HttpInvoker without web container?

[aaime]

I'm wondering, is it possible to embed httpinvoker in a standalone application without using a web container such as tomcat? If I'm exposing just web services and I want the application to stay in the background (windows service) and use as little memory as possibile, would it be possible to embed servlet support?
Do you have any experience on this? Can you point to some library that can be used to embed an httpinvoker like described?

[robh]

HTTP Invoker is designed to site behind the Spring servlet infrastructure so you can't really use it without that in place. HTTP Invoker relies on the infrastructure provided by the servlet container for HTTP communication. You might want to look at Jetty for a small, embeddable servlet container to solve this problem.

Rob

[murrayd]

I have successfully implemented a standalone Java server using the HTTPinvoker running in an embedded Jetty instance. I can post up the code if you are interested.

Regards,
Dave

[aaime]

I have successfully implemented a standalone Java server using the HTTPinvoker running in an embedded Jetty instance. I can post up the code if you are interested.

Regards,
Dave

Well, yes, it would be interesting.... maybe only a short document with the most important steps...

[mark_in_gr]

I am having problems w/ConnectExceptions when testing an HttpInvoker process using embedded Jetty. I have a client Swing app and a Spring Config file, which is attempting to access and define a remote bean by way of HttpInvokerProxyFactoryBean. On the other end(The data access service), I
have another Spring Config file which exposes the remote beans by way of HttpInvokerServiceExporter.

I took the following approach to setting up the Jetty, web and Spring config files, separating Jetty from Spring:

http://jroller.com/page/sjivan?entry...ty_in_a_spring

I suspect the problem is either in the Jetty.xml or web.xml files.

The Jetty.xml is here:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE beans PUBLIC "-//SPRING//DTD BEAN//EN" "http://www.springframework.org/dtd/spring-beans.dtd">

<beans>
    <bean id="Server"
          class="org.mortbay.jetty.Server" init-method="start" destroy-method="stop">
        <property name="connectors">
            <list>
                <bean id="Connector" class="org.mortbay.jetty.nio.SelectChannelConnector">
                    <property name="port" value="8080"/>
                </bean>
            </list>
        </property>

        <property name="handler">
            <bean id="handlers"
                  class="org.mortbay.jetty.handler.HandlerCollection">
                <property name="handlers">
                    <list>
                        <bean id="contexts"
                              class="org.mortbay.jetty.handler.ContextHandlerCollection">
                            <property name="handlers">
                                <list>
                                    <bean class="org.mortbay.jetty.webapp.WebAppContext">
                                        <property name="contextPath" value="/"/>
                                        <!--<property name="war" value="../web">-->
                                            <property name="resourceBase" value="web">
                                        </property>
                                    </bean>
                                </list>
                            </property>
                        </bean>
                    </list>
                </property>
            </bean>
        </property>
    </bean>
</beans>

The web.xml file is here:

<?xml version="1.0" encoding="ISO-8859-1"?>
<!DOCTYPE web-app PUBLIC "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN" "http://java.sun.com/dtd/web-app_2_3.dtd">
<web-app>

    <display-name>Backcheck Remoting</display-name>
    <description>Backcheck Remoting Services</description>

    <context-param>
        <param-name>contextConfigLocation</param-name>
        <param-value>
            classpath:SpringConfig.xml
        </param-value>
    </context-param>

    <listener>
        <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
    </listener>

    <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>

The client Spring Config is here:

<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:aop="http://www.springframework.org/schema/aop"
       xmlns:tx="http://www.springframework.org/schema/tx"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.0.xsd
       http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-2.0.xsd
http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-2.0.xsd">  
          
    <bean id="httpGroupDao" class="org.springframework.remoting.httpinvoker.HttpInvokerProxyFactoryBean">
      <property name="serviceUrl" value="http://localhost:8080/remoting/httpGroupDao"/>
      <property name="serviceInterface" value="com.xrite.ind.backcheck.dao.group.GroupDao"/>
      <property name="httpInvokerRequestExecutor">
	<bean class="org.springframework.remoting.httpinvoker.CommonsHttpInvokerRequestExecutor"/>
      </property>
    </bean>
    
    
</beans>

The code to access the remote bean from the Swing Client is:

private static BeanFactory beanFactory;
beanFactory = new ClassPathXmlApplicationContext("SpringClientConfig.xml");
return (GroupDao) beanFactory.getBean("httpGroupDao");

The Data Access Layer/Server Spring Config file is:

