JPA动态查询代码封装

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package com.platform.framework.dao.jpa;

import java.io.Serializable;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Date;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;

import javax.persistence.EntityManager;
import javax.persistence.criteria.CriteriaBuilder;
import javax.persistence.criteria.CriteriaBuilder.In;
import javax.persistence.criteria.CriteriaQuery;
import javax.persistence.criteria.Order;
import javax.persistence.criteria.Predicate;
import javax.persistence.criteria.Root;

import org.apache.log4j.Logger;

/**
 * Query基类

 * 
 * @describe：封装JPA CriteriaBuilder查询条件
 */
@SuppressWarnings({ "unused", "unchecked", "rawtypes", "null", "hiding" })
public class Query implements Serializable {

    private static final long serialVersionUID = 5064932771068929342L;

    private static Logger log = Logger.getLogger(Query.class);

    private EntityManager entityManager;

    /** 要查询的模型对象 */
    private Class clazz;

    /** 查询条件列表 */
    private Root from;

    private List predicates;

    private CriteriaQuery criteriaQuery;

    private CriteriaBuilder criteriaBuilder;

    /** 排序方式列表 */
    private List orders;

    /** 关联模式 */
    private Map subQuery;

    private Map linkQuery;

    private String projection;

    /** 或条件 */
    private List orQuery;

    private String groupBy;

    private Query() {
    }

    private Query(Class clazz, EntityManager entityManager) {
        this.clazz = clazz;
        this.entityManager = entityManager;
        this.criteriaBuilder = this.entityManager.getCriteriaBuilder();
        this.criteriaQuery = criteriaBuilder.createQuery(this.clazz);
        this.from = criteriaQuery.from(this.clazz);
        this.predicates = new ArrayList();
        this.orders = new ArrayList();
    }

    /** 通过类创建查询条件 */
    public static Query forClass(Class clazz, EntityManager entityManager) {
        return new Query(clazz, entityManager);
    }

    /** 增加子查询 */
    private void addSubQuery(String propertyName, Query query) {
        if (this.subQuery == null)
            this.subQuery = new HashMap();

        if (query.projection == null)
            throw new RuntimeException("子查询字段未设置");

        this.subQuery.put(propertyName, query);
    }

    private void addSubQuery(Query query) {
        addSubQuery(query.projection, query);
    }

    /** 增关联查询 */
    public void addLinkQuery(String propertyName, Query query) {
        if (this.linkQuery == null)
            this.linkQuery = new HashMap();

        this.linkQuery.put(propertyName, query);
    }

    /** 相等 */
    public void eq(String propertyName, Object value) {
        if (isNullOrEmpty(value))
            return;
        this.predicates.add(criteriaBuilder.equal(from.get(propertyName), value));
    }

    private boolean isNullOrEmpty(Object value) {
        if (value instanceof String) {
            return value == null || "".equals(value);
        }
        return value == null;
    }

    public void or(List propertyName, Object value) {
        if (isNullOrEmpty(value))
            return;
        if ((propertyName == null) || (propertyName.size() == 0))
            return;
        Predicate predicate = criteriaBuilder.or(criteriaBuilder.equal(from.get(propertyName.get(0)), value));
        for (int i = 1; i < propertyName.size(); ++i)
            predicate = criteriaBuilder.or(predicate, criteriaBuilder.equal(from.get(propertyName.get(i)), value));
        this.predicates.add(predicate);
    }

    public void orLike(List propertyName, String value) {
        if (isNullOrEmpty(value) || (propertyName.size() == 0))
            return;
        if (value.indexOf("%") < 0)
            value = "%" + value + "%";
        Predicate predicate = criteriaBuilder.or(criteriaBuilder.like(from.get(propertyName.get(0)), value.toString()));
        for (int i = 1; i < propertyName.size(); ++i)
            predicate = criteriaBuilder.or(predicate, criteriaBuilder.like(from.get(propertyName.get(i)), value));
        this.predicates.add(predicate);
    }

    /** 空 */
    public void isNull(String propertyName) {
        this.predicates.add(criteriaBuilder.isNull(from.get(propertyName)));
    }

