这篇文章将为大家详细讲解有关java中JPA动态查询语句的用法，小编觉得挺实用的，因此分享给大家做个参考，希望大家阅读完这篇文章后可以有所收获。

成都创新互联专注于企业成都营销网站建设、网站重做改版、青羊网站定制设计、自适应品牌网站建设、H5开发、购物商城网站建设、集团公司官网建设、成都外贸网站建设、高端网站制作、响应式网页设计等建站业务，价格优惠性价比高，为青羊等各大城市提供网站开发制作服务。

我们现在在做一个OA系统，将新增的那些数据都写到数据库的时候是采用jpa规范的，（不太理解jpa的相关知识点，今天看下相关知识，然后再补充jpa的知识点），现在记录jpa中的动态查询语句，其实这些语句都是可以用sql语句写的，但是sql语句写得查询，删除，插入数据等操作不安全，所以采用jpa的语句。我们的项目是分为三层结构，第一层是实体层，在该层中专门定义某一实体的相关字段，它的set()，get()方法。第二层是服务层，将service和dao都放在一个组件中,在dao层中定义和数据库相关的操作方法，在service层中定义相关的业务逻辑层要调用的方法。第三层是restful层，在这层定义的是和前端交互的组件。

首先讲讲第一层：实体层

定义一个实体

/**
* 邮件实体
*
*/  
@Entity  
@Table(name = "mail_tbl")  
public class InnerMails implements Serializable {  

	private static final long serialVersionUID = 4999674279957375152L;  

	@Id  
	@GeneratedValue  
	private long id;  

	private String subject;// 主题  

	private String toMails;// 收件人 格式 ：姓名;姓名  

	private String urgency;// 紧急程度  
	  
	@Column(name = "sendDate")  
	@Temporal(TemporalType.TIMESTAMP)  
	private Date sendDate;// 发布日期  

	private String content;// 邮件内容  

	// 原文附件  
	@OneToMany(cascade={ CascadeType.MERGE,CascadeType.REMOVE})  
	@JoinColumn(name = "mail_id")  
	@OrderBy(value = "id DESC")//注释指明加载Attachment时按id的降序排序	
	private Set appendFiles=new HashSet();// 附件  

	private String mailUser;// 邮件拥有者 格式：userId  

	private String sendMail;// 邮件发送者 格式：姓名  

	private int type;// 状态标示：-1删除；0草稿；1发送；2未读收件，3已读收件  

	public long getId() {  
		return id;  
	}  

	public void setId(long id) {  
		this.id = id;  
	}  

	public String getSubject() {  
		return subject;  
	}  

	public void setSubject(String subject) {  
		this.subject = subject;  
	}  

	public String getToMails() {  
		return toMails;  
	}  

	public void setToMails(String toMails) {  
		this.toMails = toMails;  
	}  

	public String getUrgency() {  
		return urgency;  
	}  

	public void setUrgency(String urgency) {  
		this.urgency = urgency;  
	}  

	public Date getSendDate() {  
		return sendDate;  
	}  

	public void setSendDate(Date sendDate) {  
		this.sendDate = sendDate;  
	}  

	public String getContent() {  
		return content;  
	}  

	public void setContent(String content) {  
		this.content = content;  
	}  
	public String getMailUser() {  
		return mailUser;  
	}  

	  
	public void setMailUser(String mailUser) {  
		this.mailUser = mailUser;  
	}  

	public Set getAppendFiles() {  
		return appendFiles;  
	}  

	public void setAppendFiles(Set appendFiles) {  
		this.appendFiles = appendFiles;  
	}  

	public String getSendMail() {  
		return sendMail;  
	}  

	public void setSendMail(String sendMail) {  
		this.sendMail = sendMail;  
	}  

	public int getType() {  
		return type;  
	}  

	public void setType(int type) {  
		this.type = type;  
	}  

}

定义查询实体：

package com.gzydt.oa.commons;  

import java.util.ArrayList;  
import java.util.HashMap;  
import java.util.List;  
import java.util.Map;  

/**
* 分页查询参数
*  
* @author huangzhenwei
* @since 2014-11-21
*  
*/  
public class QueryParam {  

	// 排序字段，以“+”、“-”符号连接排序字段名：“+key”表示 按“key”字段升序，“-key”表示按“key”字段降序。  
	private List sorts = new ArrayList();  
	// 起始记录下标，从0开始计算  
	private int first = 0;  
	// 每页最大记录数  
	private int max = 10;  
	// 是否分页标志  
	private boolean isPage = true;  

	// 查询参数  
	private Map param = new HashMap();  

	public QueryParam() {  

	}  

	public int getFirst() {  
		return first;  
	}  

	public void setFirst(int first) {  
		this.first = first;  
	}  

	public int getMax() {  
		return max;  
	}  

	public void setMax(int max) {  
		this.max = max;  
	}  

	public Map getParam() {  
		return param;  
	}  

	public void setParam(Map param) {  
		this.param = param;  
	}  

	public boolean isPage() {  
		return isPage;  
	}  

	public void setPage(boolean isPage) {  
		this.isPage = isPage;  
	}  

	public List getSorts() {  
		return sorts;  
	}  

	public void setSorts(List sorts) {  
		this.sorts = sorts;  
	}  
}

第二层：服务层
dao层：定义和数据库相关操作的方法

package com.gzydt.oa.dao;  
  
import java.util.List;  
  
import com.gzydt.oa.commons.QueryParam;  
import com.gzydt.oa.entity.AppendFile;  
import com.gzydt.oa.entity.InnerMails;  
  
