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我如何解决这个问题？？java.lang.ClassCastException

java hibernate web-services spring-mvc spring-boot

我如何解决这个问题？？java.lang.ClassCastException,java,hibernate,web-services,spring-mvc,spring-boot,Java,Hibernate,Web Services,Spring Mvc,Spring Boot,白标错误页 此应用程序没有/error的显式映射，因此您将其视为回退。 2018年8月13日星期一21:40:42 出现意外错误（类型=内部服务器错误，状态=500）。 数据库测试。讲师不能强制转换为数据库测试。讲师 import org.hibernate.Session; import org.hibernate.SessionFactory; import org.springframework.beans.factory.annotation.Autowired; import org.

白标错误页
此应用程序没有/error的显式映射，因此您将其视为回退。

2018年8月13日星期一21:40:42
出现意外错误（类型=内部服务器错误，状态=500）。
数据库测试。讲师不能强制转换为数据库测试。讲师

import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;
import DataBaseTest.Instructor;

    @RestController
    public class TestWebService {

        @Autowired
        private  SessionFactory sessionFactory ;

        @GetMapping(path="/user")
        public Instructor getUser(){
            Session session = sessionFactory.getCurrentSession();
            session.beginTransaction();
            Instructor instructor = (Instructor) session.get(Instructor.class,1);
            System.out.println(instructor);
            return instructor;
        }
----------------------------班主任------------------------

@Entity
@Table(name="instructor")
public class Instructor {
    @Id
    @GeneratedValue(strategy=GenerationType.IDENTITY)
    @Column(name="id")
    private int id ;

    @Column(name="first_name")
    private String firstName ;

    @Column(name="last_name")
    private String lastName ;

    @Column(name="email")
    private String email ;

    @OneToOne(cascade=CascadeType.ALL)
    @JoinColumn(name="instructor_detail_id")
    InstructorDetails instructorDetails ;

    public Instructor(){

    }

    public Instructor(String firstName, String lastName, String email) {
        super();
        this.firstName = firstName;
        this.lastName = lastName;
        this.email = email;
    }

    public int getId() {
        return id;
    }

    public String getFirstName() {
        return firstName;
    }

    public void setFirstName(String firstName) {
        this.firstName = firstName;
    }

    public String getLastName() {
        return lastName;
    }

    public void setLastName(String lastName) {
        this.lastName = lastName;
    }

    public String getEmail() {
        return email;
    }

    public void setEmail(String email) {
        this.email = email;
    }

    public InstructorDetails getInstructorDetails() {
        return instructorDetails;
    }

    public void setInstructorDetails(InstructorDetails instructorDetails) {
        this.instructorDetails = instructorDetails;
    }

    @Override
    public String toString() {
        return "Instructor [id=" + id + ", firstName=" + firstName + ", lastName=" + lastName + ", email=" + email
                + ", instructorDetails=" + instructorDetails + "]";
    }


}

@Entity
@Table(name="instructor_detail")
public class InstructorDetails {

    @Id
    @GeneratedValue(strategy=GenerationType.IDENTITY)
    @Column(name="id")
    private int id ;

    @Column(name="youtube_channel")
    private String youtubeChanel ;

    @Column(name="hobby")
    private String hobby ;

    public InstructorDetails(){

    }

    public InstructorDetails(String youtubeChanel, String hobby) {
        super();
        this.youtubeChanel = youtubeChanel;
        this.hobby = hobby;
    }

    public int getId() {
        return id;
    }

    public String getYoutubeChanel() {
        return youtubeChanel;
    }

    public void setYoutubeChanel(String youtubeChanel) {
        this.youtubeChanel = youtubeChanel;
    }

    public String getHobby() {
        return hobby;
    }

    public void setHobby(String hobby) {
        this.hobby = hobby;
    }

    @Override
    public String toString() {
        return "InstructorDetails [id=" + id + ", youtubeChanel=" + youtubeChanel + ", hobby=" + hobby + "]";
    }



}

<!DOCTYPE hibernate-configuration PUBLIC
        "-//Hibernate/Hibernate Configuration DTD 3.0//EN"
        "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">

