MySQL——DBCP和C3P0连接池
DBPC：
需要用到的包：commons-dbcp2-2.10.0.jar，commons-pool2-2.12.0.jar，commons-logging-1.2.jar
实现：
新建文件dbcpconfig.properties
#连接设置
driverClassName=com.mysql.jdbc.Driver
url=jdbc:mysql://localhost:3306/jdbcstudy?useUnicode=true&characterEncoding=utf8&useSSL=true
username=root
password=123456
#
initialSize=10
#最大连接数量
maxActive=50
#
maxIdle=20
#
minIdle=5
#
maxWait=60000
#JDBC驱动建立连接时附带的连接属性属性的格式必须为这样：【属性名=property;】
#注意："user" 与 "password" 两个属性会被明确地传递，因此这里不需要包含他们。
connectionProperties=useUnicode=true;characterEncoding=UTF8
#指定由连接池所创建的连接的自动提交（auto-commit）状态。
defaultAutoCommit=true
#driver default 指定由连接池所创建的连接的只读（read-only）状态。
#如果没有设置该值，则“setReadOnly”方法将不被调用。（某些驱动并不支持只读模式，如：Informix）
defaultReadOnly=
#driver default 指定由连接池所创建的连接的事务级别（TransactionIsolation）。
#可用值为下列之一：（详情可见javadoc。）NONE,READ_UNCOMMITTED, READ_COMMITTED, REPEATABLE_READ, SERIALIZABLE
defaultTransactionIsolation=READ_UNCOMMITTED
工具类JdbcUtils_DPCP
package com.wen.lesson05.utils;
import org.apache.commons.dbcp2.BasicDataSource;
import org.apache.commons.dbcp2.BasicDataSourceFactory;
import javax.sql.DataSource;
import java.io.InputStream;
import java.sql.*;
import java.util.Properties;
public class JdbcUtils_DPCP {
private static DataSource dataSource = null;
static {
try{
InputStream in = JdbcUtils_DPCP.class.getClassLoader().getResourceAsStream("dbcpconfig.properties");
Properties properties = new Properties();
properties.load(in);
//创建数据源 工厂模式——> 创建对象
dataSource = BasicDataSourceFactory.createDataSource(properties);
} catch (Exception e) {
e.printStackTrace();
}
}
//获取连接
public static Connection getConnection() throws SQLException {
return dataSource.getConnection(); //从数据源中获取连接
}
//释放链接资源
public static void release(Connection conn, Statement st, ResultSet rs){
if (rs!=null){
try {
rs.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
if (st!=null){
try {
st.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
if (conn!=null){
try {
conn.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}
}
使用DBPC插入数据
package com.wen.lesson05;
import com.wen.lesson02.utils.JdbcUtils;
import com.wen.lesson05.utils.JdbcUtils_DPCP;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.Date;
public class TestDBCP {
public static void main(String[] args) {
Connection conn = null;
PreparedStatement st = null;
ResultSet rs = null;
try {
conn = JdbcUtils_DPCP.getConnection();
//区别
//使用？占位符代替参数
String sql = "INSERT INTO users(`id`,`NAME`,`PASSWORD`,`email`,`birthday`) VALUES(?,?,?,?,?)";
st = conn.prepareStatement(sql); //预编译sql，先写sql，然后不执行
//手动给参数赋值
st.setInt(1,4); //id
st.setString(2, "xiaoming"); //name
st.setString(3, "123456"); //password
st.setString(4, "[email protected]"); //email
//注意点： sql.Date 数据库 java.sql.Date
// util.Date Java new Date().getTime() 获得时间戳
st.setDate(5, new java.sql.Date(new Date().getTime())); //birthday
int i = st.executeUpdate();
if (i>0){
System.out.println("插入成功");
}
} catch (SQLException e) {
throw new RuntimeException(e);
} finally {
JdbcUtils_DPCP.release(conn, st, rs);
}
}
}
C3P0
需要用到的包：c3p0-0.9.5.5.jar，mchange-commons-java-0.2.20.jar
实现：
新建文件c3p0-config.xml
<c3p0-config>
<default-config>
<property name="driverClass">com.mysql.cj.jdbc.Driverproperty>
<property name="jdbcUrl">jdbc:mysql://localhost:3306/jdbcstudy?userUnicode=true&characterEncoding=utf8&useSSL=falseproperty>
<property name="user">rootproperty>
<property name="password">123456property>
<property name="acquiredIncrement">5property>
<property name="initialPoolSize">10property>
<property name="minPoolSize">5property>
<property name="maxPoolSize">20property>
default-config>
<named-config name="MySQL">
<property name="driverClass">com.mysql.jdbc.Driverproperty>
<property name="jdbcUrl">jdbc:mysql://localhost:3306/jdbcstudy?userUnicode=true&characterEncoding=utf8&useSSL=falseproperty>
<property name="user">rootproperty>
<property name="password">123456property>
<property name="acquiredIncrement">5property>
<property name="initialPoolSize">10property>
<property name="minPoolSize">5property>
<property name="maxPoolSize">20property>
named-config>
c3p0-config>
工具类JdbcUtils_C3P0
package com.wen.lesson05.utils;
import com.mchange.v2.c3p0.ComboPooledDataSource;
import org.apache.commons.dbcp2.BasicDataSourceFactory;
import javax.sql.CommonDataSource;
import javax.sql.DataSource;
import java.io.InputStream;
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Properties;
public class JdbcUtils_C3P0 {
private static ComboPooledDataSource dataSource = null;
static {
try{
//代码配置写法
//dataSource = new ComboPooledDataSource();
//dataSource.setDriverClass();
//dataSource.setUser();
//dataSource.setPassword();
//dataSource.setJdbcUrl();
//dataSource.setMaxPoolSize();
//dataSource.setMinPoolSize();
//创建数据源 工厂模式——> 创建对象
dataSource = new ComboPooledDataSource("MySQL"); //配置文件写法
} catch (Exception e) {
e.printStackTrace();
}
}
//获取连接
public static Connection getConnection() throws SQLException {
return dataSource.getConnection(); //从数据源中获取连接
}
//释放链接资源
public static void release(Connection conn, Statement st, ResultSet rs){
if (rs!=null){
try {
rs.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
if (st!=null){
try {
st.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
if (conn!=null){
try {
conn.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}
}
使用C3P0实现插入数据
package com.wen.lesson05;
import com.wen.lesson05.utils.JdbcUtils_C3P0;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.Date;
public class TestC3P0 {
public static void main(String[] args) {
Connection conn = null;
PreparedStatement st = null;
ResultSet rs = null;
try {
conn = JdbcUtils_C3P0.getConnection();
//区别
//使用？占位符代替参数
String sql = "INSERT INTO users(`id`,`NAME`,`PASSWORD`,`email`,`birthday`) VALUES(?,?,?,?,?)";
st = conn.prepareStatement(sql); //预编译sql，先写sql，然后不执行
//手动给参数赋值
st.setInt(1,5); //id
st.setString(2, "xiaohong"); //name
st.setString(3, "123456"); //password
st.setString(4, "[email protected]"); //email
//注意点： sql.Date 数据库 java.sql.Date
// util.Date Java new Date().getTime() 获得时间戳
st.setDate(5, new java.sql.Date(new Date().getTime())); //birthday
int i = st.executeUpdate();
if (i>0){
System.out.println("插入成功");
}
} catch (SQLException e) {
throw new RuntimeException(e);
} finally {
JdbcUtils_C3P0.release(conn, st, rs);
}
}
}