JDBC executeUpdate（）仅插入1行

Question

My code reads data from a text file to populate a database. The text file contains 5 lines, including a blank line (line 4). The code reads the text file but only insert the last line in the database. I also need the code to skip reading the first line in the text file.

Any help where I have gone wrong? I am new to Java Programming.

Here is my code:

import java.io.*;
import java.sql.*;

public class Example {
   public static Connection getConnection() throws Exception {
        String driver = "org.apache.derby.jdbc.ClientDriver";
        String url = "jdbc:derby://localhost:1527/Orders";
        String username = "user";
        String password = "password";

        Class.forName(driver);
        Connection conn = DriverManager.getConnection(url, username, password);
        return conn;
   } 
   public static void main(String[] args)throws Exception {

       String id ="";
       String firstName ="";
       String lastName ="";
       String street="";
       String city ="";
       String fileName = "src/Person.data"; 
       String line = null;


       PreparedStatement pstmt = null;
       Connection conn = null;

       try {
           FileReader fileReader = 
           new FileReader(fileName);
           BufferedReader bufferedReader = 
           new BufferedReader(fileReader);  


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

               if ( line.trim().length() == 0 ) {
                   continue;  // Skip blank lines
               } 
               String[] splited = line.split(",");
               //System.out.println(line);
               id=splited[0];
               firstName=splited[1];
               lastName=splited[2];
               street=splited[3];
               city=splited[4];
               System.out.println(line);
               System.out.println(splited[4]);

               conn = getConnection();
               conn.setAutoCommit(false);

               pstmt = conn.prepareStatement("insert into APP.Person(PERSON_ID, LAST_NAME, FIRST_NAME,STREET,CITY)values (?,?,?,?,?)");     
               pstmt.setString(1, id);
               pstmt.setString(2, firstName);
               pstmt.setString(3, lastName);
               pstmt.setString(4, street);
               pstmt.setString(5, city);
               pstmt.executeUpdate();
               conn.commit();
           }   
           bufferedReader.close();     
       }
       catch(FileNotFoundException ex) {
           System.out.println(
                "Unable to open file '" + 
                fileName + "'");  
        ex.printStackTrace();
       }
       catch(IOException ex) {
            System.out.println(
                "Error reading file '" 
                + fileName + "'");                  
       }

   }   
}

Answer 1

This is due to insertion only gets executed for the last record. The better option is to use executebatch. first add all those insert scripts in batch and after completion of loop just execute that batch.

Prepared statement is created inside the loop which is wrong. You need to create a Prepared statement out of the loop.

Use try catch block as follow:

    try {
        FileReader fileReader =
                new FileReader(fileName);
        BufferedReader bufferedReader =
                new BufferedReader(fileReader);
        conn = getConnection();
            conn.setAutoCommit(false);

            pstmt = conn.prepareStatement("insert into APP.Person(PERSON_ID, LAST_NAME, FIRST_NAME,STREET,CITY)values (?,?,?,?,?)");

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

            if ( line.trim().length() == 0 ) {
                continue;  // Skip blank lines
            }
            String[] splited = line.split(",");
            //System.out.println(line);
            id=splited[0];
            firstName=splited[1];
            lastName=splited[2];
            street=splited[3];
            city=splited[4];
            System.out.println(line);
            System.out.println(splited[4]);


            pstmt.setString(1, id);
            pstmt.setString(2, firstName);
            pstmt.setString(3, lastName);
            pstmt.setString(4, street);
            pstmt.setString(5, city);
            pstmt.addBatch();

        }
        pstmt.executeBatch();
        conn.commit();
        bufferedReader.close();
    }
    catch(FileNotFoundException ex) {
        System.out.println(
                "Unable to open file '" +
                        fileName + "'");
        ex.printStackTrace();
    }
    catch(IOException ex) {
        System.out.println(
                "Error reading file '"
                        + fileName + "'");
    }