spring jpa使用联合主键

@Test
public void testAirlineRepository()
{
System.out.println(airlineRepository);

Airline al = new Airline();

al.setId(new AirlinePK("aa", "bb"));
al.setName("l2");

airlineRepository.save(al);

System.out.println(airlineRepository.findAll());
} 

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/**

 * file peter

2017年1月24日

 */

package org.peter.cat;

import java.io.Serializable;

import javax.persistence.Column;

import javax.persistence.Embeddable;

/**

 *file peter

2017年1月24日

 */

@Embeddable

public class AirlinePK implements Serializable{
@Column(length=3, nullable=false)
private String startCity;
@Column(length=3, nullable=false)
private String endCity;

public AirlinePK(){}

public AirlinePK(String startCity, String endCity) {
this.startCity = startCity;
this.endCity = endCity;
}

public String getStartCity() {
return startCity;
}
public void setStartCity(String startCity) {
this.startCity = startCity;
}
public String getEndCity() {
return endCity;
}
public void setEndCity(String endCity) {
this.endCity = endCity;
}
@Override
public int hashCode() {
final int prime = 31;
int result = 1;
result = prime * result + ((endCity == null) ? 0 : endCity.hashCode());
result = prime * result
+ ((startCity == null) ? 0 : startCity.hashCode());
return result;
}
@Override
public boolean equals(Object obj) {
if (this == obj)
return true;
if (obj == null)
return false;
if (getClass() != obj.getClass())
return false;
AirlinePK other = (AirlinePK) obj;
if (endCity == null) {
if (other.endCity != null)
return false;
} else if (!endCity.equals(other.endCity))
return false;
if (startCity == null) {
if (other.startCity != null)
return false;
} else if (!startCity.equals(other.startCity))
return false;
return true;
}
}

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/**

 * file peter

2017年1月24日

 */

package org.peter.cat;

import javax.persistence.Column;

import javax.persistence.EmbeddedId;

import javax.persistence.Entity;

/**

 *file peter

2017年1月24日

 */

@Entity

public class Airline {
@EmbeddedId
private AirlinePK id;
@Column(length=10, nullable=false)
private String name;

public Airline() {}

public Airline(String startCity, String endCity, String name) {
this.id = new AirlinePK(startCity, endCity);
this.name = name;
}

public AirlinePK getId() {
return id;
}
public void setId(AirlinePK id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}

}

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