ValueObject deserialization exception

[floresek]

Hi,

Suppose two classes:

class Master {
    @Id
    String id;
    Detail detail;

    public Master(String id) {
        this.id = id;
    }

}

@ValueObject
class Detail {
    String data;

    public Detail(String data) {
        this.data = data;
    }
}

If I provide Detail object before initil commit, everything is OK:

        Master master = new Master("1");
        master.detail = new Detail("details");
        javers.commit("anonymous", master);

If I provide Detail object before after initial commit, everything is OK:

        Master master = new Master("1");
        javers.commit("anonymous", master);
        master.detail = new Detail("details");
        javers.commit("anonymous", master);
        List<Change> changes = javers
                .findChanges(QueryBuilder.byInstanceId("1", Master.class)
                        .withNewObjectChanges(true)
                        .build());

I got deserialization error during findChanges operation (or third commit attempt):

java.lang.NullPointerException
    at org.javers.core.json.typeadapter.commit.GlobalIdTypeAdapter.parseClass(GlobalIdTypeAdapter.java:117)
    at org.javers.core.json.typeadapter.commit.GlobalIdTypeAdapter.parseUnboundedValueObject(GlobalIdTypeAdapter.java:51)
    at org.javers.core.json.typeadapter.commit.GlobalIdTypeAdapter.fromJson(GlobalIdTypeAdapter.java:46)
    at org.javers.core.json.typeadapter.commit.GlobalIdTypeAdapter.fromJson(GlobalIdTypeAdapter.java:18)
    at org.javers.core.json.JsonConverterBuilder$2.deserialize(JsonConverterBuilder.java:144)
    at com.google.gson.TreeTypeAdapter.read(TreeTypeAdapter.java:58)
    at com.google.gson.Gson.fromJson(Gson.java:810)
    at com.google.gson.Gson.fromJson(Gson.java:875)
    at com.google.gson.Gson$1.deserialize(Gson.java:128)
    at org.javers.core.json.typeadapter.commit.GlobalIdTypeAdapter.parseValueObjectId(GlobalIdTypeAdapter.java:58)
    at org.javers.core.json.typeadapter.commit.GlobalIdTypeAdapter.fromJson(GlobalIdTypeAdapter.java:44)
    at org.javers.core.json.typeadapter.commit.GlobalIdTypeAdapter.fromJson(GlobalIdTypeAdapter.java:18)
    at org.javers.core.json.JsonConverterBuilder$2.deserialize(JsonConverterBuilder.java:144)
    at com.google.gson.TreeTypeAdapter.read(TreeTypeAdapter.java:58)
    at com.google.gson.Gson.fromJson(Gson.java:810)
    at com.google.gson.Gson.fromJson(Gson.java:875)
    at org.javers.core.json.JsonConverter.fromJson(JsonConverter.java:85)
    at org.javers.core.json.JsonConverter$1.deserialize(JsonConverter.java:60)
    at org.javers.core.json.typeadapter.commit.CdoSnapshotStateDeserializer.decodePropertyValue(CdoSnapshotStateDeserializer.java:48)
    at org.javers.core.json.typeadapter.commit.CdoSnapshotStateDeserializer.deserialize(CdoSnapshotStateDeserializer.java:39)
    at org.javers.core.json.JsonConverter.snapshotStateFromJson(JsonConverter.java:107)
    at org.javers.repository.sql.finders.CdoSnapshotObjectMapper.createObject(CdoSnapshotObjectMapper.java:45)
    at org.javers.repository.sql.finders.CdoSnapshotObjectMapper.createObject(CdoSnapshotObjectMapper.java:24)
    at org.polyjdbc.core.query.TransactionalQueryRunner.queryCollection(TransactionalQueryRunner.java:88)
    at org.polyjdbc.core.query.TransactionalQueryRunner.queryList(TransactionalQueryRunner.java:76)
    at org.javers.repository.sql.finders.CdoSnapshotFinder.queryForCdoSnapshots(CdoSnapshotFinder.java:97)
    at org.javers.repository.sql.finders.CdoSnapshotFinder.getStateHistory(CdoSnapshotFinder.java:74)
    at org.javers.repository.sql.JaversSqlRepository.getStateHistory(JaversSqlRepository.java:76)
    at org.javers.repository.api.JaversExtendedRepository.getStateHistory(JaversExtendedRepository.java:76)
    at org.javers.repository.api.JaversExtendedRepository.getChangeHistory(JaversExtendedRepository.java:55)
    at org.javers.repository.jql.QueryRunner.queryForChanges(QueryRunner.java:74)
    at org.javers.core.JaversCore.findChanges(JaversCore.java:114)
    at javers.JaversTest.createTestMaster(JaversTest.java:111)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)
    at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
    at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
    at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
    at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:26)
    at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:78)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:57)
    at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
    at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
    at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
    at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
    at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
    at org.junit.runner.JUnitCore.run(JUnitCore.java:137)
    at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:78)
    at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:212)
    at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:68)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at com.intellij.rt.execution.application.AppMain.main(AppMain.java:140)

