Hibernate | Why is the transaction “half-committed

问题:

I'm working with Hibernate in a Spring Boot project.

I have the following piece of code:

public class SomeService {

    private Dependency dependency;

    @Transactional(readOnly=false)
    public void doSomething() {
        //some BL code...

        dependency.doSomeDbManipualation();

        someOperation();
    }

    public void someOperation() {
        //some code that eventually fails
    }
}

public class Dependency {

    public void doSomeDbManipulation() {
        Entity entity = ...; //get the entity from current session by its key
        if (entity != null) {
            session.delete(entity);
        }

        OtherEntity oEntity = new OtherEntity();
        //set its fields
        Long oEntityId = session.save(oEntity);

        entity = new Entity();
        entity.setForeignKey(oEntityId);
        //set other fields
        session.persist(entity);
    }
}

Now, I have in the database an entity with the relevant key. So I expect that when calling the service, the code that looks for the entity will indeed find it. But since someOperation() fails, I expect to see no change in the DB.

In fact, after calling someService.doSomething() (and failing), I look in the DB and I see that the existing entity was deleted! But a new entity was not created (which is ok).

Why is this transaction "half committed"?

EDIT: Apparently delete() and save() are committed immediately. When I debug, I see that entity is immediately deleted after this line in code is done. Also OtherEntity is added immediately to the DB. persist() is not committed immediately.

I use AspectJ for transaction management. Here is the relevant part from my pom.xml:

<project>
    ...
    <dependencies>
        ...
        <dependency>
            <groupId>org.aspectj</groupId>
            <artifactId>aspectjrt</artifactId>
        </dependency>

        <dependency>
            <groupId>org.aspectj</groupId>
            <artifactId>aspectjweaver</artifactId>
        </dependency>
        ...
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>

            <plugin>
                <groupId>org.codehaus.mojo</groupId>
                <artifactId>aspectj-maven-plugin</artifactId>
                <version>1.7</version>
                <dependencies>
                    <dependency>
                        <groupId>org.aspectj</groupId>
                        <artifactId>aspectjtools</artifactId>
                        <version>1.8.3</version>
                    </dependency>
                </dependencies>
                <configuration>
                    <showWeaveInfo>true</showWeaveInfo>
                    <outxml>true</outxml>
                    <forceAjcCompile>true</forceAjcCompile>
                    <source>1.8</source>
                    <target>1.8</target>
                    <Xlint>ignore</Xlint>
                    <complianceLevel>1.8</complianceLevel>
                    <encoding>UTF-8</encoding>
                    <verbose>true</verbose>
                    <preserveAllLocals>true</preserveAllLocals>
                    <aspectLibraries>
                        <aspectLibrary>
                            <groupId>org.springframework</groupId>
                            <artifactId>spring-aspects</artifactId>
                        </aspectLibrary>
                    </aspectLibraries>
                </configuration>
                <executions>
                    <execution>
                        <id>AspectJ-Compile</id>
                        <phase>process-classes</phase>
                        <goals>
                            <goal>compile</goal>
                        </goals>
                    </execution>
                </executions>
            </plugin>
        </plugins>
        ...
    </build>
</project>

回答1:

I don't know why aspect j is explicitly added as dependency in pom file.if u r using spring boot u will get aspects out of the box.I have seen unpredictable behavior when duplicate jars are present in the classpath.

Also I failed to understand why the DB manipulation method is called from a method which itself is marked for read-only transaction.

I feel design is not correct here.

回答2:

I found the solution to the issue. I had multiple @ComponentScan annotations, in several classes. When I removed them all, and left just one, all was working as expected.

I don't understand the reason to this strange behavior, so I posted a separate question about this, here