Android：Gson将整数反序列化为双精度 [英] Android: Gson deserializes Integer as Double
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问题描述
我试图使用这个库
I am trying websockets on android using this library WebSocketRails-Android but I want to replace Jackson with Google's Gson but I am having a problem on deserialization. So on receiving a JSON string like this
[["websocket_rails.subscribe",{"id":1676395261,"channel":null,"user_id":null,"data":{"message":"Connected successfully to 82c6"},"success":true,"result":null,"token":null,"server_token":null}]]
Gson deserializes it and gives me the id = 1.676395261E9
I am deserializing like this
@Override
public void onStringAvailable(String data) {
Gson gson = new Gson();
Type type = new TypeToken<List>() {}.getType();
List<Object> list;
list = gson.fromJson(data, type);
...
}
Any help would be appreciated
UPDATE: Endend up creating a function converting that double id to an int. Thanks for your answers though.
解决方案
I had the same problem. Try this :
public final class Values {
static final Map<Class<?>, Object> defaultValues = new HashMap();
// load
static {
defaultValues.put(boolean.class, Boolean.FALSE);
defaultValues.put(byte.class, (byte) 0);
defaultValues.put(short.class, (short) 0);
defaultValues.put(int.class, 0);
defaultValues.put(long.class, 0L);
defaultValues.put(char.class, '\0');
defaultValues.put(float.class, 0.0F);
defaultValues.put(double.class, 0.0);
defaultValues.put(Boolean.class, Boolean.FALSE);
defaultValues.put(Byte.class, (byte) 0);
defaultValues.put(Short.class, (short) 0);
defaultValues.put(Integer.class, 0);
defaultValues.put(Long.class, 0L);
defaultValues.put(Character.class, '\0');
defaultValues.put(Float.class, 0.0F);
defaultValues.put(Double.class, 0.0);
}
public static final <T> T defaultValueFor(Class<T> clazz) {
if (!defaultValues.containsKey(clazz)) return null;
return (T) defaultValues.get(clazz);
}
}
public class ObjectAdapter implements JsonDeserializer<java.lang.Object>, InstanceCreator<java.lang.Object>, JsonSerializer<java.lang.Object> {
@Override
public Object createInstance(Type type) {
Object result = null;
Constructor c = null;
final Class clazz;
if (type instanceof ParameterizedType) {
clazz = (Class) TypeToken.getParameterized(((ParameterizedType) type).getRawType(), ((ParameterizedType) type).getActualTypeArguments()).getRawType();
} else {
clazz = (Class) type;
}
for (Constructor construtor : clazz.getConstructors()) {
if (c == null || c.getParameterTypes().length > construtor.getParameterTypes().length)
c = construtor;
}
try {
if (c != null && c.getParameterTypes().length > 0) {
Object[] param = new Object[c.getParameterTypes().length];
boolean b = c.isAccessible();
c.setAccessible(true);
for (int index = 0; index < c.getParameterTypes().length; index++) {
if (c.getParameterTypes()[index].isPrimitive()) {
if (long.class.isAssignableFrom(c.getParameterTypes()[index]) || int.class.isAssignableFrom(c.getParameterTypes()[index]) ||
short.class.isAssignableFrom(c.getParameterTypes()[index]) || byte.class.isAssignableFrom(c.getParameterTypes()[index]) ||
float.class.isAssignableFrom(c.getParameterTypes()[index]) || double.class.isAssignableFrom(c.getParameterTypes()[index]))
param[index] = 0;
else if (char.class.isAssignableFrom(c.getParameterTypes()[index]))
param[index] = '\u0000';
else if (boolean.class.isAssignableFrom(c.getParameterTypes()[index]))
param[index] = false;
else
throw new RuntimeException(c.getTypeParameters()[index].getName());
} else if (!Object.class.equals(c.getParameterTypes()[index])) {
param[index] = Values.defaultValueFor(c.getParameterTypes()[index]);
} else
param[index] = null;
}
result = c.newInstance(param);
c.setAccessible(b);
} else if (c != null) {
result = c.newInstance();
}
} catch (IllegalAccessException e) {
e.printStackTrace();
throw new RuntimeException(e);
} catch (InstantiationException e) {
e.printStackTrace();
throw new RuntimeException(e);
