Question

在这里，我想从MySQL DB＆amp;获取数据。运行play方法。但它立即执行。我希望得到第一行信息传递给ply方法＆amp;得到第二行信息＆amp;将它传递给play方法等等。请帮我解决这个问题。提前谢谢你。

public class Player {

static Play PL = new Play();

public static void main(String[] args) {

    try {

        Statement stmt = null;
        // connect to database radio
        Connection conn = DriverManager.getConnection("jdbc:mysql://localhost/radio", "root", "");
        stmt=conn.createStatement();

            String sql = "SELECT Link FROM split";
            ResultSet rs = stmt.executeQuery(sql);
            //STEP 5: Extract data from result set
                while(rs.next()){
                    //Retrieve by column name

                    int numColumns = rs.getMetaData().getColumnCount();

                    for ( int i = 1 ; i <= numColumns ; i++ ) {

                        System.out.println(numColumns);
                        String SongLocation = rs.getString(i);

                    System.out.println(SongLocation);

                    PL.play(SongLocation);

                    System.out.println("playing song");   

                    }
          }

    } catch (SQLException e1) {

        e1.printStackTrace();
    }

}

}

Answer 1

我认为您使用

循环遍历列

int numColumns = rs.getMetaData().getColumnCount();
for ( int i = 1 ; i <= numColumns ; i++ ) {
 ...

而是尝试使用while循环

 while (rs.next()) {
 ...

因为你需要索引，所以包含一个局部变量int i，你只需要在每个while循环之后递增

使用java从MySQL DB中检索数据

1 个答案: