java - hibernate PropertyAccessException : Error accessing field when use @ManyToMany

Question

我最近开始 hibernate ，在我的第一个项目中，我在使用 @ManyToMany 时给出了 PropertyAccessException: Error accessing field 我不知道发生了什么，我仔细检查了 getter 和 setter 是否是公共(public)的, 使用 MySQL 和 SQLite 并使用 hibernate v4 和 v5

菜单类:

package ir.sadeghpro.breakfast;

import javax.persistence.*;
import java.util.HashMap;
import java.util.Map;

@Entity
public class Product {

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private int id;
    private String name;
    private int count;
    private int min;
    private int type;
    @ManyToMany(targetEntity = Menu.class)
    private Map<Menu,Integer> menus = new HashMap<>();

    public Product(){}

    public Product(int type) {
        this.type = type;
    }

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getCount() {
        return count;
    }

    public void setCount(int count) {
        this.count = count;
    }

    public int getMin() {
        return min;
    }

    public void setMin(int min) {
        this.min = min;
    }

    public int getType() {
        return type;
    }

    public void setType(int type) {
        this.type = type;
    }

    public Map<Menu, Integer> getMenus() {
        return menus;
    }

    public void setMenus(Map<Menu, Integer> menus) {
        this.menus = menus;
    }
}

产品类别:

package ir.sadeghpro.breakfast;

import javax.persistence.*;
import java.util.HashMap;
import java.util.Map;

@Entity
public class Product {

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private int id;
    private String name;
    private int count;
    private int min;
    private int type;
    @ManyToMany(targetEntity = Menu.class)
    private Map<Menu,Integer> menus = new HashMap<>();

    public Product(){}

    public Product(int type) {
        this.type = type;
    }

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getCount() {
        return count;
    }

    public void setCount(int count) {
        this.count = count;
    }

    public int getMin() {
        return min;
    }

    public void setMin(int min) {
        this.min = min;
    }

    public int getType() {
        return type;
    }

    public void setType(int type) {
        this.type = type;
    }

    public Map<Menu, Integer> getMenus() {
        return menus;
    }

    public void setMenus(Map<Menu, Integer> menus) {
        this.menus = menus;
    }
}

hibernate 配置文件:

<?xml version='1.0' encoding='utf-8'?>
<!DOCTYPE hibernate-configuration PUBLIC
        "-//Hibernate/Hibernate Configuration DTD//EN"
        "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
    <session-factory>
        <property name="connection.url">jdbc:sqlite:sqlite.db</property>
        <property name="dialect">org.hibernate.dialect.SQLiteDialect</property>
        <property name="connection.driver_class">org.sqlite.JDBC</property>
        <property name="show_sql">true</property>
        <!-- <property name="connection.username"/> -->
        <!-- <property name="connection.password"/> -->

        <!-- DB schema will be updated if needed -->
        <property name="hbm2ddl.auto">create</property>
    </session-factory>
</hibernate-configuration>

hibernate 版本是 5.3.6.Final。错误是

Sep 07, 2018 11:47:10 AM org.hibernate.internal.ExceptionMapperStandardImpl mapManagedFlushFailure
ERROR: HHH000346: Error during managed flush [org.hibernate.property.access.spi.PropertyAccessException: Error accessing field [private int ir.sadeghpro.breakfast.Product.id] by reflection for persistent property [ir.sadeghpro.breakfast.Product#id] : 1]
Sep 07, 2018 11:47:10 AM org.hibernate.engine.jdbc.batch.internal.AbstractBatchImpl release
INFO: HHH000010: On release of batch it still contained JDBC statements
Exception in Application start method
java.lang.reflect.InvocationTargetException
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at com.sun.javafx.application.LauncherImpl.launchApplicationWithArgs(LauncherImpl.java:389)
    at com.sun.javafx.application.LauncherImpl.launchApplication(LauncherImpl.java:328)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at sun.launcher.LauncherHelper$FXHelper.main(LauncherHelper.java:767)
Caused by: java.lang.RuntimeException: Exception in Application start method
    at com.sun.javafx.application.LauncherImpl.launchApplication1(LauncherImpl.java:917)
    at com.sun.javafx.application.LauncherImpl.lambda$launchApplication$155(LauncherImpl.java:182)
    at java.lang.Thread.run(Thread.java:745)
Caused by: javafx.fxml.LoadException: 
/Users/peter/IdeaProjects/breakfast/target/classes/main.fxml

