jackson2

问题 Given these classes: @Value private static class Message { private final String type; private final MyType message; } @Value public class MyType { private final String foo; } Jackson will produce: { "Type" : "Test", "Message" : {"foo" : "bar"} } Is there some type of annotation or instruction I can give to Jackson to ask it to serialize the nested complex type as a string, e.g. the desired JSON would be: { "Type" : "Test", "Message" : "{\"foo\" : \"bar\"}" } I tried both of these annotations

问题 Given these classes: @Value private static class Message { private final String type; private final MyType message; } @Value public class MyType { private final String foo; } Jackson will produce: { "Type" : "Test", "Message" : {"foo" : "bar"} } Is there some type of annotation or instruction I can give to Jackson to ask it to serialize the nested complex type as a string, e.g. the desired JSON would be: { "Type" : "Test", "Message" : "{\"foo\" : \"bar\"}" } I tried both of these annotations

问题 Given these classes: @Value private static class Message { private final String type; private final MyType message; } @Value public class MyType { private final String foo; } Jackson will produce: { "Type" : "Test", "Message" : {"foo" : "bar"} } Is there some type of annotation or instruction I can give to Jackson to ask it to serialize the nested complex type as a string, e.g. the desired JSON would be: { "Type" : "Test", "Message" : "{\"foo\" : \"bar\"}" } I tried both of these annotations

问题 Here is how I am trying to convert an object to json String ObjectNode batch = OBJECT_MAPPER.createObjectNode(); String s = OBJECT_MAPPER.writeValueAsString((triggerCommands.getCommands())); batch.put("commands", s); System.out.println("raw String= " + s); System.out.println("ObjectNode String = " + batch); Which results in output of; raw String= [{"cmdid":"a06c00d4-5b8b-4313-a8f3-5663dde0fa5b","type":"test"}] ObjectNode String = {"commands":"[{\"cmdid\":\"a06c00d4-5b8b-4313-a8f3-5663dde0fa5b

问题 I have a List in a Java Pojo class. That list contains some MyChildPojo objects which are not null but can have properties with null values. Example: MyChildPojo obj1 = new MyChildPojo(); MyChildPojo obj2 = new MyChildPojo(); I have added @JsonInclude(JsonInclude.Include.NON_EMPTY) on my MyChildPojo class so null properties will not be added while serializing the object. Now my final serialized output for the List object is: [ {}, {} ] I want to remove the complete List object in this case. I

问题 By default, Jackson is using java.util.ArrayList to deserialise a JSON array. Instead of this, I want to use a custom implementation. For example, Guava ImmutableList if value is present, or Collection.emptyList() if JSON array is empty or null. I want to configure this globally for ObjectMapper . Is there an easy way to do this? PS: My Jackson version is 2.9.7 回答1: General solution is to use custom module. You can define classes you would like to use for collections. For Guava there is a

问题 I've generated a Spring Boot web application using Spring Initializr, using embedded Tomcat + Thymeleaf template engine in a macOS Sierra., where I have to parse Json object I have a domain object with this property: @JsonProperty("activationTime") private BigInteger activationTime; But when I parse the object I this error: com.fasterxml.jackson.databind.JsonMappingException: Numeric value (1557587751202) out of range of int at [Source: {"data":[{"id":"18AE62","name":"Device 0018AE62","type":

问题 I've generated a Spring Boot web application using Spring Initializr, using embedded Tomcat + Thymeleaf template engine in a macOS Sierra., where I have to parse Json object I have a domain object with this property: @JsonProperty("activationTime") private BigInteger activationTime; But when I parse the object I this error: com.fasterxml.jackson.databind.JsonMappingException: Numeric value (1557587751202) out of range of int at [Source: {"data":[{"id":"18AE62","name":"Device 0018AE62","type":

问题 I've generated a Spring Boot web application using Spring Initializr, using embedded Tomcat + Thymeleaf template engine in a macOS Sierra., where I have to parse Json object I have a domain object with this property: @JsonProperty("activationTime") private BigInteger activationTime; But when I parse the object I this error: com.fasterxml.jackson.databind.JsonMappingException: Numeric value (1557587751202) out of range of int at [Source: {"data":[{"id":"18AE62","name":"Device 0018AE62","type":

问题 Consider json: { "name": "myName", "myNestedJson": "{\"key\":\"value\"}" } Should be parsed into classes: public class MyDto { String name; Attributes myNestedJson; } public class Attributes { String key; } Can it be parsed without writing stream parser? (Note that myNestedJson contains json escaped json string) 回答1: I think you can add a constructor to Attributes that takes a String class Attributes { String key; public Attributes() {} public Attributes(String s) { // Here, s is {"key":