/**
* 邮件发送dao接口
*
*/  
public interface InnerMailDao {  
	/**
	 * 保存邮件
	 * @param mail
	 * @return
	 */  
	public InnerMails save(InnerMails mail);  
	/**
	 * 更新邮件
	 * @param mail
	 * @return
	 */  
	public InnerMails update(InnerMails mail);  
	/**
	 * 删除邮件
	 * @param id
	 */  
	public void delete(long id);  
	/**
	 * 查询邮件
	 * @param queryParam
	 * @return
	 */  
	public List getlist(QueryParam queryParam);  
	/**
	 * 获取单个邮件
	 * @param id
	 * @return
	 */  
	public InnerMails get(long id);  
	/**
	 * 获取满足条件的邮件的总数
	 * @param queryParam
	 * @return
	 */  
	public int getCount(QueryParam queryParam);  
   /**
	* 新增附件
	* @param id
	* @param appendFile
	*/  
	public void addAttach(long id,AppendFile appendFile);  
}

package com.gzydt.oa.dao.impl;  
  
import java.text.DateFormat;  
import java.text.SimpleDateFormat;  
import java.util.ArrayList;  
import java.util.Date;  
import java.util.HashSet;  
import java.util.Iterator;  
import java.util.List;  
import java.util.Map;  
import java.util.Set;  
  
import javax.persistence.EntityManager;  
import javax.persistence.TypedQuery;  
import javax.persistence.criteria.CriteriaBuilder;  
import javax.persistence.criteria.CriteriaQuery;  
import javax.persistence.criteria.Predicate;  
import javax.persistence.criteria.Root;  
  
import com.gzydt.oa.commons.QueryParam;  
import com.gzydt.oa.dao.InnerMailDao;  
import com.gzydt.oa.entity.AppendFile;  
import com.gzydt.oa.entity.InnerMails;  
  
/**
* 邮件实现类
*/  
public class InnerMailDaoImpl implements InnerMailDao{  
  
	private EntityManager entityManager;  
	public void setEntityManager(EntityManager entityManager) {  
		this.entityManager = entityManager;  
	}  
	/**
	 * 保存邮件
	 * @param mail
	 * @return
	 */  
	@Override  
	public InnerMails save(InnerMails mail) {  
		try {  
			entityManager.persist(mail);  
			entityManager.flush();  
			return mail;  
		} catch ( Exception e ) {  
			e.printStackTrace();  
			return null;  
		}  
	}  
	/**
	 * 更新邮件
	 * @param mail
	 * @return
	 */  
	@Override  
	public InnerMails update(InnerMails mail) {  
		try {  
			entityManager.merge(mail);  
			return mail;  
		} catch ( Exception e ) {  
			e.printStackTrace();  
			return null;  
		}  
	}  
	/**
	 * 删除邮件
	 * @param id
	 */  
	@Override  
	public void delete(long id) {  
		  
			entityManager.createQuery("delete from  PhoneRecord e where e.id=:id").setParameter("id", id).executeUpdate();  
			
		  
	}  
	/**
	 * 查询邮件
	 * @param queryParam
	 * @return
	 */  
	@Override  
	public List getlist(QueryParam queryParam) {  
		CriteriaBuilder cb = entityManager.getCriteriaBuilder();  
		CriteriaQuery criteriaQuery = cb.createQuery(InnerMails.class);  
		Root register = criteriaQuery.from(InnerMails.class);  
		// 过滤条件  
		Predicate[] predicates = createPredicate(queryParam, cb, register);  
		criteriaQuery.where(predicates);  
		int start = queryParam.getFirst();  
		int end = queryParam.getMax();  
		TypedQuery typedQuery = entityManager.createQuery(criteriaQuery);  
		typedQuery.setFirstResult(start).setMaxResults(end);  
		return typedQuery.getResultList();  
	}  
  //设置查询条件  
	private Predicate[] createPredicate(QueryParam queryParam, CriteriaBuilder cb, Root entity) {  
		List predicates=new ArrayList();  
		//取出查询条件  
		Map param= queryParam.getParam();  
		for(Map.Entry entry:param.entrySet()){  
			String key=entry.getKey().toString();  
			String value=entry.getValue().toString();  
			if(key.equals("sendDate")){  
			   Predicate conditionTime = createOperateTime(key,cb,value,entity);  
			   if(null!=conditionTime){  
				   predicates.add(conditionTime);  
			   }		
			}else{  
				predicates.add(cb.like(entity. get(key),"%"+value+"%"));  
			}  
		}  
		return predicates.toArray(new Predicate[0]);  
	}  
  
	/**
	 * 将时间作为查询条件的方法
	 * @param cb
	 * @param value
	 * @param entity
	 */  
	private Predicate createOperateTime(String key,CriteriaBuilder cb, String value, Root entity) {	
		if(null == value){  
			return null;  
		}  
		String[] operateTime=value.split("~");  
		if(operateTime.length!=2){  
			return null;  
		}  
		try {  
			DateFormat df=new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");//格式一定要写正确，  
			Date t1=df.parse(operateTime[0] + " 00:00:00");  
			Date t2=df.parse(operateTime[1] + " 23:59:59");  
			return cb.between(entity. get(key), t1, t2);  
		} catch ( Exception e ) {  
		   e.printStackTrace();  
		}  
		return null;  
		  
	}  
  
	/**
	 * 获取单个邮件
	 * @param id
	 * @return
	 */  
	@Override  
	public InnerMails get(long id) {  
		InnerMails innersMails=entityManager.find(InnerMails.class, id);  
	   Iterator iterator=innersMails.getAppendFiles().iterator();  
		Set attachs=new HashSet();  
		while(iterator.hasNext()){  
			AppendFile appendFile=new AppendFile();  
			appendFile=iterator.next();  
			attachs.add(appendFile);	
		}  
		innersMails.setAppendFiles(attachs);  
	   return innersMails;  
	}  
	/**
	 * 获取满足条件的邮件的总数
	 * @param queryParam
	 * @return
	 */  
	@Override  
	public int getCount(QueryParam queryParam) {  
		CriteriaBuilder cb = entityManager.getCriteriaBuilder();  
		CriteriaQuery criteriaQuery = cb.createQuery(Long.class);  
		Root mails = criteriaQuery.from(InnerMails.class);  
		criteriaQuery.select(cb.countDistinct(mails));  
		// 过滤条件  
		Predicate[] predeicates = createPredicate(queryParam, cb, mails);  
		criteriaQuery.where(predeicates);  
		TypedQuery typedQuery = entityManager.createQuery(criteriaQuery);  
		int count = 0;  
		try {  
			count = typedQuery.getSingleResult().intValue();  
		} catch ( Exception e ) {  
			e.printStackTrace();  
		}  
		return count;  
	}  
	/**
	 * 新增附件
	 * @param id
	 * @param appendFile
	 */  
	@Override  
	public void addAttach(long id, AppendFile appendFile) {  
		InnerMails entity=this.get(id);  
		entity.getAppendFiles().add(appendFile);  
		entityManager.merge(entity);  
		  
