From 8bdc6673b6d4d4435827e4bb40dafbe67a78f88e Mon Sep 17 00:00:00 2001 From: Markus KARG Date: Thu, 19 Sep 2019 13:25:34 +0000 Subject: [PATCH] Fixed [JOHNZON-277] Fails to deserialize inner empty JSON block {} at OBJECT_START Signed-off-by: Markus KARG --- .../JohnzonDeserializationContext.java | 2 + .../DeserializationContextTest.java | 83 +++++++++++++++++++ 2 files changed, 85 insertions(+) create mode 100644 johnzon-jsonb/src/test/java/org/apache/johnzon/jsonb/serializer/DeserializationContextTest.java diff --git a/johnzon-jsonb/src/main/java/org/apache/johnzon/jsonb/serializer/JohnzonDeserializationContext.java b/johnzon-jsonb/src/main/java/org/apache/johnzon/jsonb/serializer/JohnzonDeserializationContext.java index a3b58dda..b8f55c42 100644 --- a/johnzon-jsonb/src/main/java/org/apache/johnzon/jsonb/serializer/JohnzonDeserializationContext.java +++ b/johnzon-jsonb/src/main/java/org/apache/johnzon/jsonb/serializer/JohnzonDeserializationContext.java @@ -63,6 +63,8 @@ private JsonValue read(final JsonParser parser) { parseObject(null, parser, objectBuilder); return objectBuilder.build(); } + case END_OBJECT: + return JsonValue.EMPTY_JSON_OBJECT; case START_ARRAY: final JsonArrayBuilder arrayBuilder = builderFactory.createArrayBuilder(); parseArray(parser, arrayBuilder); diff --git a/johnzon-jsonb/src/test/java/org/apache/johnzon/jsonb/serializer/DeserializationContextTest.java b/johnzon-jsonb/src/test/java/org/apache/johnzon/jsonb/serializer/DeserializationContextTest.java new file mode 100644 index 00000000..f0c366e0 --- /dev/null +++ b/johnzon-jsonb/src/test/java/org/apache/johnzon/jsonb/serializer/DeserializationContextTest.java @@ -0,0 +1,83 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. The ASF licenses this file + * to you under the Apache License, Version 2.0 (the + * "License"); you may not use this file except in compliance + * with the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, + * software distributed under the License is distributed on an + * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY + * KIND, either express or implied. See the License for the + * specific language governing permissions and limitations + * under the License. + */ +package org.apache.johnzon.jsonb.serializer; + +import static org.junit.Assert.assertNotNull; + +import java.lang.reflect.Type; + +import javax.json.bind.Jsonb; +import javax.json.bind.JsonbBuilder; +import javax.json.bind.JsonbConfig; +import javax.json.bind.serializer.DeserializationContext; +import javax.json.bind.serializer.JsonbDeserializer; +import javax.json.stream.JsonParser; + +import org.junit.Test; + +/** + * Tests compliance of {@link JohnzonDeserializationContext} with {@link DeserializationContext} wrt. empty inner JSON blocks. + * + * According to https://github.com/eclipse-ee4j/jsonb-api/blob/master/api/src/main/java/javax/json/bind/serializer/DeserializationContext.java#L34-L35 a + * deserialization context must be able to deserialize an object EVEN IN CASE the parser cursor is at {@code START_OBJECT}. + * + * Quote: "JsonParser cursor have to be at KEY_NAME before START_OBJECT / START_ARRAY, or at START_OBJECT / START_ARRAY 35 * to call this method." + * + * The latter case, "...or at START_OBJECT..." seems to fail in case the inner JSON to parse is an empty block "{}". + */ +public class DeserializationContextTest { + + @Test + public void deserializeClass() throws Exception { + try (final Jsonb jsonb = JsonbBuilder.create()) { + // CAN create Bar instance from empty JSON inside of Foo => Parsing empty blocks seems to be allowed. + final Foo fooWithBar = jsonb.fromJson("{\"bar\":{}}", Foo.class); + assertNotNull(fooWithBar); + assertNotNull(fooWithBar.bar); + } + + try (final Jsonb jsonb = JsonbBuilder.create(new JsonbConfig().withDeserializers(new CustomDeserializer()))) { + // CANNOT create Bar instance from empty JSON when parser cursor is at START_OBJECT => Bug in Johnzon + final Foo fooWithBar = jsonb.fromJson("{\"bar\":{}}", Foo.class); // throws exception "Unknown structure: END_OBJECT" + assertNotNull(fooWithBar); + assertNotNull(fooWithBar.bar); + } + } + + public static class CustomDeserializer implements JsonbDeserializer { + @Override + public Foo deserialize(final JsonParser parser, final DeserializationContext ctx, final Type rtType) { + parser.next(); // now cursor is at START_OBJECT of outer Foo, so let's create empty Foo... + final Foo foo = new Foo(); + parser.next(); // now cursor is at KEY_NAME "bar" + parser.next(); // now cursor is at START_OBJECT of inner Bar, so let's fill Foo.bar... + foo.bar = ctx.deserialize(Bar.class, parser); + return foo; + } + } + + public static class Foo { + public Bar bar; + } + + public static class Bar { + // intentionally left blank + } + +}