The original link: http://www.dubby.cn/detail.html?id=9071
Field named
@JsonPropertyYou can specify the name of the field (you can also specify that the field needs to participate in serialization and deserialization).@JsonProperty.value: Specifies the field name@JsonProperty.index: Specifies the order, the write data format is based on the order (JSON is not this data format)@JsonProperty.defaultValue: Default value. Note: This property is not currently used by core and data-bind; Prepare some extension modules for use.
Field contains
@JsonAutoDetect: Defines the default field inclusion rules@JsonIgnore: Ignores a specified field:- Modifier fields, any one of the setters and getters, you add everything
- Unless you use
@JsonPropertyModifier, which can be implemented by ignoring only serialization or deserialization
- Unless you use
- Modifier fields, any one of the setters and getters, you add everything
@JsonIgnoreProperties: Decorates a class, specifying that a list of fields should be ignored or that unknown fields should be ignored@JsonIgnoreType: decorates a class, ignoring fields of the specified type@JsonInclude: Can define whether null values participate in (de-serialization)
Field documents, metadata
@JsonPropertyDescription:2.3 Support for configuring human reading interpretations for fields- This annotation is not used by core and data-bind, but is mainly used by the JSON Schema Generator module
Deserialization and serialization details
@JsonFormat: For Date/Time fields, you can specify a format@JsonUnwrapped: Specifies that a field (of type POJO) should be serialized into a flat rather than a nested object that will be wrapped into an object when deserialized@JsonView: Views can be defined
@jsonunwrapped (prefix = “pre”)
public class MyValue {
public String name;
JsonUnwrapped(prefix = "pre_", suffix = "_suf")
public MyValue myValue;
public int age;
public Date date;
}
Copy the codeSerialization results:
{"name":"Yang jeong"."pre_name_suf":null,"pre_age_suf": 0."pre_date_suf":null,"age": 24,"date":"2017-12-09"}
Copy the codeJsonView simple explanation:
public class JsonViewTest {
public static void main(String[] args) throws IOException {
ObjectMapper objectMapper = new ObjectMapper();
String json = "{\"username\":\"dubby.cn\",\"password\":\"123456\"}"; / / deserialization, use the view User User = objectMapper. ReaderWithView (User. UserWithoutPassword. Class). ForType (User. The class). ReadValue (json); System.out.println(user); user.password ="xxxx"; / / serialization, using views String result1 = objectMapper. WriterWithView (User. UserWithoutPassword. Class). WriteValueAsString (User); System.out.println(result1); String result2 = objectMapper.writerWithView(User.UserWithPassword.class).writeValueAsString(user); System.out.println(result2); } } class User { @JsonView({UserWithoutPassword.class}) public String username; @JsonView({UserWithPassword.class}) public String password; public interface UserWithPassword extends UserWithoutPassword { } public interface UserWithoutPassword { } @Override public StringtoString() {
return "User{" +
"username='" + username + '\'' + ", password='" + password + '\'' + '}'; }}Copy the codeDeserialization details
@JacksonInject: Indicates that the value of a field is injected, not extracted from JSON@JsonAnySetter: modifies a two-argument method. Any fields that are present in JSON but not in the object are passed to this method as (key,value)@JsonCreator: Previous articleCustom constructorIntroduced the@JsonSetterIs:@JsonPropertyAlternative notes to@JsonEnumDefaultValue: If an undefined enumeration value is encountered during deserialization, the default enumeration is assigned
JsonAnySetter simple explanation:
public class JsonAnySetterTest {
public static void main(String[] args) throws IOException {
String json = "{\"username\":\"dubby.cn\",\"password\":\"123456\",\"x-key\":\"xxx-value\",\"y-key\":\"yyy-value\"}";
ObjectMapper objectMapper = new ObjectMapper();
Data data = objectMapper.readValue(json, Data.class);
System.out.println(data);
}
}
class Data {
public String username;
public String password;
public String other;
@JsonAnySetter
public void anySetter(String a, String b) {