} catch (InvocationTargetException e) {
e.printStackTrace();
throw new RuntimeException(e);
}
return result;
}
@Override
public Object deserialize(JsonElement json, Type typeOfT, JsonDeserializationContext context) throws JsonParseException {
Object result;
if (json.isJsonObject()) {
result = this.createInstance(typeOfT);
final JsonObject jsonO = json.getAsJsonObject();
try {
Class c = (Class) typeOfT;
do {
for (final Field field : c.getDeclaredFields()) {
if (!Modifier.isTransient(field.getModifiers()) && (!Modifier.isFinal(field.getModifiers()) && !Modifier.isStatic(field.getModifiers()))) {
String name = field.getType().getName() + "." + field.getName();
if (!jsonO.has(name))
name = field.getName();
Class type;
if (field.getGenericType() instanceof ParameterizedType) {
type = TypeToken.getParameterized(((ParameterizedType) field.getGenericType()).getRawType(), ((ParameterizedType) field.getGenericType()).getActualTypeArguments()).getRawType();
} else {
type = TypeToken.get(field.getType()).getRawType();
}
final boolean b = field.isAccessible();
field.setAccessible(true);
JsonElement element = jsonO.get(name);
if (String.class.isAssignableFrom(type))
field.set(result, element.getAsString());
else if (element.isJsonArray())
field.set(result, context.deserialize(element.getAsJsonArray(), type));
else if (java.lang.Object.class.isAssignableFrom(type) && !element.isJsonPrimitive())
field.set(result, context.deserialize(element.getAsJsonObject(), type));
else if (Serializable.class.isAssignableFrom(type) && element.isJsonPrimitive())
field.set(result, context.deserialize(element, type));
else
field.set(result, context.deserialize(element, type));
field.setAccessible(b);
}
}
} while ((c = c.getSuperclass()) != null);
} catch (IllegalAccessException e) {
e.printStackTrace();
throw new RuntimeException(e);
}
} else if (json.isJsonPrimitive()) {
final JsonPrimitive jsonP = json.getAsJsonPrimitive();
if (Long.class.isAssignableFrom((Class) typeOfT))
result = jsonP.getAsLong();
else if (Integer.class.isAssignableFrom((Class) typeOfT))
result = jsonP.getAsInt();
else if (Short.class.isAssignableFrom((Class) typeOfT))
result = jsonP.getAsShort();
else if (Byte.class.isAssignableFrom((Class) typeOfT))
result = jsonP.getAsByte();
else if (Double.class.isAssignableFrom((Class) typeOfT))
result = jsonP.getAsDouble();
else if (Float.class.isAssignableFrom((Class) typeOfT)) {
result = jsonP.getAsFloat();
} else if (Character.class.isAssignableFrom((Class) typeOfT)) {
result = jsonP.getAsCharacter();
} else if (Boolean.class.isAssignableFrom((Class) typeOfT))
result = jsonP.getAsBoolean();
else if (String.class.isAssignableFrom(((Class) typeOfT)))
result = jsonP.getAsString();
else
throw new JsonParseException("Primitive is not supported");
} else
throw new JsonParseException("json is not a json Object");
return result;
}
@Override
public JsonElement serialize(Object src, Type typeOfSrc, JsonSerializationContext context) {
final JsonElement result;
if (Long.class.isAssignableFrom((Class) typeOfSrc) || Integer.class.isAssignableFrom((Class) typeOfSrc) || Short.class.isAssignableFrom((Class) typeOfSrc) ||
Byte.class.isAssignableFrom((Class) typeOfSrc) || Double.class.isAssignableFrom((Class) typeOfSrc) || Float.class.isAssignableFrom((Class) typeOfSrc)) {
result = new JsonPrimitive((Number) src);
} else if (Character.class.isAssignableFrom((Class) typeOfSrc)) {
result = new JsonPrimitive((Character) src);
} else if (Boolean.class.isAssignableFrom((Class) typeOfSrc))
result = new JsonPrimitive((Boolean) src);
else if (String.class.isAssignableFrom((Class) typeOfSrc))
result = new JsonPrimitive((String) src);
else if (Arrays.class.isAssignableFrom((Class) typeOfSrc) || ArrayList.class.isAssignableFrom((Class) typeOfSrc)) {
result = new JsonArray();
if (Arrays.class.isAssignableFrom((Class) typeOfSrc)) {
for (Object object : Arrays.asList((Object[]) src)) {
