cxf的一些使用说明

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package org.apache.cxf.transport.servlet;



import java.io.IOException;

import java.io.InputStream;

import java.lang.reflect.Method;

import java.util.Collection;

import java.util.Enumeration;



import javax.servlet.ServletConfig;

import javax.servlet.ServletContext;

import javax.servlet.ServletException;



import org.apache.cxf.Bus;

import org.apache.cxf.BusFactory;

import org.apache.cxf.common.util.ReflectionUtil;

import org.apache.cxf.helpers.CastUtils;

import org.springframework.context.ApplicationContext;

import org.springframework.context.ApplicationListener;

import org.springframework.context.event.ContextRefreshedEvent;

import org.springframework.context.support.AbstractApplicationContext;

import org.springframework.core.io.Resource;

import org.springframework.web.context.support.WebApplicationContextUtils;

import org.springframework.web.context.support.XmlWebApplicationContext;



public class CXFServlet extends CXFNonSpringServlet

    implements ApplicationListener<ContextRefreshedEvent> {

    private static final long serialVersionUID = -5922443981969455305L;

    private boolean busCreated;

    private XmlWebApplicationContext createdContext; 

    

    public CXFServlet() {

    }



    @Override

    protected void loadBus(ServletConfig sc) {

        ApplicationContext wac = WebApplicationContextUtils.

            getWebApplicationContext(sc.getServletContext());

        

        if (wac instanceof AbstractApplicationContext) {

            addListener((AbstractApplicationContext)wac);

        }

        

        String configLocation = sc.getInitParameter("config-location");

        if (configLocation == null) {

            try {

                InputStream is = sc.getServletContext().getResourceAsStream("/WEB-INF/cxf-servlet.xml");

                if (is != null && is.available() > 0) {

                    is.close();

                    configLocation = "/WEB-INF/cxf-servlet.xml";

                }

            } catch (Exception ex) {

                //ignore

            }

        }

        if (configLocation != null) {

            wac = createSpringContext(wac, sc.getServletContext(), configLocation);

        }

        if (wac != null) {

            setBus((Bus)wac.getBean("cxf", Bus.class));

        } else {

            busCreated = true;

            setBus(BusFactory.newInstance().createBus());

        }

    }



    protected void addListener(AbstractApplicationContext wac) {

        try {

            //spring 2 vs spring 3 return type is different

            Method m = wac.getClass().getMethod("getApplicationListeners");

            Collection<Object> c = CastUtils.cast((Collection<?>)ReflectionUtil

                                                      .setAccessible(m).invoke(wac));

            c.add(this);

        } catch (Throwable t) {

            //ignore.

        }

    }



    /**

     * Try to create a spring application context from the config location.

     * Will first try to resolve the location using the servlet context.

     * If that does not work then the location is given as is to spring

     * 

     * @param ctx

     * @param sc

     * @param configLocation

     * @return

     */

    private ApplicationContext createSpringContext(ApplicationContext ctx,

                                                   final ServletContext sc,

                                                   String location) {

        XmlWebApplicationContext ctx2 = new XmlWebApplicationContext();

        createdContext = ctx2;

        ctx2.setServletConfig(new ServletConfig() {

            public String getServletName() {

                return "CXF";

            }

            public ServletContext getServletContext() {

                return sc;

            }

            public String getInitParameter(String name) {

                return sc.getInitParameter(name);

            }

            public Enumeration<String> getInitParameterNames() {

                return sc.getInitParameterNames();

            }

        });

        Resource r = ctx2.getResource(location);

        try {

            InputStream in = r.getInputStream();

            in.close();

        } catch (IOException e) {

            //ignore

            r = ctx2.getResource("classpath:" + location);

            try {

                r.getInputStream().close();

            } catch (IOException e2) {

                //ignore

                r = null;

            }

        }

        try {

            if (r != null) {

                location = r.getURL().toExternalForm();

            }

        } catch (IOException e) {

            //ignore

        }        

        if (ctx != null) {

            ctx2.setParent(ctx);

            String names[] = ctx.getBeanNamesForType(Bus.class);

            if (names == null || names.length == 0) {

                ctx2.setConfigLocations(new String[] {"classpath:/META-INF/cxf/cxf.xml",

                                                      location});                

            } else {

                ctx2.setConfigLocations(new String[] {location});                                

            }

        } else {

            ctx2.setConfigLocations(new String[] {"classpath:/META-INF/cxf/cxf.xml",

                                                  location});

            createdContext = ctx2;

        }

        ctx2.refresh();

        return ctx2;

    }

    public void destroyBus() {

        if (busCreated) {

            //if we created the Bus, we need to destroy it.  Otherwise, spring will handleit.

            getBus().shutdown(true);

            setBus(null);

        }

        if (createdContext != null) {

            createdContext.close();

        }

    }



    public void onApplicationEvent(ContextRefreshedEvent event) {

        destroy();

        setBus(null);

        try {

            init(getServletConfig());

        } catch (ServletException e) {

            throw new RuntimeException("Unable to reinitialize the CXFServlet", e);

        }

    }



}

View Code

如果存在Web-INF/cxf-servlet.xml,或者在web.xml中配置的cxf Servlet节按中提供了config-location，那么cxf会自己创建一个spring容器，如果在web.xml中同时也使用spring的监听器创建容器

 <context-param>

  <param-name>contextConfigLocation</param-name> 

  <param-value>classpath*:conf/cxf-servlet.xml</param-value> 

  </context-param> 

 <listener>

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

  </listener>

View Code

那么cxf容器会作为子容器，就是系统中有2个spring容器。
cxf自己创建容器时会加载classpath:/META-INF/cxf/cxf.xml这个就中的bug,如果系统只建立一个spring容器（Web-INF/下以及cxfServlet中不提供配置),那么需要自己在spring配置xml文件中通过资源导入classpath:/META-INF/cxf/cxf.xml 加载，或者将该配置放在web.xml的context-param 中