I have an ArrayList including several number of time-stamps and the aim is finding the difference of the first and the last elements of the ArrayList.
String a = ArrayList.get(0);
String b = ArrayList.get(ArrayList.size()-1);
long diff = b.getTime() - a.getTime();
I also converted the types to int but still it gives me an error The method getTime is undefined for the type String.
Additional info :
I have a class A which includes
String timeStamp = new SimpleDateFormat("ss S").format(new Date());
and there is a class B which has a method private void dialogDuration(String timeStamp)
and dialogueDuration method includes:
String a = timeSt.get(0); // timeSt is an ArrayList which includes all the timeStamps
String b = timeSt.get(timeSt.size()-1); // This method aims finding the difference of the first and the last elements(timestamps) of the ArrayList (in seconds)
long i = Long.parseLong(a);
long j = Long.parseLong(b);
long diff = j.getTime()- i.getTime();
System.out.println("a: " +i);
System.out.println("b: " +j);
And one condition is that the statement(String timeStamp = new SimpleDateFormat("ss S").format(new Date());) wont be changed in class A. And an object of class B is created in class A so that it invokes the dialogueDuration(timeStamp) method and passes the values of time-stamps to class B.
My problem is this subtraction does not work, it gives an error cannot invoke getTime() method on the primitive type long. It gives the same kind of error also for int and String types?
Thanks a lot in advance!
Maybe like this:
SimpleDateFormat dateFormat = new SimpleDateFormat("ss S");
Date firstParsedDate = dateFormat.parse(a);
Date secondParsedDate = dateFormat.parse(b);
long diff = secondParsedDate.getTime() - firstParsedDate.getTime();
Assuming you have Timestamp objects or Date Objects in your ArrayList you could do:
Timestamp a = timeSt.get(0);
Timestamp b = timeSt.get(timeSt.size()-1);
long diff = b.getTime() - a.getTime();
You can calculate the difference with the both following methods(also you can modify the mentioned methods to return difference as 'millisecond', 'day', 'month', etc by adding additional if statement or using switch case):
private Long calculateDifference(String date1, String date2, String value) {
Timestamp date_1 = stringToTimestamp(date1);
Timestamp date_2 = stringToTimestamp(date2);
long milliseconds = date_1.getTime() - date_2.getTime();
if (value.equals("second"))
return milliseconds / 1000;
if (value.equals("minute"))
return milliseconds / 1000 / 60;
if (value.equals("hours"))
return milliseconds / 1000 / 3600;
else
return new Long(999999999);
}
private Timestamp stringToTimestamp(String date) {
try {
SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
Date parsedDate = dateFormat.parse(date);
return new Timestamp(parsedDate.getTime());
} catch (Exception e) {
return null;
}
}
For example:
calculateDifference("2021-10-20 10:00:01", "2021-10-20 10:15:01", "minute");
will return '-15'
or
calculateDifference("2021-10-20 12:00:01", "2021-10-20 10:15:01", "minute");
will return '105'
You should make your ArrayList x to an ArrayList<TimeStamp> x. Subsequently, your method get(int) will return an object of type TimeStamp (instead of a type String). On a TimeStamp you are allowed to invoke getTime().
By the way, do you really need java.sql.TimeStamp? Maybe a simple Date or Calendar is easier and more appropriate.
Related
It wont get the minutes. i need to return minutes.
How to return sum of minutes while iterating over Localtime in Java?
public String userLunchHoursSum(String username) {
List<WorkHour> workHours = workHourRepository.findWorkHoursByUsername(username);
System.out.println(Arrays.toString(workHours.toArray()));
long diff = 0;
LocalTime lunchTime;
long minutes = 0;
LocalTime plusMinutes = null;
for (WorkHour workHour : workHours) {
lunchTime = workHour.getLunch_time().toLocalTime(); //00:30:00
plusMinutes = lunchTime.plusMinutes(lunchTime.getMinute());
}
if(workHours.size()!= 0) {
return Long.toString(plusMinutes.getMinute());
}
return "00:00";
}
getLunch_time returns java.sql.Time.
As mentioned, you should be storing duration instead of localtime. If this is something you have no control over, consider migrating the database or creating a intermediate parsing function. Example code that I have not run, because I don't know what is in WorkHour.
// leave the string formatting to other functions
public long userLunchHoursSum(String username) {
List<WorkHour> workHours = workHourRepository.findWorkHoursByUsername(username);
Duration totalDuration = Duration.ZERO;
for (WorkHour workHour : workHours) {
// save your time in the appropriate format beforehand
// do not use local time to store duration.
