@Override
	public boolean isCellEditable(int rowIndex, int columnIndex) {
		if (getNumSelectedRows() > 1) {
			return false;
		}
		if (columnIndex == LENGTH) {
			return false;
		}
		if (rowIndex < 0 || rowIndex >= getRowCount()) {
			return false;
		}
		if (columnIndex < 0 || columnIndex >= getColumnCount()) {
			return false;
		}
		DataTypeComponent dtc = viewComposite.getComponent(rowIndex);
		if (dtc == null) {
			return false;
		}
		boolean notDefined = (viewComposite.getDefinedComponentAtOrdinal(rowIndex) == null);
		return !(notDefined && (columnIndex == OFFSET));
	}
Gets called to update/validate the current editable location in the table

@param value the new cell value
@param rowIndex the row index in the component table
@param columnIndex the column index for the table cell in the current model
@return true if the field was updated or validated successfully
Ghidra/Features/Base/src/main/java/ghidra/app/plugin/core/stackeditor/StackEditorModel.java