使用javamail发送完邮件后怎样在程序中做一些清理工作？

Question

下面是错误信息
java.lang.SecurityException: Access to default session denied
at javax.mail.Session.getDefaultInstance(Session.java:175)
at mailsentservlet.doPost(mailsentservlet.java:136)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:760)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:247)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:256)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:643)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:480)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:995)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:643)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:494)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:641)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:480)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:995)
at org.apache.catalina.core.StandardContext.invoke(StandardContext.java:2415)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:180)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:643)
at org.apache.catalina.valves.ErrorDispatcherValve.invoke(ErrorDispatcherValve.java:171)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:641)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:172)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:641)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:480)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:995)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:174)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:643)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:480)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:995)
at org.apache.coyote.tomcat4.CoyoteAdapter.service(CoyoteAdapter.java:223)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:594)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.processConnection(Http11Protocol.java:392)
at org.apache.tomcat.util.net.TcpWorkerThread.runIt(PoolTcpEndpoint.java:565)
at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:619)
at java.lang.Thread.run(Thread.java:536)

Answer 1

import javax.mail.internet.*;  /** 
 * @author Bromon 
 */ 
 public class SenderWithSMTPVer 
 { 
 String host=""; 
 String user=""; 
 String password="";  public void setHost(String host) 
 { 
  this.host=host; 
 }  public void setAccount(
 String user,String password) 
 { 
  this.user=user; 
  this.password=password; 
 }  public void send(String from,String to, String subject,String content) 
 { 
  Properties props = new Properties(); 
  props.put("mail.smtp.host", host);
  //指定SMTP服务器 
  props.put("mail.smtp.auth", "true");
  //指定是否需要SMTP验证 
  try 
  { 
   Session mailSession = Session.getDefaultInstance(props); 
    
   mailSession.setDebug(true);
   //是否在控制台显示debug信息 
    
   Message message=new MimeMessage(mailSession); 
   message.setFrom(new InternetAddress(from));
  // //发件人 
   message.addRecipient(Message.RecipientType.TO,
   new InternetAddress(to));
  // //收件人 
    
   message.setSubject(subject);
   //邮件主题 
   message.setText(content);
   //邮件内容 
   message.saveChanges(); 
    
   Transport transport = mailSession.getTransport("smtp"); 
   transport.connect(host, user, password); 
   transport.sendMessage(message, message.getAllRecipients()); 
   transport.close(); 
  }catch(Exception e) 
  { 
   System.out.println(e); 
  } 
   
 }  public static void main(String args[]) 
 { 
  SenderWithSMTPVer sm=new SenderWithSMTPVer();   String content ;
  content = "";
  sm.setHost("smtp.163.com");
  //指定要使用的邮件服务器 
  sm.setAccount("","");
  //指定帐号和密码   /* 
 * @param String 发件人的地址 
   * @param String 收件人地址 
   * @param String 邮件标题 
   * @param String 邮件正文 
  */ 
  sm.send("","","test",content); 
 }  }上面是发邮件的源代码 我不知道你怎么写的
transport.close(); 应该是做清理工作的吧