I got an json array from server response:
[{"id":1, "name":"John", "age": 20},{"id":3, "name":"Tomas", "age": 29}, {"id":12, "name":"Kate", "age": 32}, ...]
I would like to use gson to convert the above json data to a Java List<Person> object. I tried the following way:
Firstly, I created a Person.java class:
public class Person{
private long id;
private String name;
private int age;
public long getId(){
return id;
}
public String getName(){
return name;
}
public int getAge(){
return age;
}
}
Then, in my service class, I did the following:
//'response' is the above json array
List<Person> personList = gson.fromJson(response, List.class);
for(int i=0; i<personList.size(); i++){
Person p = personList.get(i); //java.lang.ClassCastException: java.util.LinkedHashMap cannot be cast to Person
}
I got Exception java.lang.ClassCastException: java.util.LinkedHashMap cannot be cast to Person . How to get rid of my problem? I just want to convert the json array to a List<Person> object. Any help?
You need to use a supertype token for the unmarshalling, so that Gson knows what the generic type in your list is. Try this:
TypeToken<List<Person>> token = new TypeToken<List<Person>>(){};
List<Person> personList = gson.fromJson(response, token.getType());
And iterate through the results as such:
for(Person person : personList) {
// some code here
}
Collected from the Internet
Please contact [email protected] to delete if infringement.
Comments