Gson serialization from JsonSerializationContext triggers an exception if a typeadapter uses jsonValue #1289
Description
Hi,
I'm having trouble combining a JsonSerializer with a TypeAdapter that uses JsonWriter ::jsonValue
Here is the TypeAdapter for BigDecimals that I created:
public class BigDecimalTypeAdapter extends TypeAdapter<BigDecimal> {
public static final BigDecimalTypeAdapter INSTANCE = new BigDecimalTypeAdapter();
@Override
public void write(JsonWriter out, BigDecimal value) throws IOException {
if (value == null) {
out.nullValue();
} else {
out.jsonValue(value.stripTrailingZeros().toPlainString());
}
}
@Override
public BigDecimal read(JsonReader in) throws IOException {
return TypeAdapters.BIG_DECIMAL.read(in);
}
}And that is a generic serializer for one of my interfaces:
public class MyInterfaceJsonSerializer implements JsonSerializer<IMyInterface> {
@Override
public JsonElement serialize(IMyInterface src, Type typeOfSrc, JsonSerializationContext context) {
Map<String, Object> map = new TreeMap<>();
Map<String, Object> map = new TreeMap<>();
Map<String, Object> failed = new TreeMap<>();
Method[] methods = IMyInterface.class.getMethods();
for (int i = 0; i < methods.length; i++) {
Method method = methods[i];
String key = makePropertyName(method.getName());
try {
Object result = method.invoke(src);
map.put(key, result);
} catch (Exception e) {
failed.put(key, e.getMessage());
}
}
if (!failed.isEmpty())
map.put("__failed", failed);
return context.serialize(map); // Here that will call the BigDecimalTypeAdapter if any value is BigDecimal
}
}When I try to serialize an instance of IMyInterface
java.lang.AssertionError
at com.google.gson.internal.bind.JsonTreeWriter$1.write(JsonTreeWriter.java:36)
at java.io.Writer.write(Writer.java:192)
at java.io.Writer.write(Writer.java:157)
at java.io.Writer.append(Writer.java:227)
at com.google.gson.stream.JsonWriter.jsonValue(JsonWriter.java:436)
at my.common.gson.BigDecimalTypeAdapter.write(BigDecimalTypeAdapter.java:22)
at my.common.gson.BigDecimalTypeAdapter.write(BigDecimalTypeAdapter.java:1)
at com.google.gson.internal.bind.TypeAdapterRuntimeTypeWrapper.write(TypeAdapterRuntimeTypeWrapper.java:69)
at com.google.gson.internal.bind.MapTypeAdapterFactory$Adapter.write(MapTypeAdapterFactory.java:208)
at com.google.gson.internal.bind.MapTypeAdapterFactory$Adapter.write(MapTypeAdapterFactory.java:145)
at com.google.gson.Gson.toJson(Gson.java:669)
at com.google.gson.Gson.toJsonTree(Gson.java:562)
at com.google.gson.Gson.toJsonTree(Gson.java:541)
at com.google.gson.internal.bind.TreeTypeAdapter$GsonContextImpl.serialize(TreeTypeAdapter.java:155)
at my.service.ib.MyInterfaceJsonSerializer.serialize(MyInterfaceJsonSerializer.java:37)
at my.service.ib.MyInterfaceJsonSerializer.serialize(MyInterfaceJsonSerializer.java:1)
at com.google.gson.internal.bind.TreeTypeAdapter.write(TreeTypeAdapter.java:81)
at com.google.gson.Gson.toJson(Gson.java:669)
at com.google.gson.Gson.toJson(Gson.java:648)
at com.google.gson.Gson.toJson(Gson.java:603)
at com.google.gson.Gson.toJson(Gson.java:583)
at my.service.ib.MyHandlerTest.test_gson(MyHandlerTest.java:26)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:47)
at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:44)
at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:271)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:70)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:50)
at org.junit.runners.ParentRunner$3.run(ParentRunner.java:238)
at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:63)
at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:236)
at org.junit.runners.ParentRunner.access$000(ParentRunner.java:53)
at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:229)
at org.junit.runners.ParentRunner.run(ParentRunner.java:309)
at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:86)
at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:538)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:760)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:460)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:206)
This error comes from JsonTreeWriter.UNWRITABLE_WRITER::write.
I'm not sure if i'm doing something wrong here. If I change jsonValue to value it works nice except that I get double quotes around my BigDecimal values which i'd like to avoid.
Here is how i create my Gson object:
public static final Gson GSON = new GsonBuilder()
.registerTypeHierarchyAdapter(IMyInterface.class, new MyInterfaceJsonSerializer())
.registerTypeAdapter(BigDecimal.class, BigDecimalTypeAdapter.INSTANCE)
.create();Am I missing something here ?