	}  
  
}

动态查询语句的相关知识

1：查询User表中的字段adminlever的小于给定值的数据

第一种写法：（安全，推荐使用这种）

/**
	* 查询某一级别以上的用户
	*/  
   @Override  
   public List getOnLeverUper(int lever) {  
	 CriteriaBuilder cb =entityManager.getCriteriaBuilder();  
	 CriteriaQuery criterQuery=cb.createQuery(User.class);  
	 Root entity=criterQuery.from(User.class);  
	 Path adminLever=entity. get("adminlever") ;  
	 criterQuery.where(cb.lessThan(adminLever, lever));  
	 TypedQuery typedQuery=entityManager.createQuery(criterQuery);  
	 return typedQuery.getResultList();  
	
   }

第二种写法：(不太安全，)

/**
	* 查询某一级别以上的用户
	*/  
   @Override  
   public List getOnLeverUper(int lever) {  
	   List users=entityManager.createQuery("from User u where u.adminlever<:adminlever")  
			   .setParameter("adminlever",lever).getResultList();  
		return users;	
	
   }

第二种删除数据（有时候会由于某实体和另一实体设置了一对一或者多对一，或者多对多的关系而导致不能正常删除数据），解决方法：

/**
	 * 删除登记信息
	 *  
	 * @param id
	 *			登记编号
	 */  
	@Override  
	public void handleDelete(long id) throws Exception {  
		ReceiptEntity entity = entityManager.find(ReceiptEntity.class, id);  
		entityManager.remove(entity);  
		//下面的的方法删除应为存在外键关联会删除失败  
	   /*entityManager.createQuery("delete from  ReceiptEntity e where e.id=:id").
		setParameter("id", id).executeUpdate();*/  
	}

service层：接口

package com.gzydt.oa.service;  
  
import java.util.List;  
  
import com.gzydt.oa.commons.QueryParam;  
import com.gzydt.oa.entity.AppendFile;  
import com.gzydt.oa.entity.InnerMails;  
  
/**
* 内部邮件接口
*
*/  
public interface InnerMailService {  
	/**
	 * 保存邮件
	 * @param mail
	 * @return
	 */  
	public InnerMails save(InnerMails mail);  
	/**
	 * 更新邮件
	 * @param mail
	 * @return
	 */  
	public InnerMails update(InnerMails mail);  
	/**
	 * 删除邮件
	 * @param id
	 */  
	public void delete(long id);  
	/**
	 * 查询邮件
	 * @param queryParam
	 * @return
	 */  
	public List getlist(QueryParam queryParam);  
	/**
	 * 获取单个邮件
	 * @param id
	 * @return
	 */  
	public InnerMails get(long id);  
	/**
	 * 获取满足条件的邮件的总数
	 * @param queryParam
	 * @return
	 */  
	public int getCount(QueryParam queryParam);  
	/**
	 * 发邮件
	 * @param content
	 *//*
	public void sendMail(String content);*/  
	/**
	 * 新增附件
	 * @param id
	 * @param appendFile
	 */  
	public void addAttach(long id,AppendFile appendFile);  
  
}

service层:实现类

package com.gzydt.oa.service.impl;  
  
import java.util.List;  
  
import com.gzydt.oa.commons.QueryParam;  
import com.gzydt.oa.dao.InnerMailDao;  
import com.gzydt.oa.entity.AppendFile;  
import com.gzydt.oa.entity.InnerMails;  
import com.gzydt.oa.service.InnerMailService;  
  
/**
* 内部邮件服务类
*
*/  
public class InnerMailServiceImpl implements InnerMailService{  
  
	private InnerMailDao mailDao;  
	  
	public void setMailDao(InnerMailDao mailDao) {  
		this.mailDao = mailDao;  
	}  
	/**
	 * 保存邮件
	 * @param mail
	 * @return
	 */  
	@Override  
	public InnerMails save(InnerMails mail) {  
		return mailDao.save(mail);  
	}  
  
	@Override  
	public InnerMails update(InnerMails mail) {  
		return mailDao.update(mail);  
	}  
	/**
	 * 删除邮件
	 * @param id
	 */  
	@Override  
	public void delete(long id) {  
	   mailDao.delete(id);  
		  
	}  
	/**
	 * 查询邮件
	 * @param queryParam
	 * @return
	 */  
	@Override  
	public List getlist(QueryParam queryParam) {  
	   return mailDao.getlist(queryParam);  
	}  
	/**
	 * 获取单个邮件
	 * @param id
	 * @return
	 */  
	@Override  
	public InnerMails get(long id) {  
	   return mailDao.get(id);  
	}  
	/**
	 * 获取满足条件的邮件的总数
	 * @param queryParam
	 * @return
	 */  
	@Override  
	public int getCount(QueryParam queryParam) {  
		return mailDao.getCount(queryParam);  
	}  
  
   /* @Override
	public void sendMail(String content) {
		
		
	}*/  
	/**
	 * 新增附件
	 * @param id
	 * @param appendFile
	 */  
	@Override  
	public void addAttach(long id, AppendFile appendFile) {  
	   mailDao.addAttach(id, appendFile);  
		  
