Java 将JSON字符串反序列化为POJO列表
以下是我的代码,用于反序列化从Google App Engine云端点返回的响应:Java 将JSON字符串反序列化为POJO列表,java,json,google-app-engine,jackson,google-cloud-endpoints,Java,Json,Google App Engine,Jackson,Google Cloud Endpoints,以下是我的代码,用于反序列化从Google App Engine云端点返回的响应: String jsonString = IOUtils.toString( httpResponse.getEntity().getContent(), "UTF-8"); ObjectMapper mapper = new ObjectMapper(); ArrayList<myPOJO> myList= mapper.readValue(jsonString, new Type
String jsonString = IOUtils.toString(
httpResponse.getEntity().getContent(), "UTF-8");
ObjectMapper mapper = new ObjectMapper();
ArrayList<myPOJO> myList=
mapper.readValue(jsonString, new TypeReference<ArrayList<MyPOJO>>(){});
但我得到了这个错误:
org.codehaus.jackson.map.JsonMappingException: Can not deserialize instance of java.util.ArrayList out of START_OBJECT token at [Source: java.io.StringReader@547a7880; line: 1, column: 1]
使用Jackson将此JSON反序列化为POJO列表的正确方法是什么?尝试直接使用映射器反序列化
String jsonString = IOUtils.toString(
httpResponse.getEntity().getContent(), "UTF-8");
ObjectMapper mapper = new ObjectMapper();
List<MyPOJO> myList= mapper.convertValue(jsonString, mapper.getTypeFactory().constructCollectionType(List.class, MyPOJO.class));
String jsonString=IOUtils.toString(
httpResponse.getEntity().getContent(),“UTF-8”);
ObjectMapper mapper=新的ObjectMapper();
List myList=mapper.convertValue(jsonString,mapper.getTypeFactory().constructionCollectionType(List.class,MyPOJO.class));
您必须为JSON
根对象创建根POJO
。例如:
class Root {
private List<Entity> items;
//getters, setters, toString, etc
}
class Entity {
private long id;
private String name;
//getters, setters, toString, etc
}
印刷品:
Root [items=[Entity [id=12345, name=test1], Entity [id=121212, name=test2]]]
您的jsonString是一个对象,而不是列表。您可以使用jackson库来实现此目的。这不起作用。错误仅更改为
,原因是:org.codehaus.jackson.map.JsonMappingException:无法反序列化java.util.ArrayList的实例超出值\u字符串标记
ObjectMapper mapper = new ObjectMapper();
Root list = mapper.readValue(json, Root.class);
System.out.println(list);
Root [items=[Entity [id=12345, name=test1], Entity [id=121212, name=test2]]]