JPA|JPA 使用criteria简单查询工具类方式

目录

  • 使用criteria简单查询工具类
    • 首先创建类并实现Specification接口
    • 新建ExpandCriterion接口
    • 使用criteria前提是dao接口必须实现JpaSpecificationExecutor接口
  • 打包JPA动态查询(CriteriaQuery) eq、ge、gt
    • 封装JPA动态查询(CriteriaQuery)
    • EntityManager管理器,通过spring管理
    • Page分页和结果封装类
    • IBaseDao接口实现了BaseDaoImpl
    • IBaseDao接口

使用criteria简单查询工具类 以前用jpa写了一个条件筛选的查询数据如下,才知道那么渣渣,就是一个表,根据前端来筛选数据,写的如下
JPA|JPA 使用criteria简单查询工具类方式
文章图片

首先就是判断前端传来的参数就写了那么多,现在才发现是渣渣中的渣渣,而且还费时,用criteria很快就搞定

首先创建类并实现Specification接口
import java.util.ArrayList; import java.util.List; import javax.persistence.criteria.CriteriaBuilder; import javax.persistence.criteria.CriteriaQuery; import javax.persistence.criteria.Predicate; import javax.persistence.criteria.Root; import org.springframework.data.jpa.domain.Specification; public class ExpandCriteria implements Specification{private List criterions = new ArrayList(); public Predicate toPredicate(Root root, CriteriaQuery query,CriteriaBuilder builder) {if (!criterions.isEmpty()) {List
predicates = new ArrayList
(); for(ExpandCriterion c : criterions){predicates.add(c.toPredicate(root, query,builder)); }// 将所有条件用 and 联合起来if (predicates.size() > 0) {return builder.and(predicates.toArray(new Predicate[predicates.size()])); }}return builder.conjunction(); }/** * 增加简单条件表达式 * @Methods Name add * @Create In 2012-2-8 By lee * @param expression0 void */public void add(ExpandCriterion criterion){if(criterion!=null){criterions.add(criterion); }}public static void main(String[] args) {//使用示例Demo//Criteria c = new Criteria(); //c.add(Restrictions.like("code", searchParam.getCode(), true)); //c.add(Restrictions.eq("level", searchParam.getLevel(), false)); //c.add(Restrictions.eq("mainStatus", searchParam.getMainStatus(), true)); //c.add(Restrictions.eq("flowStatus", searchParam.getFlowStatus(), true)); //c.add(Restrictions.eq("createUser.userName", searchParam.getCreateUser(), true)); //c.add(Restrictions.lte("submitTime", searchParam.getStartSubmitTime(), true)); //c.add(Restrictions.gte("submitTime", searchParam.getEndSubmitTime(), true)); //c.add(Restrictions.eq("needFollow", searchParam.getIsfollow(), true)); //c.add(Restrictions.ne("flowStatus", searchParam.getMainStatus() true)); //c.add(Restrictions.in("solveTeam.code",teamCodes, true)); //repository.findAll(c); }}


新建ExpandCriterion接口
import javax.persistence.criteria.CriteriaBuilder; import javax.persistence.criteria.CriteriaQuery; import javax.persistence.criteria.Predicate; import javax.persistence.criteria.Root; public interface ExpandCriterion {public enum Operator {EQ, NE, LIKE, GT, LT, GTE, LTE, AND, OR}public Predicate toPredicate(Root root, CriteriaQuery query,CriteriaBuilder builder); }

