hibernate 联合主键配置

一.可行demo: 联合主键， id自增

主键类可以把字段单独放一个类，实现Serializable接口，重写equals和hascode方法
自增：@GeneratedValue(strategy=GenerationType.AUTO)
表结构

DROP TABLE IF EXISTS `test`;
CREATE TABLE `test` (
  `id` bigint(19) NOT NULL AUTO_INCREMENT COMMENT '自增主键',
  `trigger_type` int(2) NOT NULL COMMENT '触发类型：10驶入山西、20驶出山西、30驶入西安、40驶出西安',
  `trigger_position` varchar(200) CHARACTER SET utf8 DEFAULT NULL COMMENT '触发位置',
  PRIMARY KEY (`id`, `trigger_type`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci COMMENT='test'
PARTITION BY LIST(trigger_type) (
    PARTITION shanxi VALUES IN (10, 20),
    PARTITION xian VALUES IN (30, 40)
);    

package com.entity;
import lombok.Data;

import javax.persistence.*;
/**
 * @ClassName FenceLockCarEntity
 * @author xxxx
 * @version 1.0.0
 * @Description test
 */
@Entity
@Table(name = "test")
@Data
public class TestEntity {

    @Id
    private TestKey testkey;
    @Id
    @Embedded
    @AttributeOverrides({
            @AttributeOverride(name = "id", column = @Column(name = "id")),
            @AttributeOverride(name = "triggerType", column = @Column(name = "trigger_type"))
    })
    public TestKey getTestkey() {
        return testkey;
    }

    public void setTestkey(TestKey testkey) {
        this.testkey = testkey;
    }
}    

package com.entity;
import javax.persistence.Column;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import java.io.Serializable;
public class TestKey implements Serializable {
    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    @Column(nullable = false, name = "id", columnDefinition = "bigint")
    private Long id;
    /**
     * 触发类型：10驶入山西、20驶出山西、30驶入西安、40驶出西安
     */
    @Id
    @Column(nullable = false, name = "trigger_type")
    private Integer triggerType;

    public Long getId() {
        return id;
    }
    public void setId(Long id) {
        this.id = id;
    }
    public Integer getTriggerType() {
        return triggerType;
    }
    public void setTriggerType(Integer triggerType) {
        this.triggerType = triggerType;
    }
    @Override
    public boolean equals(Object obj) {
        if (this == obj) {
            return true;
        }
        if (!(obj instanceof TestKey)) {
            return false;
        }
        TestKey key = (TestKey) obj;

        if (!this.id.equals(key.getId())) {
            return false;
        }
        if (!this.triggerType.equals(key.getTriggerType())) {
            return false;
        }
        return true;
    }
    @Override
    public int hashCode() {
        int result = 0;
        result = this.id == null ? 0 : this.id.hashCode();
        result = 29 * (this.triggerType == null ? 0 : this.triggerType.hashCode()) + result;
        return result;
    }
}

二.参考其他

Hibernate用注解配置复合主键有三种方式
①@Embeddable + @Id + @Embedded
②@Embeddable + @EmbeddedId
③@IdClass + @Id
解释：
@Embeddable 表示这个类可以嵌入到别的类中去，常以表示其他类的某个属性。
@Embedded 它和 @Embeddable 正好相反，它用来表示某个属性是被嵌入进来的。
@EmbeddedId = @Embedded + @Id
声明：
如果采用第三种方式，则必须为主键类写上默认构造方法，因为Hibernate是通过默认构造方法来实例化主键类的对象的。
首先，给出主键类的源代码：

