C3P0连接池的使用

秒速五厘米 2022-06-09 11:22 236阅读 0赞

**需要导入的包如图所示：**

![Center][]

**并配置c3p0-config.xml文件：**

<?xml version="1.0" encoding="UTF-8"?>
    <c3p0-config>
    	
    	
    	<named-config name="oracle">
    		
    		<property name="driverClass">oracle.jdbc.driver.OracleDriver</property>
    		
    		<property name="jdbcUrl">jdbc:oracle:thin:@localhost:1521:orcl
    		</property>
    		
    		<property name="user">scott</property>
    		
    		<property name="password">tiger</property>
    		
    		<property name="maxPoolSize">100</property>
    		
    		<property name="minPoolSize">10</property>
    		
    		<property name="initialPoolSize">10</property>
    		
    		<property name="maxIdleTime">30</property>
    		
    		<property name="maxStatements">200</property>
    	</named-config>
    
    </c3p0-config>

**示例代码：**

package com.hcq.main;
    
    import java.sql.Connection;
    import java.sql.PreparedStatement;
    import java.sql.ResultSet;
    import java.sql.SQLException;
    
    import com.mchange.v2.c3p0.ComboPooledDataSource;
    
    public class Main {
    
    	public static void main(String[] args) {
    		try {
    			// 第一步：创建c3p0连接池
    			ComboPooledDataSource connPool = new ComboPooledDataSource("oracle");
    			// 第二步 ：从c3p0连接池中取出一个连接
    			Connection conn = connPool.getConnection();		
    			// 第三步：执行sql语句
    			PreparedStatement ps = conn.prepareStatement("SELECT empno,ename FROM emp");
    			ResultSet rs = ps.executeQuery();
    
    			while (rs.next()) {
    				int empno = rs.getInt(1);
    				String ename = rs.getString(2);
    				System.out.println("编号：" + empno + "\t姓名：" + ename);
    			}
    			// 第四步：释放连接将连接放回连接池
    			conn.close();
    			
    		} catch (SQLException e) {
    			e.printStackTrace();
    		} catch (InterruptedException e) {
    			e.printStackTrace();
    		}
    
    	}
    
    }

**截图：**

![Center 1][]

[Center]: /images/20220609/12de8ac45698460d9aecfd6d35d02522.png
[Center 1]: /images/20220609/99084f1cd78840e6b34061fef6f12e80.png