jquick-pdf line chart Y-axis tick rounding causes the last point to hang in mid-air: all three AIs misdiagnosed it as a SQL problem

The last point of the jquick-pdf line chart "hanging in mid-air" is not a data error, but the mathematical inevitability of Y-axis automatic nice-ing rounding the upper limit up from the data maximum of 25680 to 30000 with an interval of 5000. All three AIs misdiagnosed it as a SQL statistical scope or date grouping problem; in reality, you only need to manually set min(0).max(30000).interval(5000) on JValueAxis to align the ticks. After manually setting max, out-of-range data will not raise an error, and points will be silently drawn outside the canvas.