JsonWriter: Write non-finite floating-point values as strings#4080
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JsonWriter: Write non-finite floating-point values as strings#4080
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This change updates `JsonWriter` to serialize non-finite `float` and `double` values (`NaN`, `Infinity`, and `-Infinity`) as JSON strings. This behavior aligns with Jackson's `JsonWriteFeature#WRITE_NAN_AS_STRINGS`. Previously, these values were written without quotes, which produces **invalid JSON** according to the JSON specification.
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Pull request overview
Updates JsonWriter so that non-finite floating-point values (NaN, Infinity, -Infinity) are serialized as JSON strings, producing valid JSON output and aligning behavior with Jackson’s JsonWriteFeature#WRITE_NAN_AS_STRINGS.
Changes:
- Serialize non-finite
float/doublevalues as quoted strings inJsonWriter. - Add parameterized tests covering non-finite
float/doubleserialization. - Add a changelog entry documenting the fix.
Reviewed changes
Copilot reviewed 3 out of 3 changed files in this pull request and generated 2 comments.
| File | Description |
|---|---|
src/changelog/.2.x.x/4080_jtl-nan.xml |
Adds changelog entry for the non-finite float/double JSON serialization fix. |
log4j-layout-template-json/.../JsonWriter.java |
Writes non-finite float/double values via writeString(...) instead of emitting invalid JSON numbers. |
log4j-layout-template-json-test/.../JsonWriterTest.java |
Adds parameterized tests asserting non-finite values are quoted. |
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This change updates
JsonWriterto serialize non-finitefloatanddoublevalues (NaN,Infinity, and-Infinity) as JSON strings.This behavior aligns with Jackson's
JsonWriteFeature#WRITE_NAN_AS_STRINGS.Previously, these values were written without quotes, which produces invalid JSON according to the JSON specification.