Duration lunchTime = Duration.between(LocalTime.MIDNIGHT, workHour.getLunch_time().toLocalTime()); //00:30:00
totalDuration = totalDuration.plus(lunchTime);
}
return totalDuration.toMinutes();
}
Different behaviour of RRULE based on start time :
Hi, I am currently trying to write a cron to rrule convertor and encountered some issues with some particular rules.
For the following rule :
"FREQ=YEARLY;BYMONTH=1,2,3,4,5,6,7,8,9,10,11,12;BYMONTHDAY=1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31;BYDAY=SU,MO,TU,WE,TH,FR,SA;BYHOUR=0,10,20;BYMINUTE=0"
The behaviour of the dates iterator iss different depending on what the start time specified is :
final String rule2 = "FREQ=YEARLY;BYMONTH=1,2,3,4,5,6,7,8,9,10,11,12;BYMONTHDAY=1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31;BYDAY=SU,MO,TU,WE,TH,FR,SA;BYHOUR=0,10,20;BYMINUTE=0";
final Date startDate = new SimpleDateFormat("yyyy-MM-dd").parse("2019-10-01");
final Date startDate2 = new SimpleDateFormat("yyyy-MM-dd").parse("2019-12-01");
System.out.println("Biweekly Rule Date 1");
final List<Date> biweeklyStartDate1 = biweeklyDates(rule2, startDate, 100);
System.out.println("Biweekly Rule Date 1 Result Count " + biweeklyStartDate1.size());
System.out.println("Biweekly Rule Date 2");
final List<Date> biweeklyStartDate2 = biweeklyDates(rule2, startDate2, 100);
System.out.println("Biweekly Rule Date 2 Result Count " + biweeklyStartDate2.size());
private static List<Date> biweeklyDates(final String rule, final Date date, final int limit) {
final RecurrenceRuleScribe scribe = new RecurrenceRuleScribe();
final ParseContext context = new ParseContext();
context.setVersion(ICalVersion.V2_0);
final RecurrenceRule recurrenceRule = scribe.parseText("RRULE:" + rule,null, new ICalParameters(), context);
final DateIterator iterator = recurrenceRule.getDateIterator(date, TimeZone.getTimeZone("GMT"));
final List<Date> values = new ArrayList<>();
while (iterator.hasNext()) {
final Date next = iterator.next();
values.add(next);
System.out.println(new SimpleDateFormat("yyyy-MM-dd").format(next));
if (values.size() >= limit) {
break;
}
}
return values;
}
In this example I try to retrieve a 100 occurences using the same rule. The occurences returned differ based on start time specified.
The first date would return the expected 100 results, the second one would return a single invalid occurence, which seem to be the start date.
It seems to be caused by last month of the year, whn specifying another date with December, the same return seems to be returned.
Google-rfc-2445 has the same behaviour but ical4j and some other rrule evaluators from other languages were able to produce the expected results.
I have trouble finding elements, here is my code:
public static void main(String[] args) {
BufferedReader br = getFileReader("reader.csv");
ArrayList<Monitoring> col = getCollection(br);
//sort the collection on 'beginTime'
for (Monitoring x : col)
System.out.println(x.toString());
BeginTimeComparator beginTime = new BeginTimeComparator();
Collections.sort(col,beginTime);
System.out.println("Begin time:");
for (Monitoring x : col)
System.out.println(x.toString());
This is the part I have trouble with, I don't know how to search en get back the object with endTime 2015-03-10.
BTW this is one line of cvs data:
UnitId;BeginTime;EndTime;Type;Min;Max;Sum
14100072;2015-03-10 07:12:20;2015-03-10 7:13:20;Gps/GpsAccuracyGyroBias;0;0;0
//find the amount of elements that were sent on 'endTime' = 2015-03-10 (just the date)
EndTimeComparator endTime = new EndTimeComparator();
String findThis = "2015-03-10";
Collections.sort(col, endTime);
for(Monitoring x : col){
if(x.getEndTime().equals(findThis)){
System.out.println("Here is 'endTime= 2015-03-10' :");
System.out.println(x.toString());
}
}
I have tried this but both didn't work:
int index = Collections.binarySearch(col, findThis.toString(), null);
System.out.println("Here is 'endTime= 2015-03-10' :");
System.out.println(index);
Guessing that getEndTime() returns a LocalDateTime you can't compare a string with a type of LocalDateTime. You could try to parse the LocalDateTime to LocalDate and fill the 'findThis' variabel with a type of LocalDate.
