使用Apache Poi将结果集从Java数据库导出到Excel

Question

Help am stucked on this project of exporting from result set to excel..previous solutions here haven't answered my questions but they have helped..here is my code so far it only displays a row in the database. My Code

import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.logging.Level;
import java.util.logging.Logger;
import org.apache.poi.hssf.usermodel.HSSFSheet;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.ss.usermodel.*;


public class Plexada2 {


        public static void main(String[] args) {
        try {
        Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
         Connection conn = DriverManager.getConnection("jdbc:odbc:Storeway","root", "");
         Statement st = conn.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE, ResultSet.CONCUR_UPDATABLE);
         ResultSet rs = st.executeQuery("Select * from Storeway.order");

         HSSFWorkbook workbook = new HSSFWorkbook();
         HSSFSheet sheet = workbook.createSheet("lawix10");


         Row row = sheet.createRow(0);
         int x=0;
         while (rs.next()){
         String crate_id=  rs.getString(2);
         String content=rs.getString(3);
         String Order_type=  rs.getString(4);
         java.sql.Date date= rs.getDate(5);
         String datex= String.valueOf(date);

         row.createCell(0).setCellValue(crate_id);
         row.createCell(1).setCellValue(content);
         row.createCell(2).setCellValue(Order_type);
         row.createCell(3).setCellValue(datex); 

                }
         x+=1;  



        String yemi = "C:\\Users\\lawix10\\Desktop\\testlno9.xls";
        FileOutputStream fileOut;
        try {
             fileOut = new FileOutputStream(yemi);
             workbook.write(fileOut);
             fileOut.close();
                }

Answer 1

Ahh its very difficult to inspect your code trying formatting it before you post it and Regarding your query try something like this.

try {
    Class.forName("driverName");
    Connection con = DriverManager.getConnection("url", "user", "pass");
    Statement st = con.createStatement();
    ResultSet rs = st.executeQuery("Select * from tablename");
    HSSFWorkbook workbook = new HSSFWorkbook();
    HSSFSheet sheet = workbook.createSheet("lawix10");
    HSSFRow rowhead = sheet.createRow((short) 0);
    rowhead.createCell((short) 0).setCellValue("CellHeadName1");
    rowhead.createCell((short) 1).setCellValue("CellHeadName2");
    rowhead.createCell((short) 2).setCellValue("CellHeadName3");
    int i = 1;
    while (rs.next()){
        HSSFRow row = sheet.createRow((short) i);
        row.createCell((short) 0).setCellValue(Integer.toString(rs.getInt("column1")));
        row.createCell((short) 1).setCellValue(rs.getString("column2"));
        row.createCell((short) 2).setCellValue(rs.getString("column3"));
        i++;
    }
    String yemi = "g:/test.xls";
    FileOutputStream fileOut = new FileOutputStream(yemi);
    workbook.write(fileOut);
    fileOut.close();
    } catch (ClassNotFoundException e1) {
       e1.printStackTrace();
    } catch (SQLException e1) {
        e1.printStackTrace();
    } catch (FileNotFoundException e1) {
        e1.printStackTrace();
    } catch (IOException e1) {
        e1.printStackTrace();
    }

Answer 2

can we have for loop to enter dynamic values into getString()?I tried this, but i couldnt fetch exact result.

My code: public static void excel(String appDB) { List headerValues=new ArrayList();

    XSSFWorkbook workbook = new XSSFWorkbook();
    try {
    setConnection(appDB);

    String queryName="SELECT * FROM ALL_TABLES where table_name='table_name'";

    Reporter.addStepLog("----------------------------------- " + queryName.toUpperCase()
            + "\n - Validation Start" + " -----------------------------------");
    ps = con.prepareStatement(queryName, ResultSet.TYPE_SCROLL_INSENSITIVE, ResultSet.CONCUR_UPDATABLE);
    rs = ps.executeQuery();

