@JsonProperty
可以指定字段的命名(还可以指定这个字段需要参与序列化和反序列化)。 @JsonProperty.value @JsonProperty.index @JsonProperty.defaultValue
@JsonAutoDetect
:定义默认的字段包含规则 @JsonIgnore
:忽略某个指定的字段: @JsonProperty
修饰,可以实现只忽略序列化或者反序列化 @JsonIgnoreProperties
:修饰类,指定忽略一个字段列表,或者忽略那些未知的字段 @JsonIgnoreType
:修饰类,忽略指定的类型的字段 @JsonInclude
:可以定义空值是否参与(反)序列化 @JsonPropertyDescription
:2.3支持,给字段配置人类阅读的解释 @JsonFormat @JsonUnwrapped @JsonView
@JsonUnwrapped(prefix = "pre")
简单解释:
public class MyValue { public String name; JsonUnwrapped(prefix = "pre_", suffix = "_suf") public MyValue myValue; public int age; public Date date; } 复制代码
序列化结果:
{"name":"杨正","pre_name_suf":null,"pre_age_suf":0,"pre_date_suf":null,"age":24,"date":"2017-12-09"} 复制代码
@JsonView
简单解释:
public class JsonViewTest { public static void main(String[] args) throws IOException { ObjectMapper objectMapper = new ObjectMapper(); String json = "{/"username/":/"dubby.cn/",/"password/":/"123456/"}"; //反序列化,使用视图 User user = objectMapper.readerWithView(User.UserWithoutPassword.class).forType(User.class).readValue(json); System.out.println(user); user.password = "xxxx"; //序列化,使用视图 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 String toString() { return "User{" + "username='" + username + '/'' + ", password='" + password + '/'' + '}'; } } 复制代码
@JacksonInject
:指示某个字段的值是注入的,而不是从JSON中取出的 @JsonAnySetter
:修饰一个2个参数的方法,任何JSON中有,而对象中没有的字段都会以(key,value)的形式传给这个方法 @JsonCreator
:上篇文章自定义构造方法介绍过了 @JsonSetter
:是 @JsonProperty
的替代注解 @JsonEnumDefaultValue
:反序列化时,如果遇到未定义的枚举值时,赋值为默认枚举
@JsonAnySetter
简单解释:
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 + '/'' + '}'; } } 复制代码
输出:
Data{username='dubby.cn', password='123456', other='x-key,xxx-value;y-key,yyy-value;'} 复制代码
@JsonEnumDefaultValue
简单解释:
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; } 复制代码
输出:
EnumData{myEnum=Default} 复制代码
@JsonAnyGetter
:修饰一个方法,返回 Map
,这个方法的返回值会被序列化成(key,value)形式 @JsonGetter
: @JsonPropert
的替代注解 @JsonPropertyOrder
:注定序列化的顺序 @JsonRawValue
:被修饰的字段“准确”的显示出来,没有转义或装饰,双引号都不加 @JsonValue
:指定序列化输出的值 @JsonRootName
:使用这个指定的值作为JSON的根,前提是 SerializationFeature.WRAP_ROOT_VALUE
已经打开了
@JsonAnyGetter
简单解释:
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"); return map; } } 复制代码
输出:
{"data":"http://dubby.cn","key1":"value1","key2":"value2","key3":"value3"} 复制代码
@JsonPropertyOrder
简单解释:
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; } 复制代码
输出:
{"name2":"value3","name3":"value4","name1":"value1"} 复制代码
@JsonValue
简单解释:
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 + '/'' + '}'; } } 复制代码
输出:
JsonValueData{name1='value1', name2='value3', name3='value4'} "value1value3value4" 复制代码
@JsonRootName
简单解释:
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; } 复制代码
输出:
{"root":{"name1":"value1","name2":"value2","name3":"value3"}} 复制代码