Hibernate Rest状态码：200但实体未保存。

Question

我正在尝试使用Hibernate和Jersey保存一个实体。

我尝试发送的JSON是：

{
"firstname":"Jon",
"middlename":"J",
"lastname":"Smith",
"dob":"10-10-1990",
"gender":"male"
}

当我使用Postman发送请求时，返回Status: 200 OK，但记录未保存到数据库中。

我使用的数据库是Neo4j。

这是我的PersonDAO类：

package com.Neo4jRestAPI;

import java.util.List;

import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.persistence.EntityTransaction;
import javax.persistence.Persistence;

import org.hibernate.HibernateException;

import com.google.gson.Gson;

public class PersonDAO {

    public void addPerson(Person person){

        try {
            EntityManagerFactory emf = Persistence.createEntityManagerFactory("persistence");
            EntityManager em = emf.createEntityManager();
            EntityTransaction tx = em.getTransaction();
            tx.begin();

            Person p = new Person();

            p.setFirstname(person.getFirstname());
            p.setMiddlename(person.getMiddlename());
            p.setLastname(person.getLastname());
            p.setDob(person.getDob());
            p.setGender(person.getGender());

            em.persist(p);
            em.flush();     
            tx.commit();
            em.clear(); 
            em.close(); 
            emf.close();
            }
        catch ( Exception e ) {
            e.printStackTrace();
        }
    }
}

这是我尝试发送数据的方法：

@POST
@Path("/person")
@Consumes("application/json")
public Response addPerson(Person person){

     person.setFirstname(person.getFirstname());
     person.setMiddlename(person.getMiddlename());
     person.setLastname(person.getLastname());
     person.setDob(person.getDob());
     person.setGender(person.getGender());

     PersonDAO dao = new PersonDAO();

     dao.addPerson(person);

     return Response.ok().build();
}

有没有人知道我在这里做错了什么？

编辑

我可以使用 native query 保存实体，但这种方式不会自动生成id。 我仍然无法按照上述方法保存实体

当我删除@GeneratedValue并在JSON中指定id 时，我就能够保存实体，因此我认为问题出在那里。 我尝试过几种策略，但都没有起作用。

这是我尝试自动生成id 的方式：

@Entity
@Table(name="Person")
public class Person {

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    @Column(name = "id")
    private Long id;

此外，当我打印方法getId()时，会得到自增的值。

以下是已执行的Cypher查询：

"{"statements":[{"statement":"CREATE (n:ENTITY:Person {props}) RETURN n","parameters":{"props":{"firstname":"Jon","gender":"male","dob":"10-10-1990","middlename":"J","id":99,"lastname":"Smith"}},"includeStats":false,"resultDataContents":["graph"]}]}"

我也遇到了事务回滚错误，但是它没有说明为什么被回滚：

"Neo.ClientError.Transaction.TransactionNotFound","message":"Unrecognized transaction id. Transaction may have timed out and been rolled back

这是我的persistence.xml文件。

<?xml version="1.0"?>
<persistence xmlns="http://java.sun.com/xml/ns/persistence"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd"
         version="2.0">

<persistence-unit name="persistence">
    <provider>org.hibernate.ogm.jpa.HibernateOgmPersistence</provider>
    <properties>
        <property name="hibernate.ogm.datastore.provider" value="neo4j_http"/>
        <property name="hibernate.ogm.neo4j.database_path" value="C://path//to//database"/>
        <property name="hibernate.ogm.datastore.host" value="localhost:7474"/>
        <property name="hibernate.ogm.datastore.username" value="neo4j"/>
        <property name="hibernate.ogm.datastore.password" value="root"/>
    </properties>
  </persistence-unit>
  </persistence>

编辑

这是我得到的堆栈跟踪：

log4j:WARN No appenders could be found for logger (org.jboss.logging).
log4j:WARN Please initialize the log4j system properly.
log4j:WARN See http://logging.apache.org/log4j/1.2/faq.html#noconfig for more info. 

