application.properties
jdbc.driver=oracle.jdbc.driver.OracleDriver jdbc.url=jdbc:oracle:thin:@192.168.1.241:1521:orcl jdbc.username=im jdbc.password=im
ConnectionFactory.java
import java.beans.PropertyVetoException;
import java.sql.Connection;
import java.sql.SQLException;
import java.util.Map;
import com.mchange.v2.c3p0.ComboPooledDataSource;
import com.targsoft.webim.util.ReadProperties;
public class ConnectionFactory {
private ConnectionFactory(){
}
private static ComboPooledDataSource ds = null;
static {
try {
Map<String,String> map = new ReadProperties().readFile(Thread.currentThread().getContextClassLoader().getResource("").getPath()+"application.properties") ;
String driverName = map.get("jdbc.driver") ;
String dbURL = map.get("jdbc.url") ;
String userName = map.get("jdbc.username") ;
String userPwd = map.get("jdbc.password") ;
ds = new ComboPooledDataSource(); // 设置JDBC的Driver类
ds.setDriverClass(driverName); // 参数由 Config 类根据配置文件读取
ds.setJdbcUrl(dbURL); // 设置JDBC的URL
ds.setUser(userName); // 设置数据库的登录用户名
ds.setPassword(userPwd); // 设置数据库的登录用户密码
ds.setMaxPoolSize(200); // 设置连接池的最大连接数
ds.setMinPoolSize(20); // 设置连接池的最小连接数
} catch (PropertyVetoException e) {
e.printStackTrace();
}
}
public static synchronized Connection getConnection() {
Connection con = null;
try {
con = ds.getConnection();
} catch (SQLException e1) {
e1.printStackTrace();
}
return con;
}
}
TestCaseC3P0.java
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
public class TestCaseC3P0{
public static void main(String[] args) {
PreparedStatement pstmt = null; // 声明一个数据库操作对象
ResultSet rs = null; // 声明一个结果集对象
String sql = null; // 声明一个SQL变量,用于保存SQL语句
Connection con = null; // DataBaseConnection为具体的数据库连接及关闭操作类
con = ConnectionFactory.getConnection(); // 连接数据库
sql = "SELECT a.uuid FROM im_account a "; // 编写SQL语句
try {
pstmt = con.prepareStatement(sql);
rs = pstmt.executeQuery();
if (rs.next()) {
}
// 依次关闭
rs.close();
pstmt.close();
} catch (Exception e) {
System.out.println(e);
} finally {
// 最后一定要保证数据库已被关闭
try {
con.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}
}