最近接触的一个项目，看到之前他们写的Hibernate分页工具挺不错的，记录一下。
Dao层：
/**
*
*/
package com.zte.irobot.dao.impl;
import java.io.Serializable;
import java.lang.reflect.ParameterizedType;
import java.lang.reflect.Type;
import java.math.BigInteger;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Calendar;
import java.util.Collection;
import java.util.Date;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import javax.annotation.Resource;
import org.hibernate.Query;
import org.hibernate.SQLQuery;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.transform.Transformers;
import org.springframework.stereotype.Repository;
import com.zte.irobot.dao.BaseDao;
import com.zte.irobot.util.HibernateHandler;
import com.zte.irobot.util.ObjectUtil;
import com.zte.irobot.util.Pagination;
/**
* @author
*/
@Repository
public class BaseDaoImpl<T> implements BaseDao<T> {
protected Class<T> entityClazz;
protected SessionFactory sessionFactory;
@SuppressWarnings("unchecked")
public BaseDaoImpl() {
Type type = getClass().getGenericSuperclass();
if (type instanceof ParameterizedType) {
this.entityClazz = (Class<T>) ((ParameterizedType) type).getActualTypeArguments()[0];
} else {
this.entityClazz = null;
}
}
@Resource
public void setSessionFactory(SessionFactory sessionFactory) {
this.sessionFactory = sessionFactory;
}
protected Session getSession() {
return sessionFactory.getCurrentSession();
}
@SuppressWarnings("unchecked")
public Object save(Object entity) {
return (T) getSession().save(entity);
}
public void delete(Object entity) {
getSession().delete(entity);
}
public void update(Object entity) {
getSession().update(entity);
}
public void saveOrUpdate(Object entity) {
getSession().saveOrUpdate(entity);
}
public void saveAll(Collection<?> entities) {
for (@SuppressWarnings("rawtypes")
Iterator localIterator = entities.iterator(); localIterator.hasNext();) {
Object entity = localIterator.next();
getSession().save(entity);
}
}
public void deleteAll(Collection<?> entities) {
for (@SuppressWarnings("rawtypes")
Iterator localIterator = entities.iterator(); localIterator.hasNext();) {
Object entity = localIterator.next();
getSession().delete(entity);
}
}
public void updateAll(Collection<?> entities) {
for (@SuppressWarnings("rawtypes")
Iterator localIterator = entities.iterator(); localIterator.hasNext();) {
Object entity = localIterator.next();
getSession().update(entity);
}
}
public void saveOrUpdateAll(Collection<?> entities) {
for (@SuppressWarnings("rawtypes")
Iterator localIterator = entities.iterator(); localIterator.hasNext();) {
Object entity = localIterator.next();
getSession().saveOrUpdate(entity);
}
}
@SuppressWarnings({ "unchecked", "hiding" })
public <T> T get(Class<T> entityClass, Serializable id) {
return (T) getSession().get(entityClass, id);
}
@SuppressWarnings({ "unchecked", "rawtypes", "hiding" })
public <T> T get(CharSequence queryString, Object... params) {
Query qry = getSession().createQuery(queryString.toString());
for (int i = 0; i < params.length; ++i) {
qry.setParameter(i, params[i]);
}
List list = qry.setMaxResults(1).list();
if (list.isEmpty())
return null;
return (T) list.get(0);
}
@SuppressWarnings({ "unchecked", "hiding" })
public <T> T get(CharSequence queryString, Map<String, Object> params) {
Query qry = getSession().createQuery(queryString.toString());
setParameter(qry, params);
@SuppressWarnings("rawtypes")
List list = qry.setMaxResults(1).list();
if (list.isEmpty())
return null;
return (T) list.get(0);
}
@SuppressWarnings({ "unchecked", "hiding" })
public <T> List<T> findList(CharSequence queryString, Object... params) {
