如何忽略杰克逊JSON到对象映射中的枚举字段？

我认为您应该为枚举定义外部解串器

Grade

我在枚举中添加了其他字段-未知：

enum Grade {    A, B, C, UNKNOWN;    public static Grade fromString(String value) {        for (Grade grade : values()) { if (grade.name().equalsIgnoreCase(value)) {     return grade; }        }        return UNKNOWN;    }}class Employee {    @JsonDeserialize(using = GradeDeserializer.class)    private Grade grade;    private String name;    public Grade getGrade() {        return grade;    }    public void setGrade(Grade grade) {        this.grade = grade;    }    public String getName() {        return name;    }    public void setName(String name) {        this.name = name;    }    @Override    public String toString() {        return "Employee [grade=" + grade + ", name=" + name + "]";    }}

现在，解析器可能看起来像这样：

class GradeDeserializer extends JsonDeserializer<Grade> {    @Override    public Grade deserialize(JsonParser parser, DeserializationContext context) throws IOException, JsonProcessingException {        return Grade.fromString(parser.getValueAsString());    }}

用法示例：

public class JacksonProgram {    public static void main(String[] args) throws Exception {        ObjectMapper objectMapper = new ObjectMapper();        JsonFactory jsonFactory = new JsonFactory();        JsonParser parser = jsonFactory     .createJsonParser("{"name":"John", "grade":"D"}");        Employee employee = objectMapper.readValue(parser, Employee.class);        System.out.println(employee);    }}

输出：

Employee [grade=UNKNOWN, name=John]

如果您不想添加其他字段，则返回

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