Question

我尝试通过jackson实现并反序列化LocalDateTime。我使用hibernate + restful webservices。这是我的实体：

@Entity
@Table(name = "USERS")
@NamedQueries(value = { 
    @NamedQuery(name = "getUser", query = "from User user where userId = ?") 
})
public class User extends ResourceSupport implements Serializable{

@Id
@GeneratedValue(strategy = GenerationType.AUTO)
@Column(name = "USER_ID")
private long userId;

@Column(name = "USER_NAME")
private String userName;

@Column(name = "USER_CREATED")

@JsonSerialize(using = LocalDateTimeSerializer.class)
@JsonDeserialize(using = LocalDateTimeDeserializer.class)

private LocalDateTime userCreated;

@Column(name = "USER_PHONE")
private String userPhone;


public User(){}

@JsonCreator
public User(@JsonProperty("userId") long userId,
            @JsonProperty("userName") String userName, 
            @JsonProperty("phone") String phone) {
    super();
    this.userId = userId;
    this.userName = userName;
    this.userPhone = phone;
    this.userCreated = LocalDateTime.now();
}
public long getUserId() {
    return userId;
}
public void setUserId(long userId) {
    this.userId = userId;
}
public String getUserName() {
    return userName;
}
public void setUserName(String userName) {
    this.userName = userName;
}

public LocalDateTime getUserCreated() {
    return userCreated;
}

public void setUserCreated(LocalDateTime userCreated) {
    this.userCreated = userCreated;
}

public String getUserPhone() {
    return userPhone;
}

public void setUserPhone(String userPhone) {
    this.userPhone = userPhone;
}

@Override
public boolean equals(Object user){
    boolean result = false;
    if((user==null)||!(user instanceof User))
        result = false;
    else{
        User otherUser = (User)user;
        result = this.getUserId() == otherUser.getUserId() &&
                 this.getUserName() == otherUser.getUserName() &&
                 this.getUserPhone() == otherUser.getUserPhone()&&
                 this.getUserCreated() == otherUser.getUserCreated();
    }
    return result;
}

@Override
public int hashCode(){
    return Long.hashCode(userId) ;
}

这是我的序列化器：

public class LocalDateTimeSerializer extends JsonSerializer<LocalDateTime>{

    @Override
    public void serialize(LocalDateTime arg0, JsonGenerator arg1, SerializerProvider arg2)
            throws IOException, JsonProcessingException {
        // TODO Auto-generated method stub
        DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss");
        String formattedDateTime = arg0.format(formatter);
        arg1.writeString(formattedDateTime);
    }

}

这是我的解串器：

public class LocalDateTimeDeserializer extends JsonDeserializer<LocalDateTime> {

    @Override
    public LocalDateTime deserialize(JsonParser arg0, DeserializationContext arg1)
            throws IOException, JsonProcessingException {
        // TODO Auto-generated method stub
        DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss");
        LocalDateTime localDateTime = LocalDateTime.parse(arg0.getText(), formatter);
        return localDateTime;
    }

}

这是我的DAO课程：

@Repository
public class UserDAOImpl implements UserDAO{

@Autowired
private SessionFactory sessionFactory;

public UserDAOImpl(){}
public UserDAOImpl(SessionFactory sessionFactory){
    this.sessionFactory = sessionFactory;
}


@Override
public User getUser(long userId) {
    //Session session = sessionFactory.getCurrentSession();
    Session session = sessionFactory.openSession();
    Query query = session.getNamedQuery("getUser");
    query.setParameter(0, userId);

    return (User)query.uniqueResult();// this string invokes error
}
@Override
public void addUser(User user) {
    // TODO Auto-generated method stub
    Session session = sessionFactory.openSession();
    user.setUserCreated(LocalDateTime.now());
    session.save(user);
    session.flush();
    session.close();
}

