检查数组中的时间并打印时间范围内的最新时间

Question

Let's say I have a list of data in the following format:

ID#,YYYYMMDD HH:MM:SS.sss,score

So the data could look like this:

501,20220104 13:12:07.005,25
501,20220104 13:12:07.002,25
500,20220106 09:04:10.013,10
501,20220104 13:12:07.001,25
501,20220104 13:12:07.003,25
501,20220104 13:12:07.004,25
501,20220104 15:20:50.011,25

I want to program the following in Java :

1. Submit data to an Array only if the Score is above 20 (in this example list, 6 out of 7 are).
2. Order the submitted list in descending order from earliest to latest (current listed items aren't in descending order)
3. From there, determine if a single ID (for an arcade system) has more than 5 scores above 20 (True, 6 for Arcade ID 501 in the example) and if 5 scores exactly are within a 2 minute period (which there are 5) and print the earliest Date-Time and Arcade ID with a score above 20 points ( 20220104 13:12:07.001 ).
4. I also need to reformat the Date-Time, but that's another issue I'd rather tackle later.

---

I think I already know how to split up the data:

ArrayList<String> scoreData = new ArrayList<>(Arrays.asList(data.split(",")));
String arcadeID = scoreData.get(0);
Date dateTime = scoreData.get(1);
int score = scoreData.get(2);

And then how to pass that data to a new Array and sort it afterwards in descending order:

Date[] scoresAbove20;

if (score > 20) {
    scoresAbove20.push(dateTime);
    Arrays.sort(scoresAbove20);
}

From the scoresAbove20 Array, I am not sure how to:

1. Check that at least 5 times in the Array are within a 2 minute period
2. Print the earliest Date-Time within the 2 minute period
3. Printing out the Arcade ID with at least 5 times in the Array within a 2 minute period

Answer 1

Define a class, a record specifically, to represent each row of data.

record Score( int id , LocalDateTime when , int score ) { }

Never use either of the legacy Date classes. For date-time handling, use only the modern java.time classes defined in JSR 310.

Define a formatter to parse your date-time string.

DateTimeFormatter formatter = DateTimeFormatter.ofPattern( "uuuuMMdd HH:mm:ss.SSS" );

Parse as a LocalDateTime object, a date with time-of-day but lacking the context of a time zone or offset-from-UTC.

After parsing each of the three input fields, instantiate a record.

Score s = new Score( id , when , score );

Add that object to a list.

List < Score > scores = new ArrayList <>( lines.size() );

When done, you should have a list like this one:

scores.toString() = [Score[id=501, when=2022-01-04T13:12:07.005, score=25], Score[id=501, when=2022-01-04T13:12:07.002, score=25], Score[id=500, when=2022-01-06T09:04:10.013, score=10], Score[id=501, when=2022-01-04T13:12:07.001, score=25], Score[id=501, when=2022-01-04T13:12:07.003, score=25], Score[id=501, when=2022-01-04T13:12:07.004, score=25], Score[id=501, when=2022-01-04T15:20:50.011, score=25]]

String input =
        """
        501,20220104 13:12:07.005,25
        501,20220104 13:12:07.002,25
        500,20220106 09:04:10.013,10
        501,20220104 13:12:07.001,25
        501,20220104 13:12:07.003,25
        501,20220104 13:12:07.004,25
        501,20220104 15:20:50.011,25
        """;
List < String > lines = input.lines().toList();

record Score( int id , LocalDateTime when , int score ) { }
DateTimeFormatter formatter = DateTimeFormatter.ofPattern( "uuuuMMdd HH:mm:ss.SSS" );
List < Score > scores = new ArrayList <>( lines.size() );
for ( String line : lines )
{
    String[] fields = line.split( "," );
    if ( fields.length != 3 ) { throw new IllegalStateException( "Did not find three fields." ); }
    int id = Integer.parseInt( fields[ 0 ] );
    LocalDateTime when = LocalDateTime.parse( fields[ 1 ] , formatter );
    int score = Integer.parseInt( fields[ 2 ] );
    Score s = new Score( id , when , score );
    scores.add( s );
}
System.out.println( "scores = " + scores );

Now you have some objects on which you can apply your business logic, as stated in your 1-2-3 items.

I'll not do your entire schoolwork assignment for you, and I have probably done too much. So I will leave you with this key point for performing that logic: To check for which items are in a two minute period, Use the LocalDateTime methods isEqual , isBefore , isAfter , to compare.

I recommend using the Half-Open approach to defining a span of time. This means the beginning is inclusive while the ending is exclusive . So you will be checking if the score's date-time is equal to or after the beginning and the score's date-time is before the end. Tip: A shorter way of asking "is equal to or after" is to ask "is not before".