新建Restrictions.java
import java.util.Collection; import org.springframework.util.StringUtils; import com.sll.iot.dao.base.criteria.ExpandCriterion.Operator; public class Restrictions {/** * 等于 * @param fieldName * @param value * @param ignoreNull * @return */public static SimpleExpression eq(String fieldName, Object value, boolean ignoreNull) {if(StringUtils.isEmpty(value))return null; return new SimpleExpression (fieldName, value, Operator.EQ); }/** * 不等于 * @param fieldName * @param value * @param ignoreNull * @return */public static SimpleExpression ne(String fieldName, Object value, boolean ignoreNull) {if(StringUtils.isEmpty(value))return null; return new SimpleExpression (fieldName, value, Operator.NE); }/** * 模糊匹配 * @param fieldName * @param value * @param ignoreNull * @return */public static SimpleExpression like(String fieldName, String value, boolean ignoreNull) {if(StringUtils.isEmpty(value))return null; return new SimpleExpression (fieldName, value, Operator.LIKE); }/** * 大于 * @param fieldName * @param value * @param ignoreNull * @return */public static SimpleExpression gt(String fieldName, Object value, boolean ignoreNull) {if(StringUtils.isEmpty(value))return null; return new SimpleExpression (fieldName, value, Operator.GT); }/** * 小于 * @param fieldName * @param value * @param ignoreNull * @return */public static SimpleExpression lt(String fieldName, Object value, boolean ignoreNull) {if(StringUtils.isEmpty(value))return null; return new SimpleExpression (fieldName, value, Operator.LT); }/** * 大于等于 * @param fieldName * @param value * @param ignoreNull * @return */public static SimpleExpression lte(String fieldName, Object value, boolean ignoreNull) {if(StringUtils.isEmpty(value))return null; return new SimpleExpression (fieldName, value, Operator.GTE); }/** * 小于等于 * @param fieldName * @param value * @param ignoreNull * @return */public static SimpleExpression gte(String fieldName, Object value, boolean ignoreNull) {if(StringUtils.isEmpty(value))return null; return new SimpleExpression (fieldName, value, Operator.LTE); }/** * 并且 * @param criterions * @return */public static LogicalExpression and(ExpandCriterion... criterions){return new LogicalExpression(criterions, Operator.AND); }/** * 或者 * @param criterions * @return */public static LogicalExpression or(ExpandCriterion... criterions){return new LogicalExpression(criterions, Operator.OR); }/** * 包含于 * @param fieldName * @param value * @return */@SuppressWarnings("rawtypes")public static LogicalExpression in(String fieldName, Collection value, boolean ignoreNull) {if(ignoreNull&&(value=https://www.it610.com/article/=null||value.isEmpty())){return null; }SimpleExpression[] ses = new SimpleExpression[value.size()]; int i=0; for(Object obj : value){ses[i]=new SimpleExpression(fieldName,obj,Operator.EQ); i++; }return new LogicalExpression(ses,Operator.OR); }

新建SimpleExpression.java
import javax.persistence.criteria.CriteriaBuilder; import javax.persistence.criteria.CriteriaQuery; import javax.persistence.criteria.Expression; import javax.persistence.criteria.Path; import javax.persistence.criteria.Predicate; import javax.persistence.criteria.Root; public class SimpleExpression implements ExpandCriterion{private String fieldName; //属性名private Object value; //对应值private Operator operator; //计算符 protected SimpleExpression(String fieldName, Object value, Operator operator) {this.fieldName = fieldName; this.value = https://www.it610.com/article/value; this.operator = operator; }public String getFieldName() {return fieldName; }public Object getValue() {return value; }public Operator getOperator() {return operator; }@SuppressWarnings({"rawtypes", "unchecked" })public Predicate toPredicate(Root root, CriteriaQuery query,CriteriaBuilder builder) {Path expression = null; if(fieldName.contains(".")){String[] names = fieldName.split("."); expression = root.get(names[0]); for (int i = 1; i < names.length; i++) {expression = expression.get(names[i]); }}else{expression = root.get(fieldName); }switch (operator) {case EQ:return builder.equal(expression, value); case NE:return builder.notEqual(expression, value); case LIKE:return builder.like((Expression) expression, "%" + value + "%"); case LT:return builder.lessThan(expression, (Comparable) value); case GT:return builder.greaterThan(expression, (Comparable) value); case LTE:return builder.lessThanOrEqualTo(expression, (Comparable) value); case GTE:return builder.greaterThanOrEqualTo(expression, (Comparable) value); default:return null; }}}