In first (working) scenario master is serialized as:

{
  "id": "1",
  "detail": {
    "valueObject": "javers.Detail",
    "ownerId": {
      "entity": "javers.Master",
      "cdoId": "1"
    },
    "fragment": "detail"
  }
}

In second scenario master is serialized as:

{
  "id": "1",
  "detail": {
    "valueObject": "javers.Detail",
    "ownerId": {
      "instance": {
        "entity": "javers.Master",
        "cdoId": "1"
      },
      "primaryKey": {
        "reference": 4100
      }
    },
    "fragment": "detail"
  }
}

Could you fix this bug, please?

Cheers
Mariusz

[bartoszwalacik]

Thanks for reporting, will check it

[bartoszwalacik]

ok, I can reproduce it on H2 repository

[floresek]

I hope you deal with it quickly ;)

[floresek]

The problem (with deserialization) occurs also when updating entity with previously (initially) set reference ValueObjects.

class Master {
    @Id
    String id;
    Detail detail;
    String data;

    List<Detail> list = new ArrayList<>();
    Set<Detail> set = new HashSet<>();
    Map<String, Detail> map = new HashMap<>();
    Detail[] array;

    public Master(String id) {
        this.id = id;
    }
}

@ValueObject
class Detail {
    String data;

    public Detail(String data) {
        this.data = data;
    }
}

        ...
        Master master = new Master("2");
        master.data = "data";
        master.detail = new Detail("details");
        javers.commit("anonymous", master);
        master.data = "data2";
        javers.commit("anonymous", master);
        List<Change> changes = javers
                .findChanges(QueryBuilder.byInstanceId("2", Master.class)
                        .withNewObjectChanges(true)
                        .build());
        String changeLog = javers.processChangeList(changes, getChangeLogger());
        ...

During second commit the structure of previously saved json is changed from ownerId:entity to ownerId:instance/primaryKey and while deserialization exception occurs.

Similar problem (with deserialization) occurs when using list/set/map/array of ValueObjects.

[bartoszwalacik]

bugs have high priority, expect a fix after weekend

[floresek]

thanks ;)

[floresek]

Przepraszam, że Cię nękam issues'ami, ale spodobał mi się javers i chciałem go nieco zewaluować ;)

[bartoszwalacik]

Miło, teraz jestem na wypadzie w Beskid Sądecki wiec ten bug musi poczekac do poniedzialku. Btw w javersie jest duże zapotrzebowanie na kontrybucje...

[floresek]

OK, jak się wystarczająco wgryzę ;)

[bartoszwalacik]

Found a bug in serializing ValueObject references in sql repository. In some cases JSON is malformed

[bartoszwalacik]

fixed in v 1.3.10

[floresek]

Excellent, thanks ;)