这是我保存的用户的USER_CREATED字段的值：

  ACED00057372000D6A6176612E74696D652E536572955D84BA1B2248B20C00007870770E05000007E004110F261012C684C078

当我将用户添加到db时，添加操作正在成功执行，但是当我尝试从DB获取用户时，我收到错误：

java.io.StreamCorruptedException: invalid stream header: 41434544
at java.io.ObjectInputStream.readStreamHeader(ObjectInputStream.java:806) ~[na:1.8.0_73]
at java.io.ObjectInputStream.<init>(ObjectInputStream.java:299) ~[na:1.8.0_73]
at org.hibernate.internal.util.SerializationHelper$CustomObjectInputStream.<init>(SerializationHelper.java:309) ~[hibernate-core-5.0.5.Final.jar:5.0.5.Final]
at org.hibernate.internal.util.SerializationHelper$CustomObjectInputStream.<init>(SerializationHelper.java:299) ~[hibernate-core-5.0.5.Final.jar:5.0.5.Final]
at org.hibernate.internal.util.SerializationHelper.doDeserialize(SerializationHelper.java:218) ~[hibernate-core-5.0.5.Final.jar:5.0.5.Final]
at org.hibernate.internal.util.SerializationHelper.deserialize(SerializationHelper.java:287) ~[hibernate-core-5.0.5.Final.jar:5.0.5.Final]
at org.hibernate.type.descriptor.java.SerializableTypeDescriptor.fromBytes(SerializableTypeDescriptor.java:138) ~[hibernate-core-5.0.5.Final.jar:5.0.5.Final]
at org.hibernate.type.descriptor.java.SerializableTypeDescriptor.wrap(SerializableTypeDescriptor.java:113) ~[hibernate-core-5.0.5.Final.jar:5.0.5.Final]
at org.hibernate.type.descriptor.java.SerializableTypeDescriptor.wrap(SerializableTypeDescriptor.java:27) ~[hibernate-core-5.0.5.Final.jar:5.0.5.Final]
at org.hibernate.type.descriptor.sql.VarbinaryTypeDescriptor$2.doExtract(VarbinaryTypeDescriptor.java:53) ~[hibernate-core-5.0.5.Final.jar:5.0.5.Final]
at org.hibernate.type.descriptor.sql.BasicExtractor.extract(BasicExtractor.java:47) ~[hibernate-core-5.0.5.Final.jar:5.0.5.Final]
at org.hibernate.type.AbstractStandardBasicType.nullSafeGet(AbstractStandardBasicType.java:238) ~[hibernate-core-5.0.5.Final.jar:5.0.5.Final]
at org.hibernate.type.AbstractStandardBasicType.nullSafeGet(AbstractStandardBasicType.java:234) ~[hibernate-core-5.0.5.Final.jar:5.0.5.Final]
at org.hibernate.type.AbstractStandardBasicType.nullSafeGet(AbstractStandardBasicType.java:224) ~[hibernate-core-5.0.5.Final.jar:5.0.5.Final]
at org.hibernate.type.AbstractStandardBasicType.hydrate(AbstractStandardBasicType.java:300) ~[hibernate-core-5.0.5.Final.jar:5.0.5.Final]
at org.hibernate.persister.entity.AbstractEntityPersister.hydrate(AbstractEntityPersister.java:2727) ~[hibernate-core-5.0.5.Final.jar:5.0.5.Final]
at org.hibernate.loader.Loader.loadFromResultSet(Loader.java:1728) ~[hibernate-core-5.0.5.Final.jar:5.0.5.Final]
at org.hibernate.loader.Loader.instanceNotYetLoaded(Loader.java:1654) ~[hibernate-core-5.0.5.Final.jar:5.0.5.Final]
at org.hibernate.loader.Loader.getRow(Loader.java:1543) ~[hibernate-core-5.0.5.Final.jar:5.0.5.Final]
at org.hibernate.loader.Loader.getRowFromResultSet(Loader.java:727) ~[hibernate-core-5.0.5.Final.jar:5.0.5.Final]
at org.hibernate.loader.Loader.processResultSet(Loader.java:972) ~[hibernate-core-5.0.5.Final.jar:5.0.5.Final]
at org.hibernate.loader.Loader.doQuery(Loader.java:930) ~[hibernate-core-5.0.5.Final.jar:5.0.5.Final]
at org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:336) ~[hibernate-core-5.0.5.Final.jar:5.0.5.Final]
at org.hibernate.loader.Loader.doList(Loader.java:2611) ~[hibernate-core-5.0.5.Final.jar:5.0.5.Final]
at org.hibernate.loader.Loader.doList(Loader.java:2594) ~[hibernate-core-5.0.5.Final.jar:5.0.5.Final]
at org.hibernate.loader.Loader.listIgnoreQueryCache(Loader.java:2423) ~[hibernate-core-5.0.5.Final.jar:5.0.5.Final]
at org.hibernate.loader.Loader.list(Loader.java:2418) ~[hibernate-core-5.0.5.Final.jar:5.0.5.Final]
at org.hibernate.loader.hql.QueryLoader.list(QueryLoader.java:501) ~[hibernate-core-5.0.5.Final.jar:5.0.5.Final]
at org.hibernate.hql.internal.ast.QueryTranslatorImpl.list(QueryTranslatorImpl.java:371) ~[hibernate-core-5.0.5.Final.jar:5.0.5.Final]
at org.hibernate.engine.query.spi.HQLQueryPlan.performList(HQLQueryPlan.java:216) ~[hibernate-core-5.0.5.Final.jar:5.0.5.Final]
at org.hibernate.internal.SessionImpl.list(SessionImpl.java:1326) ~[hibernate-core-5.0.5.Final.jar:5.0.5.Final]
at org.hibernate.internal.QueryImpl.list(QueryImpl.java:87) ~[hibernate-core-5.0.5.Final.jar:5.0.5.Final]
at org.hibernate.internal.AbstractQueryImpl.uniqueResult(AbstractQueryImpl.java:960) ~[hibernate-core-5.0.5.Final.jar:5.0.5.Final]
at org.company.dao.UserDAOImpl.getUser(UserDAOImpl.java:30) ~[classes/:na]
at org.company.dao.UserDAOImpl$$FastClassBySpringCGLIB$$d4b6a590.invoke(<generated>) ~[classes/:na]
at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:204) ~[spring-core-4.2.5.RELEASE.jar:4.2.5.RELEASE]
at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:720) ~[spring-aop-4.2.5.RELEASE.jar:4.2.5.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:157) ~[spring-aop-4.2.5.RELEASE.jar:4.2.5.RELEASE]
at org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.invoke(PersistenceExceptionTranslationInterceptor.java:136) ~[spring-tx-4.2.5.RELEASE.jar:4.2.5.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179) ~[spring-aop-4.2.5.RELEASE.jar:4.2.5.RELEASE]
at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:655) ~[spring-aop-4.2.5.RELEASE.jar:4.2.5.RELEASE]
