Free online JSON to Java Class tool. Auto-generate POJO classes with getter/setter/Lombok/Jackson annotation support.
TL;DR: Free JSON to Java Class tool. Auto-generate POJO classes with getter/setter/Lombok/Jackson annotation support. Runs locally with no data leakage.
For local tools, open DevTools → Network and search your input — it should not appear in requests.
Next steps
Usage Guide
Scaffold Java classes from JSON: package, accessors, Lombok, Jackson/Gson name annotations, lossless numbers. Trim to records and validation in your repo.
1. Steps
Nested objects become classes; empty arrays become List<Object> until you add samples.
- Paste JSON; set class and optional package.
- Toggle accessors / Lombok.
- Pick annotation style and copy.
2. Three traps
- Money / snowflake IDs → BigDecimal / long.
- Date strings stay String until you wire formats.
- null → Object; refine with more samples.
3. Lombok and annotations
Align Lombok policy team-wide. Jackson/Gson help when keys differ from camelCase.
4. Schema drift
- Regenerate against a second real payload.
- Unknown-field policy lives in your mapper config.
- Rename auto classes before merge.
5. Pair tools
- TS → JSON to TypeScript.
- Go → JSON to Go.
- Reverse → Java to JSON.
6. Privacy
Local convert; still redact production samples before pasting.
FAQ
Yes. You can opt for generated getter/setter methods, or for Lombok @Data and Jackson serialization annotations, matching different Java coding habits.
Treat them as drafts. The output is plain fields plus accessors, meant to be rewritten to your project's Lombok, record, or validation-annotation conventions. Consider Optional for nullable fields, and align the array-versus-List choice and nested type names with your codebase style.
Nested levels are parsed recursively, each becoming its own Java class, with arrays and lists mapped to the corresponding types. For complex structures, get the output compiling first, then fill in annotations.
Go small before going big: confirm the output shape on a trimmed sample, then scale to the full payload — oversized input can make the tab lag, and repeated clicks stack tasks. When committing or sharing the result, label it as a generated draft and note what it does not guarantee.
Nothing at all: no fee, no login — paste JSON and the class draft is produced locally.
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