请教:下面这段程序为什么编译不过去?

[snowredfox]

import java.io.* ;
import java.util.* ;
import javax.mail.* ;
import javax.mail.internet.* ;
import javax.activation.* ;

public class Mail {

Session session = null ;
String host = "xxx.xxx.xxx" ;
String username = "xxx" ;
String password = "xxxxx" ;
String defaultFrom = null ;
String store = null ;

void Fetch() {

Properties properties = System.getProperties() ;
properties.put("mail.transport.protocol", "stmp") ;
properties.put("mail.smtp.host", "xxx.xxx.xxx") ;
session = Session.getInstance(properties, null) ;

Store store = session.getStore("pop3") ;
store.connect(host, username, password) ;
Folder inbox = store.getDefaultFolder().getFolder("INBOX") ;
inbox.open(Folder.READ_WRITE) ;
Message message[] = inbox.getMessages() ;

for (int i=0,n=message.length;i<n;i++) {
System.out.println(i + ": " + message[i].getFrom()[0]
+ "\t" + message[i].getSubject()) ;
// message[i].writeTo(System.out) ;
// message[i].setFlag(Flags.Flag.SEEN, true) ;
}

inbox.close(true) ;
store.close() ;
}

public static void main(String[] args)
throws Exception {

Mail mail = new Mail() ;
mail.Fetch() ;
}
}

[BugHunterPro]

出错提示也不贴出来

[snowredfox]

Mail.java:26: 未报告的异常 javax.mail.NoSuchProviderException:必须被捕获或者被声明抛出 Store store = session.getStore("pop3") ;

还有9条类似的错误!~~~

[headstream]

把Store store = session.getStore("pop3") ;
放到try中。

[snowredfox]

to headstream:
为什么要如此呢?!~~
这里为什么会编译不过去,从逻辑上来看是没有问题的啊?!~~

[huangkai]

参看java异常处理的规则！

[snowredfox]

程序如果如下,则能正常的运行:

import java.io.* ;
import java.util.* ;
import javax.mail.* ;
import javax.mail.internet.* ;
import javax.activation.* ;

public class Mail {

public static void main(String[] args)
throws Exception {

Session session = null ;
String host = "xxx.xxx.xxx" ;
String username = "xxx" ;
String password = "xxxxx" ;
String defaultFrom = null ;
String store = null ;

Properties properties = System.getProperties() ;
properties.put("mail.transport.protocol", "stmp") ;
properties.put("mail.smtp.host", "xxx.xxx.xxx") ;
session = Session.getInstance(properties, null) ;

Store store = session.getStore("pop3") ;
store.connect(host, username, password) ;
Folder inbox = store.getDefaultFolder().getFolder("INBOX") ;
inbox.open(Folder.READ_WRITE) ;
Message message[] = inbox.getMessages() ;

for (int i=0,n=message.length;i<n;i++) {
System.out.println(i + ": " + message[i].getFrom()[0]
+ "\t" + message[i].getSubject()) ;
// message[i].writeTo(System.out) ;
// message[i].setFlag(Flags.Flag.SEEN, true) ;
}

inbox.close(true) ;
store.close() ;

}

[snowredfox]

void Fetch() throws MessagingException就OK啦...