    /** 非空 */
    public void isNotNull(String propertyName) {
        this.predicates.add(criteriaBuilder.isNotNull(from.get(propertyName)));
    }

    /** 不相等 */
    public void notEq(String propertyName, Object value) {
        if (isNullOrEmpty(value)) {
            return;
        }
        this.predicates.add(criteriaBuilder.notEqual(from.get(propertyName), value));
    }

    /**
     * not in
     * 
     * @param propertyName
     *            属性名称
     * @param value
     *            值集合
     */
    public void notIn(String propertyName, Collection value) {
        if ((value == null) || (value.size() == 0)) {
            return;
        }
        Iterator iterator = value.iterator();
        In in = criteriaBuilder.in(from.get(propertyName));
        while (iterator.hasNext()) {
            in.value(iterator.next());
        }
        this.predicates.add(criteriaBuilder.not(in));
    }

    /**
     * 模糊匹配
     * 
     * @param propertyName
     *            属性名称
     * @param value
     *            属性值
     */
    public void like(String propertyName, String value) {
        if (isNullOrEmpty(value))
            return;
        if (value.indexOf("%") < 0)
            value = "%" + value + "%";
        this.predicates.add(criteriaBuilder.like(from.get(propertyName), value));
    }

    /**
     * 时间区间查询
     * 
     * @param propertyName
     *            属性名称
     * @param lo
     *            属性起始值
     * @param go
     *            属性结束值
     */
    public void between(String propertyName, Date lo, Date go) {
        if (!isNullOrEmpty(lo) && !isNullOrEmpty(go)) {
            this.predicates.add(criteriaBuilder.between(from.get(propertyName), lo, go));
        }

        // if (!isNullOrEmpty(lo) && !isNullOrEmpty(go)) {
        // this.predicates.add(criteriaBuilder.lessThan(from.get(propertyName),
        // new DateTime(lo).toString()));
        // }
        // if (!isNullOrEmpty(go)) {
        // this.predicates.add(criteriaBuilder.greaterThan(from.get(propertyName),
        // new DateTime(go).toString()));
        // }

    }

    public void between(String propertyName, Number lo, Number go) {
        if (!(isNullOrEmpty(lo)))
            ge(propertyName, lo);

        if (!(isNullOrEmpty(go)))
            le(propertyName, go);
    }

    /**
     * 小于等于
     * 
     * @param propertyName
     *            属性名称
     * @param value
     *            属性值
     */
    public void le(String propertyName, Number value) {
        if (isNullOrEmpty(value)) {
            return;
        }
        this.predicates.add(criteriaBuilder.le(from.get(propertyName), value));
    }

    /**
     * 小于
     * 
     * @param propertyName
     *            属性名称
     * @param value
     *            属性值
     */
    public void lt(String propertyName, Number value) {
        if (isNullOrEmpty(value)) {
            return;
        }
        this.predicates.add(criteriaBuilder.lt(from.get(propertyName), value));
    }

    /**
     * 大于等于
     * 
     * @param propertyName
     *            属性名称
     * @param value
     *            属性值
     */
    public void ge(String propertyName, Number value) {
        if (isNullOrEmpty(value)) {
            return;
        }
        this.predicates.add(criteriaBuilder.ge(from.get(propertyName), value));
    }

    /**
     * 大于
     * 
     * @param propertyName
     *            属性名称
     * @param value
     *            属性值
     */
    public void gt(String propertyName, Number value) {
        if (isNullOrEmpty(value)) {
            return;
        }
        this.predicates.add(criteriaBuilder.gt(from.get(propertyName), value));
    }

    /**
     * in
     * 
     * @param propertyName
     *            属性名称
     * @param value
     *            值集合
     */
    public void in(String propertyName, Collection value) {
        if ((value == null) || (value.size() == 0)) {
            return;
        }
        Iterator iterator = value.iterator();
        In in = criteriaBuilder.in(from.get(propertyName));
        while (iterator.hasNext()) {
            in.value(iterator.next());
        }
        this.predicates.add(in);
    }

