Druid鏈接池配置(java無框架)

鏈接池是一個對數據庫鏈接進行管理的東西，當一個線程須要用 JDBC 對 數據庫操做時，它從池中請求一個鏈接。當這個線程使用完了這個鏈接，將它返回到鏈接池中，這樣這就能夠被其它想使用它的線程使用，而不是每次都從新創建一個數據庫鏈接。

1.下載好Druid的jar包,並在項目中引入

2.在項目resource文件夾下面新建文件db_server.properties(druid配置文件)，複製以下內容:

driverClassName=com.mysql.jdbc.Driver
url=jdbc:mysql://127.0.0.1:3306/test?characterEncoding=utf-8
username=root
password=123456
filters=stat
initialSize=2
maxActive=300
maxWait=60000
timeBetweenEvictionRunsMillis=60000
minEvictableIdleTimeMillis=300000
validationQuery=SELECT 1
testWhileIdle=true
testOnBorrow=false
testOnReturn=false
poolPreparedStatements=false
maxPoolPreparedStatementPerConnectionSize=200

3.寫鏈接池管理工具類DBPoolConnection.java(配置文件db_server.properties所在路徑本身根據實際狀況填寫)

package com.cqgs.kit;

import java.io.File;
import java.io.FileInputStream;
import java.io.InputStream;
import java.sql.SQLException;
import java.util.Properties;

import org.apache.log4j.Logger;

import com.alibaba.druid.pool.DruidDataSource;
import com.alibaba.druid.pool.DruidDataSourceFactory;
import com.alibaba.druid.pool.DruidPooledConnection;

/**
* 要實現單例模式，保證全局只有一個數據庫鏈接池
*/
public class DBPoolConnection {
static Logger log = Logger.getLogger(DBPoolConnection.class);
private static DBPoolConnection dbPoolConnection = null;
private static DruidDataSource druidDataSource = null;

static {
Properties properties = loadPropertiesFile("resource/db_server.properties");
try {
druidDataSource = (DruidDataSource)DruidDataSourceFactory.createDataSource(properties); //DruidDataSrouce工廠模式
} catch (Exception e) {
log.error("獲取配置失敗");
}
}

/**
* 數據庫鏈接池單例
* @return
*/
public static synchronized DBPoolConnection getInstance(){
if (null == dbPoolConnection){
dbPoolConnection = new DBPoolConnection();
}
return dbPoolConnection;
}

/**
* 返回druid數據庫鏈接
* @return
* @throws SQLException
*/
public DruidPooledConnection getConnection() throws SQLException{
return druidDataSource.getConnection();
}
/**
* @param string 配置文件名
* @return Properties對象
*/
private static Properties loadPropertiesFile(String fullFile) {
String webRootPath = null;
if (null == fullFile || fullFile.equals("")){
throw new IllegalArgumentException("Properties file path can not be null" + fullFile);
}
webRootPath = DBPoolConnection.class.getClassLoader().getResource("").getPath();
webRootPath = new File(webRootPath).getParent();
InputStream inputStream = null;
Properties p =null;
try {
inputStream = new FileInputStream(new File(webRootPath + File.separator + fullFile));
p = new Properties();
p.load(inputStream);
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
if (null != inputStream){
inputStream.close();
}
} catch (Exception e) {
e.printStackTrace();
}
}

return p;
}

}

4.如何使用鏈接池得到鏈接，回收鏈接

 

 最後記得把鏈接放回鏈接池