当我使用log4j并添加BasicConfigurator.configure()时，我会得到以下错误信息（由于日志太长，无法在此贴出完整内容，所以我只贴出了抛出错误的部分）:

2342 [http-nio-8080-exec-4] DEBUG org.apache.http.wire  -  >> "{"statements":[{"statement":"CREATE (n:ENTITY:Person {props}) RETURN n","parameters":{"props":{"firstname":"Anna","gender":"female","dob":"10-10-1990","middlename":"J","id":57,"lastname":"Smith"}},"includeStats":false,"resultDataContents":["graph"]}]}"
2345 [http-nio-8080-exec-4] DEBUG org.apache.http.wire  -  << "HTTP/1.1 200 OK[\r][\n]"
2345 [http-nio-8080-exec-4] DEBUG org.apache.http.wire  -  << "Date: Tue, 03 Oct 2017 09:01:10 GMT[\r][\n]"
2345 [http-nio-8080-exec-4] DEBUG org.apache.http.wire  -  << "Content-Type: application/json[\r][\n]"
2345 [http-nio-8080-exec-4] DEBUG org.apache.http.wire  -  << "Access-Control-Allow-Origin: *[\r][\n]"
2345 [http-nio-8080-exec-4] DEBUG org.apache.http.wire  -  << "Content-Length: 372[\r][\n]"
2345 [http-nio-8080-exec-4] DEBUG org.apache.http.wire  -  << "Server: Jetty(9.2.z-SNAPSHOT)[\r][\n]"
2345 [http-nio-8080-exec-4] DEBUG org.apache.http.wire  -  << "[\r][\n]"
2345 [http-nio-8080-exec-4] DEBUG org.apache.http.impl.conn.DefaultClientConnection  - Receiving response: HTTP/1.1 200 OK
2345 [http-nio-8080-exec-4] DEBUG org.apache.http.headers  - << HTTP/1.1 200 OK
2345 [http-nio-8080-exec-4] DEBUG org.apache.http.headers  - << Date: Tue, 03 Oct 2017 09:01:10 GMT
2345 [http-nio-8080-exec-4] DEBUG org.apache.http.headers  - << Content-Type: application/json
2345 [http-nio-8080-exec-4] DEBUG org.apache.http.headers  - << Access-Control-Allow-Origin: *
2345 [http-nio-8080-exec-4] DEBUG org.apache.http.headers  - << Content-Length: 372
2345 [http-nio-8080-exec-4] DEBUG org.apache.http.headers  - << Server: Jetty(9.2.z-SNAPSHOT)
2345 [http-nio-8080-exec-4] DEBUG org.apache.http.impl.client.DefaultHttpClient  - Connection can be kept alive indefinitely
2346 [http-nio-8080-exec-4] DEBUG org.apache.http.wire  -  << "{"commit":"http://localhost:7474/db/data/transaction/53/commit","results":[{"columns":["n"],"data":[{"graph":{"nodes":[{"id":"10","labels":["ENTITY","Person"],"properties":{"firstname":"Anna","gender":"female","dob":"10-10-1990","middlename":"J","id":57,"lastname":"Smith"}}],"relationships":[]}}]}],"transaction":{"expires":"Tue, 03 Oct 2017 09:02:10 +0000"},"errors":[]}"
2346 [http-nio-8080-exec-4] DEBUG org.apache.http.impl.conn.PoolingClientConnectionManager  - Connection [id: 1][route: {}->http://localhost:7474] can be kept alive indefinitely
2346 [http-nio-8080-exec-4] DEBUG org.apache.http.impl.conn.PoolingClientConnectionManager  - Connection released: [id: 1][route: {}->http://localhost:7474][total kept alive: 1; route allocated: 2 of 10; total allocated: 2 of 10]
2350 [http-nio-8080-exec-4] DEBUG org.hibernate.engine.transaction.internal.TransactionImpl  - committing
2350 [http-nio-8080-exec-4] DEBUG org.hibernate.event.internal.AbstractFlushingEventListener  - Processing flush-time cascades
2350 [http-nio-8080-exec-4] DEBUG org.hibernate.event.internal.AbstractFlushingEventListener  - Dirty checking collections
