hibernate-DetachedCriteria实现关联表条件复查

表结果如下

CREATE TABLE `ent_lable` (
  `idStr` char(32) NOT NULL,
  `pk_1` char(6) NOT NULL,
  `pk_2` char(32) NOT NULL,
  PRIMARY KEY (`idStr`)
) ENGINE=MyISAM DEFAULT CHARSET=utf8; 

 

本身为一张多对多的中间表

 

业务如下

　　要根据pk_1查询所有的pk_2,然后再根据所得的pk_2的值查询出相关连的pk_1

模型：

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

import org.hibernate.annotations.GenericGenerator;


@Entity
@Table(name="ent_lable")
public class EntLable  extends BaseModel{

    private static final long serialVersionUID = 1L;
    @Id
    @GeneratedValue(generator="paymentableGenerator")
    @GenericGenerator(name="paymentableGenerator",strategy="uuid")
    @Column(name="idStr")
    private String idStr;
    @Column(name="pk_1")
    private String pk_1;
    @Column(name="pk_2")
    private String pk_2;
    public void setIdStr(String idStr){
        this.idStr=idStr;
    }
    public String getIdStr(){
        return idStr;
    }
    public String getPk_1() {
        return pk_1;
    }
    public void setPk_1(String pk_1) {
        this.pk_1 = pk_1;
    }
    public String getPk_2() {
        return pk_2;
    }
    public void setPk_2(String pk_2) {
        this.pk_2 = pk_2;
    }
    
}

 

 

DetachedCriteria的处理逻辑

DetachedCriteria dc = DetachedCriteria.forClass(EntLable.class);
if(StringUtils.isBlank(pk_1)) return null;
dc.add(Restrictions.eq("pk_1", pk_1));
dc.setProjection(Projections.property("pk_2"));
DetachedCriteria dc1 = DetachedCriteria.forClass(EntLable.class);
dc1.add(Property.forName("pk_2").eq(dc));

 

 

 

 

另，父类

import org.springframework.util.StringUtils;


public abstract class BaseModel extends BaseObject implements Modelable {
    
    private static final long serialVersionUID = 1L;

    public int hashCode() {
        String idStr = getIdStr();
        return StringUtils.isEmpty(idStr)?super.hashCode():idStr.hashCode();
    }

    public boolean equals(Object other) {
        if (other == null) {
            return false;
        }
        if (other == this) {
            return true;
        }
        /*因为字节码增强的关系，getClass()不能用作判断的依据*/
        if (getClass().getPackage() != other.getClass().getPackage()) {
            return false;
        }
        if (hashCode() == other.hashCode()) {
            return true;
        }
        return false;
    }
}

 

import java.io.Serializable;

import org.apache.commons.lang.builder.ToStringBuilder;
import org.apache.commons.lang.builder.ToStringStyle;
import org.apache.log4j.Logger;

public class BaseObject implements Cloneable, Serializable {
    private static final long serialVersionUID = 1L;
    /**日志对象*/
    protected final Logger log = Logger.getLogger(getClass());
    /**覆盖toString方法，ToStringStyle取值为ToStringStyle.SHORT_PREFIX_STYLE
     * ，调试的时候注意会自动取所有引用的值，会触发所有的延迟加载
     * @return String
     * @see org.apache.commons.lang.builder.ToStringBuilder#reflectionToString(Object, ToStringStyle)
     */
    public String toString() {
        return ToStringBuilder.reflectionToString(this, ToStringStyle.SHORT_PREFIX_STYLE);
    }
    /**
     * 提供默认的clone方法的实现，不支持深层复制
     * @return Object
     */
    public Object clone() {
        try {
            return super.clone();
        } catch (CloneNotSupportedException ex) {
            throw new IllegalArgumentException(ex.getMessage());
        }
    }
}

import java.io.Serializable;


public interface Modelable extends JSONNotAware,Serializable, Cloneable {
    String getIdStr();
    void setIdStr(String idStr);
}

/**
 * 实现此接口的对象，都不会被ModelUtils中的model2JSON和modelList2JSONArray转换方法序列化
 */
public interface JSONNotAware {

}