使用AspectJ，Neo4j NodeEntities和事务时，我遇到了一个奇怪的问题。
我正在开发一个spring应用程序并使用spring-data-neo4j和aspectj编织。问题是，我获取的实体在事务之外是空的。没有AspectJ，一切都按预期工作。
以下是maven的完整测试用例：
的pom.xml
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>org.test</groupId>
<artifactId>demo</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>jar</packaging>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.2.4.RELEASE</version>
</parent>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<java.version>1.8</java.version>
<neo4j.version>2.1.7</neo4j.version>
<spring-data-commons.version>1.10.0.RELEASE</spring-data-commons.version>
<spring-data-neo4j.version>3.3.0.RELEASE</spring-data-neo4j.version>
</properties>
<dependencies>
<!-- spring dependencies -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-aop</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-tx</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.data</groupId>
<artifactId>spring-data-commons</artifactId>
<version>${spring-data-commons.version}</version>
</dependency>
<!-- spring + neo4j dependencies -->
<dependency>
<groupId>org.springframework.data</groupId>
<artifactId>spring-data-neo4j</artifactId>
<version>${spring-data-neo4j.version}</version>
</dependency>
<dependency>
<groupId>org.springframework.data</groupId>
<artifactId>spring-data-neo4j-tx</artifactId>
<version>${spring-data-neo4j.version}</version>
</dependency>
<dependency>
<groupId>org.springframework.data</groupId>
<artifactId>spring-data-neo4j-aspects</artifactId>
<version>${spring-data-neo4j.version}</version>
</dependency>
<!-- for aspectj -->
<dependency>
<groupId>org.aspectj</groupId>
<artifactId>aspectjrt</artifactId>
</dependency>
<dependency>
<groupId>javax.persistence</groupId>
<artifactId>persistence-api</artifactId>
<version>1.0</version>
<optional>true</optional>
<scope>provided</scope>
</dependency>
<!-- for testing -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.neo4j</groupId>
<artifactId>neo4j-kernel</artifactId>
<version>${neo4j.version}</version>
<type>test-jar</type>
<scope>test</scope>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
<profiles>
<profile>
<id>aspects</id>
<build>
<plugins>
<!-- disable default compiler -->
<plugin>
<artifactId>maven-compiler-plugin</artifactId>
<executions>
<execution>
<id>default-compile</id>
<phase>none</phase>
</execution>
</executions>
</plugin>
<!-- enable aspectj compiler -->
<plugin>
<groupId>org.codehaus.mojo</groupId>
<artifactId>aspectj-maven-plugin</artifactId>
<version>1.7</version>
<dependencies>
<dependency>
<groupId>org.aspectj</groupId>
<artifactId>aspectjrt</artifactId>
<version>1.8.5</version>
</dependency>
<dependency>
<groupId>org.aspectj</groupId>
<artifactId>aspectjtools</artifactId>
<version>1.8.5</version>
</dependency>
</dependencies>
<executions>
<execution>
<goals>
<goal>compile</goal>
<goal>test-compile</goal>
</goals>
</execution>
</executions>
<configuration>
<outxml>true</outxml>
<aspectLibraries>
<aspectLibrary>
<groupId>org.springframework</groupId>
<artifactId>spring-aspects</artifactId>
</aspectLibrary>
<aspectLibrary>
<groupId>org.springframework.data</groupId>
<artifactId>spring-data-neo4j-aspects</artifactId>
</aspectLibrary>
</aspectLibraries>
<complianceLevel>${java.version}</complianceLevel>
<source>${java.version}</source>
<target>${java.version}</target>
</configuration>
</plugin>
</plugins>
</build>
</profile>
</profiles>
<repositories>
<repository>
<id>spring-libs-milestone</id>
<name>Spring Milestone</name>
<url>https://repo.spring.io/libs-milestone</url>
</repository>
</repositories>
</project>
演示/ DemoNode.java
package demo;