Query query = getSession().createQuery(queryString.toString());
for (int i = 0; i < params.length; ++i) {
query.setParameter(i, params[i]);
}
return query.list();
}
@SuppressWarnings({ "unchecked", "hiding" })
public <T> List<T> findList(CharSequence queryString, Map<String, Object> params) {
Query query = getSession().createQuery(queryString.toString());
setParameter(query, params);
return query.list();
}
@SuppressWarnings({ "unchecked", "hiding" })
public <T> Pagination<T> findPagination(CharSequence queryString, int pageIndex, int pageSize, Object... params) {
Query query = getSession().createQuery(queryString.toString());
if ((pageSize > 0) && (pageIndex > 0)) {
query.setFirstResult((pageIndex < 2) ? 0 : (pageIndex - 1) * pageSize);
query.setMaxResults(pageSize);
}
for (int i = 0; i < params.length; ++i) {
query.setParameter(i, params[i]);
}
@SuppressWarnings("rawtypes")
List items = query.list();
long rowsCount = 0L;
if ((pageSize > 0) && (pageIndex > 0)) {
String hql = parseSelectCount(queryString.toString());
rowsCount = ((Long) get(hql, params)).longValue();
} else {
rowsCount = items.size();
}
@SuppressWarnings("rawtypes")
Pagination pagination = new Pagination(pageIndex, pageSize, rowsCount);
pagination.setItems(items);
return pagination;
}
@SuppressWarnings({ "unchecked", "hiding" })
public <T> Pagination<T> findPagination(CharSequence queryString, Map<String, Object> params, int pageIndex,
int pageSize) {
Query query = getSession().createQuery(queryString.toString());
if ((pageSize > 0) && (pageIndex > 0)) {
query.setFirstResult((pageIndex < 2) ? 0 : (pageIndex - 1) * pageSize);
query.setMaxResults(pageSize);
}
setParameter(query, params);
@SuppressWarnings({ "rawtypes" })
List items = query.list();
long rowsCount = 0L;
if ((pageSize > 0) && (pageIndex > 0)) {
//String hql = parseSelectCount(queryString.toString());
//rowsCount = ((Long) get(hql, params)).longValue();
rowsCount = findList(queryString, params).size();
} else {
rowsCount = items.size();
}
@SuppressWarnings("rawtypes")
Pagination pagination = new Pagination(pageIndex, pageSize, rowsCount);
pagination.setItems(items);
return pagination;
}
@SuppressWarnings({ "unchecked", "hiding" })
public <T> Pagination<T> findPagination(CharSequence queryString, CharSequence countString, int pageIndex,
int pageSize, Object... params) {
Query query = getSession().createQuery(queryString.toString());
if ((pageSize > 0) && (pageIndex > 0)) {
query.setFirstResult((pageIndex < 2) ? 0 : (pageIndex - 1) * pageSize);
query.setMaxResults(pageSize);
}
for (int i = 0; i < params.length; ++i) {
query.setParameter(i, params[i]);
}
@SuppressWarnings("rawtypes")
List items = query.list();
long rowsCount = 0L;
if ((pageSize > 0) && (pageIndex > 0)) {
rowsCount = ((Long) get(countString, params)).longValue();
} else
rowsCount = items.size();
@SuppressWarnings("rawtypes")
Pagination pagination = new Pagination(pageIndex, pageSize, rowsCount);
pagination.setItems(items);
return pagination;
}
@SuppressWarnings({ "unchecked", "hiding" })
public <T> Pagination<T> findPagination(CharSequence queryString, CharSequence countString,
Map<String, Object> params, int pageIndex, int pageSize) {
Query query = getSession().createQuery(queryString.toString());
if ((pageSize > 0) && (pageIndex > 0)) {
query.setFirstResult((pageIndex < 2) ? 0 : (pageIndex - 1) * pageSize);
query.setMaxResults(pageSize);
}
setParameter(query, params);
@SuppressWarnings("rawtypes")
List items = query.list();
long rowsCount = 0L;
if ((pageSize > 0) && (pageIndex > 0)) {
