By list, you mean a java.util.List? If so, you need to convert your list to an array of primitive doubles then pass it to the Constant op (or TFloat64 if you want to create a tensor that feeds a model). There are many ways of doing this. e.g. in Java,
Ops tf = Ops.create(...);
double[] array = list.stream().mapToDouble(x -> x).toArray();
Constant<TFloat64> constant = tf.constant(array);
try (TFloat64 tensor = TFloat64.vectorOf(array)) { ... }

Whenever possible, you should try to work directly with primitive types rather than their boxed type though (i.e. double vs Double), performance gains can be substantial.