<hibernate-configuration>

    <session-factory>

        <!-- JDBC Database connection settings -->
        <property name="connection.driver_class">com.mysql.jdbc.Driver</property>
        <property name="connection.url">jdbc:mysql://localhost:3306/hb-01-one-to-one-uni?useSSL=false</property>
        <property name="connection.username">hbstudent</property>
        <property name="connection.password">hbstudent</property>

        <!-- JDBC connection pool settings ... using built-in test pool -->
        <property name="connection.pool_size">100</property>

        <!-- Select our SQL dialect -->
        <property name="dialect">org.hibernate.dialect.MySQLDialect</property>

        <!-- Echo the SQL to stdout -->
        <property name="show_sql">true</property>

        <!-- Set the current session context -->
        <property name="current_session_context_class">thread</property>

    </session-factory>

</hibernate-configuration>
----------------------------课堂讲师详细信息------------------------

@Entity
@Table(name="instructor")
public class Instructor {
    @Id
    @GeneratedValue(strategy=GenerationType.IDENTITY)
    @Column(name="id")
    private int id ;

    @Column(name="first_name")
    private String firstName ;

    @Column(name="last_name")
    private String lastName ;

    @Column(name="email")
    private String email ;

    @OneToOne(cascade=CascadeType.ALL)
    @JoinColumn(name="instructor_detail_id")
    InstructorDetails instructorDetails ;

    public Instructor(){

    }

    public Instructor(String firstName, String lastName, String email) {
        super();
        this.firstName = firstName;
        this.lastName = lastName;
        this.email = email;
    }

    public int getId() {
        return id;
    }

    public String getFirstName() {
        return firstName;
    }

    public void setFirstName(String firstName) {
        this.firstName = firstName;
    }

    public String getLastName() {
        return lastName;
    }

    public void setLastName(String lastName) {
        this.lastName = lastName;
    }

    public String getEmail() {
        return email;
    }

    public void setEmail(String email) {
        this.email = email;
    }

    public InstructorDetails getInstructorDetails() {
        return instructorDetails;
    }

    public void setInstructorDetails(InstructorDetails instructorDetails) {
        this.instructorDetails = instructorDetails;
    }

    @Override
    public String toString() {
        return "Instructor [id=" + id + ", firstName=" + firstName + ", lastName=" + lastName + ", email=" + email
                + ", instructorDetails=" + instructorDetails + "]";
    }


}

@Entity
@Table(name="instructor_detail")
public class InstructorDetails {

    @Id
    @GeneratedValue(strategy=GenerationType.IDENTITY)
    @Column(name="id")
    private int id ;

    @Column(name="youtube_channel")
    private String youtubeChanel ;

    @Column(name="hobby")
    private String hobby ;

    public InstructorDetails(){

    }

    public InstructorDetails(String youtubeChanel, String hobby) {
        super();
        this.youtubeChanel = youtubeChanel;
        this.hobby = hobby;
    }

    public int getId() {
        return id;
    }

    public String getYoutubeChanel() {
        return youtubeChanel;
    }

    public void setYoutubeChanel(String youtubeChanel) {
        this.youtubeChanel = youtubeChanel;
    }

    public String getHobby() {
        return hobby;
    }

    public void setHobby(String hobby) {
        this.hobby = hobby;
    }

    @Override
    public String toString() {
        return "InstructorDetails [id=" + id + ", youtubeChanel=" + youtubeChanel + ", hobby=" + hobby + "]";
    }



}

<!DOCTYPE hibernate-configuration PUBLIC
        "-//Hibernate/Hibernate Configuration DTD 3.0//EN"
        "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">

<hibernate-configuration>

    <session-factory>

        <!-- JDBC Database connection settings -->
        <property name="connection.driver_class">com.mysql.jdbc.Driver</property>
        <property name="connection.url">jdbc:mysql://localhost:3306/hb-01-one-to-one-uni?useSSL=false</property>
        <property name="connection.username">hbstudent</property>
        <property name="connection.password">hbstudent</property>

        <!-- JDBC connection pool settings ... using built-in test pool -->
        <property name="connection.pool_size">100</property>

        <!-- Select our SQL dialect -->
        <property name="dialect">org.hibernate.dialect.MySQLDialect</property>

        <!-- Echo the SQL to stdout -->
        <property name="show_sql">true</property>