rowsCount = ((Long) get(countString, params)).longValue();
} else
rowsCount = items.size();
@SuppressWarnings("rawtypes")
Pagination pagination = new Pagination(pageIndex, pageSize, rowsCount);
pagination.setItems(items);
return pagination;
}
@SuppressWarnings({ "serial", "unchecked", "hiding" })
public <T> Pagination<T> findSqlPagination(CharSequence queryString, final CharSequence countString,
final Map<String, Object> params, int pageIndex, int pageSize) {
SQLQuery query = getSession().createSQLQuery(queryString.toString());
query.setResultTransformer(Transformers.ALIAS_TO_ENTITY_MAP);
if ((pageSize > 0) && (pageIndex > 0)) {
query.setFirstResult((pageIndex < 2) ? 0 : (pageIndex - 1) * pageSize);
query.setMaxResults(pageSize);
}
if ((params != null) && (!(params.isEmpty()))) {
setParameter(query, params);
}
@SuppressWarnings("rawtypes")
List items = query.list();
BigInteger rowsCount = BigInteger.valueOf(0L);
if ((pageSize > 0) && (pageIndex > 0)) {
rowsCount = (BigInteger) executeQuery(new HibernateHandler() {
public Object doInHibernate(Session session) {
SQLQuery query = session.createSQLQuery(countString.toString());
if ((params != null) && (!(params.isEmpty()))) {
setParameter(query, params);
}
return query.uniqueResult();
}
});
}
@SuppressWarnings("rawtypes")
Pagination pagination = new Pagination(pageIndex, pageSize, rowsCount.intValue());
pagination.setItems(items);
return pagination;
}
public Object executeQuery(HibernateHandler handler) {
return handler.doInHibernate(getSession());
}
public void execute(String hql) {
executeUpdate(hql);
}
public void execute(HibernateHandler handler) {
executeUpdate(handler);
}
public void executeSql(String sql) {
executeSqlUpdate(sql);
}
public int executeSqlUpdate(String sql) {
return getSession().createSQLQuery(sql).executeUpdate();
}
public int executeUpdate(String hql) {
return getSession().createQuery(hql).executeUpdate();
}
public Object executeUpdate(HibernateHandler handler) {
return handler.doInHibernate(getSession());
}
protected Query setParameter(Query query, Map<String, Object> parameterMap) {
for (@SuppressWarnings("rawtypes")
Iterator iterator = parameterMap.keySet().iterator(); iterator.hasNext();) {
String key = (String) iterator.next();
query.setParameter(key, parameterMap.get(key));
}
return query;
}
protected boolean followWithWord(String s, String sub, int pos) {
int i = 0;
for (; (pos < s.length()) && (i < sub.length()); ++i) {
if (s.charAt(pos) != sub.charAt(i))
return false;
++pos;
}
if (i < sub.length()) {
return false;
}
if (pos >= s.length()) {
return true;
}
return (!(isAlpha(s.charAt(pos))));
}
protected String parseSelectCount(String queryString) {
String hql = queryString.toLowerCase();
int noBlankStart = 0;
for (int len = hql.length(); noBlankStart < len; ++noBlankStart) {
if (hql.charAt(noBlankStart) > ' ') {
break;
}
}
int pair = 0;
if (!(followWithWord(hql, "select", noBlankStart))) {
pair = 1;
}
int fromPos = -1;
for (int i = noBlankStart; i < hql.length();) {
if (followWithWord(hql, "select", i)) {
++pair;
i += "select".length();
} else if (followWithWord(hql, "from", i)) {
--pair;
if (pair == 0) {
fromPos = i;
break;
}
i += "from".length();
} else {
++i;
}
}
if (fromPos == -1) {
throw new IllegalArgumentException("parse count sql error, check your sql/hql");
}
String countHql = "select count(*) " + queryString.substring(fromPos);
return countHql;
}
protected boolean isAlpha(char c) {
return ((c == '_') || (('0' <= c) && (c <= '9')) || (('a' <= c) && (c <= 'z')) || (('A' <= c) && (c <= 'Z')));
}
public void deleteById(Serializable id) {
