It is not exactly what we need. We will access plantuml.jar very randomly. It can be single expression or multiple formulas at once. But we need a single call of plantuml.jar per expression. The "-clipboard" option must indicate a start of special mode for plantuml.jar. It looks in clipboard for text and ALWAYS generates a bitmap. That means, if an erroneuos state (no text, bad syntax, etc) will be occur, then a bitmap "Bad Input data" or similar schould be placed in clipboard. In our software it will be immediately visualized. As example i provide a some fragment of our symbolic processor
The expressions will be first translated in AsciiMath text with colors and font states and then over call to plantuml.jar rendered in bitmaps. So we doing a loop over expresssions and will use in this loop plantuml.jar for current expression on the fly :-)
PS. Usage of FTP is limited for our clients due to their offline state or many restrictions to access an online service.