JarCasting
JAVA POJO Class Generate with jsonSchemaUrl Annotation
json-schema-pojo is a library that automatically generate JAVA POJO class file on compile time. (like lombok library)
Just add maven repository dependency,
<dependency>
<groupId>com.github.whsoul</groupId>
<artifactId>json-schema-pojo</artifactId>
<version>X.Y.Z</version>
</dependency>
and make config class With Annotations,
then Java compiler make POJOs along annotation configs.
Base Use
public class ConfigClass {
@JsonSchemaPojo(packageName = "com.test.pojo"
, className = "Datas"
, schemaUrl = "https://whsoul.github.io/json-schema-pojo/test-schema01.json")
public String fromExternalResource;
@JsonSchemaPojo(packageName = "com.test.pojo2"
, className = "Sample"
, schemaUrl = "sample_schema_01.json")
public String fromOwnResource;
there are 2 kind of options with target schema
- internet resource reference ( offline mode, not available )
- my own(or downloaded) schema ( under
src/main/resources)
- sample_schema_01.json
And also you can inject custom configurations, such as below
Base Config Enable/Disable
@JsonSchemaPojo(packageName = "com.test.sample1", className = "Student"
, schemaUrl = "sample_schema_01.json"
, baseConfig = {
@JsonSchemaPojo.BaseConfig(
feature = JSONSCHEMA_POJO_FEATURE.STRING_ENUM_AS_ENUM
,enable = true
)
})
public String enableDisableBaseConfig;
Control library generate default actions with config enable/disable
Customize Type Mapping
@JsonSchemaPojo(packageName = "com.test.sample1", className = "Student"
, schemaUrl = "sample_schema_01.json"
, typeMappingConfig = {
@JsonSchemaPojo.TypeMappingConfig(
typeName = "string"
, typeJavaClass = MyString.class
),
@JsonSchemaPojo.TypeMappingConfig(
typeName = "integer"
, typeJavaClass = int.class
),
@JsonSchemaPojo.TypeMappingConfig(
typeName = "customFloat"
, typeJavaClass = float.class
)
}
)
public String sampleClass1;
Standard json schema specification support only simpleTypes below
| type | default mapping |
|---|---|
| string | String.class |
| boolean | boolean.class |
| long | long.class |
| integer | Integer.class |
| number | Double.class |
| array | List.class |
| object | Map.class |
| null | Void.class |
but customType supported. override default mapping also
Customize Validation Annotation Config
@JsonSchemaPojo(packageName = "com.test.sample1", className = "Student"
, schemaUrl = "sample_schema_01.json"
, annotationConfig = {
@JsonSchemaPojo.AnnotationConfig(
type = ANNOTATION_TYPE.FIELD_REQUIRED
, annotationClass = MyNotNull.class
)
}
)
public String sampleClass1;
Add Interface, Superclass with
@JsonSchemaPojo(packageName = "com.test.sample1", className = "Student"
, schemaUrl = "sample_schema_01.json"
,superclassConfig = {
@JsonSchemaPojo.SuperConfig(
superclass = A.class
, targetClassNames = "com.test.sample1.Student" +
",com.test.sample1.definitions.University" +
",com.test.sample1.definitions.University.Location"
)
}
,superinterfaceConfig = {
@JsonSchemaPojo.SuperConfig(
superclass = BInterface.class
, targetClassNames = "com.test.sample1.Student" +
",com.test.sample1.definitions.University" +
", com.test.sample1.definitions.University.Location "
)
}
)
public String sampleClass1;
if you want to add superclass or interface to generated classes, you can use superclassConfig, superinterfaceConfig
Usage Example
API Specifications exchange for caller(client with java)
Java base (Client - Server), (Server - Server) easily exchanges Request, Response data format.
API Server Application
- Develop Java API Application with json Request, Response
- Generate jsonSchema file (Request Model, Response Model)
- Create automatically generate with 3rd party POJO to Json schema library below Reference(#1) ( or Create jsonSchema Structure by your self)
- Deploy the static files with your API Server application, or other static CDN (example] http://your.application.domain/my-api001-REQUEST-schema.json, ... my-api001-RESPONSE-schema.json )
- Let client know your Server API url with and the schema file download URL
Java Client
-
Add this library at pom or gradle
-
Add @JsonSchemaPojo in your code, and schema download url
@JsonSchemaPojo(packageName = "com.test.pojo"
, className = "Api001RequestPojo"
, schemaUrl = "http://your.application.domain/my-api001-REQUEST-schema.json")
public String yourApi001Request;
References
Jackson Json Schema Module (#1)
JSON Schema Draft v3
https://github.com/FasterXML/jackson-module-jsonSchema