	}  
  
}

在服务层中定义相关的服务配置

第三层：restful层

package com.gzydt.oa.resource;  
  
import java.text.ParseException;  
import java.util.List;  
  
import javax.ws.rs.Consumes;  
import javax.ws.rs.DELETE;  
import javax.ws.rs.GET;  
import javax.ws.rs.HeaderParam;  
import javax.ws.rs.POST;  
import javax.ws.rs.PUT;  
import javax.ws.rs.Path;  
import javax.ws.rs.PathParam;  
import javax.ws.rs.Produces;  
import javax.ws.rs.QueryParam;  
import javax.ws.rs.core.MediaType;  
import javax.ws.rs.core.Response;  
  
import org.apache.cxf.jaxrs.ext.multipart.Attachment;  
import org.apache.cxf.jaxrs.ext.multipart.Multipart;  
  
/**
* 内部邮件的restful
*/  
@Path("/mails")  
public interface InnerMailsResource {  
	/**
	 * 新增邮件
	 * @param content
	 * @return
	 */  
	@POST  
	@Path("/")  
	@Consumes("multipart/form-data")  
	public Response save(@Multipart("content") String content,  
List attachments) throws ParseException ;  
	/**
	 * 更新邮件
	 * @param id
	 * @param content
	 * @return
	 */  
	@PUT  
	@Path("/{id}")  
	@Consumes("multipart/form-data")  
	public Response update(@PathParam("id") long id,@Multipart("content") String content,  
List attachments) throws ParseException;  
	/**
	 * 查询邮件
	 * @param id
	 * @return
	 */  
	@GET  
	@Path("/{id}")  
	public Response get(@PathParam("id") long id);  
	/**
	 * 查询邮件列表
	 * @param range
	 * @param query
	 * @return
	 */  
	@GET  
	@Path("/list")  
	public Response getList(@HeaderParam("range") String range,@QueryParam("query") String query);  
	/**
	 * 删除邮件
	 * @param id
	 * @return
	 */  
	@DELETE  
	@Path("/{id}")  
	public Response delete(@PathParam("id") long id);  
	/**
	 * 发送邮件
	 * @param content
	 * @return  数据格式：{"data":{},"toMail":""}
	 */  
	@POST  
	@Path("/sendMails/{id}")  
	public Response sendMail(@PathParam("id")long id) ;  
	/**
	 * 下载附件
	 * @param id(附件的id)
	 * @return
	 */  
	@GET  
	@Path("/getAttach/{id}")  
	@Produces(MediaType.APPLICATION_OCTET_STREAM)  
	public Response downLoadAttach(@PathParam("id") long id);  
	  
	  
  
}

实现类：

package com.gzydt.oa.resource.impl;  
  
import java.io.File;  
import java.io.FileInputStream;  
import java.io.FileOutputStream;  
import java.io.IOException;  
import java.io.InputStream;  
import java.io.OutputStream;  
import java.text.ParseException;  
import java.text.SimpleDateFormat;  
import java.util.Date;  
import java.util.HashSet;  
import java.util.List;  
import java.util.Set;  
import java.util.regex.Matcher;  
import java.util.regex.Pattern;  
  
import javax.activation.DataHandler;  
import javax.ws.rs.WebApplicationException;  
import javax.ws.rs.core.MediaType;  
import javax.ws.rs.core.Response;  
import javax.ws.rs.core.Response.Status;  
import javax.ws.rs.core.StreamingOutput;  
  
import net.sf.json.JSONArray;  
import net.sf.json.JSONObject;  
import net.sf.json.JsonConfig;  
  
import org.apache.cxf.jaxrs.ext.multipart.Attachment;  
/*import org.json.JSONArray;*/  
  
import com.gzydt.oa.commons.QueryParam;  
import com.gzydt.oa.entity.AppendFile;  
import com.gzydt.oa.entity.InnerMails;  
import com.gzydt.oa.resource.InnerMailsResource;  
import com.gzydt.oa.service.AppendFileService;  
import com.gzydt.oa.service.InnerMailService;  
import com.gzydt.oa.util.Constant;  
import com.gzydt.oa.util.QueryUtil;  
  
public class InnerMailsResourceImpl implements InnerMailsResource {  
	private InnerMailService emailService;  
  
	public void setEmailService(InnerMailService emailService) {  
		this.emailService = emailService;  
	}  
  
	private AppendFileService appendFileService;  
  
	public void setAppendFileService(AppendFileService appendFileService) {  
		this.appendFileService = appendFileService;  
	}  
  
	private static final String PATH = "data/oa/upload/mails";  
  
	@Override  
	public Response save(String content, List attachments) throws ParseException {  
		//去掉懒加载字段  
		JsonConfig jsonConfig = Constant.jsonDateConfig;  
		jsonConfig.setExcludes(new String[] { "appendFiles"});  
		JSONObject preceInfo = JSONObject.fromObject(content);  
		JSONObject backInfo = new JSONObject();  
		InnerMails entity = new InnerMails();  
		Date sendDate = null;  
		if ( preceInfo.optString("sendDate") != null && preceInfo.optString("sendDate") != "" ) {  
		//这里的MM必须是要大写，若是写为mm,则是分钟，，格式一定要按照正规的来写yyyy-MM-dd HH:mm:ss，  
//该大写就大写，小写就小写，并且中间有空格等，都不能错误。不然时间会出错  
		SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd");  
			sendDate = df.parse(preceInfo.optString("sendDate"));  
		}  
		preceInfo.put("sendDate", sendDate);  
		entity = (InnerMails) JSONObject.toBean(preceInfo, InnerMails.class);  
		
		if ( !preceInfo.has("type") ) {  
			entity.setType(0);  
		}  
		entity = emailService.save(entity);  
	 // 新增附件到附件表中  
		Set appfiles=addAttach(attachments, entity);  
		entity.setAppendFiles(appfiles);  
		entity=emailService.update(entity);  
  
		if ( null != entity ) {  
			backInfo = JSONObject.fromObject(entity);  
			return Response.ok(backInfo.toString(), MediaType.APPLICATION_JSON).build();  
		}  
		backInfo.put("message", "保存失败");  
		return Response.ok(backInfo.toString(), MediaType.APPLICATION_JSON).build();  
  
