我有以下 json:
[
{
"type": 1,
"Steps": {
"steps": steps
}
},
{
"type": 2,
"HeartRate": {
"heartrates": heartRates
}
}
]
字段steps只是一个int,heartRates是一个int数组。我想要 使用 gson 将其解析为两个类。 我在stackoverflow上发现了类似的问题:How parse json array with multiple objects by gson?并尝试过,但没有成功。这是我的代码:
public class DataModels extends ArrayList<DataModels.Container> {
public class Container {
public int type;
public Object object;
}
public class Steps {
double steps;
public Steps(double steps) {
this.steps = steps;
}
public double getSteps() {
return steps;
}
@Override
public String toString() {
return "Steps: " + steps;
}
}
public class HeartRate {
int heartRate;
public HeartRate(int hr) {
heartRate = hr;
}
public double getHeartRate() {
return heartRate;
}
@Override
public String toString() {
return "Heart rate: " + heartRate;
}
}
}
然后解析我的 json:
public String getJSONMessage(String gearSData) {
System.out.println(gearSData);
Gson gson = new Gson();
DataModels model = gson.fromJson(gearSData, DataModels.class);
System.out.println(model);
for (DataModels.Container container: model) {
System.out.println(container.type);
System.out.println(container.object);
String innerJson = gson.toJson(container.object);
System.out.println("InnerJson: " + innerJson);
switch (container.type) {
case 1:
DataModels.Steps steps = gson.fromJson(innerJson, DataModels.Steps.class);
System.out.println(steps);
break;
case 2:
DataModels.HeartRate heartRate = gson.fromJson(innerJson, DataModels.HeartRate.class);
System.out.println(heartRate);
break;
}
}
}
类型被正确解析,但innerjson为空,我不知道为什么。有人可以解释一下吗?或者有人知道更好的方法吗?
最佳答案
字段名称应与 json 中的字段相同。我刚刚重命名了您的类的字段,您的代码对我来说效果很好:
public static String getJSONMessage(String gearSData) {
System.out.println(gearSData);
Gson gson = new Gson();
DataModels model = gson.fromJson(gearSData, DataModels.class);
System.out.println(model);
for (DataModels.Container container : model) {
System.out.println(container.type);
String innerJson = gson.toJson(container.type == 1 ? container.Steps : container.HeartRate);
System.out.println("InnerJson: " + innerJson);
//...
}
return null;
}
public static class DataModels extends ArrayList<DataModels.Container> {
public static class Container {
public int type;
public StepsType Steps; // object for type 1
public HeartRateType HeartRate; // object for type 2
}
public static class StepsType {
double steps;
//...
}
public static class HeartRateType {
int heartrates;
//...
}
}
关于java - 将具有不同对象的 json 数组解析为它们的类,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/35744791/