从POJO生成Json Schema

  • Z时代
  • 2024-01-10
  • 分类：问答

我有的：

我正在从pojo生成JSON模式。我的生成架构的代码如下所示：

ObjectMapper mapper = new ObjectMapper();
TitleSchemaFactoryWrapper visitor = new TitleSchemaFactoryWrapper();
mapper.acceptJsonFormatVisitor(clazz, visitor);
JsonSchema schema = visitor.finalSchema();
schemas.put(clazz, mapper.writerWithDefaultPrettyPrinter().writeValueAsString(schema));

我通过上面的代码生成了几个模式。其中一个pojos具有内部嵌入式枚举，以限制可能的值，如下所示：

public class MyClass {
    @JsonProperty("name")
    private String name;
    @JsonProperty("startDayOfWeek")
    private MyClass.StartDayOfWeek startDayOfWeek;
    /**
     * The ID of a timezone returned by the timezones route.
     * 
     */
    @JsonProperty("timezone")
    private String timezone;
    @JsonIgnore
    private Map<String, Object> additionalProperties = new HashMap<String, Object>();
    /**
     * 
     * @return
     *     The startDayOfWeek
     */
    @JsonProperty("startDayOfWeek")
    public MyClass.StartDayOfWeek getStartDayOfWeek() {
        return startDayOfWeek;
    }
    /**
     * 
     * @param startDayOfWeek
     *     The startDayOfWeek
     */
    @JsonProperty("startDayOfWeek")
    public void setStartDayOfWeek(MyClass.StartDayOfWeek startDayOfWeek) {
        this.startDayOfWeek = startDayOfWeek;
    }
    public static enum StartDayOfWeek {
        MONDAY("Monday"),
        TUESDAY("Tuesday"),
        WEDNESDAY("Wednesday"),
        THURSDAY("Thursday"),
        FRIDAY("Friday"),
        SATURDAY("Saturday"),
        SUNDAY("Sunday");
        private final String value;
        private static Map<String, MyClass.StartDayOfWeek> constants = new HashMap<String, MyClass.StartDayOfWeek>();
        static {
            for (MyClass.StartDayOfWeek c: values()) {
                constants.put(c.value, c);
            }
        }
        private StartDayOfWeek(String value) {
            this.value = value;
        }
        @JsonValue
        @Override
        public String toString() {
            return this.value;
        }
        @JsonCreator
        public static MyClass.StartDayOfWeek fromValue(String value) {
            MyClass.StartDayOfWeek constant = constants.get(value);
            if (constant == null) {
                throw new IllegalArgumentException(value);
            } else {
                return constant;
            }
        }
    }
}

上面的代码应将传递给“星期一”，“星期二”，“星期三”等的JSON数据中可能的String值限制。

当我在有问题的代码上运行模式生成器时，我希望得到类似以下模式的内容：

{
  "type" : "object",
  "javaType" : "my.package.MyClass",
  "properties": {
    "startDayOfWeek" : {
      "type" : "string",
      "enum" : [ "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday", "Sunday" ]
    }
  }
}

但是相反，我得到这个：

{
  "type" : "object",
  "id" : "urn:jsonschema:my:package:MyClass",
  "title" : "Lmy/package/MyClass;",
  "properties" : {
    "startDayOfWeek" : {
      "type" : "string"
    }
  }
}

我在Jackson模式模块源代码中做了一些挖掘，发现发生的事情是Jackson使用“

.toString（）”作为枚举类型的默认序列化方法，但是我需要做的是创建一行基于以下内容StartDayOfWeek.values()：

"enum" : [ "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday", "Sunday" ]

有谁知道这是怎么做到的吗？

回答：

Storme的答案参考org.codehaus，它是jackson的旧版本。以下内容相似，但使用的是fastxml（新版本）。

Pom：

<dependency>
    <groupId>com.fasterxml.jackson.core</groupId>
    <artifactId>jackson-core</artifactId>
    <version>2.7.1</version>
</dependency>
<dependency>
    <groupId>com.fasterxml.jackson.core</groupId>
    <artifactId>jackson-databind</artifactId>
    <version>2.7.1</version>
</dependency>
<dependency>
    <groupId>com.fasterxml.jackson.core</groupId>
    <artifactId>jackson-annotations</artifactId>
    <version>2.7.1</version>
</dependency>
<dependency>
    <groupId>com.fasterxml.jackson.module</groupId>
    <artifactId>jackson-module-jsonSchema</artifactId>
    <version>2.1.0</version>
</dependency>

码：

import ...TargetClass;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.SerializationFeature;
import com.fasterxml.jackson.databind.jsonschema.JsonSchema;
import java.io.IOException;
public final class JsonSchemaGenerator {
    private JsonSchemaGenerator() { };
    public static void main(String[] args) throws IOException {
        System.out.println(JsonSchemaGenerator.getJsonSchema(TargetClass.class));
    }
    public static String getJsonSchema(Class clazz) throws IOException {
        ObjectMapper mapper = new ObjectMapper();
        mapper.configure(SerializationFeature.WRITE_ENUMS_USING_TO_STRING, true);
        JsonSchema schema = mapper.generateJsonSchema(clazz);
        return mapper.writerWithDefaultPrettyPrinter().writeValueAsString(schema);
    }
}

以上是 从POJO生成Json Schema 的全部内容， 来源链接： utcz.com/qa/415404.html

回到顶部