LogicalExpression.java
import java.util.ArrayList; import java.util.List; import javax.persistence.criteria.CriteriaBuilder; import javax.persistence.criteria.CriteriaQuery; import javax.persistence.criteria.Predicate; import javax.persistence.criteria.Root; public class LogicalExpression implements ExpandCriterion {private ExpandCriterion[] criterion; // 逻辑表达式中包含的表达式private Operator operator; //计算符public LogicalExpression(ExpandCriterion[] criterions, Operator operator) {this.criterion = criterions; this.operator = operator; }public Predicate toPredicate(Root root, CriteriaQuery query,CriteriaBuilder builder) {List
predicates = new ArrayList
(); for(int i=0; i

使用criteria前提是dao接口必须实现JpaSpecificationExecutor接口
改造如下
//条件查询 @Override public Paging query(Paging paging,String channelName,String operator) {Pageable pageReq = new PageRequest(paging.getCurrentPage()-1, paging.getPageSize()); Page pageChanel=null; ExpandCriteria criteria = new ExpandCriteria(); if(StringUtil.isNotEmpty(channelName)){criteria.add(Restrictions.like("name", channelName, false)); }if(StringUtil.isNotEmpty(operator)){criteria.add(Restrictions.eq("operator",Operator.valueOf(operator), false)); }pageChanel=channelRepository.findAll(criteria, pageReq); if(pageChanel!=null){paging.setTotalCount((int)pageChanel.getTotalElements()); paging.setData(pageChanel.getContent()); paging.setTotalPage(pageChanel.getTotalPages()); }return paging; }

【JPA|JPA 使用criteria简单查询工具类方式】都不用在dao接口写什么东西
使用方法就是demo
public static void main(String[] args) {//使用示例Demo//Criteria c = new Criteria(); //c.add(Restrictions.like("code", searchParam.getCode(), true)); //c.add(Restrictions.eq("level", searchParam.getLevel(), false)); //c.add(Restrictions.eq("mainStatus", searchParam.getMainStatus(), true)); //c.add(Restrictions.eq("flowStatus", searchParam.getFlowStatus(), true)); //c.add(Restrictions.eq("createUser.userName", searchParam.getCreateUser(), true)); //c.add(Restrictions.lte("submitTime", searchParam.getStartSubmitTime(), true)); //c.add(Restrictions.gte("submitTime", searchParam.getEndSubmitTime(), true)); //c.add(Restrictions.eq("needFollow", searchParam.getIsfollow(), true)); //c.add(Restrictions.ne("flowStatus", searchParam.getMainStatus() true)); //c.add(Restrictions.in("solveTeam.code",teamCodes, true)); //repository.findAll(c); }


打包JPA动态查询(CriteriaQuery) eq、ge、gt
封装JPA动态查询(CriteriaQuery)
JPA动态查询(CriteriaQuery)封装的一段代码:
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 * @author:lry * @since:2014-05-23 */@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 =https://www.it610.com/article/= null ||"".equals(value); }return value =https://www.it610.com/article/= 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 = "https://www.it610.com/article/%" + 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 =https://www.it610.com/article/= 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 = "https://www.it610.com/article/%" + 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 =https://www.it610.com/article/= 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; }}

