mysql数据库连接池

Mysql连接池

下面是帮助类，类名：BaseBao

package org.shopping.dao;

import java.io.IOException;

import java.io.InputStream;

import https://www.360docs.net/doc/6e7811222.html,ng.reflect.Field;

import https://www.360docs.net/doc/6e7811222.html,ng.reflect.Method;

import java.sql.Connection;

import java.sql.PreparedStatement;

import java.sql.ResultSet;

import java.sql.ResultSetMetaData;

import java.sql.SQLException;

import java.util.ArrayList;

import java.util.List;

import java.util.Properties;

import https://www.360docs.net/doc/6e7811222.html,mons.beanutils.ConvertUtils;

import https://www.360docs.net/doc/6e7811222.html,mons.dbcp.BasicDataSource;

public abstract class BaseDao {

protected Connection conn=null;

protected PreparedStatement prepar=null;

protected ResultSet rs =null;

private static String DRIVER = null;

private static String URL = null;

private static String USER_NAME = null;

private static String USER_PASSWORD = null;

private static int initialSize;

private static int maxactive;

private static int maxIdle;

private static int minIdle;

private static int maxWait;

private static BasicDataSource datasource = new BasicDataSource();

/***

* 加载连接和属性赋值

*/

static{

getProperties();

getDataSource();

}

/**

* 从配置文件中给读出数据属性赋值

*/

public static void getProperties(){

Properties pro = new Properties();

InputStream input = BaseDao.class.getResourceAsStream("/db.properties");

try {

//加载文件中的类容

pro.load(input);

DRIVER = pro.getProperty("driver");

URL = pro.getProperty("url");

USER_NAME =pro.getProperty("user_name");

USER_PASSWORD =pro.getProperty("user_password");

initialSize =Integer.parseInt(pro.getProperty("initialSize"));

maxactive = Integer.parseInt(pro.getProperty("maxactive"));

maxIdle = Integer.parseInt(pro.getProperty("maxIdle"));

minIdle = Integer.parseInt(pro.getProperty("minIdle"));

maxWait = Integer.parseInt(pro.getProperty("maxWait"));

} catch (IOException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}finally{

try {

input.close();

} catch (IOException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

}

}

/**

* 给配置文件设置属性

*/

public static void getDataSource(){

datasource.setDriverClassName(DRIVER);

datasource.setUrl(URL);

datasource.setUsername(USER_NAME);

datasource.setPassword(USER_PASSWORD);

//连接池初始大小

datasource.setInitialSize(initialSize);

//最大连接

datasource.setMaxActive(maxactive);

//最大空闲时间

datasource.setMaxIdle(maxIdle);

//最小空闲时间

datasource.setMinIdle(minIdle);

//最大得等待时间

datasource.setMaxWait(maxWait);

}

/**

* 得到数据库的连接

* @return

*/

public Connection getConnection(){

try {

if(conn==null){

conn = datasource.getConnection();

}

} catch (SQLException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

return conn;

}

/**

* 关闭

*/

public void closeAll(){

try {

if(rs!=null){rs.close();};

if(prepar!=null){prepar.close();};

if(conn!=null){conn.close();};

} catch (Exception e) {

e.getMessage();

}finally{

this.prepar=null;

this.conn=null;

this.rs=null;

}

}

/**

* 查询

* @param sql

* @param params

* @return

*/

public List query(String sql,Object[] params,Class clas){

List lists = new ArrayList();

try {

prepar = this.getConnection().prepareStatement(sql) ;

if(params!=null&¶ms.length>0){

for(int i=0;i

prepar.setObject(i+1, params[i]);

}

}

rs = prepar.executeQuery();

ResultSetMetaData rsmt = rs.getMetaData();

while(rs.next()){

Object obj = clas.newInstance();

for( int i=0;i

String propertyName = rsmt.getColumnName(i+1);//属性名

Field field = clas.getDeclaredField(propertyName);

String mothedName ="set"+ propertyName.substring(0,1).toUpperCase()+propertyName.substring(1);

Method method = clas.getDeclaredMethod(mothedName, field.getType());

method.invoke(obj,ConvertUtils.convert(rs.getObject(i+1),field.getType()));

}

lists.add(obj);

}

} catch (Exception e) {

// TODO Auto-generated catch block

e.printStackTrace();

}finally{

this.closeAll();

}

return lists ;

}

/**

* 实现增删改

* @param sql

* @param params

* @return

*/

public int excuUpdate(String sql,Object[] params){

int row = 0;

try {

prepar = this.getConnection().prepareStatement(sql);

if(params!=null&¶ms.length>0){

for(int i=0;i

prepar.setObject(i+1, params[i]);

}

}

row = prepar.executeUpdate();

} catch (SQLException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}finally{

this.closeAll();

}

return row ;

}

}

导入类型转化包commons-beanutils-1.8.0.jar

下面是资源文件里面写的

名字：db.properties

内容：driver=com.mysql.jdbc.Driver

url=jdbc:mysql://localhost:3306/product_shopping

user_name=root

user_password=root

initialSize=5

maxactive=10

maxIdle=5

minIdle=0

maxWait=1000

创建在更目录下面