在Java中使用MySql

示例代碼如下：

import java.io.*;
import java.sql.*;
import java.util.Objects;

class DataReader {
    File dataSource=new File("/home/kisetsu/Documents/test_nsrxx");

    void readData() {

        //聲明Connection對象
        Connection con;
        //驅動程序名
        String driver = "com.mysql.jdbc.Driver";
        //URL指向要訪問的數據庫名mydata
        String url = "jdbc:mysql://localhost:3306/invoice";
        //MySQL配置時的用戶名
        String user = "root";
        //MySQL配置時的密碼
        String password = "5702";
        //遍歷查詢結果集

        FileInputStream fis = null;
        InputStreamReader isr = null;
        BufferedReader br = null; //用於包裝InputStreamReader,提高處理性能。因為BufferedReader有緩沖的，而InputStreamReader沒有。
        try {
            Class.forName(driver);
            //getConnection()方法，連接MySQL數據庫
            con = DriverManager.getConnection(url, user, password);
            if (!con.isClosed())
                System.out.println("Succeeded connecting to the Database!");
            //創建statement類對象，用來執行SQL語句
            Statement statement = con.createStatement();

            String str = "";
            String str1 = "";
            fis = new FileInputStream("/home/kisetsu/Documents/test_fpxx");// FileInputStream
            // 從文件系統中的某個文件中獲取字節
            isr = new InputStreamReader(fis);// InputStreamReader 是字節流通向字符流的橋梁,
            br = new BufferedReader(isr);// 從字符輸入流中讀取文件中的內容,封裝了一個new InputStreamReader的對象
            int count=0;
            double errorCount=0;
            long start=System.currentTimeMillis();
            //624087
            while ((str = br.readLine()) != null) {
                String[] infomation=str.split(",");

                count++;
                if(count<274850){
                    continue;
                }
                if(count%100==0){
                    System.out.println(count/100+"");
                    System.out.println(errorCount/(double) count+"");
                }
//                System.out.println("");
                for (int i=0;i<infomation.length;i++) {
                        if(Objects.equals(infomation[i], "null")){
                            infomation[i]="-1";
                        }
                }
                PreparedStatement psql;
                ResultSet res;
                psql = con.prepareStatement("insert into fpxx " +
                        "(xh,fp_nid,gfxbh,xfsbh,je,se,ze,kpyf,kprq,zfbz) " +
                        "values(?,?,?,?,?,?,?,?,?,?)");
//                try {
                    int len=infomation.length;
//                for (String s:infomation) {
//                    System.out.println(s);
//                }
                    psql.setInt(1,count);
                    psql.setString(2,infomation[0].substring(1));
                    psql.setString(3,infomation[1]);
                    psql.setString(4,infomation[2]);
//                    psql.setString(5,infomation[3]);
//                    psql.setString(6,infomation[4]);
//                    psql.setDouble(4,Double.parseDouble(infomation[infomation.length-5]));
//                    psql.setDouble(5,Double.parseDouble(infomation[infomation.length-4]));
                    psql.setDouble(5,Double.parseDouble(infomation[3]));
                    psql.setDouble(6,Double.parseDouble(infomation[4]));
                    psql.setDouble(7,Double.parseDouble(infomation[5]));
                    psql.setInt(8,Integer.parseInt(infomation[6]));
                    psql.setString(9,infomation[7]);
                    psql.setString(10,infomation[8].charAt(0)+"");
                    psql.executeUpdate();   //執行更新
//                }catch (Exception e){
//                    errorCount++;
//                    System.out.println("第"+count+"條數據出現錯誤");
//                    System.out.println("-------------------");
//                    System.out.println(count+"   ----   "+str);
//                }
//                if(count>500){
//                    break;
//                }
            }
            long end=System.currentTimeMillis();
            System.out.println(end-start);
            con.close();
            // 當讀取的一行不為空時,把讀到的str的值賦給str1// 打印出str1
        } catch (FileNotFoundException e) {
            System.out.println("找不到指定文件");
        } catch (IOException e) {
            System.out.println("讀取文件失敗");
        } catch (ClassNotFoundException | SQLException e) {
            e.printStackTrace();
        } finally {
            try {
                br.close();
                isr.close();
                fis.close();
                // 關閉的時候最好按照先后順序關閉最后開的先關閉所以先關s,再關n,最后關m
            } catch (IOException | NullPointerException e) {
                e.printStackTrace();
            }
        }
    }
}