insertupdatedelete

package com.platform.framework.dao.jpa; import javax.persistence.EntityManager; import javax.persistence.EntityManagerFactory; import javax.persistence.EntityTransaction; import org.apache.log4j.Logger; import org.aspectj.lang.ProceedingJoinPoint; import org.aspectj.lang.Signature; /** * @describe JPA事务管理 * @author lry * @since:2014-05-23 * */public class TransactionHandler {private static final Logger log = Logger.getLogger(TransactionHandler.class); private String[] txmethod; // 配置事务的传播特性方法private EntityManagerFactory entityManagerFactory; // JPA工厂public Object exec(ProceedingJoinPoint point) throws Throwable {Signature signature = point.getSignature(); log.debug(point.getTarget().getClass().getName() + "."+ signature.getName() + "()"); Boolean isTransaction = false; for (String method : txmethod) {if (signature.getName().startsWith(method)) {// 以method开头的方法打开事务isTransaction = true; break; }}// JPA->Hibernateif (point.getTarget() instanceof EntityManagerFactoryProxy) {// 获得被代理对象EntityManagerFactoryProxy emfp = (EntityManagerFactoryProxy) point.getTarget(); EntityManager em = emfp.getEntityManager(); if (em != null) {// 如果对象已经有em了就不管return point.proceed(); } else {em = entityManagerFactory.createEntityManager(); }log.debug("JPA->Hibernate open connection..."); if (isTransaction) {EntityTransaction t = null; try {// 打开连接并开启事务log.debug("JPA->Hibernate begin transaction..."); t = em.getTransaction(); if (!t.isActive())t.begin(); emfp.setEntityManager(em); Object obj = point.proceed(); // 提交事务log.debug("JPA->Hibernate commit..."); t.commit(); return obj; } catch (Exception e) {if (t != null) {log.debug("JPA->Hibernate error...,rollback..."+ e.getMessage()); t.rollback(); }e.printStackTrace(); throw e; } finally {if (em != null && em.isOpen()) {// 关闭连接em.close(); log.debug("JPA->Hibernate close connection..."); }emfp.setEntityManager(null); }} else {try {emfp.setEntityManager(em); return point.proceed(); } catch (Exception e) {log.debug("JPA->Hibernate error..." + e.getMessage()); e.printStackTrace(); throw e; } finally {if (em != null && em.isOpen()) {// 关闭连接em.close(); log.debug("JPA->Hibernate close connection..."); }emfp.setEntityManager(null); }}} else {return point.proceed(); }}public String[] getTxmethod() {return txmethod; }public void setTxmethod(String[] txmethod) {this.txmethod = txmethod; }public void setEntityManagerFactory(EntityManagerFactory entityManagerFactory) {this.entityManagerFactory = entityManagerFactory; }}


EntityManager管理器,通过spring管理
package com.platform.framework.dao.jpa; import java.util.Collection; import javax.persistence.EntityManager; import javax.persistence.EntityManagerFactory; /** * EntityManager管理器 * * @author:yangjian1004 * @since:2011-11-30 16:14:24 AM */public class EntityManagerFactoryProxy {private static ThreadLocal emThreadLocal = new ThreadLocal(); private static EntityManagerFactory emf; public void setEmf(EntityManagerFactory emf) {EntityManagerFactoryProxy.emf = emf; }public static EntityManagerFactory getEmf() {return emf; }public EntityManager getEntityManager() {return emThreadLocal.get(); }public void setEntityManager(EntityManager em) {emThreadLocal.set(em); }/** * 创建查询条件 ** @param name *字段名称 * @param values *字段值 */public String createInCondition(String name, Collection values) {if (values == null || values.size() == 0) {return "1<>1"; }StringBuffer sb = new StringBuffer(); sb.append(name + " in("); for (String id : values) {sb.append("'" + id + "',"); }String hsqlCondition = sb.substring(0, sb.length() - 1) + ")"; return hsqlCondition; }}