	}  
	  
	// 保存并关联附件  
	private  Set  addAttach(List attachments,InnerMails entity){  
		Set appenFiles=new HashSet();  
		for (Attachment attachment : attachments) {  
			if (attachment.getContentType().toString().startsWith("application/octet-stream")) {  
				DataHandler dh = attachment.getDataHandler();  
				long time = new Date().getTime();  
				String fileName = null;  
				try {  
					fileName = new String(dh.getName().getBytes("ISO-8859-1"), "UTF-8");  
					writeFile(dh, fileName);  
				} catch (Exception e) {  
					e.printStackTrace();  
					
				}  
				AppendFile file = new AppendFile();  
				file.setSerialNumber(time);// 唯一标识  
				file.setFileName(fileName);// 文件名  
				file.setExtension(fileName.substring(fileName.lastIndexOf(".") + 1));// 文件后缀	
				file.setType("email");// 文件类型  
				emailService.addAttach(entity.getId(), file);  
				AppendFile result = null;  
				result = appendFileService.getByNumber(time);  
				appenFiles.add(result);  
				  
			}  
		}  
		return appenFiles;  
	}  
	
  
	// 写文件  
	private void writeFile(DataHandler dh, String fileName) throws IOException {  
		InputStream is = dh.getInputStream();  
		File file = new File(PATH);  
		if ( !file.exists() ) {  
			file.mkdirs();  
		}  
		// LOG.info("附件目录：" + file.getAbsolutePath());  
		writeToFile(is, PATH + fileName);  
	}  
  
	private void writeToFile(InputStream is, String path) throws IOException {  
  
		File file = new File(path);  
		OutputStream out = new FileOutputStream(file);  
		int len = 0;  
		byte[] bytes = new byte[1024];  
		while ( (len = is.read(bytes)) != -1 ) {  
			out.write(bytes, 0, len);  
		}  
		out.flush();  
		out.close();  
  
	}  
  
	@Override  
	public Response update(long id, String content, List attachments) throws ParseException {  
		InnerMails entity = emailService.get(id);  
		JSONObject preceInfo = JSONObject.fromObject(content);  
		JSONObject backInfo = new JSONObject();  
		if ( null != entity ) {  
			entity.setSubject(preceInfo.optString("subject"));  
			entity.setToMails(preceInfo.optString("toMails"));  
			entity.setUrgency(preceInfo.optString("urgency"));  
			Date sendDate = null;  
			if ( preceInfo.optString("sendDate") != null && preceInfo.optString("sendDate") != "" ) {  
				SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd");  
				sendDate = df.parse(preceInfo.optString("sendDate"));  
			}  
		  //保存附件  
			Set appfiles=addAttach(attachments, entity);  
			entity.setAppendFiles(appfiles);  
			entity.setSendDate(sendDate);  
			entity.setContent(preceInfo.optString("content"));  
			entity.setMailUser(preceInfo.optString("mailUser"));  
			entity.setSendMail(preceInfo.optString("sendMail"));  
			entity.setType(preceInfo.optInt("type"));  
			
			addAttach(attachments, entity);  
			entity = emailService.update(entity);  
			if ( entity != null ) {  
				backInfo = JSONObject.fromObject(entity);  
				return Response.ok(backInfo.toString(), MediaType.APPLICATION_JSON).build();  
			} else {  
				backInfo.put("message", "修改失败");  
				return Response.ok(backInfo.toString(), MediaType.APPLICATION_JSON).build();  
			}  
  
		}  
		backInfo.put("message", "没有找到指定的邮件");  
		return Response.ok(backInfo.toString(), MediaType.APPLICATION_JSON).build();  
	}  
  
	@Override  
	public Response get(long id) {  
		JSONObject backInfo = new JSONObject();  
		InnerMails entity = emailService.get(id);  
		JSONObject jo;  
		/*JsonConfig JSONConfig = Constant.jsonDateConfigWithHour;
		JSONConfig.setExcludes(new String[] {"appendFiles"});*/  
		// 去掉延迟加载的字段  
		jo = JSONObject.fromObject(entity);  
		//修改状态为已读  
		entity.setType(3);  
		emailService.update(entity);  
		if ( null != entity ) {  
			backInfo = JSONObject.fromObject(jo);  
			return Response.ok(backInfo.toString(), MediaType.APPLICATION_JSON).build();  
		}  
		backInfo.put("message", "没有找到指定的内部邮件");  
		return Response.ok(backInfo.toString(), MediaType.APPLICATION_JSON).build();  
	}  
  
	@Override  
	public Response getList(String range, String query) {  
		QueryParam queryParam = new QueryParam();  
		int from = 0;  
		int to = 9;  
		try {  
			
			String[] ranges = range.replace("items=",  "").split("-");  
			from = Integer.parseInt(ranges[0]);  
			to = Integer.parseInt(ranges[1]);  
		} catch ( Exception e ) {  
			e.printStackTrace();  
		}  
  
		queryParam.setFirst(from);  
		int max = to - from + 1;  
		if ( max > 0 ) {  
			queryParam.setMax(max);  
		}  
		if(null!=query){  
			QueryUtil.prepareQuery(query, queryParam);  
		}  
		int count=emailService.getCount(queryParam);  
		List list=emailService.getlist(queryParam);  
	   JsonConfig jsonconfig=Constant.jsonDateConfig;  
		jsonconfig.setExcludes(new String[] {"appendFiles"});  
		String contentRange=String.format("items %d-%d/%d", from,to,count);  
		JSONArray ja = JSONArray.fromObject(list,jsonconfig);  
		String entity = ja.toString();  
		return Response.ok(entity, MediaType.APPLICATION_JSON).header("Content-Range", contentRange).build();  
  
