Using calendar class with Arraylist

[Ryan Gordon]

Hello, Im trying to display a train time table to look like this
Station      Arrival     Departure Day
Vancouver                   20:30 1
Kamloops         06:00   06:35 2
Jasper        16:00   17:30 2
Edmonton        23:00   23:59 2
Saskatoon        08:00   08:25 3
Winnipeg        20:45    22:30 3
Sioux Lookout 05:02   05:42 4
Hornepayne 15:35   16:10 4
Capreol        00:18    00:48 5
Toronto        09:30        5

This is my code

import java.util.ArrayList;
import java.util.Calendar;
//import java.util.Date;
import java.util.List;

public class Station {
	private Calendar arrival;
	private Calendar departure;
	private int day;
	private String city;
        
public Station(String city, Calendar arrival, Calendar departure, int day){
this.city = city;
this.arrival = arrival;
this.departure = departure;
this.day = day;
}

public String toString() {
		return city + " " + arrival + " " + departure + " " + day;	}

    /**
     * @return the arrival
     */
    public Calendar getArrival() {
        return arrival;
    }

    /**
     * @param arrival the arrival to set
     */
    public void setArrival(Calendar arrival) {
        this.arrival = arrival;
    }

    /**
     * @return the departure
     */
    public Calendar getDeparture() {
        return departure;
    }

    /**
     * @param departure the departure to set
     */
    public void setDeparture(Calendar departure) {
        this.departure = departure;
    }

    /**
     * @return the day
     */
    public int getDay() {
        return day;
    }

    /**
     * @param day the day to set
     */
    public void setDay(int day) {
        this.day = day;
    }

    /**
     * @return the city
     */
    public String getCity() {
        return city;
    }

    /**
     * @param city the city to set
     */
    public void setCity(String city) {
        this.city = city;
    }
        
    public Calendar getArrivalDate(){
        return getArrivalDate();
    } 
    
    public Calendar getDepartureDate() {
        return arrival;
    }
	
    
	
}

and

import java.util.*;
import java.util.Calendar;

public class TrainTimeTable {
	

	public static void main(String[] args) {
		Calendar s = Calendar.getInstance();
		
		//creating class objects
            Station s1 = new Station("Station: Vancouver",null, null, 0);
            Station s2 = new Station("Station: kamloops", null, null, 0);
            Station s3 = new Station("Station: Jasper", null, null, 0);
            Station s4 = new Station("Station: Edmonton", null, null, 0);
            Station s5 = new Station("Station: Saskatoon", null, null, 0);
            Station s6 = new Station("Station: Winnipeg", null, null, 0);
            Station s7 = new Station("Station: Sioux Lookout", null, null, 0);
            Station s8 = new Station("Station: Hornepayne", null, null, 0);
            Station s9 = new Station("Station: Capreol", null, null, 0);
            Station s10 = new Station("Station: Toronto", null, null, 0);
            //creating arraylist
            ArrayList<Station> schedule = new ArrayList<Station>();
            schedule.add(s1);
            schedule.add(s2);
            schedule.add(s3);
            schedule.add(s4);
            schedule.add(s5);
            schedule.add(s6);
            schedule.add(s7);
            schedule.add(s8);
            schedule.add(s9);
            schedule.add(s10);
            
            //iterator
            Iterator itr = schedule.iterator();
            //traversing elements of arraylist object
            while(itr.hasNext()){
            Station st = (Station)itr.next();
            System.out.println(st.getCity()+ st.getArrival() + st.getDepartureDate() + st.getDay());
            }
		}
}

The result is get in command prompt is

Station: Vancouvernullnull0
Station: kamloopsnullnull0
Station: Jaspernullnull0
Station: Edmontonnullnull0
Station: Saskatoonnullnull0
Station: Winnipegnullnull0
Station: Sioux Lookoutnullnull0
Station: Hornepaynenullnull0
Station: Capreolnullnull0
Station: Torontonullnull0

How can I get rid of the null and put in the appropriate times and days?
Thank you in advance for any help.

[Carey Brown]

If you are using Java 8, which I would highly recommend, use the LocalTime class not the Calendar class.