Page分页和结果封装类
package com.platform.framework.dao.jpa; import java.io.Serializable; import java.util.ArrayList; import java.util.List; /** * Page基类
* * @describe:分页 */public class Page implements Serializable {private static final long serialVersionUID = 665620345605746930L; /** 总条数 */private int count; /** 页码 */private int pageNo; /** 每页显示多少条 */private int rowsPerPage; /** 总页数 */private int totalPageCount; /** 起始条数 */private int firstRow; /** 结束条数 */private int lastRow; /** 查询结果集合形式的结果 */private List result; /** 查询结果对象形式的结果 */public Object obj; public Integer code; // 返回码private boolean success = true; private String message; public Page() {}public Page(List list) {this(list.size(), 1, list.size(), list); }public Page(int count, int pageNo, int rowsPerPage, List result) {if (rowsPerPage < 1) {rowsPerPage = 1; }this.count = count; this.pageNo = pageNo; this.result = result; this.rowsPerPage = rowsPerPage; if (this.result == null)this.result = new ArrayList(); totalPageCount = count / rowsPerPage; if (count - (count / rowsPerPage) * rowsPerPage > 0)totalPageCount++; if (count == 0) {totalPageCount = 0; pageNo = 0; }firstRow = (pageNo - 1) * rowsPerPage + 1; if (count == 0) {firstRow = 0; }lastRow = (pageNo) * rowsPerPage; if (lastRow > count) {lastRow = count; }}/** 返回每页的条数 */public int getCount() {return count; }public List getResult() {return result; }public int getPageNo() {return pageNo; }/** 返回每页的条数 */public int getRowsPerPage() {return rowsPerPage; }/** 返回总的页数 */public int getTotalPageCount() {return totalPageCount; }public void setPageNo(int pageNo) {this.pageNo = pageNo; }public void setRowsPerPage(int rowsPerPage) {this.rowsPerPage = rowsPerPage; }public int getFirstRow() {return firstRow; }public int getLastRow() {return lastRow; }public void setFirstRow(int firstRow) {this.firstRow = firstRow; }public void setLastRow(int lastRow) {this.lastRow = lastRow; }public void setCount(int count) {this.count = count; }public void setTotalPageCount(int totalPageCount) {this.totalPageCount = totalPageCount; }public void setResult(List result) {this.result = result; }public Object getObj() {return obj; }public void setObj(Object obj) {this.obj = obj; }public boolean isSuccess() {return success; }public void setSuccess(boolean success) {this.success = success; }public String getMessage() {return message; }public void setMessage(String message) {this.message = message; }/** * 计算起始条数 */public static int calc(int pageNo, int rowsPerPage, int count) {if (pageNo <= 0)pageNo = 1; if (rowsPerPage <= 0)rowsPerPage = 10; // 当把最后一页数据删除以后,页码会停留在最后一个上必须减一int totalPageCount = count / rowsPerPage; if (pageNo > totalPageCount && (count % rowsPerPage == 0)) {pageNo = totalPageCount; }if (pageNo - totalPageCount > 2) {pageNo = totalPageCount + 1; }int firstRow = (pageNo - 1) * rowsPerPage; if (firstRow < 0) {firstRow = 0; }return firstRow; }}