Because code says more than a 1000 words:
EndTimeComparator endTime = new EndTimeComparator();
Collections.sort(col, endTime);
DateTimeFormatter dtf = DateTimeFormatter.ofPattern("yyyy-MM-dd");
LocalDate findThis = LocalDate.parse("2015-03-10", dtf);
System.out.println("Here is 'endTime= 2015-03-10' :");
for (Monitoring x : col) {
if (x.getEndTime().toLocalDate().equals(findThis)) {
System.out.println(x.toString());
}
}
You need to provide Comparator for that null or Monitoring should implement comparable (both of them should compare items by time field that you need).
Collections.binarySearch(col, findThis.toString(), null);
According to the example data you provided
UnitId;BeginTime;EndTime;Type;Min;Max;Sum
14100072;2015-03-10 07:12:20;2015-03-10 7:13:20;Gps/GpsAccuracyGyroBias;0;0;0
endTime is "2015-03-10 7:13:20", not "2015-03-10", so using equals will not work. Instead, you could try using startsWith:
String findThis = "2015-03-10";
for (Monitoring x : col) {
if (x.getEndTime().startsWith(findThis)) {
System.out.println("Here is 'endTime= 2015-03-10': ");
System.out.println(x.toString());
}
}
Or even better: Instead of storing the begin and end times as strings, convert them to Date objects or similar when you read the objects from CSV.
I needed to set all zeros in Timestamp instance.
Here is the code I tried
import java.sql.Timestamp;
public class UI
{
public static void main(String args[])
{
Timestamp timestamp = Timestamp.valueOf("0000-00-00 00:00:00.0");
System.out.println(timestamp);
}
}
It is showing output
0002-11-30 00:00:00.0
How to set the value of Timestamp so that output will show
0000-00-00 00:00:00.0
It is not possible to instantiate a Timestamp to 0000-00-00 00:00:00.
valueOf calls a constructor, which in the source code has the following javadocs (taken from offical javadocs API):
Constructs a Timestamp object initialized with the given values.
Deprecated: instead use the constructor Timestamp(long millis)
Parameters:
year the year minus 1900
month 0 to 11
date 1 to 31
hour 0 to 23
minute 0 to 59
second 0 to 59
nano 0 to 999,999,999
The date parameter must be of value between 1-31.
'0000-00-00 00:00:00' can not be represented as java.sql.Timestamp
Try this
public class Test {
public static void main(String[] args) {
try {
String[] s = {"0001-01-01 00:00:00.0", "0000-00-00 00:00:00"};
for (String value : s) {
Timestamp t = Timestamp.valueOf(value);
System.out.println(t.toString() + ", " + t.getTime());
}
} catch (Exception e) {
System.out.println(e.getMessage());
}
}
}
There is no 0th month which has a 0th day (and no 0th year depending on your calendar). If you want to change how the timestamp prints you can do this
Timestamp ts = new Timestamp(Long.MIN_VALUE) {
public String toString() {
return "0000-00-00 00:00:00.0";
}
};
This will print the way you expect.
A quick check on the java.sql.Timestamp Documentation reveals that the Class - Timestamp only supports the following parameter values:
year - the year minus 1900
month - 0 to 11
date - 1 to 31
hour - 0 to 23
minute - 0 to 59
second - 0 to 59
nano - 0 to 999,999,999
So, the answer to your question is that, you cannot set the value to:
0000-00-00 00:00:00.0
However, you can set the hour, minute, second and nanosecond value to 00:00:00.0.
Were you able to execute your code successfully?
Executing your code resulted in:
Exception in thread "main" java.lang.IllegalArgumentException: Timestamp format must be yyyy-mm-dd hh:mm:ss[.fffffffff]
at java.sql.Timestamp.valueOf(Unknown Source)
It is actually possible to do this via reflection. Internally the timestamp object has another date object which is not accessible outside.
