Java mysql连接

public List<String> getDBTable(String tableName) {
List<String> columns = new ArrayList<String>();
String driver = "com.mysql.jdbc.Driver";
String url = "jdbc:mysql://127.0.0.1:3306/sshdb";
try {
Class.forName(driver);
Connection conn = DriverManager.getConnection(url, "root", "");
Statement stm = conn.createStatement();
ResultSet rs = stm.executeQuery("show columns from " + tableName);
while(rs.next()) {
columns.add(rs.getString("Field"));
}
rs.close();
stm.close();
conn.close();
} catch (ClassNotFoundException e) {
e.printStackTrace();
} catch (SQLException e) {
e.printStackTrace();
}
return columns;
}