Eclipse: java.lang.NoClassDefFoundError: javax/activation/DataHandler
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Eclipse: java.lang.NoClassDefFoundError: javax/activation/DataHandler
提问by gabboSonc
I'm trying to send an email in java. Here's the code:
我正在尝试用 Java 发送电子邮件。这是代码：
String mailSmtpHost = "smtp.example.com";
String mailTo = "[email protected]";
String mailFrom = "[email protected]";
String mailSubject = "Email subject";
String mailText = "Some text";
Properties properties = new Properties();
properties.put("mail.smtp.host", mailSmtpHost);
Session emailSession = Session.getDefaultInstance(properties);
try {
Message emailMessage = new MimeMessage(emailSession);
emailMessage.addRecipient(Message.RecipientType.TO, new InternetAddress(mailTo));
emailMessage.setFrom(new InternetAddress(mailFrom));
emailMessage.setSubject(mailSubject);
emailMessage.setText(mailText);
emailSession.setDebug(true);
Transport.send(emailMessage);
}catch(Exception e) {
System.out.println("Errore email: "+e.toString());
}
When I compile the project, on line:
当我编译项目时，在线：
Message emailMessage = new MimeMessage(emailSession);
...the following error comes out:
...出现以下错误：
Exception in thread "main" java.lang.NoClassDefFoundError: javax/activation/DataHandler
Note: I'm using java -version: 9.0.4
注意：我正在使用 java -version: 9.0.4
回答by Léo R.
JDK 9 disables access to many of the javax.* APIs by default, javax activation is now deprecated.
默认情况下，JDK 9 禁用对许多 javax.* API 的访问，现在不推荐使用 javax 激活。
However you can resolve it with adding the module at run time
但是，您可以通过在运行时添加模块来解决它
"--add-modules java.activation".
回答by Grzesiek Kapuscinski
download and add external jakarta.activation-1.2.1.jar Its the Jakarta Activation project.
下载并添加外部 jakarta.activation-1.2.1.jar 这是 Jakarta Activation 项目。