import org.springframework.data.neo4j.annotation.GraphId;
import org.springframework.data.neo4j.annotation.Indexed;
import org.springframework.data.neo4j.annotation.NodeEntity;
@NodeEntity
public class DemoNode {
@GraphId
private Long id;
@Indexed(unique = true)
private String name;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
}
演示/ DemoRepository.java
package demo;
import org.springframework.data.neo4j.repository.GraphRepository;
public interface DemoRepository extends GraphRepository<DemoNode> {
public DemoNode findByName(String name);
}
演示/ DemoApplicationTests.java
package demo;
import static org.junit.Assert.assertEquals;
import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.neo4j.graphdb.GraphDatabaseService;
import org.neo4j.graphdb.Transaction;
import org.neo4j.test.TestGraphDatabaseFactory;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.support.AnnotationConfigContextLoader;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.neo4j.aspects.config.Neo4jAspectConfiguration;
import org.springframework.data.neo4j.config.EnableNeo4jRepositories;
import org.springframework.data.neo4j.support.node.Neo4jHelper;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
import org.springframework.transaction.annotation.EnableTransactionManagement;
@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(loader = AnnotationConfigContextLoader.class)
public class DemoApplicationTests {
@Configuration
@ComponentScan("demo")
@EnableTransactionManagement
@EnableNeo4jRepositories(basePackages = "demo")
public static class DemoConfiguration extends Neo4jAspectConfiguration {
public DemoConfiguration() {
setBasePackage("demo");
}
@Bean(destroyMethod = "shutdown")
public GraphDatabaseService graphDatabaseService() {
return new TestGraphDatabaseFactory().newImpermanentDatabase();
}
}
@Autowired
private GraphDatabaseService graphDbService;
@Autowired
private DemoRepository demoRepo;
@Before
public void resetDb() {
Neo4jHelper.cleanDb(graphDbService);
}
// NOT successful
@Test
public void testNeo4jTransaction() {
DemoNode node;
final String name = "demo";
try (Transaction tx = graphDbService.beginTx()) {
node = new DemoNode();
node.setName(name);
node = demoRepo.save(node);
tx.success();
}
assertEquals(name, node.getName());
try (Transaction tx = graphDbService.beginTx()) {
node = demoRepo.findByName(name);
tx.success();
}
assertEquals(name, node.getName()); // expected:<demo> but was:<null>
}
// successful
@Test
public void testNeo4jWithGetTransaction() {
DemoNode node;
final String name = "demo";
try (Transaction tx = graphDbService.beginTx()) {
node = new DemoNode();
node.setName(name);
node = demoRepo.save(node);
tx.success();
}
assertEquals(name, node.getName());
try (Transaction tx = graphDbService.beginTx()) {
node = demoRepo.findByName(name);
tx.success();
}
try (Transaction tx = graphDbService.beginTx()) {
assertEquals(name, node.getName());
}
}
}
使用mvn test测试时，一切都很好。但是当使用aspectj（mvn test -Paspects）时，它将失败：
DemoApplicationTests.testNeo4jNativeTransaction:64 expected:<demo> but was:<null>
我在调试时发现：在使用AspectJ的事务中，我可以使用getter检索名称。但是：所有属性始终为null。所以我的猜测是：AspectJ weaving将值存储在其他地方并覆盖setter / getter。新的getter需要一个活动的事务，因此在事务之外它将不起作用/将使用不与null属性一起使用的默认getter。
当我提高调试级别时，我可以看到一些关于此的消息：
DEBUG o.s.d.n.f.DetachedEntityState - Outside of transaction, GET value from field class java.lang.String name rel: false idx: true
我做错了吗？我需要创建一个克隆并返回吗？ Imho这将是一个丑陋的方式......
提前致谢！我已经搜索并尝试了几个小时，但无法在stackoverflow或互联网上的其他地方找到任何解决方案和任何其他问题。也许这是一个错误......也许是预期的行为，或者我做错了......我不知道。
更新
我添加了第二个有效的测试。它有一个围绕getter的事务。因此，当在事务中调用getter时，一切都很好。但我认为这是一种奇怪的行为。在交易之外，实体应该分离，但可以使用。