T entity = getById(id);
delete(entity);
}
public void delete(List<T> entitys) {
for (T entity : entitys) {
delete(entity);
}
}
public T getById(Serializable id) {
if (id == null)
return null;
return (T) get(entityClazz, id);
}
@Override
public T saveEntity(T o) {
saveOrUpdate(o);
return o;
}
@Override
public void save(List<T> list) {
saveOrUpdateAll(list);
}
@Override
public T insert(T entity) {
save(entity);
return entity;
}
@Override
public void insert(List<T> entitys) {
for (T entity : entitys) {
save(entity);
}
}
@Override
public void update(List<T> entitys) {
for (T entity : entitys) {
update(entity);
}
}
@Override
public List<T> findByProperty(String name, Object value) {
String hql = "from " + entityClazz.getSimpleName() + " where " + name + "=? ";
return findList(hql, value);
}
@Override
public List<T> findByProperty(Map<String, Object> conditionMap) {
StringBuilder hql = new StringBuilder();
hql.append("from " + entityClazz.getSimpleName());
if (!conditionMap.isEmpty()) {
Iterator<String> it = conditionMap.keySet().iterator();
String key = it.next();
hql.append(" where " + key + "=:" + key);
while (it.hasNext()) {
key = it.next();
hql.append(" and " + key + "=:" + key);
}
}
return findList(hql.toString(), conditionMap);
}
@Override
public <V> List<V> findListByMax(final CharSequence queryString, final int maxResults, final Object... params) {
@SuppressWarnings({ "unchecked", "serial" })
List<V> list = (List<V>) executeQuery(new HibernateHandler() {
@Override
public List<V> doInHibernate(Session paramSession) {
try {
Query query = paramSession.createQuery(queryString.toString());
for (int i = 0; i < params.length; ++i) {
query.setParameter(i, params[i]);
}
return query.setMaxResults(maxResults).list();
} catch (RuntimeException re) {
throw re;
}
}
});
return list;
}
@Override
public <V> List<V> findListByMax(final CharSequence queryString, final int maxResults,
final Map<String, Object> params) {
@SuppressWarnings({ "unchecked", "serial" })
List<V> list = (List<V>) executeQuery(new HibernateHandler() {
@Override
public List<V> doInHibernate(Session paramSession) {
try {
Query query = paramSession.createQuery(queryString.toString());
for (Iterator<String> iterator = params.keySet().iterator(); iterator.hasNext();) {
String key = iterator.next();
query.setParameter(key, params.get(key));
}
return query.setMaxResults(maxResults).list();
} catch (RuntimeException re) {
throw re;
}
}
});
return list;
}
/**
* HQL/SQL之数据操作命令(DML)拼接辅助类
*
* @author PanJun
* @deprecated by fu.zhanghua
*
*/
public class DmlHelper {
private ThreadLocal<Calendar> cal = new ThreadLocal<Calendar>() {
@Override
protected Calendar initialValue() {
return Calendar.getInstance();
}
};
/** HQL/SQL参数 */
public final List<Object> paramList = new ArrayList<Object>();
/** HQL/SQL语句 */
public final StringBuilder dmlCmd = new StringBuilder();
public DmlHelper() {
}
public DmlHelper(CharSequence dml, Object... params) {
if (dml != null) {
dmlCmd.append(dml);
for (Object o : params) {
paramList.add(o);
}
}
}
@Override
public String toString() {
return "dml=" + dmlCmd + ", params=" + paramList;
}
public DmlHelper append(CharSequence dmlPart, Object... params) {
if (dmlPart != null) {
dmlCmd.append(" ").append(dmlPart);
for (Object o : params) {
paramList.add(o);
}
}
return this;
}
public DmlHelper addEqual(String fieldName, Object value, Object... nullVal) {
if (value == null || fieldName == null) {
return this;
}
if (value instanceof String) {
value = value.toString().trim();
if ("".equals(value)) {
return this;
}
