问如何减少Hibernate类中重复的代码？

EN

package org.carl.recordkeeper.entity;

import java.io.Serializable;
import javax.persistence.Column;
import javax.persistence.Id;

public class BstRecordPK implements Serializable
{
// ------------------------------ FIELDS ------------------------------

private String bst;

private Integer instbit;

// --------------------- GETTER / SETTER METHODS ---------------------

@Id
@Column( name = "BST", nullable = false, length = 1 )
public String getBst()
{
    return bst;
}

public void setBst( String bst )
{
    this.bst = bst;
}

@Id
@Column( name = "INSTBIT", nullable = false )
public Integer getInstbit()
{
    return instbit;
}

public void setInstbit( Integer instbit )
{
    this.instbit = instbit;
}

// ------------------------ CANONICAL METHODS ------------------------

@Override
public boolean equals( Object o )
{
    if ( this == o )
    {
        return true;
    }
    if ( o == null || getClass() != o.getClass() )
    {
        return false;
    }

    BstRecordPK that = (BstRecordPK)o;

    if ( bst != null ? !bst.equals( that.bst ) : that.bst != null )
    {
        return false;
    }
    if ( instbit != null ? !instbit.equals( that.instbit ) : that.instbit != null )
    {
        return false;
    }

    return true;
}

@Override
public int hashCode()
{
    int result = instbit != null ? instbit.hashCode() : 0;
    result = 31 * result + ( bst != null ? bst.hashCode() : 0 );
    return result;
}
}