.jar!/com/caucho/hessian/server/HessianServlet.java?format=ok