public static void convertTimestampToZero(final Timestamp t) {
// normalize the timestamp to generate internal date object
t.toString();
// reset the nano seconds
resetInternalDateField(t, "fastTime");
resetInternalDateField(t, "nanos");
// get the internal date object
Field cdateField = getDeclaredFieldInHierarchy(t.getClass(), "cdate");
Object cdate = getIgnoreAccess(t, cdateField);
// convert fields to zero
resetInternalDateField(cdate, "year");
resetInternalDateField(cdate, "month");
resetInternalDateField(cdate, "dayOfMonth");
resetInternalDateField(cdate, "dayOfWeek");
resetInternalDateField(cdate, "hours");
resetInternalDateField(cdate, "minutes");
resetInternalDateField(cdate, "seconds");
resetInternalDateField(cdate, "millis");
resetInternalDateField(cdate, "fraction");
}
private static void resetInternalDateField(final Object o, final String fieldName) {
Field field = getDeclaredFieldInHierarchy(o.getClass(), fieldName);
setIgnoreAccess(o, field, 0);
}
public static Field getDeclaredFieldInHierarchy(final Class<?> cls, final String fieldName) {
if (null == cls) {
return null;
}
List<Field> fields = getDeclaredFieldsInHierarchy(cls);
for (Field field : fields) {
if (field.getName().equals(fieldName)) {
return field;
}
}
return null;
}
Just implement the getIgnoreAccess/setIgnoreAccess methods which just get/set the value of a field via reflection ignoring the access modifiers.
And here's a test:
#Test
void shouldGenerateAZeroTimestamp() {
Timestamp t = new Timestamp(4324629);
convertTimestampToZero(t);
assertThat(t.toString(), equalTo("0000-00-00 00:00:00.0"));
}
I am pulling 2 time values (as strings) from an XML file using xpath, these values (for example) are as follows:
00:07
08:00
00:07 is equal to 7 minutes
08:00 means 8am, with no date associated or needed (that is handled elsewhere)
Each of these values is subject to change in each XML file that i read. What i am attempting to do is as follows:
I need to subtract or add (depending on the situation) the 7mins from the 8am and give me a hh:mm time (eg: 07:53 or 08:07) in a string that i can eventually output to CSV
Next i need to produce 2 additional strings, 1 min before and 1 min after (eg: 07:52 and 07:54 OR 08:06 and 08:08) which also need to be output to CSV
I have tried everything and i can think of in relation to the time interpretation and manipulation to get the minutes subtracted/added to the time and then +/- 1 min from there, but being a complete novice i am totally stuck despite reading and testing as much as i could find. Spent the last 2 days working with Joda Time for the first time but i must be missing something fundamental as i cannot get the desired result with this either.
The question is - how can i achieve this?
Some sample code that gets me reading from the XML and printing the time
FileInputStream file = null;
try {
file = new FileInputStream(new File("Output/XmlConfig.xml"));
} catch (FileNotFoundException ex) {
Logger.getLogger(KATT.class.getName()).log(Level.SEVERE, null, ex);
}
DocumentBuilderFactory builderFactory = DocumentBuilderFactory.newInstance();
DocumentBuilder builder = null;
try {
builder = builderFactory.newDocumentBuilder();
} catch (ParserConfigurationException ex) {
Logger.getLogger(KATT.class.getName()).log(Level.SEVERE, null, ex);
}
Document xmlDocument = null;
try {
xmlDocument = builder.parse(file);
} catch (SAXException ex) {
Logger.getLogger(KATT.class.getName()).log(Level.SEVERE, null, ex);
} catch (IOException ex) {
Logger.getLogger(KATT.class.getName()).log(Level.SEVERE, null, ex);
}
XPath xPath = XPathFactory.newInstance().newXPath();
//get In Early rule from XML
String exceptionInEarlyXML = "Root/Response/WSAExceptionRule/#InEarly";
NodeList nodeListInEarly = null;
try {
nodeListInEarly = (NodeList) xPath.compile(exceptionInEarlyXML).evaluate(xmlDocument, XPathConstants.NODESET);
} catch (XPathExpressionException ex) {
Logger.getLogger(KATT.class.getName()).log(Level.SEVERE, null, ex);
}
String exceptionInEarly = (nodeListInEarly.item(1).getFirstChild().getNodeValue());
String InEarly = exceptionInEarly;
SimpleDateFormat format = new SimpleDateFormat("hh:mm");
Date d2 = null;
try {
d2 = format.parse(InEarly);
} catch (ParseException ex) {
Logger.getLogger(KATT.class.getName()).log(Level.SEVERE, null, ex);
}
DateTime dt2 = new DateTime(d2);
System.out.println(dt2);
This give me an output of 1970-01-01T00:07:00.000+10:00
I have tried so many permutations of code that i am at the point of deleting and starting again from scratch as it is un-compilable, and i am not experienced enough yet to be able to solve this issue.