LocalTime arrival = LocalTime.of( hour, minute );

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

System.out.println( (arrival==null?"     ":formatter.format( arrival )) );

I'm not sure why you're doing this when you have a Station#toString() method defined (though it could use some tweaks).
           Iterator itr = schedule.iterator();            //traversing elements of arraylist object            while(itr.hasNext()){            Station st = (Station)itr.next();            System.out.println(st.getCity()+ st.getArrival() + st.getDepartureDate() + st.getDay());            }
This would be much cleaner.

for( Station st : schedule ) {
    System.out.println( st );
}

[Ryan Gordon]

Hello, Thank you for the help. I tried doing what you said

import java.util.*;
import java.util.Calendar;
import java.time.LocalTime;
//import java.time.LocalDate;

public class TrainTimeTable {
	
	public static void main(String[] args) {
	
	LocalTime arrival = LocalTime.of(9, 05 );
 
	DateTimeFormatter formatter = DateTimeFormatter.ofPattern( "HH:mm" );
 
	System.out.println( (arrival==null?"     ":formatter.format( arrival )) );
		Calendar s = Calendar.getInstance();
		
		//creating class objects
            Station s1 = new Station("Station: Vancouver",null, null, 0);
            Station s2 = new Station("Station: kamloops", null, null, 0);
            Station s3 = new Station("Station: Jasper", null, null, 0);
            Station s4 = new Station("Station: Edmonton", null, null, 0);
            Station s5 = new Station("Station: Saskatoon", null, null, 0);
            Station s6 = new Station("Station: Winnipeg", null, null, 0);
            Station s7 = new Station("Station: Sioux Lookout", null, null, 0);
            Station s8 = new Station("Station: Hornepayne", null, null, 0);
            Station s9 = new Station("Station: Capreol", null, null, 0);
            Station s10 = new Station("Station: Toronto", null, null, 0);
            //creating arraylist
            ArrayList<Station> schedule = new ArrayList<Station>();
            schedule.add(s1);
            schedule.add(s2);
            schedule.add(s3);
            schedule.add(s4);
            schedule.add(s5);
            schedule.add(s6);
            schedule.add(s7);
            schedule.add(s8);
            schedule.add(s9);
            schedule.add(s10);
            
            for( Station st : schedule ) {
    System.out.println( st );
}
		}
}

but I am getting these erros

TrainTimeTable.java:4: error: package java.time does not exist
import java.time.LocalTime;
                ^
TrainTimeTable.java:12: error: cannot find symbol
        LocalTime arrival = LocalTime.of(9, 05 );
        ^
  symbol:   class LocalTime
  location: class TrainTimeTable
TrainTimeTable.java:12: error: cannot find symbol
        LocalTime arrival = LocalTime.of(9, 05 );
                            ^
  symbol:   variable LocalTime
  location: class TrainTimeTable
TrainTimeTable.java:14: error: cannot find symbol
DateTimeFormatter formatter = DateTimeFormatter.ofPattern( "HH:mm" );
^
  symbol:   class DateTimeFormatter
  location: class TrainTimeTable
TrainTimeTable.java:14: error: cannot find symbol
DateTimeFormatter formatter = DateTimeFormatter.ofPattern( "HH:mm" );
                              ^
  symbol:   variable DateTimeFormatter
  location: class TrainTimeTable
5 errors

I must be missing something, please help.

[Carey Brown]

package java.time does not exist

This means you are using an older version of Java. Can you update your Java to version 8 ?

[Ryan Gordon]

yes I installed it and still getting the error

C:\Users\Administrator>java -version
java version "1.8.0_151"
Java(TM) SE Runtime Environment (build 1.8.0_151-b12)
Java HotSpot(TM) Client VM (build 25.151-b12, mixed mode, sharing)

[Carey Brown]

What do you get with
javac -version
?

[Ryan Gordon]

javac 1.7.0_80

[Carey Brown]

I'm guessing you installed Java not the Java Development Kit (JDK). You'll need the Java 8 JDK in order to compile correctly.

[Carey Brown]

Download HERE

[Ryan Gordon]

i downloaded the current version but javac -version is still coming up 1.7...

[Knute Snortum]

What do your PATH and JAVA_HOME environment variables look like?