        <!-- Set the current session context -->
        <property name="current_session_context_class">thread</property>

    </session-factory>

</hibernate-configuration>
---------------------------应用----------------

@Entity
@Table(name="instructor")
public class Instructor {
    @Id
    @GeneratedValue(strategy=GenerationType.IDENTITY)
    @Column(name="id")
    private int id ;

    @Column(name="first_name")
    private String firstName ;

    @Column(name="last_name")
    private String lastName ;

    @Column(name="email")
    private String email ;

    @OneToOne(cascade=CascadeType.ALL)
    @JoinColumn(name="instructor_detail_id")
    InstructorDetails instructorDetails ;

    public Instructor(){

    }

    public Instructor(String firstName, String lastName, String email) {
        super();
        this.firstName = firstName;
        this.lastName = lastName;
        this.email = email;
    }

    public int getId() {
        return id;
    }

    public String getFirstName() {
        return firstName;
    }

    public void setFirstName(String firstName) {
        this.firstName = firstName;
    }

    public String getLastName() {
        return lastName;
    }

    public void setLastName(String lastName) {
        this.lastName = lastName;
    }

    public String getEmail() {
        return email;
    }

    public void setEmail(String email) {
        this.email = email;
    }

    public InstructorDetails getInstructorDetails() {
        return instructorDetails;
    }

    public void setInstructorDetails(InstructorDetails instructorDetails) {
        this.instructorDetails = instructorDetails;
    }

    @Override
    public String toString() {
        return "Instructor [id=" + id + ", firstName=" + firstName + ", lastName=" + lastName + ", email=" + email
                + ", instructorDetails=" + instructorDetails + "]";
    }


}

@Entity
@Table(name="instructor_detail")
public class InstructorDetails {

    @Id
    @GeneratedValue(strategy=GenerationType.IDENTITY)
    @Column(name="id")
    private int id ;

    @Column(name="youtube_channel")
    private String youtubeChanel ;

    @Column(name="hobby")
    private String hobby ;

    public InstructorDetails(){

    }

    public InstructorDetails(String youtubeChanel, String hobby) {
        super();
        this.youtubeChanel = youtubeChanel;
        this.hobby = hobby;
    }

    public int getId() {
        return id;
    }

    public String getYoutubeChanel() {
        return youtubeChanel;
    }

    public void setYoutubeChanel(String youtubeChanel) {
        this.youtubeChanel = youtubeChanel;
    }

    public String getHobby() {
        return hobby;
    }

    public void setHobby(String hobby) {
        this.hobby = hobby;
    }

    @Override
    public String toString() {
        return "InstructorDetails [id=" + id + ", youtubeChanel=" + youtubeChanel + ", hobby=" + hobby + "]";
    }



}

<!DOCTYPE hibernate-configuration PUBLIC
        "-//Hibernate/Hibernate Configuration DTD 3.0//EN"
        "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">

<hibernate-configuration>

    <session-factory>

        <!-- JDBC Database connection settings -->
        <property name="connection.driver_class">com.mysql.jdbc.Driver</property>
        <property name="connection.url">jdbc:mysql://localhost:3306/hb-01-one-to-one-uni?useSSL=false</property>
        <property name="connection.username">hbstudent</property>
        <property name="connection.password">hbstudent</property>

        <!-- JDBC connection pool settings ... using built-in test pool -->
        <property name="connection.pool_size">100</property>

        <!-- Select our SQL dialect -->
        <property name="dialect">org.hibernate.dialect.MySQLDialect</property>

        <!-- Echo the SQL to stdout -->
        <property name="show_sql">true</property>

        <!-- Set the current session context -->
        <property name="current_session_context_class">thread</property>

    </session-factory>

</hibernate-configuration>
-----------------------------hibernate.cfg2.xml------------------------------

@Entity
@Table(name="instructor")
public class Instructor {
    @Id
    @GeneratedValue(strategy=GenerationType.IDENTITY)
    @Column(name="id")
    private int id ;

    @Column(name="first_name")
    private String firstName ;

    @Column(name="last_name")
    private String lastName ;

    @Column(name="email")
    private String email ;