}
for (Object NULL : nullVal) {
if (NULL == value) {
return this;
}
if (value.equals(NULL)) {
return this;
}
}
dmlCmd.append(" and ").append(fieldName).append("=? ");
paramList.add(value);
return this;
}
public DmlHelper addLikeAll(String name, String value) {
if (null == value || null == name)
return this;
value = "%" + value.trim().toLowerCase() + "%";
dmlCmd.append(" and lower(").append(name).append(") like ? ");
paramList.add(value);
return this;
}
/**
* 清除时间里的时分秒，只留日期
*
* @param date
* @return new date
*/
private void clearTime(Calendar calendar) {
int y = calendar.get(Calendar.YEAR);
int m = calendar.get(Calendar.MONTH);
int d = calendar.get(Calendar.DAY_OF_MONTH);
calendar.clear();
calendar.set(Calendar.YEAR, y);
calendar.set(Calendar.MONTH, m);
calendar.set(Calendar.DAY_OF_MONTH, d);
}
/**
* 添加开始日期、结束日期(注意时分秒不记入查询条件)查询条件，包含开始日期和结束日期
*
* @param fieldName
* hbm对象属性名称或字段名
* @param minDay
* 开始日期
* @param maxDay
* 结果日期
*/
public DmlHelper addDayRange(String fieldName, Date minDay, Date maxDay) {
Calendar calendar = cal.get();
if (minDay != null) {
calendar.setTime(minDay);
clearTime(calendar);
calendar.add(Calendar.SECOND, -1);
dmlCmd.append(" and ").append(fieldName).append(">? ");
paramList.add(calendar.getTime());
}
if (maxDay != null) {
calendar.setTime(maxDay);
clearTime(calendar);
calendar.add(Calendar.DAY_OF_MONTH, 1);
dmlCmd.append(" and ").append(fieldName).append("<? ");
paramList.add(calendar.getTime());
}
return this;
}
/**
* 添加开始时间、结束时间查询条件，包含开始时间和结束时间
*
* @param fieldName
* hbm对象属性名称或字段名
* @param minTime
* 开始时间
* @param maxTime
* 结果时间
*/
public DmlHelper addDayRange(String fieldName, String minTime, String maxTime) {
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
Date start_ = null, end_ = null;
if (ObjectUtil.hasText(minTime) && ObjectUtil.hasText(maxTime)) {
try {
start_ = sdf.parse(minTime);
end_ = sdf.parse(maxTime);
} catch (ParseException e) {
}
}
return addTimeRange(fieldName, start_, end_);
}
/**
* 添加开始时间、结束时间查询条件，包含开始时间和结束时间
*
* @param fieldName
* hbm对象属性名称或字段名
* @param minTime
* 开始时间
* @param maxTime
* 结果时间
*/
public DmlHelper addTimeRange(String fieldName, Date minTime, Date maxTime) {
if (minTime != null) {
dmlCmd.append(" and ").append(fieldName).append(">? ");
paramList.add(minTime);
}
if (maxTime != null) {
dmlCmd.append(" and ").append(fieldName).append("<? ");
paramList.add(maxTime);
}
return this;
}
public <D> Pagination<D> findPagin(int pageIndex, int pageSize) {
String hql = dmlCmd.toString();
Object[] allParams = new Object[paramList.size()];
int i = 0;
for (Object o : paramList) {
allParams[i++] = o;
}
return findPagination(hql, pageIndex, pageSize, allParams);
}
}
}工具类:
package com.zte.irobot.util;
import java.io.Serializable;
import java.util.List;
/**
* 数据分页类
*
*/
public class Pagination<T> implements Serializable {
private static final long serialVersionUID = -5884976706259160221L;
/**
* 上一页
*/
private long preIndex;
/**
* 当前页
*/
private long curIndex;
/**
* 下一页
*/
private long nextIndex;
/**
* 每页条数
*/
private long pageSize;
/**
* 总条数
*/
private long rowsCount;
//附加的
private int total;
public int getTotal() {
return total;
}
public void setTotal(int total) {
this.total = total;
}
public void setPreIndex(long preIndex) {
this.preIndex = preIndex;
}
public void setCurIndex(long curIndex) {
this.curIndex = curIndex;
}
public void setNextIndex(long nextIndex) {
this.nextIndex = nextIndex;
}
public void setPageSize(long pageSize) {
this.pageSize = pageSize;
}
/**
* 总页数
*/
private long pagesCount;
/**
* 对象列表
*/
private List<T> items;
/**
*
* 分页类构建函数
*
*/