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:aop="http://www.springframework.org/schema/aop"
       xmlns:tx="http://www.springframework.org/schema/tx"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.0.xsd
       http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-2.0.xsd
http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-2.0.xsd">

<bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close">
        <property name="driverClassName" value="com.mysql.jdbc.Driver"/>
        <property name="url" value="jdbc:mysql://localhost:3306/backcheck"/>
        <property name="username" value="root"/>
        <property name="password" value="goteam"/>
    </bean>
    
    <bean id="sessionFactory" class="org.springframework.orm.hibernate3.LocalSessionFactoryBean">
        <property name="dataSource" ref="dataSource"/>    
        <property name="mappingResources">
            <list>
                <value>Color.hbm.xml</value>
                <value>ReflectanceData.hbm.xml</value>
                <value>Group.hbm.xml</value>
                <value>Standard.hbm.xml</value>
                <value>Sample.hbm.xml</value>
                <value>Lab.hbm.xml</value> 
                <value>Tag.hbm.xml</value>
                <value>TagCategory.hbm.xml</value>
                <value>Tolerance.hbm.xml</value>
                <value>ViewSet.hbm.xml</value>
                <value>ViewSetItem.hbm.xml</value>
                <value>FilterState.hbm.xml</value>
                <value>User.hbm.xml</value>
                <value>FilterSort.hbm.xml</value>
            </list>
        </property>
        <property name="hibernateProperties">
            <props>
                <prop key="hibernate.dialect">org.hibernate.dialect.MySQLDialect</prop>
                <prop key="hibernate.show_sql">false</prop>
                <prop key="hibernate.hbm2ddl.auto">update</prop>
                <prop key="current_session_context_class">thread</prop>
                <prop key="transaction.factory_class">org.hibernate.transaction.JDBCTransactionFactory</prop>
            </props>
        </property>
    </bean>
    
    <bean id="transactionManager"
          class="org.springframework.orm.hibernate3.HibernateTransactionManager">
        <property name="sessionFactory">
            <ref bean="sessionFactory"/>
        </property>
    </bean> 
    
    <bean id="groupDao"
          class="com.xrite.ind.backcheck.dao.group.GroupDAOImpl">
        <property name="sessionFactory" ref="backcheckSessionFactory"/>
    </bean>

    <bean name="/httpGroupDao" class="org.springframework.remoting.httpinvoker.HttpInvokerServiceExporter">
      <property name="service" ref="groupDao"/>
      <property name="serviceInterface" value="com.xrite.ind.backcheck.dao.group.GroupDao"/>      
    </bean>

  </beans>

[mark_in_gr]

Ok, I added the SimpleUrlHandlerMapping settings to my spring config on the server end, but still getting the same errors.

Question . . . in Sanjiv Jivan's blog explaining how to embed Jetty in Spring, he mentions that using FileSystemXmlApplicationContext ctx = new FileSystemXmlApplicationContext(path/to/jetty.xml) to load the jetty.xml is the way to go. This, in combination w/the web.xml Spring ContextLoaderListener load applicationContext.xml, sounds like it should do the trick. However, how does the Jetty server itself get started?

What is the most straightforward approach to tying the web.xml, jetty.xml and springapplicationcontext.xml files together?

[mark_in_gr]

Some progress made . . . I have jetty running now based on the org.mortbay.jetty.Server bean in jetty.xml. Now getting 404s, but that may be due to a web context issue.

[mark_in_gr]

Still getting 404 errors upon each URL request. Not sure where the problem is, but suspect either the web.xml or something missing in either the client Spring App Context config or Server Spring App Context config.

Latest web.xml

<web-app>

    <display-name>Backcheck Remoting</display-name>
    <description>Backcheck Remoting Services</description>

    <context-param>
        <param-name>contextConfigLocation</param-name>
        <param-value>
            classpath:SpringConfig.xml
        </param-value>
    </context-param>

    <listener>
        <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
    </listener>

    <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>-->
        <url-pattern>/http*</url-pattern>
    </servlet-mapping>
    
</web-app>

Latest client spring config:

<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:aop="http://www.springframework.org/schema/aop"
       xmlns:tx="http://www.springframework.org/schema/tx"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.0.xsd
       http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-2.0.xsd
http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-2.0.xsd">    
            
    <bean id="groupDao" class="org.springframework.remoting.httpinvoker.HttpInvokerProxyFactoryBean">
      <property name="serviceUrl" value="http://localhost:8080/httpGroupDao"/>
      <property name="serviceInterface" value="com.xrite.ind.backcheck.dao.group.GroupDao"/>
      <property name="httpInvokerRequestExecutor">
	<bean class="org.springframework.remoting.httpinvoker.CommonsHttpInvokerRequestExecutor"/>
      </property>
    </bean>
        
