public SqlRexConvertlet get(SqlCall call) {
SqlRexConvertlet convertlet;
final SqlOperator op = call.getOperator();
// Is there a convertlet for this operator
// (e.g. SqlStdOperatorTable.plusOperator)?
convertlet = (SqlRexConvertlet) map.get(op);
if (convertlet != null) {
return convertlet;
}
// Is there a convertlet for this class of operator
// (e.g. SqlBinaryOperator)?
Class<? extends Object> clazz = op.getClass();
while (clazz != null) {
convertlet = (SqlRexConvertlet) map.get(clazz);
if (convertlet != null) {
return convertlet;
}
clazz = clazz.getSuperclass();
}
// Is there a convertlet for this class of expression
// (e.g. SqlCall)?
clazz = call.getClass();
while (clazz != null) {
convertlet = (SqlRexConvertlet) map.get(clazz);
if (convertlet != null) {
return convertlet;
}
clazz = clazz.getSuperclass();
}
return null;
}
private static Method findMethod(Class<?> clazz, String name, Class... parameterTypes) {
try {
return clazz.getMethod(name, parameterTypes);
} catch (NoSuchMethodException e) {
throw new RuntimeException(e);
}
}