if (isSingleLine()) { return; }
if (isSingleLine()) return;
void doPageDown(boolean select, int height) {	// do nothing if in single line mode. fixes 5673	if (isSingleLine()) {		return;	}		int oldColumnX = columnX;	int oldHScrollOffset = horizontalScrollOffset;	if (isFixedLineHeight()) {		int lineCount = content.getLineCount();		int caretLine = getCaretLine();		if (caretLine < lineCount - 1) {			int lineHeight = renderer.getLineHeight();			int lines = height / lineHeight;			int scrollLines = Math.min(lineCount - caretLine - 1, lines);			// ensure that scrollLines never gets negative and at leat one 			// line is scrolled. fixes bug 5602.			scrollLines = Math.max(1, scrollLines);			caretOffset = getOffsetAtPoint(columnX, getLinePixel(caretLine + scrollLines));			if (select) {				doSelection(ST.COLUMN_NEXT);			}			// scroll one page down or to the bottom			int verticalMaximum = lineCount * getVerticalIncrement();			int pageSize = getClientArea().height;			int scrollOffset = getVerticalScrollOffset() + scrollLines * getVerticalIncrement();			if (scrollOffset + pageSize > verticalMaximum) {				scrollOffset = verticalMaximum - pageSize;			}			if (scrollOffset > getVerticalScrollOffset()) {				scrollVertical(scrollOffset - getVerticalScrollOffset(), true);			}		}	} else {		int oldVScrollOffset = getVerticalScrollOffset();		int caretY = getCaret().getLocation().y;		boolean scroll = getLineIndex(getClientArea().height) != content.getLineCount() - 1;		if (scroll) {			scrollVertical(height, true);			claimBottomFreeSpace();		}		caretY += height - (getVerticalScrollOffset() - oldVScrollOffset);		caretOffset = getOffsetAtPoint(columnX, caretY);		setCaretLocation();		if (select) {			doSelection(ST.COLUMN_NEXT);		}	}		showCaret();	int hScrollChange = oldHScrollOffset - horizontalScrollOffset;	columnX = oldColumnX + hScrollChange;}