dev90 10 Light Poster

Hello,
I am new to visAD library. I am trying to plot a 'lowerTerrain.nc' file in visAD.

But its longitude(-180 to +180) and latitude(-80 to +80) ranges are displayed automatically in -150 to +150 for longitude range(X axis) and -90 to +90 in latitude range(Y Axis).

I have tried this:

LatLonLines longLine=new latLonLines(RealType.Longitude,-180.0f,180.0f,30.0f);
longLine.setVisible(true);

But I don't know how to add this longLine object on the display.

REFERENCE: https://www.unidata.ucar.edu/software/idv/docs/javadoc/ucar/visad/display/LatLonLines.html