    at javafx.fxml.FXMLLoader.constructLoadException(FXMLLoader.java:2601)
    at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:2579)
    at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:2441)
    at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3214)
    at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3175)
    at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3148)
    at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3124)
    at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3104)
    at javafx.fxml.FXMLLoader.load(FXMLLoader.java:3097)
    at ir.sadeghpro.breakfast.Run.start(Run.java:13)
    at com.sun.javafx.application.LauncherImpl.lambda$launchApplication1$162(LauncherImpl.java:863)
    at com.sun.javafx.application.PlatformImpl.lambda$runAndWait$175(PlatformImpl.java:326)
    at com.sun.javafx.application.PlatformImpl.lambda$null$173(PlatformImpl.java:295)
    at java.security.AccessController.doPrivileged(Native Method)
    at com.sun.javafx.application.PlatformImpl.lambda$runLater$174(PlatformImpl.java:294)
    at com.sun.glass.ui.InvokeLaterDispatcher$Future.run(InvokeLaterDispatcher.java:95)
Caused by: javax.persistence.PersistenceException: org.hibernate.property.access.spi.PropertyAccessException: Error accessing field [private int ir.sadeghpro.breakfast.Product.id] by reflection for persistent property [ir.sadeghpro.breakfast.Product#id] : 1
    at org.hibernate.internal.ExceptionConverterImpl.convert(ExceptionConverterImpl.java:154)
    at org.hibernate.internal.ExceptionConverterImpl.convert(ExceptionConverterImpl.java:181)
    at org.hibernate.internal.ExceptionConverterImpl.convert(ExceptionConverterImpl.java:188)
    at org.hibernate.internal.SessionImpl.doFlush(SessionImpl.java:1460)
    at org.hibernate.internal.SessionImpl.managedFlush(SessionImpl.java:511)
    at org.hibernate.internal.SessionImpl.flushBeforeTransactionCompletion(SessionImpl.java:3283)
    at org.hibernate.internal.SessionImpl.beforeTransactionCompletion(SessionImpl.java:2479)
    at org.hibernate.engine.jdbc.internal.JdbcCoordinatorImpl.beforeTransactionCompletion(JdbcCoordinatorImpl.java:473)
    at org.hibernate.resource.transaction.backend.jdbc.internal.JdbcResourceLocalTransactionCoordinatorImpl.beforeCompletionCallback(JdbcResourceLocalTransactionCoordinatorImpl.java:178)
    at org.hibernate.resource.transaction.backend.jdbc.internal.JdbcResourceLocalTransactionCoordinatorImpl.access$300(JdbcResourceLocalTransactionCoordinatorImpl.java:39)
    at org.hibernate.resource.transaction.backend.jdbc.internal.JdbcResourceLocalTransactionCoordinatorImpl$TransactionDriverControlImpl.commit(JdbcResourceLocalTransactionCoordinatorImpl.java:271)
    at org.hibernate.engine.transaction.internal.TransactionImpl.commit(TransactionImpl.java:98)
    at ir.sadeghpro.breakfast.controller.Main.initialize(Main.java:110)
    at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:2548)
    ... 14 more
Caused by: org.hibernate.property.access.spi.PropertyAccessException: Error accessing field [private int ir.sadeghpro.breakfast.Product.id] by reflection for persistent property [ir.sadeghpro.breakfast.Product#id] : 1
    at org.hibernate.property.access.spi.GetterFieldImpl.get(GetterFieldImpl.java:75)
    at org.hibernate.tuple.entity.AbstractEntityTuplizer.getIdentifier(AbstractEntityTuplizer.java:224)
    at org.hibernate.persister.entity.AbstractEntityPersister.getIdentifier(AbstractEntityPersister.java:4931)
    at org.hibernate.persister.entity.AbstractEntityPersister.isTransient(AbstractEntityPersister.java:4631)
    at org.hibernate.engine.internal.ForeignKeys.isTransient(ForeignKeys.java:226)
    at org.hibernate.engine.internal.ForeignKeys.getEntityIdentifierIfNotUnsaved(ForeignKeys.java:276)
    at org.hibernate.type.EntityType.getIdentifier(EntityType.java:495)
    at org.hibernate.type.EntityType.nullSafeSet(EntityType.java:280)
    at org.hibernate.persister.collection.AbstractCollectionPersister.writeElement(AbstractCollectionPersister.java:911)
    at org.hibernate.persister.collection.AbstractCollectionPersister.recreate(AbstractCollectionPersister.java:1334)
    at org.hibernate.action.internal.CollectionRecreateAction.execute(CollectionRecreateAction.java:50)
    at org.hibernate.engine.spi.ActionQueue.executeActions(ActionQueue.java:604)
    at org.hibernate.engine.spi.ActionQueue.executeActions(ActionQueue.java:478)
    at org.hibernate.event.internal.AbstractFlushingEventListener.performExecutions(AbstractFlushingEventListener.java:356)
    at org.hibernate.event.internal.DefaultFlushEventListener.onFlush(DefaultFlushEventListener.java:39)
    at org.hibernate.internal.SessionImpl.doFlush(SessionImpl.java:1454)
    ... 24 more
Caused by: java.lang.IllegalArgumentException: Can not set int field ir.sadeghpro.breakfast.Product.id to java.lang.Integer
    at sun.reflect.UnsafeFieldAccessorImpl.throwSetIllegalArgumentException(UnsafeFieldAccessorImpl.java:167)
    at sun.reflect.UnsafeFieldAccessorImpl.throwSetIllegalArgumentException(UnsafeFieldAccessorImpl.java:171)
    at sun.reflect.UnsafeFieldAccessorImpl.ensureObj(UnsafeFieldAccessorImpl.java:58)
    at sun.reflect.UnsafeIntegerFieldAccessorImpl.getInt(UnsafeIntegerFieldAccessorImpl.java:56)
    at java.lang.reflect.Field.getInt(Field.java:574)
    at org.hibernate.property.access.spi.GetterFieldImpl.get(GetterFieldImpl.java:62)
    ... 39 more
Exception running application ir.sadeghpro.breakfast.Run

Answer 1

堆栈跟踪中打印的错误:

Caused by: java.lang.IllegalArgumentException: Can not set int field ir.sadeghpro.breakfast.Product.id to java.lang.Integer

您是否尝试过更改该字段？

您可以搜索similar errors也尝试那里的建议。