JDBCUtils 工具类


这里写代码片
public final class JdbcUtil {
private static String DRIVER_CLASS = “com.mysql.jdbc.Driver”;
private static String URL=”jdbc:mysql:///bbs”; //bbs 数据库名
private static String USER = “root”; //mysql 账号
private static String PASSWORD = “123456”; mysql 密码
private static ThreadLocal threadLocal = new ThreadLocal<>();
static {
try {
Class.forName(DRIVER_CLASS);
} catch (ClassNotFoundException e) {
e.printStackTrace();
}
}
public static Connection getConnection() {

    try {
        return DriverManager.getConnection(URL, USER, PASSWORD);
    } catch (SQLException e) {
        e.printStackTrace();
    }

    return null;
}

public static void closeAll(ResultSet rs, Statement st, Connection conn) {
    try {
        if (rs != null)
            rs.close();
        if (st != null)
            st.close();
        if (conn != null)
            conn.close();
    } catch (SQLException e) {
        e.printStackTrace();
    } 
}
//**清除缓存，释放资源**
public static void closeResultSet(ResultSet rs) {
    try {
        if (rs != null)
            rs.close();
    } catch (SQLException e) {
        e.printStackTrace();
    } 
}
public static void closeStatement(Statement st) {
    try {
        if (st != null)
            st.close();
    } catch (SQLException e) {
        e.printStackTrace();
    } 
}
public static void closeConnection() {
    Connection conn = getConnection();
    if(conn != null) {
        try {
            conn.close();
        } catch (SQLException e) {
            e.printStackTrace();
        }
        threadLocal.remove();
    }
}