Once you have the Date object for the parsed time, use getTime() to get the time in milliseconds and save it into a long variables. Then parse the offset time format and use a NumberFormat to get the number of minutes to offset. Add or subtract as needed. Take the result and create a new Date(millis) then apply your format to it.
Here is a working example:
String sTime = "08:00";
String sOffset ="00:07";
SimpleDateFormat dateFormat = new SimpleDateFormat("hh:mm");
Date dtTime = null;
try {
dtTime = dateFormat.parse(sTime);
} catch (ParseException e) {
// handle exception
return;
}
String[] offsetHrsMins = null;
NumberFormat numberFormat = NumberFormat.getNumberInstance();
long offsetMillis = 0;
try {
offsetHrsMins = sOffset.split(":");
long offsetHrs = (Long) numberFormat.parse(offsetHrsMins[0]);
long offsetMins = (Long) numberFormat.parse(offsetHrsMins[1]);
offsetMillis = 1000 * 60 * ((offsetHrs * 60) + offsetMins);
} catch (ParseException e) {
// handle exception
return;
}
long lTime = dtTime.getTime();
System.out.println("Adding minutes: " + dateFormat.format(new Date(lTime + offsetMillis)));
System.out.println("Subtracting minutes: " + dateFormat.format(new Date(lTime - offsetMillis)));
output:
Adding minutes: 08:07
Subtracting minutes: 07:53
First, you need to use SimpleDateFormat to parse the Date String to a Java.util.Date Object.
Second, After getting the Date Object, you can easily add/substract some time, and get another Date Object.
Last, you can use another SimpleDateFormat object to format the Date Object you got in second step to String.
SimpleDateFormat is very useful in Processing Date Strings. You can refer to the Javadoc in JDK or search some examples by Google.
Try passing the strings into a method aswel as what you are subrtacting by
Then converting them to ints
Then have an if statment that if the subtraction amount is greater that the minets int
then it subtracts 1 from the hours int and sets the new minets int to 60 subtract the subtraction int
Then convert them back to Strings
Here is the code exept for turing it back into a string
public class Main {
static String hours="8";
static String minets="7";
static String minus="17";
public static void main(String[] args) {
Main m = new Main();
m.timechange(hours,minets,minus);
}
void timechange(String hour, String minuet, String subtract){
int h = Integer.parseInt(hour);
int m = Integer.parseInt(minuet);
int s = Integer.parseInt(subtract);
if(s>m){
h-=1;
m=60-s;
}
else{
m-=s;
}
if ((m>9)&&(h>9)) {
System.out.println(h+":"+m);
} else {if ((m<10)&&(h<10)) {
System.out.println("0"+h+":0"+m);
}else {if ((m<10)&&(h>9)) {
System.out.println(h+":0"+m);
}else {if ((m>9)&&(h<10)) {
System.out.println("0"+h+":"+m);
}
}
}
}
}}
I wasnt sure if you wanted the back to String.
Hopeful that answers your question
The same can be done for when the minets reach over 60 if that ever happens.
Here a genuine Joda-Time answer because OP wants Joda-Time (and I also consider that library as superior to java.util.Date, java.text.SimpleDateFormat etc.):
Joda-Time has the big advantage of having several different temporal types. The right type for handling plain wall times is LocalTime. It also defines a method to add minutes.
Your task:
I need to subtract or add (depending on the situation) the 7mins from the 8am and give me a hh:mm time (eg: 07:53 or 08:07) in a string that i can eventually output to CSV
Next i need to produce 2 additional strings, 1 min before and 1 min after (eg: 07:52 and 07:54 OR 08:06 and 08:08) which also need to be output to CSV
The solution (only for part one, the other part is very similar):
LocalTime time = new LocalTime(8, 0); // corresponds to 08:00
LocalTime laterBy8Minutes = time.plusMinutes(7);
LocalTime earlierBy8Minutes = time.minusMinutes(7);
String sLaterBy8Minutes = laterBy8Minutes.toString("HH:mm"); // 08:07
String sEarlierBy8Minutes = earlierBy8Minutes.toString("HH:mm"); // 07:53
One additional note: If you start with another type like java.util.Date and wish to convert it to LocalTime then you can use the constructor
new LocalTime(jdkDate, DateTimeZone.forID("Europe/Moscow")) // example
or for default timezone:
new LocalTime(jdkDate)