2350 [http-nio-8080-exec-4] DEBUG org.hibernate.event.internal.AbstractFlushingEventListener  - Flushed: 0 insertions, 0 updates, 0 deletions to 1 objects
2350 [http-nio-8080-exec-4] DEBUG org.hibernate.event.internal.AbstractFlushingEventListener  - Flushed: 0 (re)creations, 0 updates, 0 removals to 0 collections
2350 [http-nio-8080-exec-4] DEBUG org.hibernate.internal.util.EntityPrinter  - Listing entities:
2350 [http-nio-8080-exec-4] DEBUG org.hibernate.internal.util.EntityPrinter  - com.Neo4jRestAPI.Person{firstname=Anna, gender=female, relationship_type=null, dob=10-10-1990, middlename=J, id=57, relationship=null, lastname=Smith}
2350 [http-nio-8080-exec-4] DEBUG org.apache.http.impl.conn.PoolingClientConnectionManager  - Connection request: [route: {}->http://localhost:7474][total kept alive: 1; route allocated: 2 of 10; total allocated: 2 of 10]
2350 [http-nio-8080-exec-4] DEBUG org.apache.http.impl.conn.PoolingClientConnectionManager  - Connection leased: [id: 1][route: {}->http://localhost:7474][total kept alive: 0; route allocated: 2 of 10; total allocated: 2 of 10]
2350 [http-nio-8080-exec-4] DEBUG org.apache.http.impl.client.DefaultHttpClient  - Stale connection check
2352 [http-nio-8080-exec-4] DEBUG org.apache.http.client.protocol.RequestAddCookies  - CookieSpec selected: best-match
2352 [http-nio-8080-exec-4] DEBUG org.apache.http.client.protocol.RequestAuthCache  - Auth cache not set in the context
2352 [http-nio-8080-exec-4] DEBUG org.apache.http.client.protocol.RequestProxyAuthentication  - Proxy auth state: UNCHALLENGED
2352 [http-nio-8080-exec-4] DEBUG org.apache.http.impl.client.DefaultHttpClient  - Attempt 1 to execute request
2352 [http-nio-8080-exec-4] DEBUG org.apache.http.impl.conn.DefaultClientConnection  - Sending request: POST /db/data/transaction/54/commit HTTP/1.1
2352 [http-nio-8080-exec-4] DEBUG org.apache.http.wire  -  >> "POST /db/data/transaction/54/commit HTTP/1.1[\r][\n]"
2352 [http-nio-8080-exec-4] DEBUG org.apache.http.wire  -  >> "Accept: application/json[\r][\n]"
2352 [http-nio-8080-exec-4] DEBUG org.apache.http.wire  -  >> "Accept-Encoding: gzip, deflate[\r][\n]"
2352 [http-nio-8080-exec-4] DEBUG org.apache.http.wire  -  >> "Authorization: Basic bmVvNGo6Z2VuaXZpdHk=[\r][\n]"
2352 [http-nio-8080-exec-4] DEBUG org.apache.http.wire  -  >> "X-Stream: true[\r][\n]"
2352 [http-nio-8080-exec-4] DEBUG org.apache.http.wire  -  >> "Content-Length: 0[\r][\n]"
2352 [http-nio-8080-exec-4] DEBUG org.apache.http.wire  -  >> "Host: localhost:7474[\r][\n]"
2352 [http-nio-8080-exec-4] DEBUG org.apache.http.wire  -  >> "Connection: Keep-Alive[\r][\n]"
2352 [http-nio-8080-exec-4] DEBUG org.apache.http.wire  -  >> "[\r][\n]"
2352 [http-nio-8080-exec-4] DEBUG org.apache.http.headers  - >> POST /db/data/transaction/54/commit HTTP/1.1
2352 [http-nio-8080-exec-4] DEBUG org.apache.http.headers  - >> Accept: application/json
2352 [http-nio-8080-exec-4] DEBUG org.apache.http.headers  - >> Accept-Encoding: gzip, deflate
2352 [http-nio-8080-exec-4] DEBUG org.apache.http.headers  - >> Authorization: Basic bmVvNGo6Z2VuaXZpdHk=
2352 [http-nio-8080-exec-4] DEBUG org.apache.http.headers  - >> X-Stream: true
