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package keel.util;

import java.sql.Connection;
import java.util.List;
import java.util.Map;

import org.apache.commons.dbutils.QueryRunner;
import org.apache.commons.dbutils.handlers.BeanListHandler;
import org.apache.commons.dbutils.handlers.MapHandler;
import org.apache.commons.dbutils.handlers.MapListHandler;
import org.apache.log4j.Logger;

/**
* 操作数据库方法
* @author 蔡治平
*
*/
public class SqlUtil {
private static Logger logger = Logger.getLogger(SqlUtil.class);
private static QueryRunner qr = new QueryRunner();

/**
* 查询
* @param conn
* @param sql
* @param params
* @return List<Map<String, Object>>
*/
@SuppressWarnings("deprecation")
public static List<Map<String, Object>> search(Connection conn, String sql, Object[] params){
List<Map<String, Object>> mapList = null;
try {
if(params==null){
mapList = qr.query(conn, sql, new MapListHandler());
}else{
mapList = qr.query(conn, sql, params, new MapListHandler());
}
} catch (Exception e) {
logger.error("查询出现异常!原因:"+e);
}
return mapList;
}

/**
* 查询,将结果返回到bean中,多个bean通过List包装返回
* @param <T>
* @param conn
* @param entityClass
* @param sql
* @param params
* @return List<T>
*/
@SuppressWarnings("unchecked")
public static <T>List<T> search(Connection conn, Class<T> entityClass, String sql, Object[] params){
List<T> list = null;
try{
if (params == null) {
list = (List<T>) qr.query(conn, sql, new BeanListHandler(entityClass));
} else {
list = (List<T>) qr.query(conn, sql, new BeanListHandler(entityClass), params);
}
}catch(Exception e){
logger.error("查询出现异常!原因:"+e);
}
return list;
}

/**
* 通过主键查找记录
* @param conn
* @param sql
* @param params
* @return Map<String, Object>
*/
public static Map<String, Object> getById(Connection conn, String sql, Object[] params){
Map<String, Object> map = null;
try{
if (params == null) {
map = qr.query(conn, sql, new MapHandler());
} else {
map = qr.query(conn, sql, new MapHandler(), params);
}
}catch (Exception e) {
logger.error("查询出现异常!原因:"+e);
}
return map;
}

/**
* 查询表的记录总数
* @param conn
* @param table
* @return int
*/
public static int getTotal(Connection conn, String table){
int total = 0;
String field = "TOTAL";
if(conn!=null){
String sql = "SELECT COUNT(*) AS "+field+" FROM "+table;
try {
Map<String, Object> map = (Map<String, Object>) qr.query(conn, sql, new MapHandler());
String n = map.get(field).toString();
total = Integer.parseInt(n);
} catch (Exception e) {
logger.error("查询["+table+"]表记录总数出现异常!原因:"+e);
}
}else{
logger.error("查询["+table+"]表记录总数出现异常!原因:连接为空!");
}
return total;
}

/**
* 更新,返回更新记录条数
* @param conn
* @param sql
* @param params
* @return int
*/
public static int update(Connection conn, String sql, Object[] params){
int n = 0;
try{
if(params==null){
n = qr.update(conn, sql);
}else{
n = qr.update(conn, sql, params);
}
}catch(Exception e){
logger.error("更新出现异常!原因:"+e);
}
return n;
}
}

List<Map<String, Object>> list = SqlUtil.search(conn, sql, new Object[]{"1001","admin"});
for(int i=0;i<list.size();i++){
System.out.println(list.get(i).get("id"));
System.out.println(list.get(i).get("userName"));
}

List<User> userList = SqlUtil.search(conn, User.class, sql, new Object[]{"1001","admin"});
for(int i=0;i<userList.size();i++){
System.out.println(userList.get(i).getId());
System.out.println(userList.get(i).getUserName());
}

String sql1 = "update rg_user set flag = 1 where id=?";
int n = SqlUtil.update(conn, sql1, new Object[]{"1001"});
System.out.println(n);

String sql2 = "select * from rg_user where id ='1001'";
Map<String,Object> map = SqlUtil.getById(conn, sql2, null);
System.out.println(map.get("id"));