</beans>

Latest server Spring config:

<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:aop="http://www.springframework.org/schema/aop"
       xmlns:tx="http://www.springframework.org/schema/tx"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.0.xsd
       http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-2.0.xsd
http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-2.0.xsd">    
    
    <bean id="backcheckDataSource" class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close">
        <property name="driverClassName" value="com.mysql.jdbc.Driver"/>
        <property name="url" value="jdbc:mysql://localhost:3306/backcheck"/>
        <property name="username" value="root"/>
        <property name="password" value="goteam"/>
    </bean>
    
    <bean id="backcheckSessionFactory" class="org.springframework.orm.hibernate3.LocalSessionFactoryBean">
        <property name="dataSource" ref="backcheckDataSource"/>    
        <property name="mappingResources">
            <list>
                <value>Color.hbm.xml</value>
                <value>ReflectanceData.hbm.xml</value>
                <value>Group.hbm.xml</value>
                <value>Standard.hbm.xml</value>
                <value>Sample.hbm.xml</value>
                <value>Lab.hbm.xml</value> 
                <value>Tag.hbm.xml</value>
                <value>TagCategory.hbm.xml</value>
                <value>Tolerance.hbm.xml</value>
                <value>ViewSet.hbm.xml</value>
                <value>ViewSetItem.hbm.xml</value>
                <value>FilterState.hbm.xml</value>
                <value>User.hbm.xml</value>
                <value>FilterSort.hbm.xml</value>
            </list>
        </property>
        <property name="hibernateProperties">
            <props>
                <prop key="hibernate.dialect">org.hibernate.dialect.MySQLDialect</prop>
                <prop key="hibernate.show_sql">false</prop>
                <prop key="hibernate.hbm2ddl.auto">update</prop>
                <prop key="current_session_context_class">thread</prop>
                <prop key="transaction.factory_class">org.hibernate.transaction.JDBCTransactionFactory</prop>
            </props>
        </property>
    </bean>
    
    <bean id="backcheckTransactionManager"
          class="org.springframework.orm.hibernate3.HibernateTransactionManager">
        <property name="sessionFactory">
            <ref bean="backcheckSessionFactory"/>
        </property>
    </bean> 
    
    <bean id="groupDao"
          class="com.xrite.ind.backcheck.dao.group.GroupDAOImpl">
        <property name="sessionFactory" ref="backcheckSessionFactory"/>
    </bean>

    <bean name="/httpGroupDao" class="org.springframework.remoting.httpinvoker.HttpInvokerServiceExporter">
      <property name="service" ref="groupDao"/>
      <property name="serviceInterface" value="com.xrite.ind.backcheck.dao.group.GroupDao"/>      
    </bean>

latest jetty.xml

<beans>
    <bean id="Server"
          class="org.mortbay.jetty.Server" init-method="start" destroy-method="stop">
        <property name="connectors">
            <list>
                <bean id="Connector" class="org.mortbay.jetty.nio.SelectChannelConnector">
                    <property name="port" value="8080"/>
                </bean>
            </list>
        </property>

        <property name="handler">
            <bean id="handlers"
                  class="org.mortbay.jetty.handler.HandlerCollection">
                <property name="handlers">
                    <list>
                        <bean id="contexts"
                              class="org.mortbay.jetty.handler.ContextHandlerCollection">
                            <property name="handlers">
                                <list>
                                    <bean class="org.mortbay.jetty.webapp.WebAppContext">
                                        <property name="contextPath" value="/"/>
                                        <!--<property name="war" value="../web">-->
                                            <property name="resourceBase" value="web">
                                        </property>
                                    </bean>
                                </list>
                            </property>
                        </bean>
                    </list>
                </property>
            </bean>
        </property>
    </bean>
</beans>

This is based on the examples in the Spring 2.0.2 Remoting/HttpInvoker section of the Docs.

[mark_in_gr]

Does anyone have another example of setting up a complete HttpInvoker example other than what is found in the Spring docs or Spring in action. I have followed those examples, and cannot figure out why I keep getting the 404 errors.

[karldmoore]

I'm guessing your problem might be to do with the serviceURL.

<property name="serviceUrl" value="http://localhost:8080/httpGroupDao"/>

If your exposed service is called groupDao, the servlet name is remoting and the webapp is called test......

<property name="serviceUrl" value="http://localhost:8080/test/remoting/groupDao"/>