Java Class to JSON Schema Generator
Convert Java POJOs/DTOs/records into JSON Schema. Use the quick Mock Generator shortcut to create matching sample JSON without leaving the page.
Need JSON to Java?
Generate strongly-typed Java POJOs from JSON samples.
Java code Input
JSON Schema Output
Paste your Java classes to produce a JSON Schema instantly.
Supports collections, nested objects, Maps, and popular annotations.
Frequently Asked Questions
What kinds of Java code are supported?
The converter understands common POJOs, Lombok data classes, records, builders, and DTOs that contain nested objects, generics, arrays, Lists/Sets, and Maps. It reads annotations like @JsonProperty, @SerializedName, @JsonInclude, and nullable hints to keep naming and optionality aligned with your serialization framework.
How accurate is the data-type detection?
Primitive wrappers (Integer, Double, Boolean, etc.), Java time types, enums, Optionals, and generic collections all map to their closest JSON Schema equivalents. When type information is missing (for example, raw List fields without generics) we warn you and fall back to reasonable defaults so the schema remains valid.
How can I turn the schema into mock JSON data?
After the schema is generated, click "Generate Mock Data" to open the Mock Generator with your schema preloaded. From there you can configure locales, array counts, and instantly create realistic sample payloads.
How do I choose the root class when multiple classes exist?
Open the settings panel and select any parsed class from the dropdown. By default we pick the first public class, but you can switch to nested classes or DTOs declared later in the file at any time without reloading the page.