    Statement statement = con.createStatement();
    XSSFSheet spreadsheet = workbook.createSheet("employedb");
      ResultSet resultSet = statement.executeQuery("select * from all_tab_columns where table_name='table_name'"); 
      XSSFRow row = spreadsheet.createRow(0);
      XSSFCell cell;
      int cc=resultSet.getMetaData().getColumnCount();
      for(int i=1;i<=cc;i++)
      {
          String headerVal=resultSet.getMetaData().getColumnName(i);
          headerValues.add(headerVal);
          cell = row.createCell(i-1);
          cell.setCellValue(resultSet.getMetaData().getColumnName(i));
      }
      System.out.println(headerValues);
      int i = 1;
      while (resultSet.next())
      {  
          for(int j=1;j<=cc;j++)
          {  
          System.out.println(resultSet.getString(j));
          XSSFRow row1 = spreadsheet.createRow((short) i);
          row1.createCell((short) i).setCellValue(resultSet.getString(resultSet.getMetaData().getColumnName(j)));
          i++;

      }  
      }

      FileOutputStream out = new FileOutputStream(new File("S:\\Downloads\\excel.xlsx"));
      workbook.write(out);
      out.close();  
      System.out.println("exceldatabase.xlsx written successfully");

}catch(Exception e){}
}

Answer 3

Above issue got resolved.

public static void excel(String appDB)
{
    List<String> headerValues=new ArrayList<String>();

    XSSFWorkbook workbook = new XSSFWorkbook();
    try {
    setConnection(appDB);

    String queryName="SELECT * FROM ALL_TABLES where table_name='table_name";

    Reporter.addStepLog("----------------------------------- " + queryName.toUpperCase()
            + "\n - Validation Start" + " -----------------------------------");
    ps = con.prepareStatement(queryName, ResultSet.TYPE_SCROLL_INSENSITIVE, ResultSet.CONCUR_UPDATABLE);
    rs = ps.executeQuery();

    Statement statement = con.createStatement();
    XSSFSheet spreadsheet = workbook.createSheet("employedb");
      ResultSet resultSet = statement.executeQuery("select * from all_tab_columns where table_name='table_name'");


      XSSFRow row = spreadsheet.createRow(0);
      XSSFCell cell;
      int cc=resultSet.getMetaData().getColumnCount();
      for(int i=1;i<=cc;i++)
      {
          String headerVal=resultSet.getMetaData().getColumnName(i);
          headerValues.add(headerVal);
          cell = row.createCell(i-1);
          cell.setCellValue(resultSet.getMetaData().getColumnName(i));
      }
      System.out.println(headerValues);

      int i = 1;
      while (resultSet.next())
      {  

          XSSFRow row1 = spreadsheet.createRow((short) i);
          for(int p=0;p<headerValues.size();p++)
          {
          row1.createCell((short) p).setCellValue(resultSet.getString(headerValues.get(p)));
          }
          i++;
      } 
      FileOutputStream out = new FileOutputStream(new File("S:\\Downloads\\excel.xlsx"));
      workbook.write(out);
      out.close();  
      System.out.println("exceldatabase.xlsx written successfully");

}catch(Exception e){}
}

Answer 4

I suggest another solution, taking advantage of MemPOI lib. Take a look:

public class Plexada2 {

    public static void main(String[] args) {
        try {
           Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
           Connection conn = DriverManager.getConnection("jdbc:odbc:Storeway","root", "");
           PreparedStatement prepStmt = conn.prepareStatement("Select * from Storeway.order");

           File fileDest = new File("C:\\Users\\lawix10\\Desktop\\testlno9.xls");

           new MempoiBuilder()
                .setFile(fileDest)
                .addMempoiSheet(new MempoiSheet(prepStmt))
                .build()
                .prepareMempoiReportToFile()
                .get();
         } catch (Exception e) {
            // TODO manage exception
         }
    }
}