IBaseDao接口实现了BaseDaoImpl
package com.platform.framework.dao.jpa; import java.io.Serializable; import java.util.List; import javax.persistence.EntityManager; import javax.persistence.criteria.CriteriaQuery; import javax.persistence.criteria.Predicate; import javax.persistence.criteria.Selection; import javax.persistence.metamodel.EntityType; import org.apache.log4j.Logger; import com.google.common.base.Strings; /** * IBaseDao接口实现了BaseDaoImpl类
*/@SuppressWarnings({ "unchecked", "rawtypes" })public class BaseDaoImpl extends EntityManagerFactoryProxy implements IBaseDao {private static Logger log = Logger.getLogger(BaseDaoImpl.class); /** 每次批量操作数 */private int batchSize = 50; /** 设置每次操作数 */public void setBatchSize(int batchSize) {this.batchSize = batchSize; }public E get(Class clazz, Serializable id) {return (E) getEntityManager().find(clazz, id); }/** * 插入记录 ** @param entity *要插入的记录 */public void insert(Object entity) {if (entity instanceof List) {insertList((List) entity); return; } else if (entity instanceof Object[]) {return; }try {getEntityManager().persist(entity); } catch (Exception e) {e.printStackTrace(); }}/** * 批量增加 ** @param list *要新增的数据 */public void insertList(List list) {EntityManager entityManager = getEntityManager(); if (list == null || list.size() == 0) {return; }int i = 0; for (Object o : list) {insert(o); if (i % batchSize == 0) {entityManager.flush(); }i++; }log.debug(list.get(0).getClass() + "批量增加数据" + i + "条"); }/** * 更新记录 ** @param entity *要更新的记录 */public void update(Object entity) {if (entity instanceof List) {this.updateList((List) entity); return; }getEntityManager().merge(entity); }/** 更新list */public void updateList(List list) {for (Object entity : list) {this.update(entity); }}/** * 删除记录 ** @param entity *要删除的记录 */public void delete(Object entity) {if (entity instanceof List) {List list = (List) entity; for (Object o : list) {getEntityManager().remove(o); }} else {getEntityManager().remove(entity); }}public List query(String jpql) {return getEntityManager().createQuery(jpql).getResultList(); }public Integer updateJpql(String jpql) {return getEntityManager().createQuery(jpql).executeUpdate(); }public Integer updateSql(String sql) {return getEntityManager().createNativeQuery(sql).executeUpdate(); }public List queryBySql(String sql) {return getEntityManager().createNativeQuery(sql).getResultList(); }/** * 查询记录 ** @param clazz *要查询的实体类 * @param hqlCondition *查询条件 */public List query(Class clazz, String hqlCondition) {return getEntityManager().createQuery("select t from " + clazz.getName() + " as t where " + hqlCondition).getResultList(); }public void delete(Class entity, String jpqlCondition) {if (Strings.isNullOrEmpty(jpqlCondition)) {jpqlCondition = "1=1"; }int no = updateJpql("delete " + entity.getName() + " where " + jpqlCondition); log.debug(entity.getName() + "删除" + no + "条数据"); }/** * 根据ids删除数据 ** @param entity *删除实体类 * @param ids *删除条件 */public void delete(Class entity, List ids) {String idName = getIdName(entity, getEntityManager()); StringBuffer sb = new StringBuffer(); sb.append(idName + " in("); for (int i = 0; i < ids.size(); i++) {sb.append("'" + ids.get(i) + "',"); }String jpqlCondition = sb.substring(0, sb.length() - 1) + ")"; delete(entity, jpqlCondition); }public List query(String jpql, int firstResult, int maxResults) {List result = getEntityManager().createQuery(jpql).setFirstResult(firstResult).setMaxResults(maxResults).getResultList(); return result; }public List queryBySql(String sql, int firstResult, int maxResults) {return getEntityManager().createNativeQuery(sql).setFirstResult(firstResult).setMaxResults(maxResults).getResultList(); }public List queryAll(Class clazz) {CriteriaQuery criteriaQuery = getEntityManager().getCriteriaBuilder().createQuery(clazz); criteriaQuery.from(clazz); return getEntityManager().createQuery(criteriaQuery).getResultList(); }public Page queryPageByJpql(String jpql, int pageNo, int rowsPerPage) {if (pageNo <= 0)pageNo = 1; if (rowsPerPage <= 0)rowsPerPage = 7; log.debug("-----开始查询,页码:" + pageNo + ",每页显示:" + rowsPerPage + "----"); String countJpql = "select count(*) from (" + jpql + ")"; int count = getCount(countJpql).intValue(); // 当把最后一页数据删除以后,页码会停留在最后一个上必须减一int totalPageCount = count / rowsPerPage; if (pageNo > totalPageCount && (count % rowsPerPage == 0)) {pageNo = totalPageCount; }if (pageNo - totalPageCount > 2) {pageNo = totalPageCount + 1; }int firstResult = (pageNo - 1) * rowsPerPage; if (firstResult < 0) {firstResult = 0; }List result = getEntityManager().createQuery(jpql).setFirstResult(firstResult).setMaxResults(rowsPerPage).getResultList(); return new Page(count, pageNo, rowsPerPage, result); }public Long getCount(String jpql) {return (Long) getEntityManager().createQuery(jpql).getResultList().get(0); }/*** ** @Method updateJpql * @Description 根据传入的带有占位符的sql语句, 做增删改操作 例如 *updateJpql("update user t set t.name=? where t.id=?" *,{[zhongxiang],[23]}) * @Author 钟翔/zhongxiang * @Date 2012-8-9 下午3:38:35 * @param jpql *占位符式的sql * @param paramList *list里面装有[zhongxiang , 23] */public void updateJpql(String jpql, List paramList) {javax.persistence.Query query = getEntityManager().createQuery(jpql); for (int i = 0; i < paramList.size(); i++) {query.setParameter(i + 1, paramList.get(i)); }query.executeUpdate(); }/** * 统计记录 ** @param query *统计条件 */public Long getCount(Query query) {Selection selection = query.getCriteriaQuery().getSelection(); query.getCriteriaQuery().select(query.getCriteriaBuilder().count(query.getFrom())); Long count = (Long) getEntityManager().createQuery(query.newCriteriaQuery()).getResultList().get(0); query.getCriteriaQuery().select(selection); return count; }/** * 分页查询 ** @param query *查询条件 * @param pageNo *页号 * @param rowsPerPage *每页显示条数 */public Page queryPage(Query query, int pageNo, int rowsPerPage) {if (pageNo <= 0)pageNo = 1; if (rowsPerPage <= 0)rowsPerPage = 7; log.debug(query.getClazz() + "-----开始查询,页码:" + pageNo + ",每页显示:" + rowsPerPage + "----"); log.debug("查询条件:"); for (Predicate cri : query.getPredicates())log.debug(cri); int count = getCount(query).intValue(); // 当把最后一页数据删除以后,页码会停留在最后一个上必须减一int totalPageCount = count / rowsPerPage; if (pageNo > totalPageCount && (count % rowsPerPage == 0)) {pageNo = totalPageCount; }if (pageNo - totalPageCount > 2) {pageNo = totalPageCount + 1; }int firstResult = (pageNo - 1) * rowsPerPage; if (firstResult < 0) {firstResult = 0; }List result = getEntityManager().createQuery(query.newCriteriaQuery()).setFirstResult(firstResult).setMaxResults(rowsPerPage).getResultList(); return new Page(count, pageNo, rowsPerPage, result); }/** * 根据query查找记录 ** @param query *查询条件 * @param firstResult *起始行 * @param maxResults *结束行 */public List query(Query query, int firstResult, int maxResults) {List result = getEntityManager().createQuery(query.newCriteriaQuery()).setFirstResult(firstResult).setMaxResults(maxResults).getResultList(); return result; }/** * 根据query查找记录 ** @param query *查询条件 */public List query(Query query) {return getEntityManager().createQuery(query.newCriteriaQuery()).getResultList(); }/** * 获得主键名称 ** @param clazz *操作是实体对象 * @param EntityManager *jpa的entityManager工厂 * @return 初建名称 * */public static String getIdName(Class clazz, EntityManager entityManager) {EntityType entityType = entityManager.getMetamodel().entity(clazz); return entityType.getId(entityType.getIdType().getJavaType()).getName(); }}


