将json字符串映射到模型类对象时出错

Question

下面是我要读取并映射到类模型对象的 json。

{
    "models": [
        {
            "model": {
                "code": "YY77A",
                "type": "AUTO",
                "source": "IN",
                "name": "Sams",
                "feature_types": [
                    {
                        "feature_type": {
                            "code": "8H",
                            "desc": "All Models"
                        }
                    },
                    {
                        "feature_type": {
                            "code": "my20",
                            "desc": "MY20"
                        }
                    },
                    {
                        "feature_type": {
                            "code": "my21",
                            "desc": "MY21"
                        }
                    }
                ]
            }
        },
        {
            "model": {
                "code": "PPuY",
                "type": "HOM",
                "source": "IN",
                "name": null,
                "feature_types": [
                    {
                        "feature_type": {
                            "code": "8H",
                            "desc": "All Models"
                        }
                    },
                    {
                        "feature_type": {
                            "code": "MY21",
                            "desc": "MY21"
                        }
                    }
                ]
            }
        }
    ]
}

模型类：

class FeatureType2{
    public String code;
    public String desc;
}

class FeatureType{
    public FeatureType feature_type;
}

class Model2{
    public String code;
    public String type;
    public String source;
    public String name;
    public List<FeatureType> feature_types;
}

class Model{
    public Model model;
}

public class Root{
    public List<Model> models;
}

以下是用于将 json 映射到模型 (Root.java) 的代码

// import com.fasterxml.jackson.databind.ObjectMapper; // version 2.11.1
// import com.fasterxml.jackson.annotation.JsonProperty; // version 2.11.1
ObjectMapper om = new ObjectMapper();
Root root = om.readValue(myJsonString), Root.class);  

以下是例外：

com.fasterxml.jackson.databind.exc.UnrecognizedPropertyException: Unrecognized field "code" (
com.fasterxml.jackson.databind.exc.UnrecognizedPropertyException: Unrecognized field "code" (class com.samp.qc.Model), not marked as ignorable (one known property: "model"])
at [Source: java.io.StringReader@15f53014; line: 1, column: 30] (through reference chain: com.samp.qc.Root["models"]->
com.samp.qc.Model["model"]->com.samp.qc.Model["code"])

当将 json 字符串映射到模型对象时，它会显示上述异常。将 json String 映射到 Model 类对象的更好方法是什么。

Answer 1

您在 Model & FeatureType 类中犯了小错误。我更正如下，它对我有用。

    public class FeatureType2{
        public String code;
        public String desc;
    }

    public class FeatureType{
        public FeatureType2 feature_type;
    }

    public class Model2{
        public String code;
        public String type;
        public String source;
        public String name;
        public List<FeatureType> feature_types;
    }

    public class Model{
        public Model2 model;
    }

    public class Root{
        public List<Model> models;
    }

如果这能解决您的问题，请告诉我。