	}  
  
	@Override  
	public Response delete(long id) {  
	   JSONObject backInfo=new JSONObject();  
	   try {  
		emailService.delete(id);  
		backInfo.put("message", "删除成功");  
		return Response.ok(backInfo.toString(), MediaType.APPLICATION_JSON).build();  
	} catch ( Exception e ) {  
		backInfo.put("message","删除失败");  
		return Response.ok(backInfo.toString(),MediaType.APPLICATION_JSON).build();  
	}  
	}  
  
	@Override  
	public Response sendMail(/*String content,List attachments*/long id){  
	   JSONObject backInfo=new JSONObject();  
		//通过id找到对应的邮件  
		InnerMails entity=emailService.get(id);  
		//将A的邮件mail状态改为发送  
		entity.setType(1);  
		entity=emailService.update(entity);  
		//找到收件人，根据收件人的个数来新增多条邮件  
		String toMail=entity.getToMails();  
		String[] toMails=toMail.split(",");  
		  
		for(String tomail:toMails){  
			//新增邮件，修改mail1的拥有者，修改状态为未读  
			InnerMails newMails=new InnerMails();  
			newMails.setSubject(entity.getSubject());  
			newMails.setToMails(entity.getToMails());  
			newMails.setUrgency(entity.getUrgency());  
			newMails.setAppendFiles(entity.getAppendFiles());  
			newMails.setSendDate(entity.getSendDate());  
			newMails.setContent(entity.getContent());  
			newMails.setSendMail(entity.getSendMail());  
			newMails.setType(2);  
			newMails.setMailUser(getNoFromChar(tomail));  
			emailService.save(newMails);  
		}  
		  
		backInfo.put("发送邮件的人数", toMails.length);  
		return Response.ok(backInfo.toString(), MediaType.APPLICATION_JSON).build();  
		  
		  
	}  
	//截取字符串中的数字  
	 private String  getNoFromChar(String params) {  
		String regex="[^0-9]";  
		Pattern p=Pattern.compile(regex);  
		Matcher m=p.matcher(params);  
		return m.replaceAll("").trim();  
	}  
  
	@Override  
	public Response downLoadAttach(long id) {  
	   //根据附件名称去指定路径中找附件  
		AppendFile appendFile=appendFileService.get(id);  
		if ( null == appendFile ) {  
			return Response.status(Status.NOT_FOUND).entity("找不到文件").build();  
		}  
		final File file=new File(PATH, appendFile.getFileName());  
		JSONObject preceInfo=new JSONObject();  
		if(!file.exists()||!file.isFile()){  
			preceInfo.put("message","没有找到指定的文件");  
			return Response.status(Status.NOT_FOUND).entity("找不到文件："+file.getName()).build();  
		}  
		//下载附件  
		StreamingOutput entity=downLoad(file);  
		String fileName=file.getName().toLowerCase();  
		String type=MediaType.APPLICATION_OCTET_STREAM;  
		if(fileName.endsWith(".jpg")||fileName.endsWith(".png")){  
			type="image/jpeg";  
		}else if(fileName.endsWith(".doc")){  
			type="application/msword;charset=utf-8";  
		}else if(fileName.endsWith(".pdf")){  
			type="application/pdf;charset=utf-8";  
		}  
		try {  
			//结局中文名字乱码的问题  
			fileName=new String(file.getName().getBytes("UTF-8"),"ISO-8859-1");  
		} catch ( Exception e ) {  
			// TODO: handle exception  
		}  
		return Response.ok(entity, type).header("Content-disposition", "inline;filename="+fileName).build();  
	}  
  
	//下载附件方法  
	private StreamingOutput downLoad(final File file) {  
		StreamingOutput entity=new StreamingOutput() {  
			  
			@Override  
			public void write(OutputStream output) throws IOException, WebApplicationException {  
				int len=0;  
				byte[] buffer=new byte[1024];  
				InputStream intpStream=new FileInputStream(file);  
				while((len = intpStream.read(buffer))>0){  
					output.write(buffer, 0,len);  
				}  
				intpStream.close();  
				output.flush();  
				output.close();  
				  
			}  
		};  
		return entity;  
	}  
}

restful层的配置文件：

解析前端传来的参数：

package com.gzydt.oa.util;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import net.sf.json.JSONObject;
import com.gzydt.oa.commons.QueryParam;
public class QueryUtil {
	/**
	 * 解析url中的查询条件的参数
	 *
	 * @param query
	 *			:查询标示
	 * @param queryParam
	 *			:url中的查询参数
	 * @return 为空
	 */
	public static void prepareQuery(String query, QueryParam queryParam) {
		try {
			JSONObject jo = JSONObject.fromObject(query);
			Map param = new HashMap();
			List sorts = new ArrayList();
			for ( @SuppressWarnings("unchecked")
			Iterator iterator = jo.keySet().iterator(); iterator.hasNext(); ) {
				String key = iterator.next();
				String value = jo.optString(key);
				if ( !value.isEmpty() ) {
					if ( "sort".equals(key) ) {
						for ( String s : value.split(",") ) {
							if ( null != s ) {
								if ( s.startsWith("8") ) {// 前端无法传“+”
									s = "+" + s.substring(1, s.length());
								} else {
									s = "-" + s.substring(1, s.length());
								}
								sorts.add(s);
							}
						}
					} else {
						param.put(key, value);
					}
				}
			}
			queryParam.setParam(param);
			queryParam.setSorts(sorts);
		} catch ( Exception e ) {
			e.printStackTrace();
		}
	}
}