package cn.saicent.model;
import java.io.Serializable;
import javax.persistence.Embeddable;
@Embeddable
public class CompositeKeyModelKey implements Serializable {
	private static final long serialVersionUID = 1717638966560959020L;
	private Integer kkey1;
	private Integer kkey2;
	public CompositeKeyModelKey(Integer kkey1, Integer kkey2) {
		this.kkey1 = kkey1;
		this.kkey2 = kkey2;
	}
	public Integer getkkey1() {
		return kkey1;
	}
	public void setkkey1(Integer kkey1) {
		this.kkey1 = kkey1;
	}
	public Integer getkkey2() {
		return kkey2;
	}
	public void setkkey2(Integer kkey2) {
		this.kkey2 = kkey2;
	}
	@Override
	public boolean equals(Object obj) {
		if(this == obj) {
			return true;
		}
		if(! (obj instanceof CompositeKeyModelKey)) {
			return false;
		}
		CompositeKeyModelKey key = (CompositeKeyModelKey)obj;
		if(!kkey1.equals(key.getkkey1())) {
			return false;
		}
		if(!kkey2.equals(key.getkkey2())) {
			return false;
		}
		return true;
	}
	@Override
	public int hashCode() {
		int result = 0;
		result = kkey1 == null ? 0 : kkey1.hashCode();
		result = 29 * (kkey2 == null ? 0 : kkey2.hashCode()) + result;
		return result;
	}
}

第一种方法（@Embeddable + @Id + @Embedded）的Pojo源代码如下：

package cn.saicent.model;
import javax.persistence.AttributeOverride;
import javax.persistence.AttributeOverrides;
import javax.persistence.Column;
import javax.persistence.Embedded;
import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.Table;
@Entity
@Table(name="COMPOSITE_KEY_TABLE")
public class CompositeKeyModel {
	private CompositeKeyModelKey compositeKeyModelKey;
	private String field;
	@Column(name = "FIELD")
	public String getField() {
		return field;
	}
	public void setField(String field) {
		this.field = field;
	}
	@Id
	@Embedded
	@AttributeOverrides({
		@AttributeOverride(name = "kkey1", column = @Column(name="KEY1")),
		@AttributeOverride(name = "kkey2", column = @Column(name="KEY2"))
	})
	public CompositeKeyModelKey getCompositeKeyModelKey() {
		return compositeKeyModelKey;
	}
	public void setCompositeKeyModelKey(CompositeKeyModelKey compositeKeyModelKey) {
		this.compositeKeyModelKey = compositeKeyModelKey;
	}
}

第二种方法（@Embeddable + @EmbeddedId）的Pojo源代码如下：

package cn.saicent.model;

import javax.persistence.AttributeOverride;
import javax.persistence.AttributeOverrides;
import javax.persistence.Column;
import javax.persistence.EmbeddedId;
import javax.persistence.Entity;
import javax.persistence.Table;

@Entity
@Table(name="COMPOSITE_KEY_TABLE")
public class CompositeKeyModel {
	private CompositeKeyModelKey compositeKeyModelKey;
	private String field;
	@Column(name = "FIELD")
	public String getField() {
		return field;
	}
	public void setField(String field) {
		this.field = field;
	}
	@EmbeddedId
	@AttributeOverrides({
		@AttributeOverride(name = "kkey1", column = @Column(name="KEY1")),
		@AttributeOverride(name = "kkey2", column = @Column(name="KEY2"))
	})
	public CompositeKeyModelKey getCompositeKeyModelKey() {
		return compositeKeyModelKey;
	}
	public void setCompositeKeyModelKey(CompositeKeyModelKey compositeKeyModelKey) {
		this.compositeKeyModelKey = compositeKeyModelKey;
	}
}

第三种方法（@IdClass + @Id）的Pojo类源代码如下：

package cn.saicent.model;

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.IdClass;
import javax.persistence.Table;

@Entity
@Table(name="COMPOSITE_KEY_TABLE")
@IdClass(CompositeKeyModelKey.class)
public class CompositeKeyModel {
	private Integer kkey1;
	private Integer kkey2;
	private String field;
	@Column(name = "FIELD")
	public String getField() {
		return field;
	}
	public void setField(String field) {
		this.field = field;
	}
	@Id
	@Column(name = "KEY1")
	public Integer getKkey1() {
		return kkey1;
	}
	public void setKkey1(Integer kkey1) {
		this.kkey1 = kkey1;
	}
	@Id
	@Column(name = "KEY2")
	public Integer getKkey2() {
		return kkey2;
	}
	public void setKkey2(Integer kkey2) {
		this.kkey2 = kkey2;
	}
}