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我编写了一个 Java 程序来从 SQL 中获取数据并将其写入 Excel 表，以下程序仅在我取消注释我不知道为什么会这样的行时才有效，请帮助我更正程序。

 package com.selenium.examples;

import java.io.FileOutputStream;
import java.io.IOException;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.SQLException;
import java.sql.Statement;

import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.ss.usermodel.Sheet;
import org.apache.poi.ss.usermodel.Workbook;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;

public class SQLtoExcelSheet {

    public static void main(String[] args) throws SQLException, IOException {


        Workbook excel=new XSSFWorkbook();
        Sheet sheet= excel.createSheet("SQLResults");
        int excelRowNo=0;
        int excelCellNo=0;


        String connectionUrl = "jdbc:sqlserver://localhost;user=sa;password=abc@123";
        Connection con=DriverManager.getConnection(connectionUrl);

        Statement stmt=con.createStatement();

        String SQL="use BonusingCore;"+"select * from MachineMaster;";
        ResultSet result=stmt.executeQuery(SQL);
        ResultSetMetaData mataData=result.getMetaData();
        int columnCount=mataData.getColumnCount();
        result.next();

        //first row should be Column label
        for(int sqlColumnNumber=1;sqlColumnNumber<=columnCount;sqlColumnNumber++ ){
            Row excelRow=sheet.createRow(excelRowNo);
            Cell excelCell=excelRow.createCell(excelCellNo);
            excelCell.setCellValue(mataData.getColumnName(sqlColumnNumber));
            excelCellNo++;
            excelRowNo++;
            sheet.autoSizeColumn(excelCellNo);
        }
        FileOutputStream flout=new FileOutputStream("C:\\Users\\Illusion\\workspace\\SeleniumExamples\\testData\\output.xlsx");
        excel.write(flout);
        flout.close();
    }
}
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1 回答 1

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如果您想在任何特定行的某些列中写入一些数据，则需要createRow()一次且createCell()一直使用，如果它们都没有被初始化。

在代码中

 for(int sqlColumnNumber=1;sqlColumnNumber<=columnCount;sqlColumnNumber++ ){
          //creating a new row by createRow()... this will remove previous instance
        Row excelRow=sheet.createRow(excelRowNo);
          // creating a new column by createCell()
        Cell excelCell=excelRow.createCell(excelCellNo);
    ......

似乎对于每个单元格，您一次又一次地创建同一行，因此以前的数据会丢失。相反，您只需要创建一次行并使用同一行来创建所有单元格。

例如

         //creating a new row by createRow()
        Row excelRow=sheet.createRow(excelRowNo);

 for(int sqlColumnNumber=1;sqlColumnNumber<=columnCount;sqlColumnNumber++ ){
           // creating a new column by createCell()
        Cell excelCell=excelRow.createCell(excelCellNo);

希望你明白我想说什么......祝你好运..

于 2014-10-05T16:30:36.973 回答