You probably have some other "Date" class imported somewhere (or you have a Date class in you package, which does not need to be imported). With "import java.util.*" you are using the "other" Date. In this case it's best to explicitly specify java.util.Date in the code.

Or better, try to avoid naming your classes "Date".

The line:

import java.util.*

doesn't just import Scanner. It brings everything from the java.util namespace into your imports.

You'll have AbstractCollection, Collection, Comparator, Deque, Enumeration, ... all the way to Vector and WeakHashMap.

Write what you mean and mean what you write. You aren't intending to bring everything in the java.util package into your namespace. You want to bring one class. Bringing in too much, especially in this day of easily adding imports to a class and collapsing all them at the top is unnecessary.

^{In days of old, long before IDEs for Java were commonplace, I'll certainly admit to doing an import of * into my class. It was easier to write the import in vi, and it saved a few back and forth to the compiles to say "oh, I don't have java.awt.Color in here, but I've already got java.awt.Button and java.awt.GridBagLayout and java.awt.GridBigConstraints and... frack... I'll just do import java.awt.* and be done with it" Those were in the days of old. You don't do that anymore, especially for one class.}

Furthermore, most IDEs will automatically convert the import of java.util.* into what you want, unless you actually are importing everything in the package (sometimes seen with "I'm importing all the my.package.exceptions that I wrote" or "I'm importing all the my.package.dtos that I wrote").

The statement java.util.*; imports all of the java.util package members so that you don't have to use a package member's fully qualified name. According to the JavaDocs here the package java.util

Contains the collections framework, legacy collection classes, event model, date and time facilities, internationalization, and miscellaneous utility classes (a string tokenizer, a random-number generator, and a bit array)

Although this approach can seem more convenient and is sometimes appropriate you shouldn't always be including an import java.util.*; statement at the beginning of all of your files unless you are using a substantial amount of the members contained in the java.util package. Only include the members that you use like so:

import java.util.ArrayList;
import java.util.LinkedList;

By doing so it helps make you more familiar with each package member that you're using instead of blindly importing the whole package. The most important reason is that by using the wildcard character(*) you have a greater chance of coming across name ambiguities which can lead to errors.

import java.awt.*;
import java.util.*;

In the above code example, the class List becomes ambiguous because both packages have a List class.