内部邮件的测试类：

package com.gzydt.oa.resource;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.util.ArrayList;
import java.util.List;
import org.apache.commons.httpclient.HttpClient;
import org.apache.commons.httpclient.HttpException;
import org.apache.commons.httpclient.NameValuePair;
import org.apache.commons.httpclient.methods.DeleteMethod;
import org.apache.commons.httpclient.methods.GetMethod;
import org.apache.commons.httpclient.methods.PostMethod;
import org.apache.commons.httpclient.methods.PutMethod;
import org.apache.commons.httpclient.methods.RequestEntity;
import org.apache.commons.httpclient.methods.StringRequestEntity;
import org.apache.commons.httpclient.methods.multipart.FilePart;
import org.apache.commons.httpclient.methods.multipart.MultipartRequestEntity;
import org.apache.commons.httpclient.methods.multipart.Part;
import org.apache.commons.httpclient.methods.multipart.StringPart;
import org.apache.commons.httpclient.params.HttpMethodParams;
import org.json.JSONObject;
import org.junit.Assert;
import org.junit.Test;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
public class MailTest extends Tester {
	private static final String TEST_URL = "http://localhost:8181/cxf/oa/mails";
	private static final Logger LOG = LoggerFactory.getLogger(MailTest.class);
	/**
	 * 登记信息写邮件
	 *
	 * @throws FileNotFoundException
	 */
	@Test
	public void uploadOrigText() throws FileNotFoundException {
		/*
		 * JSONObject jo = new JSONObject(); jo.put("subject", "周末计划");// 主题
		 * jo.put("toMails", "aa<13>,bb<2>");// 收件人 格式 ：姓名;姓名
		 * jo.put("urgency", "加急");// 紧急程度 jo.put("sendDate", "2015-4-11");//
		 * 发布日期 jo.put("content", "周末购物");// 邮件内容 jo.put("mailUser", "14");//
		 * 邮件拥有者 格式：userId jo.put("sendMail", "cc<14>");// 邮件发送者
		 * 格式：姓名,若只是新建，则不需要改字段 jo.put("type", "0");//
		 * 状态标示：-1删除；0草稿；1发送；2未读收件，3已读收件 //新增不需要增加type
		 */
		// 要上传的文件
		String path = "F:\\1.doc";
		String path2 = "F:\\3.doc";
		long start = System.currentTimeMillis();
		File file = new File(path);
		File fileText = new File(path2);
		// 'type': '0',
		String content = "{ 'content': '周末野炊','sendDate': '2015-04-11',
'toMails': 'aa<13>,bb<2>','mailUser': '14','subject': '周末计划','sendMail': '','urgency': '加急'}";
		Part[] parts = { new FilePart("file", file, "application/octet-stream", "UTF-8"),
				new FilePart("file", fileText, "application/octet-stream", "UTF-8"),
new StringPart("content", content, "UTF-8") };
		PostMethod post = new PostMethod(TEST_URL);
		post.setRequestEntity(new MultipartRequestEntity(parts, post.getParams()));
		HttpClient httpclient = new HttpClient();
		String res = "";
		try {
			int result = httpclient.executeMethod(post);
			LOG.info("Response status code: " + result);
			LOG.info("Response body: ");
			res = getStringFromInputStream(post.getResponseBodyAsStream());
			LOG.info(res);
		} catch ( Exception e ) {
			LOG.error("Error connecting to {}", TEST_URL);
			Assert.fail("Connection error");
		} finally {
			// Release current connection to the connection pool once you
			// are
			// done
			post.releaseConnection();
		}
		LOG.info("断言：验证成功返回【ok】响应！");
		Assert.assertTrue("ok".equals(res));
		long end = System.currentTimeMillis();
		LOG.info("验证用时（毫秒）：" + (end - start));
	}
	/**
	 * 发邮件
	 * @throws Exception
	 * @throws FileNotFoundException
	 */
	@Test
	public void sendEmail() throws Exception {
		long id = 2l;
		LOG.info("开始测试发送邮件");
		PostMethod post = new PostMethod(TEST_URL +"/sendMails/"+ id);
		post.addRequestHeader("Accept", "application/json");
		post.getParams().setParameter(HttpMethodParams.HTTP_CONTENT_CHARSET, "UTF-8");
	  
		   /* JSONObject jo = new JSONObject();
			jo.put("subject", "周末计划");// 主题
			jo.put("toMails", "aa<13>,bb<2>");// 收件人 格式 ：姓名;姓名
			jo.put("urgency", "加急");// 紧急程度
			jo.put("sendDate", "2015-4-11");// 发布日期
			jo.put("content", "周末购物");// 邮件内容
			jo.put("mailUser", "14");// 邮件拥有者 格式：userId
			jo.put("sendMail", "cc<14>");// 邮件发送者 格式：姓名,若只是新建，则不需要改字段
*/		  //  LOG.debug("设置请求参数：" + jo.toString());
		JSONObject jo = new JSONObject();
			RequestEntity entity = new StringRequestEntity(jo.toString(), "application/json", "UTF-8");
			post.setRequestEntity(entity);
			HttpClient httpclient = new HttpClient();
			String res = "";
			LOG.info("发送post请求");
			int result = httpclient.executeMethod(post);
			LOG.info(" 响应状态：" + result);
			res = this.getStringFromInputStream(post.getResponseBodyAsStream());
			LOG.info("响应结果：：" + res);
			LOG.info("断言：");
		  
