Java Date constructor trolling: when 1 means February, not January
Description
Spongebob’s ‘Yup’ meme is recreated in a cave setting. In each panel, a blue-gloved hand labeled “Date” and a superhero figure with the Java logo on his face have a dialogue in bright yellow caption text. Panel 1 shows the hand holding a card that says “Date” while the villain asks, “This is your date class, right?”; Java replies, “Yup.” Panel 2: “And everyone agrees that the number 1 represents January, right?” - Java: “Yup.” Panel 3: “Then the number I put in the month value in the constructor should be the same?” - Java: “Makes sense to me.” Panel 4: “What month does the number 1 represent?” - Java answers, “February.” The joke highlights the historic java.util.Date/Calendar API quirk where months are zero-indexed, causing off-by-one bugs and developer frustration. Visually, the Java logo is superimposed on the superhero in every response frame, emphasizing that the language’s standard library design is the culprit
Comments
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java.util.Date: where 0 is January, 1 is February, and every project plan is off-by-one sprint because someone trusted the constructor
After 20 years in the industry, I've seen teams spend millions migrating from java.util.Date, only to discover their offshore contractors are still using Calendar.getInstance() because 'it worked in the tutorial from 2003' - and somehow that's still more reliable than the junior who tried to fix it with SimpleDateFormat in a multithreaded environment
Ah yes, java.util.Date - the API that taught an entire generation of developers that January is the loneliest number (zero). Nothing says 'enterprise-grade design' quite like requiring a PhD in off-by-one arithmetic just to wish someone Happy New Year. At least when we migrated to java.time, we got to experience the joy of explaining to stakeholders why we needed three sprints to fix 'just changing how we store dates.' The real kicker? Somewhere in a Fortune 500 codebase, there's still a comment that says '// month is 0-indexed, don't forget!' right above code that forgets
Senior dev wisdom: Subtract one from the month before new Date() - legacy tax even stdlib can't escape
Nothing screams enterprise legacy like an API where January is 0, years start at 1900, and off-by-one is a feature - aka java.util.Date
Legacy Java Date: where 1 means February - off-by-one shipped as a feature and the official fix is spelled JSR‑310
Isn’t it deprecated tho? Comment deleted
This is stupid. Any reasonable person thinking about how months would be represented should know that the first month should be 0. Comment deleted
I think it's hard to switch from computer array to real-life array and it can cause mistakes. But in programmer way you're right, why we need in array first null cell, that only use allocated memory, when we can only think from 0 Comment deleted
Because Java is written in C. He-he. https://www.cplusplus.com/reference/ctime/tm/ Comment deleted
its just 0 indexing them Comment deleted
Same in JavaScript Comment deleted