public Pagination() {
updateInfo(0, 0, 0);
}
/**
*
* 分页类构建函数
*
* @param pageIndex
* 当前页码
* @param pageSize
* 每页记录数
*/
public Pagination(long pageIndex, long pageSize) {
updateInfo(pageIndex, pageSize, 0);
}
/**
* 分页类构建函数
*
* @param pageIndex
* 当前页码
* @param pageSize
* 每页记录数
* @param rowsCount
* 记录总数
*/
public Pagination(long pageIndex, long pageSize, long rowsCount) {
updateInfo(pageIndex, pageSize, rowsCount);
}
/**
* 获取当前面记录
*
* @return
*/
public List<T> getItems() {
return items;
}
/**
* 设置当前页记录
*
* @param items
*/
public void setItems(List<T> items) {
this.items = items;
}
/**
* 获取当前页码
*
* @return
*/
public long getCurIndex() {
return curIndex;
}
/**
* 获取下一页码
*
* @return
*/
public long getNextIndex() {
return nextIndex;
}
/**
* 获取总页数
*
* @return
*/
public long getPagesCount() {
return pagesCount;
}
/**
* 获取每页记录数
*
* @return
*/
public long getPageSize() {
return pageSize;
}
/**
* 获取上一页码
*
* @return
*/
public long getPreIndex() {
return preIndex;
}
/**
* 获取总记录数
*
* @return
*/
public long getRowsCount() {
return rowsCount;
}
/**
* 获取首页码
*
* @return
*/
public long getFirstIndex() {
return 1;
}
/**
* 获取末页码
*
* @return
*/
public long getLastIndex() {
return pagesCount;
}
private void updateInfo(long pageIndex, long pageSize, long rowsCount) {
if (pageSize > 0) {
this.curIndex = pageIndex;
this.rowsCount = rowsCount;
this.pageSize = pageSize;
// 确定页数
pagesCount = (rowsCount + pageSize - 1) / pageSize;
// 确定当前页码
if (curIndex <= 0)
curIndex = 1;
if (curIndex > pagesCount)
curIndex = pagesCount;
// 确定下一页码
nextIndex = curIndex + 1;
if (nextIndex > pagesCount)
nextIndex = pagesCount;
// 确定上一页码
preIndex = curIndex - 1;
if (preIndex <= 0)
preIndex = 1;
} else {
this.preIndex = 1;
this.curIndex = 1;
this.nextIndex = 1;
this.pageSize = 0;
this.pagesCount = 1;
}
}
/**
* 设置总记录数
*
* @param rowsCount
*/
public void setRowsCount(long rowsCount) {
updateInfo(curIndex, pageSize, rowsCount);
}
/**
* 设置总页数
*
* @param pagesCount
*/
public void setPagesCount(long pagesCount) {
this.pagesCount = pagesCount;
}
}
但是以上的代码只能查询单表的数据，后面项目很多功能需要多表进行关联查询，关联查询却不能用上面的代码进行分页，每次只能用Hibernate二级缓存区去查，所以，我利用上面的代码，封装了一个方法，使它能够进行多表关联查询。
封装的方法:
/**
* 多表关联查询分页
* @param query
* @param parameterMap
* @param pageIndex
* @param pageSize
* @return
*/
public static Pagination paginList(Query query, Map<String, Object> parameterMap,int pageIndex, int pageSize) {
for (@SuppressWarnings("rawtypes")
Iterator iterator = parameterMap.keySet().iterator(); iterator.hasNext();) {
String key = (String) iterator.next();
query.setParameter(key, parameterMap.get(key));
}
if ((pageSize > 0) && (pageIndex > 0)) {
query.setFirstResult((pageIndex < 2) ? 0 : (pageIndex - 1) * pageSize);
query.setMaxResults(pageSize);
}
int rowsCount = query.list().size();
Pagination pagination = new Pagination(pageIndex, pageSize, rowsCount);
pagination.setItems(query.list());
return pagination;
}在Dao层调用:
public Pagination<ChatHistory> getPaginList(StringBuffer hql, Map<String, Object> params, Integer pageIndex,
Integer pageSize) {
// TODO Auto-generated method stub
Query query = sessionFactory.getCurrentSession().createSQLQuery(hql.toString());
Pagination<ChatHistory> pagination = PagerFactory.paginList(query, params, pageIndex, pageSize);
return pagination;
}以上只是一个假分页，下面记录一下mysql真分页的计算:
//计算从第几条开始查
if (pageIndex == 1) {
pageIndex = 0;
}else {
pageIndex = pageIndex * pageSize - pageSize;
}
//计算返回前端的当前页
pageIndex==0?1:pageIndex / pageSize + 1
//总记录数
long rowsCount = query.list().size();
//总页数
long pagesCount = (rowsCount + pageSize - 1) / pageSize;
扫一扫
986
被折叠的 条评论
为什么被折叠?
到【灌水乐园】发言
