cxf+spring+数字签名开发webservice（二）

• 场景

        上一章中的webservice接口，因为现场正式环境的项目与外部单位网络不通，是通过前置机与外部进行数据交换，所以我们将webservice部署在前置机，在使用HttpURLConnection与正式服务器上进行数       据传递。这里可以使用的技术挺多的，如：java的rmi,Hessian,spring的HttpInvoker等，下面是使用HttpURLConnection的代码（实际情况是最后选择了spring的HttpInvoker）:

•  HttpURLConnection客户端调用方法 

package http.rpc.util;

import java.io.BufferedOutputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLEncoder;
import java.util.Map;

public class ClientUtils {
  /*
   * @param url    服务端url地址
   * @param beanid 访问远程方法所在的类名
   * @param method 调用服务端的方法名
   * @param param  服务端的方法的参数
   */
    public static Object remoteService(String url, String beanid, String method, String param) {
        HttpURLConnection urlcon = null;
        String result = null;
        try {
            if (param == null) {
                param = "";
            }
            URL u = new URL(url + "/webservice.rpc");

            byte[] databuffer = new byte[1024];
            ByteArrayOutputStream outStream = new ByteArrayOutputStream();
            int len = 0;
            try {
                urlcon = (HttpURLConnection) u.openConnection();
                urlcon.setDoOutput(true);
                urlcon.setRequestMethod("POST");
                OutputStream buf = new BufferedOutputStream(urlcon.getOutputStream());
                OutputStreamWriter out = new OutputStreamWriter(buf, "UTF-8");
                /* 向webservice.rpc传递3个参数 */
                out.write("serverid=" + beanid + "&method=" + method + param);
                out.flush();
                out.close();

                urlcon.connect();
                if (urlcon.getResponseCode() == 200) {
                    InputStream in = urlcon.getInputStream();
                    while ((len = in.read(databuffer)) != -1) {
                        outStream.write(databuffer, 0, len);
                    }
                    in.close();
                    result = new String(outStream.toByteArray(), "utf-8");
                    System.out.println(result);
                    urlcon.disconnect();
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
        } catch (MalformedURLException e) {
            e.printStackTrace();
        }
        urlcon.disconnect();
        return result;
    }
}

• 服务端web.xml配置(简单的servlet配置)

<servlet-mapping>
   <servlet-name>testserver</servlet-name>
   <url-pattern>/webservice.rpc</url-pattern>
</servlet-mapping>
  
<servlet>
   <servlet-name>testserver</servlet-name>
<servlet-class>http.rpc.Server</servlet-class>

• 服务端http请求类

package http.rpc;

import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

public class Server extends HttpServlet{

    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp)
            throws ServletException, IOException {
        System.out.println("doPost");
        String serverid = req.getParameter("serverid").toString();
        String method = req.getParameter("method").toString();
        String methodParam = req.getParameter("param").toString();
        ServletOutputStream sos = resp.getOutputStream();
        String result = "远程调用返回";
        sos.write(result.getBytes("utf-8"));
    }
}

• 最后说说

        Server类得到远程方法信息后，可以使用反射去调用具体方法。返回的数据如果是对象类型，可以实现序列化和反序列化进行数据传递。因为使用spring的HttpInvoker，就没写得很完善，这里只是做个记录，有时间再完善吧。