TextTitle throws NullPointerException fo rnull parameters:
` public TextTitle(String text, Font font, Paint paint,
RectangleEdge position,
HorizontalAlignment horizontalAlignment,
VerticalAlignment verticalAlignment,
RectangleInsets padding) {

    super(position, horizontalAlignment, verticalAlignment, padding);

    if (text == null) {
        throw new NullPointerException("Null 'text' argument.");
    }
    if (font == null) {
        throw new NullPointerException("Null 'font' argument.");
    }
    if (paint == null) {
        throw new NullPointerException("Null 'paint' argument.");
    }
    this.text = text;
    this.font = font;
    this.paint = paint;
    // the textAlignment and the horizontalAlignment are separate things,
    // but it makes sense for the default textAlignment to match the
    // title's horizontal alignment...
    this.textAlignment = horizontalAlignment;
    this.backgroundPaint = null;
    this.content = null;
    this.toolTipText = null;
    this.urlText = null;

}`

Other classes throw IllegalArgumentException. For example:

public TextLine(String text, Font font, Paint paint) { if (text == null) { throw new IllegalArgumentException("Null 'text' argument."); } if (font == null) { throw new IllegalArgumentException("Null 'font' argument."); } if (paint == null) { throw new IllegalArgumentException("Null 'paint' argument."); } this.fragments = new java.util.ArrayList<>(); final TextFragment fragment = new TextFragment(text, font, paint); this.fragments.add(fragment); }

Another example:

public TextFragment(String text, Font font, Paint paint, float baselineOffset) { if (text == null) { throw new IllegalArgumentException("Null 'text' argument."); } if (font == null) { throw new IllegalArgumentException("Null 'font' argument."); } if (paint == null) { throw new IllegalArgumentException("Null 'paint' argument."); } this.text = text; this.font = font; this.paint = paint; this.baselineOffset = baselineOffset; }