	  
	}
	// 将邮件放进回收站，是将状态改为-1
	@Test
	public void updateTest() throws FileNotFoundException {
		LOG.info("开始测试更新");
		long id = 1;
		PutMethod put = new PutMethod(TEST_URL + "/" + id);
		// 要上传的文件
		String path = "F:\\1.doc";
		String path2 = "F:\\3.doc";
		long start = System.currentTimeMillis();
		File file = new File(path);
		File fileText = new File(path2);
		String content = "{ 'content': '周末加班','sendDate': '2015-4-11','toMails': 'aa<13>,bb<2>',
'mailUser': '14','subject': '周末计划','type': '0','sendMail': '','urgency': '加急'}";
		Part[] parts = { new FilePart("file", file, "application/octet-stream", "UTF-8"),
				new FilePart("file", fileText, "application/octet-stream", "UTF-8"),
new StringPart("content", content, "UTF-8") };
		put.addRequestHeader("Accept", "application/json");
		put.getParams().setParameter(HttpMethodParams.HTTP_CONTENT_CHARSET, "UTF-8");
		put.setRequestEntity(new MultipartRequestEntity(parts, put.getParams()));
		HttpClient httpclient = new HttpClient();
		String res = "";
		try {
			int result = httpclient.executeMethod(put);
			LOG.info("Response status code: " + result);
			LOG.info("Response body: ");
			res = getStringFromInputStream(put.getResponseBodyAsStream());
			LOG.info(res);
		} catch ( Exception e ) {
			LOG.error("Error connecting to {}", TEST_URL);
			Assert.fail("Connection error");
		} finally {
			put.releaseConnection();
		}
		LOG.info("断言：验证成功返回【ok】响应！");
		Assert.assertTrue("ok".equals(res));
		long end = System.currentTimeMillis();
		LOG.info("验证用时（毫秒）：" + (end - start));
	}
	/**
	 * 根据特定的id来找到值班人员的用户信息
	 */
	@Test
	public void findTest() {
		long id = 15L;
		GetMethod get = new GetMethod(TEST_URL + "/" + id);
		HttpClient client = new HttpClient();
		String res = "";
		try {
			int retCode = client.executeMethod(get);
			LOG.info("响应状态 " + retCode);
			res = this.getStringFromInputStream(get.getResponseBodyAsStream());
			LOG.info("响应结果" + res);
		} catch ( Exception e ) {
			LOG.error("该url路径出错，服务未开启，请检查", TEST_URL + "/" + id);
			Assert.fail("连接失败.");
		} finally {
			get.releaseConnection();
		}
	}
	@Test
	public void queryTest() {
		LOG.info("开始测试分页查询");
		GetMethod get = new GetMethod(TEST_URL + "/list");
		get.getParams().setParameter(HttpMethodParams.HTTP_CONTENT_CHARSET, "UTF-8");
		List params = new ArrayList();
		// 设置分页有信息
		get.setRequestHeader("Range", "items=0-9");
		JSONObject jo = new JSONObject();
		LOG.debug("请求参数：：" + jo.toString());
		// jo.put("mailUser", "14");
		jo.put("sendDate", "2015-01-10~2015-01-13");
		/*
		 * jo.put("type", "0"); jo.put("content","周末");
		 */
		// jo.put("issueDate", "2015-01-10~2015-02-24");
		// jo.put("sendFileDate", "2015-01-14~2015-02-04");
		// jo.put("getFileDate", "2015-01-11~2015-02-04");
		// jo.put("fromUnit", "Scgovernment");
		/* jo.put("issueDate", "2015-3") */
		// jo.put("number","Yfp");
		// jo.put("refNumber", "a11111");
		// jo.put("sendUnit", "Shengbangongting");
		// jo.put("title","22222");
		JSONObject jb = new JSONObject();
		params.add(new NameValuePair("query", jo.toString()));// 从0开始的
		get.setQueryString(params.toArray(new NameValuePair[0]));
		HttpClient httpClient = new HttpClient();
		String res = "";
		try {
			int result = httpClient.executeMethod(get);
			LOG.info("响应状态 " + result);
			res = this.getStringFromInputStream(get.getResponseBodyAsStream());
			LOG.info("响应结果 " + res);
		} catch ( Exception e ) {
			LOG.error("该url路径出错，服务未开启，请检查", TEST_URL);
			Assert.fail("连接失败.");
		} finally {
			get.releaseConnection();
		}
	}
	/**
	 * 测试删除周知事项
	 */
	@Test
	public void TestDelete() {
		LOG.info("开始测试删除通知");
		long id = 1L;
		DeleteMethod delete = new DeleteMethod(TEST_URL + "/" + id);
		HttpClient client = new HttpClient();
		String res = "";
		try {
			LOG.info("发送delete请求删除通知");
			int retCode = client.executeMethod(delete);
			LOG.info("响应状态：" + retCode);
			res = this.getStringFromInputStream(delete.getResponseBodyAsStream());
			LOG.info("响应结果: " + res);
		} catch ( Exception e ) {
			LOG.error("测试错误", e);
			Assert.fail("连接出错");
		} finally {
			/* 释放url的资源 */
			delete.releaseConnection();
		}
		LOG.info(res);
	}
}

在添加一个正常的测试新增的方法：

@Test
public void testAdd(){
  LOG.info("开始测试增加");
  PostMethod post = new PostMethod(TEST_URL);
  post.addRequestHeader("Accept", "application/json");
  post.getParams().setParameter(HttpMethodParams.HTTP_CONTENT_CHARSET,
	"UTF-8");
  try {
   JSONObject jo = new JSONObject();
  
   jo.put("day", "2015-4-10");
   jo.put("type", "0");
   jo.put("content", "gfdz参加了2014年广东省某某某某活动");
   jo.put("mainLeaderIds", "2,3");
   jo.put("relevantLeaderIds", "5,6");
   // date
   jo.put("goverEvent", true);
   jo.put("ownEvent", false);
   jo.put("ownerId", "2");
   LOG.debug("设置请求参数：" + jo.toString());
   RequestEntity entity = new StringRequestEntity(
	 jo.toString(), "application/json", "UTF-8");
   post.setRequestEntity(entity);
   HttpClient httpclient = new HttpClient();
   String res = "";
   LOG.info("发送post请求");
   int result = httpclient.executeMethod(post);
   LOG.info(" 响应状态：" + result);
   res = this.getStringFromInputStream(post.getResponseBodyAsStream());
   LOG.info("响应结果：：" + res);
   Assert.assertTrue(res.contains("增加值班表"));
  } catch (Exception e) {
   LOG.error("测试错误", e);
   Assert.fail("连接出错");
  } finally {
   post.releaseConnection();
  }
}

关于java中JPA动态查询语句的用法就分享到这里了，希望以上内容可以对大家有一定的帮助，可以学到更多知识。如果觉得文章不错，可以把它分享出去让更多的人看到。

网站标题：java中JPA动态查询语句的用法
网页网址：http://hbruida.cn/article/gjcjoj.html