Question

基本上我打算做的是从Agree1out文件中读取信息，其中包含以下信息：

1 | 1

2 | 0

以下代码链接到我的mySQL数据库，使用前两个数字（在“|”之前）获取xf.user.user_id。

目前字符串打印是：

equalsdavid 1 6af87ef8-e620-4d08-8320-183fc469eb0d

用户0 ac899bce-4a87-4977-957c-05013534b25b

我需要一种方法来删除字符串的第二部分小于1的行。现在我尝试做类似的事情，但既然我在这里你可能会告诉它不起作用：

  temp = temp.replaceAll("(?m)^0.*", "");

以下是代码：

  package io.chuchoter.stats2;

    import java.io.*;
    import java.sql.Connection;
    import java.sql.DriverManager;
    import java.sql.ResultSet;
    import java.sql.SQLException;
    import java.sql.Statement;
    import java.util.UUID;

    import io.chuchoter.core.Main;

    public class RATE2_agree {
    public static void main(String [] args) {

        String line = null;

        try {

            PrintStream p = new PrintStream(new File(Main.agree2out));
            System.setOut(p);

            FileReader fileReader = 
                new FileReader(Main.agree1out);

            BufferedReader bufferedReader = 
                new BufferedReader(fileReader);

            while((line = bufferedReader.readLine()) != null) {

                String[] parts = line.split("|");
                String part1 = parts[0];
                String part3 = parts[2];

                Connection con = DriverManager.getConnection(Main.host, Main.uName, Main.uPass);

                Statement rstmt = con.createStatement();
                String r = "SELECT * FROM `xf_user` WHERE `user_id` = " + part1 + ";";
                ResultSet rs = rstmt.executeQuery(r);

                while (rs.next()) {
                    String uuid = UUID.randomUUID().toString();
                    String username = rs.getString("username");

                    String print = username + " " + part3 + " " + uuid;
                    System.out.println(print);
                }
            }   

            bufferedReader.close();         

        }

        catch(FileNotFoundException ex) {
            System.out.println("Unable to open file");                
        }
        catch(IOException ex) {
            System.out.println(
                "Error reading file");
        }

        catch (SQLException err) {
            System.out.println(err.getMessage());
        }
    }

}

感谢您的帮助！

Answer 1

对于字符串“1 | 1”，当您应用分割

时

String[] parts = line.split("|");

你得到一个大小为2的数组。因此你的代码就像这样

String[] parts = line.split("|");
String part1 = parts[0];
String part3 = parts[1];         
Connection con = DriverManager.getConnection(Main.host, Main.uName, Main.uPass);

Statement rstmt = con.createStatement();
String r = "SELECT * FROM `xf_user` WHERE `user_id` = " + part1 + ";";
ResultSet rs = rstmt.executeQuery(r);

StringBuilder sb = new StringBuilder();
while (rs.next()) {
     String uuid = UUID.randomUUID().toString();
     String username = rs.getString("username");
     String print = username + " " + part3 + " " + uuid;
     if(Integer.parseInt(part3) >= 0)
         sb.append(print + "\n");
}
System.out.println(sb.toString());

希望这有帮助！

Java：不打印以某些字符开头的行

1 个答案: