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  • Spring 多对对实体

    package com.wangshenghua.entity;
    
    import java.io.Serializable;
    import java.util.Set;
    
    import javax.persistence.CascadeType;
    import javax.persistence.Entity;
    import javax.persistence.GeneratedValue;
    import javax.persistence.GenerationType;
    import javax.persistence.Id;
    import javax.persistence.JoinColumn;
    import javax.persistence.JoinTable;
    import javax.persistence.ManyToMany;
    import javax.persistence.Table;
    
    @Entity
    @Table(name = "course")
    public class Course implements Serializable {
    
    	private static final long serialVersionUID = 5844590076435775458L;
    
    	@Id
    	@GeneratedValue(strategy = GenerationType.IDENTITY)
    	private int id;
    
    	private String name;

          /**
          * 一个学生对应多门功课<br>
          * 多对多时,使用中间表关联两者关系<br>
          */

    	@ManyToMany(cascade = CascadeType.ALL)
    	@JoinTable(name = "student_has_course", 
    	joinColumns = @JoinColumn(name = "course_id", 
    	referencedColumnName = "id"), 
    	inverseJoinColumns = @JoinColumn(name = "student_id", referencedColumnName = "id"))
    	private Set<Student> students;
    
    	// @JoinTable里的 name 中间表
    	// joinColumns 当前实体ID
    	// inverseJoinColumns对方实体ID
    
    	public Course() {
    	}
    
    	public Course(String name) {
    		super();
    		this.name = name;
    	}
    
    	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 Set<Student> getStudents() {
    		return students;
    	}
    
    	public void setStudents(Set<Student> students) {
    		this.students = students;
    	}
    
    	@Override
    	public String toString() {
    		return "Course [id=" + id + ", name=" + name + ", students=" + students + "]";
    	}
    
    }
    

      

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  • 原文地址:https://www.cnblogs.com/max-hou/p/11172952.html
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