Android GSON自定义反序列化程序处理Null
我为android.net.Uri编写了一个定制的GSON类型适配器：Android GSON自定义反序列化程序处理Null,android,json,gson,json-deserialization,Android,Json,Gson,Json Deserialization,我为android.net.Uri编写了一个定制的GSON类型适配器： public class UriAdpter extends TypeAdapter<Uri> { @Override public void write(JsonWriter out, Uri value) throws IOException { out.value(value.toString()); } @Override public Uri
public class UriAdpter extends TypeAdapter<Uri> {
@Override
public void write(JsonWriter out, Uri value) throws IOException {
out.value(value.toString());
}
@Override
public Uri read(JsonReader in) throws IOException {
return Uri.parse(in.nextString());
}
}
是否为null
，但这不起作用，因为.nextString（）中的引发异常，而不是Uri.parse（）
。在使用GSON进行反序列化时，如何检查null
对象？您尝试过使用吗
public类UriAdpter扩展了TypeAdapter{
@凌驾
public void write（JsonWriter out，Uri值）抛出IOException{
out.value（value.toString（））；
}
@凌驾
公共Uri读取（JsonReader in）引发IOException{
if（in.peek（）==JsonToken.NULL）{
in.nextNull（）；
返回null；
}
返回Uri.parse（in.nextString（））；
}
}
Hm，现在我得到一个不同的JsonSyntaxException
需要一个名称，但在第1行第23588列路径$.data[5]处为空。缩略图
。啊，不，没有找到.nextNull（）中的。修好了，谢谢！
03-30 08:40:00.799 16340-16340/com.example.app D/NewsFragment: Failed to retrieve articles
com.google.gson.JsonSyntaxException: java.lang.IllegalStateException: Expected a string but was NULL at line 1 column 23588 path $.data[5].thumbnail
at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory$Adapter.read(ReflectiveTypeAdapterFactory.java:220)
at com.google.gson.internal.bind.TypeAdapterRuntimeTypeWrapper.read(TypeAdapterRuntimeTypeWrapper.java:40)
at com.google.gson.internal.bind.CollectionTypeAdapterFactory$Adapter.read(CollectionTypeAdapterFactory.java:82)
at com.google.gson.internal.bind.CollectionTypeAdapterFactory$Adapter.read(CollectionTypeAdapterFactory.java:61)
at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory$1.read(ReflectiveTypeAdapterFactory.java:116)
at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory$Adapter.read(ReflectiveTypeAdapterFactory.java:216)
at retrofit2.converter.gson.GsonResponseBodyConverter.convert(GsonResponseBodyConverter.java:37)
at retrofit2.converter.gson.GsonResponseBodyConverter.convert(GsonResponseBodyConverter.java:25)
at retrofit2.ServiceMethod.toResponse(ServiceMethod.java:116)
at retrofit2.OkHttpCall.parseResponse(OkHttpCall.java:211)
at retrofit2.OkHttpCall.execute(OkHttpCall.java:174)
at retrofit2.adapter.rxjava.RxJavaCallAdapterFactory$CallOnSubscribe.call(RxJavaCallAdapterFactory.java:144)
at retrofit2.adapter.rxjava.RxJavaCallAdapterFactory$CallOnSubscribe.call(RxJavaCallAdapterFactory.java:125)
at rx.Observable$2.call(Observable.java:162)
at rx.Observable$2.call(Observable.java:154)
at rx.Observable$2.call(Observable.java:162)
at rx.Observable$2.call(Observable.java:154)
at rx.Observable.unsafeSubscribe(Observable.java:8314)
at rx.internal.operators.OperatorSubscribeOn$1.call(OperatorSubscribeOn.java:94)
at rx.internal.schedulers.ScheduledAction.run(ScheduledAction.java:55)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:423)
at java.util.concurrent.FutureTask.run(FutureTask.java:237)
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:269)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1113)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:588)
at java.lang.Thread.run(Thread.java:818)
Caused by: java.lang.IllegalStateException: Expected a string but was NULL at line 1 column 23588 path $.data[5].thumbnail
at com.google.gson.stream.JsonReader.nextString(JsonReader.java:830)
at com.example.app.data.rest.adapter.UriAdapter.read(UriAdapter.java:26)
at com.example.app.data.rest.adapter.UriAdapter.read(UriAdapter.java:16)
at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory$1.read(ReflectiveTypeAdapterFactory.java:116)
at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory$Adapter.read(ReflectiveTypeAdapterFactory.java:216)
at com.google.gson.internal.bind.TypeAdapterRuntimeTypeWrapper.read(TypeAdapterRuntimeTypeWrapper.java:40)
at com.google.gson.internal.bind.CollectionTypeAdapterFactory$Adapter.read(CollectionTypeAdapterFactory.java:82)
at com.google.gson.internal.bind.CollectionTypeAdapterFactory$Adapter.read(CollectionTypeAdapterFactory.java:61)
at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory$1.read(ReflectiveTypeAdapterFactory.java:116)
at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory$Adapter.read(ReflectiveTypeAdapterFactory.java:216)
at retrofit2.converter.gson.GsonResponseBodyConverter.convert(GsonResponseBodyConverter.java:37)
at retrofit2.converter.gson.GsonResponseBodyConverter.convert(GsonResponseBodyConverter.java:25)
at retrofit2.ServiceMethod.toResponse(ServiceMethod.java:116)
at retrofit2.OkHttpCall.parseResponse(OkHttpCall.java:211)
at retrofit2.OkHttpCall.execute(OkHttpCall.java:174)
at retrofit2.adapter.rxjava.RxJavaCallAdapterFactory$CallOnSubscribe.call(RxJavaCallAdapterFactory.java:144)
at retrofit2.adapter.rxjava.RxJavaCallAdapterFactory$CallOnSubscribe.call(RxJavaCallAdapterFactory.java:125)
at rx.Observable$2.call(Observable.java:162)
at rx.Observable$2.call(Observable.java:154)
at rx.Observable$2.call(Observable.java:162)
at rx.Observable$2.call(Observable.java:154)
at rx.Observable.unsafeSubscribe(Observable.java:8314)
at rx.internal.operators.OperatorSubscribeOn$1.call(OperatorSubscribeOn.java:94)
at rx.internal.schedulers.ScheduledAction.run(ScheduledAction.java:55)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:423)
at java.util.concurrent.FutureTask.run(FutureTask.java:237)
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:269)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1113)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:588)
at java.lang.Thread.run(Thread.java:818)
public class UriAdpter extends TypeAdapter<Uri> {
@Override
public void write(JsonWriter out, Uri value) throws IOException {
out.value(value.toString());
}
@Override
public Uri read(JsonReader in) throws IOException {
if (in.peek() == JsonToken.NULL) {
in.nextNull();
return null;
}
return Uri.parse(in.nextString());
}
}