我需要将某个JSON字符串转换为Java对象。我正在使用Jackson进行JSON处理。我无法控制输入JSON(我从web服务读取)。这是我的输入JSON:
{"wrapper":[{"id":"13","name":"Fred"}]}
下面是一个简化的用例:
private void tryReading() {
String jsonStr = "{\"wrapper\"\:[{\"id\":\"13\",\"name\":\"Fred\"}]}";
ObjectMapper mapper = new ObjectMapper();
Wrapper wrapper = null;
try {
wrapper = mapper.readValue(jsonStr , Wrapper.class);
} catch (Exception e) {
e.printStackTrace();
}
System.out.println("wrapper = " + wrapper);
}
我的实体类是:
public Class Student {
private String name;
private String id;
//getters & setters for name & id here
}
我的Wrapper类基本上是一个容器对象来获取我的学生列表:
public Class Wrapper {
private List<Student> students;
//getters & setters here
}
我一直得到这个错误和“包装器”返回null。我不知道少了什么。有人能帮帮我吗?
org.codehaus.jackson.map.exc.UnrecognizedPropertyException:
Unrecognized field "wrapper" (Class Wrapper), not marked as ignorable
at [Source: java.io.StringReader@1198891; line: 1, column: 13]
(through reference chain: Wrapper["wrapper"])
at org.codehaus.jackson.map.exc.UnrecognizedPropertyException
.from(UnrecognizedPropertyException.java:53)
我已经尝试了下面的方法，它适用于这样的JSON格式读取杰克逊。
使用已经建议的解决方案:用@JsonProperty("wrapper")注释getter
你的包装类
public Class Wrapper{
private List<Student> students;
//getters & setters here
}
我对包装类的建议
public Class Wrapper{
private StudentHelper students;
//getters & setters here
// Annotate getter
@JsonProperty("wrapper")
StudentHelper getStudents() {
return students;
}
}
public class StudentHelper {
@JsonProperty("Student")
public List<Student> students;
//CTOR, getters and setters
//NOTE: If students is private annotate getter with the annotation @JsonProperty("Student")
}
然而，这将为您提供格式的输出:
{"wrapper":{"student":[{"id":13,"name":Fred}]}}
更多信息请访问https://github.com/FasterXML/jackson-annotations
我已经尝试了下面的方法，它适用于这样的JSON格式读取杰克逊。
使用已经建议的解决方案:用@JsonProperty("wrapper")注释getter
你的包装类
public Class Wrapper{
private List<Student> students;
//getters & setters here
}
我对包装类的建议
public Class Wrapper{
private StudentHelper students;
//getters & setters here
// Annotate getter
@JsonProperty("wrapper")
StudentHelper getStudents() {
return students;
}
}
public class StudentHelper {
@JsonProperty("Student")
public List<Student> students;
//CTOR, getters and setters
//NOTE: If students is private annotate getter with the annotation @JsonProperty("Student")
}
然而，这将为您提供格式的输出:
{"wrapper":{"student":[{"id":13,"name":Fred}]}}
更多信息请访问https://github.com/FasterXML/jackson-annotations