2352 [http-nio-8080-exec-4] DEBUG org.apache.http.headers  - >> Content-Length: 0
2352 [http-nio-8080-exec-4] DEBUG org.apache.http.headers  - >> Host: localhost:7474
2352 [http-nio-8080-exec-4] DEBUG org.apache.http.headers  - >> Connection: Keep-Alive
2354 [http-nio-8080-exec-4] DEBUG org.apache.http.wire  -  << "HTTP/1.1 404 Not Found[\r][\n]"
2354 [http-nio-8080-exec-4] DEBUG org.apache.http.wire  -  << "Date: Tue, 03 Oct 2017 09:01:10 GMT[\r][\n]"
2354 [http-nio-8080-exec-4] DEBUG org.apache.http.wire  -  << "Content-Type: application/json[\r][\n]"
2354 [http-nio-8080-exec-4] DEBUG org.apache.http.wire  -  << "Access-Control-Allow-Origin: *[\r][\n]"
2354 [http-nio-8080-exec-4] DEBUG org.apache.http.wire  -  << "Content-Length: 178[\r][\n]"
2354 [http-nio-8080-exec-4] DEBUG org.apache.http.wire  -  << "Server: Jetty(9.2.z-SNAPSHOT)[\r][\n]"
2354 [http-nio-8080-exec-4] DEBUG org.apache.http.wire  -  << "[\r][\n]"
2354 [http-nio-8080-exec-4] DEBUG org.apache.http.impl.conn.DefaultClientConnection  - Receiving response: HTTP/1.1 404 Not Found
2354 [http-nio-8080-exec-4] DEBUG org.apache.http.headers  - << HTTP/1.1 404 Not Found
2354 [http-nio-8080-exec-4] DEBUG org.apache.http.headers  - << Date: Tue, 03 Oct 2017 09:01:10 GMT
2354 [http-nio-8080-exec-4] DEBUG org.apache.http.headers  - << Content-Type: application/json
2354 [http-nio-8080-exec-4] DEBUG org.apache.http.headers  - << Access-Control-Allow-Origin: *
2354 [http-nio-8080-exec-4] DEBUG org.apache.http.headers  - << Content-Length: 178
2354 [http-nio-8080-exec-4] DEBUG org.apache.http.headers  - << Server: Jetty(9.2.z-SNAPSHOT)
2354 [http-nio-8080-exec-4] DEBUG org.apache.http.impl.client.DefaultHttpClient  - Connection can be kept alive indefinitely
2354 [http-nio-8080-exec-4] DEBUG org.apache.http.wire  -  << "{"results":[],"errors":[{"code":"Neo.ClientError.Transaction.TransactionNotFound","message":"Unrecognized transaction id. Transaction may have timed out and been rolled back."}]}"
2354 [http-nio-8080-exec-4] DEBUG org.apache.http.impl.conn.PoolingClientConnectionManager  - Connection [id: 1][route: {}->http://localhost:7474] can be kept alive indefinitely
2354 [http-nio-8080-exec-4] DEBUG org.apache.http.impl.conn.PoolingClientConnectionManager  - Connection released: [id: 1][route: {}->http://localhost:7474][total kept alive: 1; route allocated: 2 of 10; total allocated: 2 of 10]
2355 [http-nio-8080-exec-4] DEBUG org.hibernate.resource.jdbc.internal.LogicalConnectionManagedImpl  - Initiating JDBC connection release from afterTransaction
18718 [Finalizer] DEBUG org.apache.http.wire  -  << "{"password_change_required":false,"password_change":"http://localhost:7474/user/neo4j/password","username":"neo4j"}"
18719 [Finalizer] DEBUG org.apache.http.impl.conn.PoolingClientConnectionManager  - Connection [id: 0][route: {}->http://localhost:7474] can be kept alive indefinitely
18719 [Finalizer] DEBUG org.apache.http.impl.conn.PoolingClientConnectionManager  - Connection released: [id: 0][route: {}->http://localhost:7474][total kept alive: 2; route allocated: 2 of 10; total allocated: 2 of 10]

