无法使用mailR包发送电子邮件

Question

我得到下面提到的错误。我将mail.jar，activation.jar，mailapi.jar，common-lang3.jar复制到了/ usr / lib / jvm / java-8-openjdk-amd64 / jre / lib / ext

java.lang.NoClassDefFoundError: javax/activation/DataHandler
    at org.apache.commons.mail.Email.createMimeMessage(Email.java:1832)
    at org.apache.commons.mail.Email.buildMimeMessage(Email.java:1268)
    at org.apache.commons.mail.Email.send(Email.java:1436)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.base/java.lang.reflect.Method.invoke(Method.java:564)
    at RJavaTools.invokeMethod(RJavaTools.java:386)
Caused by: java.lang.ClassNotFoundException
    at RJavaClassLoader.findClass(RJavaClassLoader.java:383)
    at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:566)
    at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:499)
    ... 8 more
NULL
Error: NoClassDefFoundError (Java): javax/activation/DataHandler

Answer 1

Vince Fulco提供的链接中的评论之一在Ubuntu 18.04中可用：https : //github.com/rpremraj/mailR/issues/77#issuecomment-465741847

特别：

1. 下载以下.jar文件：

   • https://mvnrepository.com/artifact/javax.activation/javax.activation-api/1.2.0
   • https://mvnrepository.com/artifact/com.sun.activation/javax.activation/1.2.0

2. 找出java-mailR文件夹：system.file（“ java”，package =“ mailR”）

   • 就我而言：“ / home / MY_USERNAME / R / x86_64-pc-linux-gnu-library / 3.5 / mailR / java”

3. 将两个.jar文件复制到该文件夹​​中

以防万一，在尝试之前，我重新启动了计算机。

Answer 2

这是 github 上经过充分讨论且迄今为止尚未解决的问题。 https://github.com/rpremraj/mailR/issues/77