Java c3po

1、准备通用类

（引用：c3p0-0.9.1.2.jar）

package nankang.test;

import java.sql.Connection;

import com.mchange.v2.c3p0.ComboPooledDataSource;

public class ConnectionFactory {

    private static ComboPooledDataSource ds = null;

    static {
        try {
            String driver = "oracle.jdbc.driver.OracleDriver";
            String url = "jdbc:oracle:thin:@127.0.0.1:1521:orcl";
            String user = "phonesurvey";
            String password = "world";

            ds = new ComboPooledDataSource();
            ds.setDriverClass(driver);
            ds.setJdbcUrl(url);
            ds.setUser(user);
            ds.setPassword(password);

            ds.setMaxPoolSize(200);
            ds.setMinPoolSize(20);

        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    public static synchronized Connection getConnection(){
        Connection conn = null;
        try{
            conn = ds.getConnection();
        }catch(Exception e){
            e.printStackTrace();
        }
        return conn;
    }

}

2、调用

package nankang.test;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;

public class Main {

    /**
     * @param args
     */
    public static void main(String[] args) {

        Connection conn = null;
        PreparedStatement pstm = null;
        ResultSet rs = null;

        try {
            conn = ConnectionFactory.getConnection();

            String sql = "select * from Agent";
            pstm = conn.prepareStatement(sql);
            rs = pstm.executeQuery();
            while (rs.next()) {
                String agentId = rs.getString("AgentId");

                System.out.println(agentId);
            }

            System.out.println("成功");
        } catch (Exception e) {
            System.out.println(String.format("失败，%s", e.getMessage()));
        } finally {
            if (rs != null) {
                try {
                    rs.close();
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
            if (pstm != null) {
                try {
                    pstm.close();
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
            if (conn != null) {
                try {
                    conn.close();
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        }
    }

}