if (other == null) {
other = "";
}
other += a;
other += ",";
other += b;
other += ";";
}
@Override
public String toString() {
return "Data{" +
"username='" + username + '\'' + ", password='" + password + '\'' + ", other='" + other + '\' ' +
'} '; }}Copy the codeOutput:
Data{username='dubby.cn', password='123456', other='x-key,xxx-value; y-key,yyy-value; '}
Copy the code@jsonEnumDefaultValue
public class EnumTest {
public static void main(String[] args) throws IOException {
ObjectMapper objectMapper = new ObjectMapper();
objectMapper.configure(DeserializationFeature.READ_UNKNOWN_ENUM_VALUES_USING_DEFAULT_VALUE, true);
String json = "{\"myEnum\":\"V4\"}";
EnumData enumData = objectMapper.readValue(json, EnumData.class);
System.out.println(enumData);
}
}
class EnumData {
public MyEnum myEnum;
@Override
public String toString() {
return "EnumData{" +
"myEnum=" + myEnum +
'} ';
}
}
enum MyEnum {
V1, V2, V3, @JsonEnumDefaultValue Default;
}
Copy the codeOutput:
EnumData{myEnum=Default}
Copy the codeSerialization details
@JsonAnyGetter: Decorates a method, returnsMapThe return value of this method is serialized into the (key,value) form@JsonGetter:@JsonPropertAlternative notes to@JsonPropertyOrder: Determines the serialization order@JsonRawValue: The fields to be decorated appear “exactly”, without escaping or decorating, and without double quotes@JsonValue: Specifies the serialized output value@JsonRootName: Uses the specified value as the root of the JSON, provided thatSerializationFeature.WRAP_ROOT_VALUEIt’s already open
JsonAnyGetter simple explanation:
public class JsonAnyGetterTest {
public static void main(String[] args) throws JsonProcessingException {
ObjectMapper objectMapper = new ObjectMapper();
AnyGetterData data = new AnyGetterData();
data.data = "http://dubby.cn";
System.out.println(objectMapper.writeValueAsString(data));
}
}
class AnyGetterData {
public String data;
@JsonAnyGetter
public Map other() {
Map<String, String> map = new HashMap<>();
map.put("key1"."value1");
map.put("key2"."value2");
map.put("key3"."value3");
returnmap; }}Copy the codeOutput:
{"data":"http://dubby.cn"."key1":"value1"."key2":"value2"."key3":"value3"}
Copy the code@jsonPropertyOrder
public class JsonPropertyOrderTest {
public static void main(String[] args) throws JsonProcessingException {
ObjectMapper objectMapper = new ObjectMapper();
JsonPropertyOrderData data = new JsonPropertyOrderData();
data.name1 = "value1";
data.name2 = "value3";
data.name3 = "value4";
System.out.println(objectMapper.writeValueAsString(data));
}
}
@JsonPropertyOrder(value = {"name2"."name3"."name1"})
class JsonPropertyOrderData {
public String name1;
public String name2;
public String name3;
}
Copy the codeOutput:
{"name2":"value3"."name3":"value4"."name1":"value1"}
Copy the code@jsonValue
public class JsonValueTest { public static void main(String[] args) throws IOException { ObjectMapper objectMapper = new ObjectMapper(); String json ="{\"name2\":\"value3\",\"name3\":\"value4\",\"name1\":\"value1\"}";
JsonValueData data = objectMapper.readValue(json, JsonValueData.class);
System.out.println(data.toString());
System.out.println(objectMapper.writeValueAsString(data));
}
}
class JsonValueData {
public String name1;
public String name2;
public String name3;
@JsonValue
public String other() {
return name1+name2+name3;
}
@Override
public String toString() {
return "JsonValueData{" +
"name1='" + name1 + '\'' + ", name2='" + name2 + '\'' + ", name3='" + name3 + '\' ' +
'} '; }}Copy the codeOutput:
JsonValueData{name1='value1', name2='value3', name3='value4'}
"value1value3value4"
Copy the code@jsonRootName
public class JsonRootNameTest {
public static void main(String[] args) throws JsonProcessingException {
ObjectMapper objectMapper = new ObjectMapper();
objectMapper.configure(SerializationFeature.WRAP_ROOT_VALUE, true);
RootData data = new RootData();
data.name1 = "value1";
data.name2 = "value2";
data.name3 = "value3";
System.out.println(objectMapper.writeValueAsString(data));
}
}
@JsonRootName(value = "root")
class RootData {
public String name1;
public String name2;
public String name3;
}
Copy the codeOutput:
{"root": {"name1":"value1"."name2":"value2"."name3":"value3"}}
Copy the code