Here are some speech packages available for the Java API along with their links:

  1. FreeTTS - A speech synthesis system written entirely in the Java programming language. It is based upon Flite: a small run-time speech synthesis engine developed at Carnegie Mellon University.

Link: https://freetts.com/

  1. MaryTTS - An open-source, multilingual text-to-speech synthesis system written in pure Java.

Link: https://marytts.github.io/

  1. Sphinx4 - A pure Java speech recognition framework that supports the recognition of both, continuous and isolated speech.

Link: https://cmusphinx.github.io/sphinx4/

  1. Google Cloud Text-to-Speech API - A cloud-based API that enables developers to synthesize natural-sounding speech with more than 100 voices in multiple languages and variants.

Link: https://cloud.google.com/text-to-speech

  1. Amazon Polly - A cloud-based service that provides text-to-speech capabilities, including dozens of lifelike voices and support for multiple languages.

Link: https://aws.amazon.com/polly/