主要用于混淆时第三方jar包出错问题
-keep class javax.mail.**{*;}
-keep class javax.mail.internet.**{*;}-keep class org.apache.commons.mail.**{*;}
-keep class javax.mail.**{*;}
-keep class javax.mail.internet.**{*;}
-keep class org.apache.commons.mail.**{*;}
-keep class javamail.** {*;}
-keep class javax.mail.** {*;}
-keep class javax.activation.** {*;}
-keep class com.sun.mail.dsn.** {*;}
-keep class com.sun.mail.handlers.** {*;}
-keep class com.sun.mail.smtp.** {*;}
-keep class com.sun.mail.util.** {*;}
-keep class mailcap.** {*;}
-keep class mimetypes.** {*;}
-keep class myjava.awt.datatransfer.** {*;}
-keep class org.apache.harmony.awt.** {*;}
-keep class org.apache.harmony.misc.** {*;}
copied from : http://blog.youkuaiyun.com/pkuyjxu/article/details/8614496