我尝试从电子邮件中下载附件时有以下代码，我有下一个错误“无法连接到邮件存储”。任何人，任何帮助？
* ERROR
运行：
javax.mail.MessagingException: Connect failed;
nested exception is:
javax.net.ssl.SSLHandshakeException: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
at com.sun.mail.pop3.POP3Store.protocolConnect(POP3Store.java:148)
at javax.mail.Service.connect(Service.java:275)
at javax.mail.Service.connect(Service.java:156)
at javax.mail.Service.connect(Service.java:176)
at net.mail.EmailAttachmentReceiver.downloadEmailAttachments(EmailAttachmentReceiver.java:69)
at net.mail.EmailAttachmentReceiver.main(EmailAttachmentReceiver.java:155)
Caused by: javax.net.ssl.SSLHandshakeException: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
at sun.security.ssl.Alerts.getSSLException(Alerts.java:192)
at sun.security.ssl.SSLSocketImpl.fatal(SSLSocketImpl.java:1884)
at sun.security.ssl.Handshaker.fatalSE(Handshaker.java:276)
at sun.security.ssl.Handshaker.fatalSE(Handshaker.java:270)
at sun.security.ssl.ClientHandshaker.serverCertificate(ClientHandshaker.java:1341)
at sun.security.ssl.ClientHandshaker.processMessage(ClientHandshaker.java:153)
at sun.security.ssl.Handshaker.processLoop(Handshaker.java:868)
at sun.security.ssl.Handshaker.process_record(Handshaker.java:804)
at sun.security.ssl.SSLSocketImpl.readRecord(SSLSocketImpl.java:1016)
at sun.security.ssl.SSLSocketImpl.performInitialHandshake(SSLSocketImpl.java:1312)
at sun.security.ssl.SSLSocketImpl.readDataRecord(SSLSocketImpl.java:882)
at sun.security.ssl.AppInputStream.read(AppInputStream.java:102)
at java.io.BufferedInputStream.fill(BufferedInputStream.java:235)
at java.io.BufferedInputStream.read(BufferedInputStream.java:254)
at java.io.DataInputStream.readLine(DataInputStream.java:513)
at com.sun.mail.pop3.Protocol.simpleCommand(Protocol.java:347)
at com.sun.mail.pop3.Protocol.<init>(Protocol.java:91)
at com.sun.mail.pop3.POP3Store.getPort(POP3Store.java:201)
at com.sun.mail.pop3.POP3Store.protocolConnect(POP3Store.java:144)
... 5 more
Caused by: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
at sun.security.validator.PKIXValidator.doBuild(PKIXValidator.java:385)
at sun.security.validator.PKIXValidator.engineValidate(PKIXValidator.java:292)
at sun.security.validator.Validator.validate(Validator.java:260)
at sun.security.ssl.X509TrustManagerImpl.validate(X509TrustManagerImpl.java:326)
at sun.security.ssl.X509TrustManagerImpl.checkTrusted(X509TrustManagerImpl.java:231)
at sun.security.ssl.X509TrustManagerImpl.checkServerTrusted(X509TrustManagerImpl.java:126)
at sun.security.ssl.ClientHandshaker.serverCertificate(ClientHandshaker.java:1323)
... 19 more
Caused by: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
at sun.security.provider.certpath.SunCertPathBuilder.engineBuild(SunCertPathBuilder.java:196)
at java.security.cert.CertPathBuilder.build(CertPathBuilder.java:268)
at sun.security.validator.PKIXValidator.doBuild(PKIXValidator.java:380)
... 25 more
Could not connect to the message store
BUILD SUCCESSFUL (total time: 1 second)
* CODE
/*
* To change this license header, choose License Headers in Project Properties.
* To change this template file, choose Tools | Templates
* and open the template in the editor.
*/
package net.mail;
import java.io.File;
import java.io.IOException;
import java.util.Properties;
import javax.mail.Address;
import javax.mail.Folder;
import javax.mail.Message;
import javax.mail.MessagingException;
import javax.mail.Multipart;
import javax.mail.NoSuchProviderException;
import javax.mail.Part;
import javax.mail.Session;
import javax.mail.Store;
import javax.mail.internet.MimeBodyPart;
public class EmailAttachmentReceiver {
private String saveDirectory;
/**
* Sets the directory where attached files will be stored.