    @OneToOne(cascade=CascadeType.ALL)
    @JoinColumn(name="instructor_detail_id")
    InstructorDetails instructorDetails ;

    public Instructor(){

    }

    public Instructor(String firstName, String lastName, String email) {
        super();
        this.firstName = firstName;
        this.lastName = lastName;
        this.email = email;
    }

    public int getId() {
        return id;
    }

    public String getFirstName() {
        return firstName;
    }

    public void setFirstName(String firstName) {
        this.firstName = firstName;
    }

    public String getLastName() {
        return lastName;
    }

    public void setLastName(String lastName) {
        this.lastName = lastName;
    }

    public String getEmail() {
        return email;
    }

    public void setEmail(String email) {
        this.email = email;
    }

    public InstructorDetails getInstructorDetails() {
        return instructorDetails;
    }

    public void setInstructorDetails(InstructorDetails instructorDetails) {
        this.instructorDetails = instructorDetails;
    }

    @Override
    public String toString() {
        return "Instructor [id=" + id + ", firstName=" + firstName + ", lastName=" + lastName + ", email=" + email
                + ", instructorDetails=" + instructorDetails + "]";
    }


}

@Entity
@Table(name="instructor_detail")
public class InstructorDetails {

    @Id
    @GeneratedValue(strategy=GenerationType.IDENTITY)
    @Column(name="id")
    private int id ;

    @Column(name="youtube_channel")
    private String youtubeChanel ;

    @Column(name="hobby")
    private String hobby ;

    public InstructorDetails(){

    }

    public InstructorDetails(String youtubeChanel, String hobby) {
        super();
        this.youtubeChanel = youtubeChanel;
        this.hobby = hobby;
    }

    public int getId() {
        return id;
    }

    public String getYoutubeChanel() {
        return youtubeChanel;
    }

    public void setYoutubeChanel(String youtubeChanel) {
        this.youtubeChanel = youtubeChanel;
    }

    public String getHobby() {
        return hobby;
    }

    public void setHobby(String hobby) {
        this.hobby = hobby;
    }

    @Override
    public String toString() {
        return "InstructorDetails [id=" + id + ", youtubeChanel=" + youtubeChanel + ", hobby=" + hobby + "]";
    }



}

<!DOCTYPE hibernate-configuration PUBLIC
        "-//Hibernate/Hibernate Configuration DTD 3.0//EN"
        "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">

<hibernate-configuration>

    <session-factory>

        <!-- JDBC Database connection settings -->
        <property name="connection.driver_class">com.mysql.jdbc.Driver</property>
        <property name="connection.url">jdbc:mysql://localhost:3306/hb-01-one-to-one-uni?useSSL=false</property>
        <property name="connection.username">hbstudent</property>
        <property name="connection.password">hbstudent</property>

        <!-- JDBC connection pool settings ... using built-in test pool -->
        <property name="connection.pool_size">100</property>

        <!-- Select our SQL dialect -->
        <property name="dialect">org.hibernate.dialect.MySQLDialect</property>

        <!-- Echo the SQL to stdout -->
        <property name="show_sql">true</property>

        <!-- Set the current session context -->
        <property name="current_session_context_class">thread</property>

    </session-factory>

</hibernate-configuration>
我能想到的唯一可能的解释是，这是一个类加载器泄漏，如中所述

见该答复中的评论：-

@Musa YUVACI-ClassLoader这种形式的泄漏通常是由于 服务器作用域类加载器中保存的引用（或 app server或开发者在WARs/EAR之外添加库。）– 麦克道尔2011年5月31日9:08

@麦克道尔：谢谢你的回复，现在可以用了。 在WARs之外添加库时出现问题。那以后呢 从glassfish服务器中删除库后，它就可以正常工作了穆萨尤瓦奇 2011年5月31日13:35

您确定消息是“无法将X强制转换为X”（即相同的类名，而不是实际的X）？因为这没有任何意义。是的，我复制了错误的原样：/当我使用MainClass进行测试时，sessionFactory使用相同的代码正确返回讲师对象！！检查这些类的导入，这看起来像@zaplDataBaseTest中提到的两个同名的不同类。讲师不能转换为DataBaseTest。讲师包名称为“DataBaseTest”，因此是同一个类