Calculate no of days between two dates Kotlin


#1

I want to calculate no of days between two dates.Dates are in the form of string likes this “2018-04-13T20:00:00.0400” ?


#2

Choose the one you like best :slight_smile:

val date1 = LocalDateTime.parse("2018-04-13T20:00:00.0400")
val date2 = <<other date>>

println(ChronoUnit.DAYS.between(date1, date2))
println(Duration.between(date1, date2).toDays())
println(date1.until(date2, ChronoUnit.DAYS))

#3

This results in this exception
java.time.format.DateTimeParseException: Text ‘2018-04-13T20:00:00.0400’ could not be parsed, unparsed text found at index 10
at java.time.format.DateTimeFormatter.parseResolved0(DateTimeFormatter.java:1952)
at java.time.format.DateTimeFormatter.parse(DateTimeFormatter.java:1851)
at java.time.LocalDate.parse(LocalDate.java:394)
at java.time.LocalDate.parse(LocalDate.java:379)
at waleed.com.eventstoday.ui.home.EventAdapter.calculateNoOfDays(EventAdapter.kt:46)
at waleed.com.eventstoday.ui.home.EventAdapter.onBindViewHolder(EventAdapter.kt:34)
at waleed.com.eventstoday.ui.home.EventAdapter.onBindViewHolder(EventAdapter.kt:20)
at android.support.v7.widget.RecyclerView$Adapter.onBindViewHolder(RecyclerView.java:6673)
at android.support.v7.widget.RecyclerView$Adapter.bindViewHolder(RecyclerView.java:6714)
at android.support.v7.widget.RecyclerView$Recycler.tryBindViewHolderByDeadline(RecyclerView.java:5647)
at android.support.v7.widget.RecyclerView$Recycler.tryGetViewHolderForPositionByDeadline(RecyclerView.java:5913)
at android.support.v7.widget.RecyclerView$Recycler.getViewForPosition(RecyclerView.java:5752)
at android.support.v7.widget.RecyclerView$Recycler.getViewForPosition(RecyclerView.java:5748)
at android.support.v7.widget.LinearLayoutManager$LayoutState.next(LinearLayoutManager.java:2232)
at android.support.v7.widget.LinearLayoutManager.layoutChunk(LinearLayoutManager.java:1559)
at android.support.v7.widget.LinearLayoutManager.fill(LinearLayoutManager.java:1519)
at android.support.v7.widget.LinearLayoutManager.onLayoutChildren(LinearLayoutManager.java:614)
at android.support.v7.widget.RecyclerView.dispatchLayoutStep2(RecyclerView.java:3812)
at android.support.v7.widget.RecyclerView.onMeasure(RecyclerView.java:3225)
at android.view.View.measure(View.java:23169)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6749)
at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1535)
at android.widget.LinearLayout.measureHorizontal(LinearLayout.java:1187)
at android.widget.LinearLayout.onMeasure(LinearLayout.java:706)
at android.view.View.measure(View.java:23169)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6749)
at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1535)
at android.widget.LinearLayout.measureVertical(LinearLayout.java:825)
at android.widget.LinearLayout.onMeasure(LinearLayout.java:704)
at android.view.View.measure(View.java:23169)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6749)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:185)
at android.support.v7.widget.ContentFrameLayout.onMeasure(ContentFrameLayout.java:141)
at android.view.View.measure(View.java:23169)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6749)
at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1535)
at android.widget.LinearLayout.measureVertical(LinearLayout.java:825)
at android.widget.LinearLayout.onMeasure(LinearLayout.java:704)
at android.view.View.measure(View.java:23169)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6749)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:185)
at android.view.View.measure(View.java:23169)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6749)
at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1535)
at android.widget.LinearLayout.measureVertical(LinearLayout.java:825)
at android.widget.LinearLayout.onMeasure(LinearLayout.java:704)
at android.view.View.measure(View.java:23169)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6749)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:185)
at com.android.internal.policy.DecorView.onMeasure(DecorView.java:716)
at android.view.View.measure(View.java:23169)
at android.view.ViewRootImpl.performMeasure(ViewRootImpl.java:2718)
2018-10-11 19:09:27.062 5355-5355/waleed.com.eventstoday E/AndroidRuntime: at android.view.ViewRootImpl.measureHierarchy(ViewRootImpl.java:1572)
at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1855)
at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1460)
at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:7183)
at android.view.Choreographer$CallbackRecord.run(Choreographer.java:949)
at android.view.Choreographer.doCallbacks(Choreographer.java:761)
at android.view.Choreographer.doFrame(Choreographer.java:696)
at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:935)
at android.os.Handler.handleCallback(Handler.java:873)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:193)
at android.app.ActivityThread.main(ActivityThread.java:6669)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:858)


#4

Oh found it … sorry i was making mistake it is using LocalDateTime and i was using LocalDate !!! Thanks @mamax1028


#5

Strictly speaking this is not Kotlin.
These are the Java 8 java.time classes being re-used in a Kotlin program.
Of course, Kotlin’s philosophy based on the recent KotlinConf is partly Reuse as the opening speaker remarked.

However, and strictly to answer the question, it should be qualified whether or not the Kotlin standard library has any data specific stuff (for want of a better word) that replaces that of Java 8.

Furthermore, and based on the recent Oracle changes in Java licensing, I am wondering if those that will switch out of Java, will then have to refactor code that Kotlin relies on? such as the example above.