从POJO生成Json模式 [英] Generate Json Schema from POJO with a twist

问题描述

我有什么：

我正在从pojo生成JSON模式。我的生成模式的代码如下所示：

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

我通过上述代码生成多个模式。其中一个pojos有一个内部嵌入式枚举来限制可能的值，如下所示：

  public class MyClass {
 
 @JsonProperty（name）
 private String name; 
 @JsonProperty（startDayOfWeek）
 private MyClass.StartDayOfWeek startDayOfWeek; 
 / ** 
 *由时区路线返回的时区的ID。 
 * 
 * / 
 @JsonProperty（timezone）
 private String timezone; 
 @JsonIgnore 
 private Map< String，Object> additionalProperties = new HashMap< String，Object>（）; 
 
 / ** 
 * 
 * @return 
 * startDayOfWeek 
 * / 
 @JsonProperty（startDayOfWeek）
 public MyClass.StartDayOfWeek getStartDayOfWeek（）{
 return startDayOfWeek; 
} 
 
 / ** 
 * 
 * @param startDayOfWeek 
 * startDayOfWeek 
 * / 
 @JsonProperty（ startDayOfWeek）
 public void setStartDayOfWeek（MyClass.StartDayOfWeek startDayOfWeek）{
 this.startDayOfWeek = startDayOfWeek; 
} 
 
 public static enum StartDayOfWeek {
 
 MONDAY（Monday），
 TUESDAY（Tuesday），
 WEDNESDAY 星期三），
 THURSDAY（星期四），
 FRIDAY（星期五），
 SATURDAY（星期六），
 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; 
} 
} 
 
} 
 
} 
  

上述代码应该将传递到星期一，星期二，星期三等的JSON数据中的可能的String值限制在

当我在有问题的代码上运行模式生成器时，我希望得到以下模式：

  
type：object，
javaType：my.package.MyClass，
properties：{
startDayOfWeek：{
 type：string，
enum：[星期一，星期二，星期三，星期四，星期五 
} 
} 
  

而是我得到这个：

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

我已经在Jackson Schema Module源代码中进行了一些挖掘，并且发现发生了什么事情是Jackson的使用.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基于 StartDayOfWeek.values（）的行： p

 枚举：[星期一，星期二，星期三，星期四 ，星期天] 
  

有谁知道该怎么做？

解决方案

Storme的回答引用 org.codehaus ，这是一个较旧的杰克逊版本。以下是类似的，但是使用了quickxml（较新版本）。

Pom：

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

代码：

 code> 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）; 
} 
 
} 
  

What I have:

I'm generating a JSON schema from a pojo. My code to generate the schema looks like so:

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

I'm generating several schemas via the above code. One of the pojos has an internal embedded enum to limit the possible values, like so:

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;
            }
        }

    }

}

The above code should limit the possible String values in the JSON data that's passed around to "Monday", "Tuesday", "Wednesday", etc.

When I run the schema generator on the code in question, I expect to get something like the following schema:

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

but instead I'm getting this:

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

I've done some digging in the Jackson Schema Module source code and figured out that what's happening is Jackson's using ".toString()" as the default serialization method for enum types, but what I need it to do instead is create the line that looks like this based on StartDayOfWeek.values():

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

Does anyone know how to do that?

解决方案

Storme's answer references org.codehaus, which is an older version of jackson. The following is similar but uses fasterxml (newer version).

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>

Code:

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);
    }

}

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