I am looking for a solution similiar to PDFBox for PDFs of Apache Tika, however, for PS files.
thanks.
Like James Black says, it's probably best just to convert to PDF and use your familiar tools.
However, there does exist pstotext which is available in, e.g., the Ubuntu universe in its own package.
Ghostscript itself also comes with both ps2txt and ps2ascii which can also do this.