IBaseDao接口
package com.platform.framework.dao.jpa; import java.io.Serializable; import java.util.List; import javax.persistence.EntityManager; /** * IBaseDao基类
* * @describe:系统基础JPA Dao接口 */@SuppressWarnings({ "rawtypes" })public interface IBaseDao {public EntityManager getEntityManager(); public E get(Class clazz, Serializable id); /** * 插入记录 ** @param entity *要插入的记录 */public void insert(Object entity); /** * 更新记录 ** @param entity *要更新的记录 */public void update(Object entity); /** 更新list */public void updateList(List list); /** * 删除记录 ** @param entity *要删除的记录 */public void delete(Object entity); /** * 删除记录 ** @param entity *要删除的记录 */public void delete(Class entity, List ids); /** * 删除记录 ** @param entity *要删除的记录 */public void delete(Class entity, String jpqlCondition); /** * 统计记录 ** @param query *统计条件 */public Long getCount(Query query); public Long getCount(String jpql); /** * 分页查询 ** @param query *查询条件 * @param pageNo *页号 * @param rowsPerPage *每页显示条数 */public Page queryPage(Query query, int pageNo, int rowsPerPage); /** * 根据query查找记录 ** @param query *查询条件 * @param firstResult *起始行 * @param maxResults *结束行 */public List query(Query query, int firstResult, int maxResults); /** * 根据query查找记录 ** @param query *查询条件 */public List query(Query query); /** * 执行更新操作的jpql语句 ** @param jpql *要执行的jpql语句 */public List query(String jpql); public List queryAll(Class clazz); public List query(String jpql, int firstResult, int maxResults); /** * 执行查询操作的sql语句 ** @param sql *要执行的sql语句 */public List queryBySql(String sql); public List queryBySql(String sql, int firstResult, int maxResults); /** * 查询记录 ** @param clazz *要查询的实体类 * @param hqlCondition *查询条件 */public List query(Class clazz, String hqlCondition); /** * 执行更新操作的sql语句 ** @param sql *要执行的sql语句 */public Integer updateSql(String sql); public Integer updateJpql(String jpql); public Page queryPageByJpql(String hql, int pageNo, int rowsPerPage); public void updateJpql(String jpql, List paramList); }

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