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Java Define immutable data with a record

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JavaIntermediate

Define immutable data with a record. Learn the syntax using an editable java example.

When to use it

Use this technique in small programs, reusable helpers and everyday debugging. Check the input types, any required imports, and whether the operation changes existing values or produces a new result.

Syntax

class Main { public static void main(String[] a) { System.out.println(new Point(2,3).x()); } }

Parameters

Inspect the literals, variables and function arguments used in the example. Replace values with compatible java types before testing.

Returns / effect

Expected demonstration result: 2.

Java · Editable example
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Expected output

2

Common mistake and fix

Match the required syntax and test boundary cases.

Good practices

Keep the example small, check its documented output, then adapt it to your own project with validation and error handling.

Practice exercise

Try changing one input in the define immutable data with a record example. Predict how the output changes, then compare with the reference output.

Compatibility: Confirm support in your installed language/runtime version; some examples need modern standard libraries.

Related concepts: basics, examples, syntax

Explain this code

This java example shows how to define immutable data with a record. It uses a small, reproducible input so you can inspect the behavior without changing a production project.

Try a small exercise

Try changing one input in the define immutable data with a record example. Predict how the output changes, then compare with the reference output.

Show a hint

Change a single literal or input first; compare the result before making more edits.

Show example solution
record Point(int x, int y) {}
class Main { public static void main(String[] a) { System.out.println(new Point(2,3).x()); } }

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