imageservlet.java~25~

使用JBulider开发的java实例。非常全。

package cmp2image;

import javax.servlet.*;
import javax.servlet.http.*;
import java.io.*;
import java.util.*;
import java.sql.*;
import javax.naming.*;
import javax.rmi.PortableRemoteObject;

public class ImageServlet
    extends HttpServlet {
  private CatalogHome catalogHome;

  public void init() throws ServletException {
  }

  //Process the HTTP Get request
  public void service(HttpServletRequest request, HttpServletResponse response) throws
      ServletException, IOException {
    Flower flower = null;
    HttpSession session = request.getSession(true);
    try {
      Context context = getInitialContext();

      //look up jndi name
      Object ref = context.lookup("Catalog");
      //look up jndi name and cast to Home interface
      catalogHome = (CatalogHome) PortableRemoteObject.narrow(ref, CatalogHome.class);

      Catalog catalog = catalogHome.create();
      String str = request.getParameter("pic");
      String name = str.trim();
      ArrayList collection = catalog.findOne(name);
      byte[] buf = null;
      Iterator i = collection.iterator();
      while (i.hasNext()) {
        Object obj = i.next();

        if (obj instanceof byte[]) {
          buf = (byte[]) obj;
        }
      }
      response.getOutputStream().write(buf);
      getServletContext().getRequestDispatcher("/display.jsp").include(request,
          response);

    }
    catch (Exception ex) {
      ex.printStackTrace();
    }

  }

  private Context getInitialContext() throws Exception {
    String url = "t3://localhost:7001";
    String user = null;
    String password = null;
    Properties properties = null;
    try {
      properties = new Properties();
      properties.put(Context.INITIAL_CONTEXT_FACTORY,
                     "weblogic.jndi.WLInitialContextFactory");
      properties.put(Context.PROVIDER_URL, url);
      if (user != null) {
        properties.put(Context.SECURITY_PRINCIPAL, user);
        properties.put(Context.SECURITY_CREDENTIALS,
                       password == null ? "" : password);
      }

      return new InitialContext(properties);
    }
    catch (Exception e) {
      System.out.println("Unable to connect to WebLogic server at " + url);
      System.out.println("Please make sure that the server is running.");
      throw e;
    }
  }

  //Clean up resources
  public void destroy() {
  }
}