此外，我注意到的另一件事是，当我第一次发送JSON时，我会得到上面的日志。当我第二次发送它时，每行都会打印两次；当我第三次发送它时，每行都会打印三次，以此类推... 我不确定是什么原因导致了这个问题，但这可能是问题的原因。

- Porjaz

---

在你的dao中，为什么要创建一个新的Person对象呢？你可以直接将参数中的person对象传递并持久化它。 - Vivek Singh

@VivekSingh 我正在遵循这个指南http://www.topjavatutorial.com/frameworks/hibernate/adding-hibernate-dao-layer-in-existing-maven-project/，它是用新对象的方式完成的。我从参数中传递了`person`对象，但我仍然得到“状态：200 OK”，并且对象没有保存。 - Porjaz

@pruntlar 是的，我已经刷新了数据库并且多次重启了它。 - Porjaz

请移除您的DAO中的try-catch块，以获取有意义的错误消息/堆栈跟踪。 - user3151902

请看异常的第一部分：LockClient[6511] <-[:HELD_BY]- RWLock[SCHEMA(0), hash=110596439] <-[:WAITING_FOR]- LockClient[6495]，它说明客户端6495正在等待被客户端6511持有的锁。看起来多个客户端正在以无法被Neo4j解决的方式访问数据库。 - user3151902

Answer 1

我通过将tomcat 8.5更换为wildfly 9来解决了我的问题。尽管所有其他操作都正常工作，但插入人员数据时出现了问题，至今我仍不确定 tomcat 的问题所在。

- Porjaz

Answer 2

我猜测问题是

@GeneratedValue(strategy = GenerationType.AUTO)

无法找到适当的方法来创建密钥。 建议尝试类似这样的方式：

@SequenceGenerator(name = "sequence_generator_name", sequenceName = "sequence_name", allocationSize = 1)
@GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "sequence_generator_name")

使用数据库序列来创建键。如果您不使用模式自动更新，则必须手动创建序列。语法细节取决于您的数据库。

- Stas Shafeev

---

那不是问题。我已经按照你建议的方式尝试过了，但最终结果仍然相同。无论哪种方式，都会在数据库中创建一个 SEQUENCE 对象，并具有属性：sequence_name 和 next_val。因此，即使我只使用 @GeneratedValue(strategy = GenerationType.AUTO)，它也会自动使用 SEQUENCE 策略并创建 SEQUENCE 对象。 - Porjaz

对于误导，我很抱歉。 - Stas Shafeev

Answer 3

我认为我找到了错误，更改这些行：

em.persist(p);
em.flush();     
tx.commit();
em.clear(); 
em.close(); 
emf.close();

通过这些行：

em.persist(p);
em.flush();
em.close();
tx.commit();
emf.close();

- Halayem Anis

---

我已经更改了它们，但不幸的是实体仍未保存。如果有帮助的话，我可以提供整个代码？ - Porjaz

我忘记了 emf.close()，再试一次，永不放弃 :) - Halayem Anis

尝试过了，还是没有效果。我猜问题出在自动生成的ID上。正如帖子中提到的，如果我删除注释并手动指定ID，则实体将被保存。此外，当我使用本地查询保存实体（并在查询中指定ID）时，实体也会被保存。 - Porjaz

你在数据库中创建了一个序列吗？ - Halayem Anis

是的，当我使用@GeneratedValue(strategy = GenerationType.AUTO)时，序列会自动在数据库中创建，并具有属性：sequence_name和next_val。因此，我认为这很好运行，因为日志显示已执行的查询以及生成的ID也在那里。 - Porjaz

Answer 4

替换这个：

catch ( Exception e ) {
    e.printStackTrace();
}

使用这个：

catch ( Exception e ) {
    throw new RuntimeException(e);
}

异常没有被重新抛出，因此就你的REST层而言，PersonDAO.addPerson已成功，并且它将生成一个OK响应。

- Martín Straus

---

当我替换catch块时，在get中只会得到以下堆栈跟踪信息：log4j:WARN No appenders could be found for logger (org.jboss.logging)。 log4j:WARN Please initialize the log4j system properly. log4j:WARN See http://logging.apache.org/log4j/1.2/faq.html#noconfig for more info. - Porjaz

好的，看起来你报告的原始问题（关于状态200的问题）已经通过我的建议解决了。现在你又发现了另一个问题；你应该发布另一个问题，以免污染这个问题。 - Martín Straus

实际上问题还没有解决。我仍然无法将对象保存到数据库中。我在我的catch块中得到了与您建议的相同的堆栈跟踪。 - Porjaz

好的，你编辑了你的问题并在之后添加了另一半的问题，所以...无论如何，我不能帮你解决Neo4j的问题。你添加的堆栈跟踪似乎没有来自Neo4j的任何错误消息，除了关于事务的消息，而那个似乎是结果，而不是原因。如果根本错误被隐藏起来，你可能需要添加更多的日志记录。 - Martín Straus