* @param dir absolute path of the directory
*/
public void setSaveDirectory(String dir) {
this.saveDirectory = dir;
}
/**
* Downloads new messages and saves attachments to disk if any.
* @param host
* @param port
* @param userName
* @param password
*/
public void downloadEmailAttachments(String host, String port,
String userName, String password) {
Properties properties = new Properties();
// server setting
properties.put("mail.pop3.host", host);
properties.put("mail.pop3.port", port);
// SSL setting
properties.setProperty("mail.pop3.socketFactory.class",
"javax.net.ssl.SSLSocketFactory");
properties.setProperty("mail.pop3.socketFactory.fallback", "false");
properties.setProperty("mail.pop3.socketFactory.port",
String.valueOf(port));
Session session = Session.getDefaultInstance(properties);
try {
// connects to the message store
Store store = session.getStore("pop3");
store.connect(userName, password);
// opens the inbox folder
Folder folderInbox = store.getFolder("INBOX");
folderInbox.open(Folder.READ_ONLY);
// fetches new messages from server
Message[] arrayMessages = folderInbox.getMessages();
for (int i = 0; i < arrayMessages.length; i++) {
Message message = arrayMessages[i];
Address[] fromAddress = message.getFrom();
String from = fromAddress[0].toString();
String subject = message.getSubject();
String sentDate = message.getSentDate().toString();
String contentType = message.getContentType();
String messageContent = "";
// store attachment file name, separated by comma
String attachFiles = "";
if (contentType.contains("multipart")) {
// content may contain attachments
Multipart multiPart = (Multipart) message.getContent();
int numberOfParts = multiPart.getCount();
for (int partCount = 0; partCount < numberOfParts; partCount++) {
MimeBodyPart part = (MimeBodyPart) multiPart.getBodyPart(partCount);
if (Part.ATTACHMENT.equalsIgnoreCase(part.getDisposition())) {
// this part is attachment
String fileName = part.getFileName();
attachFiles += fileName + ", ";
part.saveFile(saveDirectory + File.separator + fileName);
} else {
// this part may be the message content
messageContent = part.getContent().toString();
}
}
if (attachFiles.length() > 1) {
attachFiles = attachFiles.substring(0, attachFiles.length() - 2);
}
} else if (contentType.contains("text/plain")
|| contentType.contains("text/html")) {
Object content = message.getContent();
if (content != null) {
messageContent = content.toString();
}
}
// print out details of each message
System.out.println("Message #" + (i + 1) + ":");
System.out.println("\t From: " + from);
System.out.println("\t Subject: " + subject);
System.out.println("\t Sent Date: " + sentDate);
System.out.println("\t Message: " + messageContent);
System.out.println("\t Attachments: " + attachFiles);
}
// disconnect
folderInbox.close(false);
store.close();
} catch (NoSuchProviderException ex) {
System.out.println("No provider for pop3.");
ex.printStackTrace();
} catch (MessagingException ex) {
System.out.println("Could not connect to the message store");
ex.printStackTrace();
} catch (IOException ex) {
ex.printStackTrace();
}
}
/**
* Runs this program with Gmail POP3 server
*/
public static void main(String[] args) {
String host = "pop.gmail.com";
String port = "995";
String userName = "username";
String password = "password";
String saveDirectory = "D:/Attachment";
EmailAttachmentReceiver receiver = new EmailAttachmentReceiver();
receiver.setSaveDirectory(saveDirectory);
receiver.downloadEmailAttachments(host, port, userName, password);
}
}
答案 0 :(得分：0)
我使用类似的代码并且可以连接（参见javamail-samples.zip中的代码示例，例如msgshow.java）：
Properties props = System.getProperties();
props.setProperty("mail.pop3.socketFactory.class","javax.net.ssl.SSLSocketFactory");
props.setProperty("mail.pop3.socketFactory.fallback", "false");
props.setProperty("mail.pop3.socketFactory.port",String.valueOf(port));
Session session = Session.getInstance(props, null);
Store store = null;
store = session.getStore(protocol); // protocol is e.g. "pop3" or "imap"
store.connect(host, port, user, password);