小编Rac*_*hid的帖子

我是关于学习JPA,我想知道如何使用数据库自​​动增量向表实体管理器调用主键字段生成？我正在使用Mysql 5.5和Oracle Enterprise For Eclipse(OEFE)感谢您的帮助

如何从两个与@ManyToMany映射注释一起映射的entite中添加结果表中的其他列？

我有两个班:

package com.rachid.jpa;

import java.io.Serializable;
import java.lang.Integer;
import java.lang.String;
import java.util.Collection;
import java.sql.Date;
import javax.persistence.*;

/**
 * Entity implementation class for Entity: Project
 *
 */
@Entity
@Table(name="PROJECT")

public class Project implements Serializable {


@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
private Integer idProj;

private String projectName;
private Date startDate;
private Date endDate;

@ManyToMany(mappedBy="projects")
private Collection<Employee> employees;
private static final long serialVersionUID = 1L;

@OneToOne
@JoinColumn(name="matriculeChef")
private Employee chef;


public Project() {
    super();
}   
public Integer getIdProj() {
    return this.idProj;
}

public void …