File Format APIs for Java
Open Source Java APIs for Email Files
Read, Write & Extract Attachments from MSG files via Java.
Email File Format APIs for Java Include
Apache POI HSMF
Java implementation of the Outlook MSG format providing low-level read access to MSG files along with a user-facing way to get at the common textual content of MSG files.
Develop Java applications having the ability to Read and convert Microsoft Outlook PST Files using open source Java libraries.
Simple Java Mail
Open Source Java library supports creating email message with attachments or encrypt/decrypt messages, CLI support, S/MIME support and advanced batch processing.
Free Java library allows to access, read, send Email messages. You can add attachments, mark emails, move messages, delete a particular email inside Java apps.