    /** 直接添加JPA内部的查询条件,用于应付一些复杂查询的情况,例如或 */
    public void addCriterions(Predicate predicate) {
        this.predicates.add(predicate);
    }

    /**
     * 创建查询条件
     * 
     * @return JPA离线查询
     */
    public CriteriaQuery newCriteriaQuery() {
        criteriaQuery.where(predicates.toArray(new Predicate[0]));
        if (!isNullOrEmpty(groupBy)) {
            criteriaQuery.groupBy(from.get(groupBy));
        }
        if (this.orders != null) {
            criteriaQuery.orderBy(orders);
        }
        addLinkCondition(this);
        return criteriaQuery;
    }

    private void addLinkCondition(Query query) {

        Map subQuery = query.linkQuery;
        if (subQuery == null)
            return;

        for (Iterator queryIterator = subQuery.keySet().iterator(); queryIterator.hasNext();) {
            String key = (String) queryIterator.next();
            Query sub = (Query) subQuery.get(key);
            from.join(key);
            criteriaQuery.where(sub.predicates.toArray(new Predicate[0]));
            addLinkCondition(sub);
        }
    }

    public void addOrder(String propertyName, String order) {
        if (order == null || propertyName == null)
            return;

        if (this.orders == null)
            this.orders = new ArrayList();

        if (order.equalsIgnoreCase("asc"))
            this.orders.add(criteriaBuilder.asc(from.get(propertyName)));
        else if (order.equalsIgnoreCase("desc"))
            this.orders.add(criteriaBuilder.desc(from.get(propertyName)));
    }

    public void setOrder(String propertyName, String order) {
        this.orders = null;
        addOrder(propertyName, order);
    }

    public Class getModleClass() {
        return this.clazz;
    }

    public String getProjection() {
        return this.projection;
    }

    public void setProjection(String projection) {
        this.projection = projection;
    }

    public Class getClazz() {
        return this.clazz;
    }

    public List getOrders() {
        return orders;
    }

    public void setOrders(List orders) {
        this.orders = orders;
    }

    public EntityManager getEntityManager() {
        return this.entityManager;
    }

    public void setEntityManager(EntityManager em) {
        this.entityManager = em;
    }

    public Root getFrom() {
        return from;
    }

    public List getPredicates() {
        return predicates;
    }

    public void setPredicates(List predicates) {
        this.predicates = predicates;
    }

    public CriteriaQuery getCriteriaQuery() {
        return criteriaQuery;
    }

    public CriteriaBuilder getCriteriaBuilder() {
        return criteriaBuilder;
    }

    public void setFetchModes(List fetchField, List fetchMode) {

    }

    public String getGroupBy() {
        return groupBy;
    }

    public void setGroupBy(String groupBy) {
        this.groupBy = groupBy;
    }

}

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import com.google.common.collect.Lists;
import com.platform.framework.dao.jpa.EntityManagerFactoryProxy;
import com.platform.framework.dao.jpa.IBaseDao;
import com.platform.framework.dao.jpa.Query;
/**
 * @describe 查询实例
 */
public class DemoServiceImpl extends EntityManagerFactoryProxy implements IDemoService {        
    private IBaseDao baseDao;

    public void setBaseDao(IBaseDao baseDao) {
        this.baseDao = baseDao;
    }
    /**
     * 城市列表
     * @param pid    String  城市父id
     * @param search String  检索（拼音、名称）
     * @param px     int     排序（3酒店数量4城市名称5拼音）
     * @return
     */
    public List getCity(String pid,String search,Integer px) {
        String propertyName = "pinyin";
        String order = "asc";
        Query query = Query.forClass(ZnCity.class, getEntityManager());
        if (!StringUtil.isBlank(pid) && "0".equals(pid)) {
            query.setGroupBy("pid");
        }else {
            query.eq("pid", pid);
        }
        List propertyNames = 
        Lists.newArrayList("CName","pinyin","suoxie");
        query.orLike(propertyNames, search);
        query.setOrder(propertyName, order);
        List znCitys = baseDao.query(query);
        return znCitys;
    }

}