Windows:
C:>path

and

c:> echo %JAVA_HOME%

Linux:
$ echo $PATH

and

$ echo JAVA_HOME

[Ryan Gordon]

C:\Users\Administrator>path
PATH=C:\ProgramData\Oracle\Java\javapath;C:\WINDOWS\system32;C:\WINDOWS;C:\WINDOWS\System32\Wbem;C:\WINDOWS\System32\WindowsPowerShell\v1.0\;C:\Program Files\Java\jdk1.7.0_80\bin;;%USERPROFILE%\AppData\Local\Microsoft\WindowsApps

C:\Users\Administrator>echo %JAVA_HOME%
%JAVA_HOME%

[Carey Brown]

Ryan Gordon wrote:C:\Users\Administrator>path
PATH=C:\ProgramData\Oracle\Java\javapath;C:\WINDOWS\system32;C:\WINDOWS;C:\WINDOWS\System32\Wbem;C:\WINDOWS\System32\WindowsPowerShell\v1.0\;C:\Program Files\Java\jdk1.7.0_80\bin;;%USERPROFILE%\AppData\Local\Microsoft\WindowsApps

C:\Users\Administrator>echo %JAVA_HOME%
%JAVA_HOME%

Your path should replace the bolded section with
%JAVA_HOME%\bin

And you should create a brand new environment variable
JAVA_HOME
set to
C:\Program Files\Java\jdk1.8.0_151

[Ryan Gordon]

I tried that it didn't work.

[Campbell Ritchie]

Ryan Gordon wrote:. . .

import java.util.*;
import java.util.Calendar;
import java.time.LocalTime;
// . . .

. . . .

Whenever you get your installation problem sorted out, use the java.time classes instead of Calendar, not in addition to. More details of the newer classes here in the Java™ Tutorials.

Always tell us what is going wrong, not “it doesn't work”. Start with the results of passing
echo %PATH%
or simply path
to the command line. Make sure to follow Carey't instructions. You have to be exact to the letter.

[Carey Brown]

Ryan Gordon wrote:I tried that it didn't work.

Ok, you've changed the path and JAVA_HOME, just to double check re-run

C:>path

and

c:> echo %JAVA_HOME%

And post the results

[Carey Brown]

Carey Brown wrote:C:\Program Files\Java\jdk1.8.0_151

Also, use Windows Explorer to verify that this directory exists.

[Ryan Gordon]

I did as you said and made my system variables as follows

PATH=C:\ProgramData\Oracle\Java\javapath;C:\WINDOWS\system32;C:\WINDOWS;C:\WINDOWS\System32\Wbem;C:\WINDOWS\System32\WindowsPowerShell\v1.0\;  %JAVA_HOME%\bin;;%USERPROFILE%\AppData\Local\Microsoft\WindowsApps
and

The JAVA_HOME to C:\Program Files\Java\jdk1.8.0_151

still not working please help.

[Knute Snortum]

Try this:

c:>where javac

and post what gets printed

[Ryan Gordon]

C:\Users\Administrator>where javac
'where' is not recognized as an internal or external command,
operable program or batch file.

[Knute Snortum]

I've never seen a Windows OS that didn't have "where.exe".  Hmm...

Okay, the "wrong" javac is probably in here:

C:\ProgramData\Oracle\Java\javapath

Not sure what to do without messing with your PATH variable.  Get me a second...

[Knute Snortum]

One last thing before we change your PATH.  Type this:

C:\>dir C:\ProgramData\Oracle\Java\javapath

...and post what it displays.

[Ryan Gordon]

C:\Users\Administrator>C:\>dir C:\ProgramData\Oracle\Java\javapath
'C:\' is not recognized as an internal or external command,
operable program or batch file.

[Knute Snortum]

Ah!  At the command prompt, just type this:

where javac

...and press return.

[Ryan Gordon]

C:\>where javac
'where' is not recognized as an internal or external command,
operable program or batch file.

[Knute Snortum]

Drat!  Okay, just this at the command prompt:

dir C:\ProgramData\Oracle\Java\javapath

Press <enter> and post the result.

[Ryan Gordon]

C:\Users\Administrator>dir C:\ProgramData\Oracle\Java\javapath
Volume in drive C has no label.
Volume Serial Number is 86EE-9CE9

Directory of C:\ProgramData\Oracle\Java\javapath

12/18/2017  05:37 PM    <DIR>          .
12/18/2017  05:37 PM    <DIR>          ..
12/18/2017  05:36 PM           206,912 java.exe
12/18/2017  05:36 PM           206,912 javaw.exe
12/18/2017  05:36 PM           319,552 javaws.exe
              3 File(s)        733,376 bytes
              2 Dir(s)  394,987,880,448 bytes free

[Knute Snortum]

Where is javac.exe hiding?  Okay, try this:

dir C:\WINDOWS\system32\java*.*

and post the results.