if (Long.class.isAssignableFrom(object.getClass()) || Integer.class.isAssignableFrom(object.getClass()) || Short.class.isAssignableFrom(object.getClass()) ||
Byte.class.isAssignableFrom(object.getClass()) || Double.class.isAssignableFrom(object.getClass()) || Float.class.isAssignableFrom(object.getClass())) {
((JsonArray) result).add((Number) object);
} else if (Character.class.isAssignableFrom(object.getClass())) {
((JsonArray) result).add((Character) object);
} else if (Boolean.class.isAssignableFrom(object.getClass()))
((JsonArray) result).add((Boolean) object);
else if (String.class.isAssignableFrom(object.getClass()))
((JsonArray) result).add((String) object);
else {
TypeVariable type = ((Class<ArrayList>) typeOfSrc).getTypeParameters()[0];
((JsonArray) result).add(context.serialize(object, type));
}
}
} else {
ArrayList iterable = (ArrayList) src;
for (Object object : iterable) {
Class c = object.getClass();
if (Long.class.isAssignableFrom(object.getClass()) || Integer.class.isAssignableFrom(object.getClass()) || Short.class.isAssignableFrom(object.getClass()) ||
Byte.class.isAssignableFrom(object.getClass()) || Double.class.isAssignableFrom(object.getClass()) || Float.class.isAssignableFrom(object.getClass())) {
((JsonArray) result).add((Number) object);
} else if (Character.class.isAssignableFrom(object.getClass())) {
((JsonArray) result).add((Character) object);
} else if (Boolean.class.isAssignableFrom(object.getClass()))
((JsonArray) result).add((Boolean) object);
else if (String.class.isAssignableFrom(object.getClass()))
((JsonArray) result).add((String) object);
else
((JsonArray) result).add(context.serialize(object, object.getClass()));
}
}
} else {
result = new JsonObject();
Class c = src.getClass();
do {
for (Field field : c.getDeclaredFields()) {
if (!Modifier.isTransient(field.getModifiers()) && (!Modifier.isFinal(field.getModifiers()) && !Modifier.isStatic(field.getModifiers()))) {
final boolean b = field.isAccessible();
field.setAccessible(true);
String name = field.getName();
if (((JsonObject) result).has(name))
name = field.getType().getName() + "." + field.getName();
final Class type;
if (field.getGenericType() instanceof ParameterizedType) {
type = TypeToken.getParameterized(((ParameterizedType) field.getGenericType()).getRawType(), ((ParameterizedType) field.getGenericType()).getActualTypeArguments()).getRawType();
} else {
type = TypeToken.get(field.getType()).getRawType();
}
try {
if (type.isPrimitive()) {
if (Number.class.isAssignableFrom(type))
((JsonObject) result).addProperty(name, (Number) field.get(src));
else if (Character.class.isAssignableFrom(type))
((JsonObject) result).addProperty(name, (Character) field.get(src));
else if (Boolean.class.isAssignableFrom(type))
((JsonObject) result).addProperty(name, (Boolean) field.get(src));
else
((JsonObject) result).addProperty(name, (field.get(src) != null) ? String.valueOf(field.get(src)) : null);
} else if (String.class.isAssignableFrom(type))
((JsonObject) result).addProperty(name, (field.get(src) != null) ? String.valueOf(field.get(src)) : null);
else if (Number.class.isAssignableFrom(type))
((JsonObject) result).addProperty(name, (Number) field.get(src));
else if (Character.class.isAssignableFrom(type))
((JsonObject) result).addProperty(name, (Character) field.get(src));
else if (Boolean.class.isAssignableFrom(type))
((JsonObject) result).addProperty(name, (Boolean) field.get(src));
else
((JsonObject) result).add(name, context.serialize(field.get(src), type));
} catch (IllegalAccessException e) {
e.printStackTrace();
throw new RuntimeException(e);
}
field.setAccessible(b);
}
}
} while ((c = c.getSuperclass()) != null);
}
return result;
}
}
And this :
List<Object> list = new GsonBuilder().registerTypeHierarchyAdapter(java.lang.Object.class, new ObjectAdapter()).create().fromJson(data, type);
这篇关于Android：Gson将整数反序列化为双精度的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
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