question: public void printStackTrace ( java . io . PrintStream ps ) { if ( rootCause != null ) { String superString = super . toString ( ) ; synchronized ( ps ) { ps . print ( superString + ( superString . endsWith ( "." ) ? "" : "." ) + "  Root exception is " ) ; rootCause . printStackTrace ( ps ) ; } } else { super . printStackTrace ( ps ) ; } }
target:  Prints this exception's stack trace to a print stream. If this exception has a root exception, the stack trace of the root exception is printed to the print stream instead.