at org.company.dao.UserDAOImpl$$EnhancerBySpringCGLIB$$21463096.getUser(<generated>) ~[classes/:na]
at org.company.service.UserServiceImpl.getUser(UserServiceImpl.java:39) ~[classes/:na]
at org.company.controller.UserController.getUser(UserController.java:43) ~[classes/:na]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_73]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_73]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_73]
at java.lang.reflect.Method.invoke(Method.java:497) ~[na:1.8.0_73]
at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:221) ~[spring-web-4.2.5.RELEASE.jar:4.2.5.RELEASE]
at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:136) ~[spring-web-4.2.5.RELEASE.jar:4.2.5.RELEASE]
at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:110) ~[spring-webmvc-4.2.5.RELEASE.jar:4.2.5.RELEASE]
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:817) ~[spring-webmvc-4.2.5.RELEASE.jar:4.2.5.RELEASE]
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:731) ~[spring-webmvc-4.2.5.RELEASE.jar:4.2.5.RELEASE]
at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:85) ~[spring-webmvc-4.2.5.RELEASE.jar:4.2.5.RELEASE]
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:959) ~[spring-webmvc-4.2.5.RELEASE.jar:4.2.5.RELEASE]
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:893) ~[spring-webmvc-4.2.5.RELEASE.jar:4.2.5.RELEASE]
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:968) ~[spring-webmvc-4.2.5.RELEASE.jar:4.2.5.RELEASE]
at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:859) ~[spring-webmvc-4.2.5.RELEASE.jar:4.2.5.RELEASE]
at javax.servlet.http.HttpServlet.service(HttpServlet.java:622) ~[tomcat-embed-core-8.0.32.jar:8.0.32]
at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:844) ~[spring-webmvc-4.2.5.RELEASE.jar:4.2.5.RELEASE]
at javax.servlet.http.HttpServlet.service(HttpServlet.java:729) ~[tomcat-embed-core-8.0.32.jar:8.0.32]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:292) ~[tomcat-embed-core-8.0.32.jar:8.0.32]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207) ~[tomcat-embed-core-8.0.32.jar:8.0.32]
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) ~[tomcat-embed-websocket-8.0.32.jar:8.0.32]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:240) ~[tomcat-embed-core-8.0.32.jar:8.0.32]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207) ~[tomcat-embed-core-8.0.32.jar:8.0.32]
at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:99) ~[spring-web-4.2.5.RELEASE.jar:4.2.5.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.2.5.RELEASE.jar:4.2.5.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:240) ~[tomcat-embed-core-8.0.32.jar:8.0.32]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207) ~[tomcat-embed-core-8.0.32.jar:8.0.32]
at org.springframework.web.filter.HttpPutFormContentFilter.doFilterInternal(HttpPutFormContentFilter.java:87) ~[spring-web-4.2.5.RELEASE.jar:4.2.5.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.2.5.RELEASE.jar:4.2.5.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:240) ~[tomcat-embed-core-8.0.32.jar:8.0.32]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207) ~[tomcat-embed-core-8.0.32.jar:8.0.32]
at org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:77) ~[spring-web-4.2.5.RELEASE.jar:4.2.5.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.2.5.RELEASE.jar:4.2.5.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:240) ~[tomcat-embed-core-8.0.32.jar:8.0.32]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207) ~[tomcat-embed-core-8.0.32.jar:8.0.32]
at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:121) ~[spring-web-4.2.5.RELEASE.jar:4.2.5.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.2.5.RELEASE.jar:4.2.5.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:240) ~[tomcat-embed-core-8.0.32.jar:8.0.32]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207) ~[tomcat-embed-core-8.0.32.jar:8.0.32]
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:212) ~[tomcat-embed-core-8.0.32.jar:8.0.32]
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:106) [tomcat-embed-core-8.0.32.jar:8.0.32]
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502) [tomcat-embed-core-8.0.32.jar:8.0.32]
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:141) [tomcat-embed-core-8.0.32.jar:8.0.32]
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79) [tomcat-embed-core-8.0.32.jar:8.0.32]
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88) [tomcat-embed-core-8.0.32.jar:8.0.32]
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:522) [tomcat-embed-core-8.0.32.jar:8.0.32]
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1095) [tomcat-embed-core-8.0.32.jar:8.0.32]
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:672) [tomcat-embed-core-8.0.32.jar:8.0.32]
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1500) [tomcat-embed-core-8.0.32.jar:8.0.32]
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1456) [tomcat-embed-core-8.0.32.jar:8.0.32]
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) [na:1.8.0_73]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) [na:1.8.0_73]
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) [tomcat-embed-core-8.0.32.jar:8.0.32]
at java.lang.Thread.run(Thread.java:745) [na:1.8.0_73]

