The META-INF directory in the JAR file

The META-INF directory in the JAR file

The META-INF directory, if it exists, is used to store package and extension configuration data, including security, versioning, extension and services.
The following files/directories in the META-INF directory are recognized and interpreted by the Java 2 Platform to configure applications, extensions, class loaders
and services:

• MANIFEST.MF

.................

Tag libraries should be packed with their .tlds packed in their META-INF directory. JSP engines look through the JAR files in the /lib directory for TLDs and add the tags as necessary. Then when you are installing tag libraries, you only need to deliver one file - the JAR - no changes to the web.xml, no extra tlds hanging around.