import java.io.IOException;
import java.io.InputStream;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.Properties;
import org.apache.log4j.Logger;
public class JdbcUtil {
private static Logger logger = Logger.getLogger(JdbcUtil.class);
private static JdbcUtil jdbcUtil;
private static String url = null;
private static String username = null;
private static String password = null;
private static String driver = null;
private static Properties props = new Properties();
static {
try { // 读取数据库配置文件
props.load(JdbcUtil.class.getResourceAsStream("/jdbc.properties"));
} catch (IOException e) {
logger.error(“加载jdbc.properties配置文件异常”, e);
}
url = (props.getProperty(“jdbc.url”));
username = (props.getProperty(“jdbc.username”));
password = (props.getProperty(“jdbc.password”));
driver = (props.getProperty(“jdbc.driver”));
// 加载数据库驱动
try {
Class.forName(driver);
} catch (ClassNotFoundException e) {
logger.error(“加载数据库驱动异常”, e);
}
} // 单例模式
public JdbcUtil getJdbcUtil() {
if (jdbcUtil == null) {
synchronized (JdbcUtil.class) {
if (jdbcUtil == null) {
jdbcUtil = new JdbcUtil();}
}
}
return jdbcUtil;
}
/**
* 创建一个数据库连接
* @return 一个数据库连接
*/
public Connection getConnection() {
Connection conn = null; // 创建数据库连接
try {
conn = DriverManager.getConnection(url, username, password);
} catch (SQLException e) {
logger.error(“创建数据库连接发生异常”, e);
}
return conn;} // 释放数据库资源
public void release(Object o) {
if (o == null) {
return;
}
if (o instanceof ResultSet) {
try {
((ResultSet) o).close();
} catch (SQLException e) {
e.printStackTrace();
}
} else if (o instanceof PreparedStatement) {
try {
((PreparedStatement) o).close();
} catch (SQLException e) {
e.printStackTrace();
}
} else if (o instanceof Connection) {
Connection c = (Connection) o;
try {
if (!c.isClosed()) {
c.close();
}
} catch (SQLException e) {
e.printStackTrace();
}
}
} // 释放数据库资源方法重载
public void release(ResultSet rs, PreparedStatement pst, Connection conn) {
release(rs);
release(pst);
release(conn);
}
}
如何数据库连接以及数据库资源释放
最新推荐文章于 2025-07-02 18:27:50 发布