[Ryan Gordon]

C:\Users\Administrator>dir C:\WINDOWS\system32\java*.*
Volume in drive C has no label.
Volume Serial Number is 86EE-9CE9

Directory of C:\WINDOWS\system32

01/10/2017  08:56 PM    <DIR>          java
09/29/2017  08:41 AM            94,720 JavaScriptCollectionAgent.dll
06/29/2017  03:22 PM           318,528 javaws.exe
              2 File(s)        413,248 bytes
              1 Dir(s)  393,966,690,304 bytes free

[Knute Snortum]

When you changed the PATH or JAVA_HOME, did you start a new command window?  If not, exit the command window and restart it.  Then type

javac -version

and see if it's Java 8.

[Ryan Gordon]

C:\Users\Administrator>javac -version
'javac' is not recognized as an internal or external command,
operable program or batch file.

[Knute Snortum]

Use the Windows Explorer and see if you can find this folder:

C:\Program Files\Java\jdk1.8.0_151\bin

Does it have javac.exe in it?

[Ryan Gordon]

In this file C:\Program Files (x86)\Java\jdk1.8.0_151\bin i have javac

[Ryan Gordon]

it doesnt end with .exe though

[Knute Snortum]

Okay, change JAVA_HOME to:

C:\Program Files (x86)\Java\jdk1.8.0_151

Then you should be ok.

[Ryan Gordon]

I actually already have it set to that I cant believe this happened all I tried to do was get the newest java version:(
Thank you for all your help so far i appreciate it.

[Campbell Ritchie]

Ryan Gordon wrote:it doesnt end with .exe though

Maybe your Windows® Explorer has the hide extensions for well-known file types option turned on.

What happens when you pass path or echo %PATH% to a command line? Are you still getting the same response from java -version and javac -version? Have you got either C:\Program Files (x86)\Java\jdk1.8.0_151\bin or %JAVA_HOME%\bin in your PATH? Did you install Java® into the x86 folders, or did it do that by itself? Please confirm whether you downloaded a 32‑bit version or a 64‑bit version of the JDK. Have you still got the space in the PATH before %JAVA_HOME%?

Short of getting remote access to your computer (we promise to copy all your card numbers and empty your bank accounts), we can only help if we get the full details from you.

[Ryan Gordon]

Maybe your Windows® Explorer has the hide extensions for well-known file types option turned on.

What happens when you pass path or echo %PATH% to a command line? Are you still getting the same response from java -version and javac -version? Have you got either C:\Program Files (x86)\Java\jdk1.8.0_151\bin or %JAVA_HOME%\bin in your PATH? Did you install Java® into the x86 folders, or did it do that by itself? Please confirm whether you downloaded a 32‑bit version or a 64‑bit version of the JDK. Have you still got the space in the PATH before %JAVA_HOME%?

Short of getting remote access to your computer (we promise to copy all your card numbers and empty your bank accounts), we can only help if we get the full details from you.



C:\Users\Administrator>path
PATH=C:\ProgramData\Oracle\Java\javapath;C:\WINDOWS\system32;C:\WINDOWS;C:\WINDOWS\System32\Wbem;C:\WINDOWS\System32\WindowsPowerShell\v1.0\;C:\Program Files (x86)\Java\jdk1.8.0_151 \bin;C:\Users\Administrator\AppData\Local\Microsoft\WindowsApps;

C:\Users\Administrator>echo %PATH%
C:\ProgramData\Oracle\Java\javapath;C:\WINDOWS\system32;C:\WINDOWS;C:\WINDOWS\System32\Wbem;C:\WINDOWS\System32\WindowsPowerShell\v1.0\;C:\Program Files (x86)\Java\jdk1.8.0_151 \bin;C:\Users\Administrator\AppData\Local\Microsoft\WindowsApps;

I put it in that folder by myself and I downloaded a 64 bit version as my computer is 64 bit. Lol that was a joke about the bank accounts right :P

[Knute Snortum]

There's the problem!  You have an extra space in your PATH.

Check your JAVA_HOME variable; edit it and go to the end of the text.  There will probably be a space at the end.  Delete it.

Now, remember to exit and restart a command window, then type:

javac -version

[Dave Tolls]

Using the "quote" button for that post it looks like it's actually a new line, and not a space.