Answer 1

我知道这里发生了什么。这是线索。

数字41434544（十六进制）解码为字母＆＃34; A＆＃34;，＆＃34; C＆＃34;，＆＃34; E＆＃34;，＆＃34; D＆＃34 ;。
Java对象序列化以16位幻数开始，其十六进制值为ACED。（参考：https://docs.oracle.com/javase/6/docs/platform/serialization/spec/protocol.html）

所以看起来你做了以下事情：

您已将某个对象序列化为字节数组。
您已将字节数组转换为包含字节的十六进制表示的文本。
您已将该文本保存在某个表的VARCHAR（或类似）列中。
然后您检索了文本。
您已使用String.getBytes（...）将文本转换为字节。
您已尝试反序列化字节。

问题是第5步是错误的。您需要通过将字符串拆分为多对字符（十六进制数字）并将每对转换为一个字节来将文本转换为字节。

UPDATE - 显然，Hibernate正在幕后进行序列化，正确的解决方案是阻止它发生;见@JB Nizet的答案。

Answer 2

除非您将an additional jar添加到类路径中，否则Hibernate不支持LocalDateTime。

这意味着没有它，它会将LocalDateTime视为任何可序列化的类，并使用本机Java序列化将值存储到表的二进制列中。你真的，真的不想那样。

另外，不要将对象与==进行比较。请注意，这与JSON和Jackson没有任何关系。

java.io.StreamCorruptedException：无效的流标头：41434544

2 个答案: