The Humanist Iranian calendar used in this project is the same as the Solar Hijri calendar with a tiny difference in its year numbering system: its year numbering starts with the foundation of the ancient city of Susa, marking the spark of civilisation in the region.
Excavations have uncovered evidence of continual habitation dating back to 4395 BCE but that early community grew from an even older one dating back to c. 7000 BCE. (World History Encyclopedia)
So the years until Christ's birth are 4395 and until the Hijrah (+621), it would be 5016. If we ignore those 16 years, and add 5000 years into the normal Solar Hijri calendar, we've got ourselves a new year numbering system whose conversion is quite easy! You'll just have to turn the leading "1" in 1404 into "6"...
Here's an example of how it works:
| Solar Hijri | Humanist Iranian |
|---|---|
| 1404 | 6404 |
| 1400 | 6400 |
| 1378 | 6378 |
The java.time package (added since JDK 1.8) is the most modern way to handle date & time in JVM-based languages.
This calendar implementation has only 2 files:
If you're developing an Android app, note that the java.time is supported since Android API 26+. Although you can provide it for earlier Android APIs using the desugaring feature.
I had also implemented the Humanist Iranian calendar for the android.icu.util package which is based upon the old famous ICU library.
Simply implement the JAR output of this project as a dependency in your project.
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