ColumnReference implements Expression { public Iterable<Expression> children() { return Collections.emptyList(); } ColumnReference(TableReference tableReference,
                         Column<T> column); void visit(ExpressionVisitor visitor); Class<T> typeConstraint(); Iterable<Expression> children(); int compareTo(Expression e); boolean equals(Object o); int hashCode(); final TableReference tableReference; final Column<T> column; }
@Test public void noChildren() { assertTrue(Iterables.isEmpty(colRef.children())); }