java利用poi生成/读取excel表格、生成word

1.引入jar包依赖

　　　

<dependency>
            <groupId>org.apache.poi</groupId>
            <artifactId>poi</artifactId>
            <version>3.9</version>
        </dependency>

        <dependency>
            <groupId>org.apache.poi</groupId>
            <artifactId>poi-ooxml</artifactId>
            <version>3.8</version>
        </dependency>

2.编写代码测试

package testweb;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.util.LinkedList;
import java.util.List;

import org.apache.poi.hssf.usermodel.HSSFCell;
import org.apache.poi.hssf.usermodel.HSSFCellStyle;
import org.apache.poi.hssf.usermodel.HSSFFont;
import org.apache.poi.hssf.usermodel.HSSFRichTextString;
import org.apache.poi.hssf.usermodel.HSSFRow;
import org.apache.poi.hssf.usermodel.HSSFSheet;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.hssf.util.HSSFColor;


public class TestExcel {

    public static void main(String[] args) {
        List<Object> l=new LinkedList<>();
        l.add("zs");
        l.add("ls");
        l.add("we");
        l.add("mz");
        String[] headers=new String[]{"tou1","tou2","tou3","tou4"};
        try {
            OutputStream o= new FileOutputStream(new File("C:/Users/yanan/Desktop/yanantest.xls"));
            exportDataExcel("nihao",headers,l,o);
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        }
    }
    
    protected static void exportDataExcel(String title,String[] headers,List<Object> mapList,OutputStream out){  
        //声明一个工作簿  
        HSSFWorkbook workbook = new HSSFWorkbook();  
        //生成一个表格  
        HSSFSheet sheet = workbook.createSheet(title);  
        //设置表格默认列宽度字符  
        sheet.setDefaultColumnWidth(20);  
        //生成一个样式，用来设置标题样式  
        HSSFCellStyle style = workbook.createCellStyle();  
        //设置这些样式  
        style.setFillForegroundColor(HSSFColor.SKY_BLUE.index);  
        style.setFillPattern(HSSFCellStyle.SOLID_FOREGROUND);  
        style.setBorderBottom(HSSFCellStyle.BORDER_THIN);  
        style.setBorderLeft(HSSFCellStyle.BORDER_THIN);  
        style.setBorderRight(HSSFCellStyle.BORDER_THIN);  
        style.setBorderTop(HSSFCellStyle.BORDER_THIN);  
        style.setAlignment(HSSFCellStyle.ALIGN_CENTER);  
        //生成一个字体  
        HSSFFont font = workbook.createFont();  
        font.setColor(HSSFColor.VIOLET.index);  
        font.setBoldweight(HSSFFont.BOLDWEIGHT_BOLD);  
        //把字体应用到当前的样式  
        style.setFont(font);  
        // 生成并设置另一个样式,用于设置内容样式  
        HSSFCellStyle style2 = workbook.createCellStyle();  
        style2.setFillForegroundColor(HSSFColor.LIGHT_YELLOW.index);  
        style2.setFillPattern(HSSFCellStyle.SOLID_FOREGROUND);  
        style2.setBorderBottom(HSSFCellStyle.BORDER_THIN);  
        style2.setBorderLeft(HSSFCellStyle.BORDER_THIN);  
        style2.setBorderRight(HSSFCellStyle.BORDER_THIN);  
        style2.setBorderTop(HSSFCellStyle.BORDER_THIN);  
        style2.setAlignment(HSSFCellStyle.ALIGN_CENTER);  
        style2.setVerticalAlignment(HSSFCellStyle.VERTICAL_CENTER);  
        // 生成另一个字体  
        HSSFFont font2 = workbook.createFont();  
        font2.setBoldweight(HSSFFont.BOLDWEIGHT_NORMAL);  
        // 把字体应用到当前的样式  
        style2.setFont(font2);  
        //产生表格标题行  
        HSSFRow row = sheet.createRow(0);  
        for (int i = 0; i < headers.length; i++) {
            HSSFCell cell = row.createCell(i);
            cell.setCellStyle(style);
            HSSFRichTextString text = new HSSFRichTextString(headers[i]);
            cell.setCellValue(text);
        }
        for (int i = 0; i < mapList.size(); i++) {
            row = sheet.createRow(i + 1);
            int j = 0;
            HSSFCell cell = row.createCell(j++);
            cell.setCellValue("循环获得值1");
            cell.setCellStyle(style2);
            row.createCell(j++).setCellValue("循环获得值2");
            row.createCell(j++).setCellValue("循环获得值3");
            row.createCell(j++).setCellValue("循环获得值4");
        }
        try {
            workbook.write(out);
        } catch (IOException e) {
            e.printStackTrace();
        }
    } 
}

package testweb;

import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.text.DecimalFormat;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import org.apache.poi.hssf.usermodel.HSSFDateUtil;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.poifs.filesystem.POIFSFileSystem;
import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.ss.usermodel.Sheet;

public class TestExcel {
    public static void main(String[] args) {
        try {
            FileInputStream file = new FileInputStream("C:/Users/yanan/Desktop/yanan.xls");
            List<Map<String, Object>> yanantest = duquexcel(file);
            for (Map<String, Object> item : yanantest) {
                System.out.println(item.get("id") + "," + item.get("name") + "," + item.get("gendar")+","+item.get("time"));
            }
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        }
    }

    public static List<Map<String, Object>> duquexcel(InputStream fis) {
        List<Map<String, Object>> resultList = new ArrayList<Map<String, Object>>();
        HSSFWorkbook wb;
        try {
            wb = new HSSFWorkbook(new POIFSFileSystem(fis));
            Sheet sheet = wb.getSheetAt(0);
            // 日期格式化
            SimpleDateFormat sdf = new SimpleDateFormat("yyyy/M/dd");
            // 数字格式化
            DecimalFormat df = new DecimalFormat("##");
            // 循环xls中的每个表格
            Row firstRow = sheet.getRow(0);

            for (int i = sheet.getFirstRowNum() + 1; i <= sheet.getLastRowNum(); i++) {
                Row row = sheet.getRow(i);
                Map<String, Object> rowMap = new HashMap<String, Object>();

                for (int k = 0; k < row.getLastCellNum(); k++) {
                    Cell cell = row.getCell(k);
                    if (null == cell) {
                        continue;
                    }
                    switch (cell.getCellType()) {
                    case Cell.CELL_TYPE_NUMERIC:
                        if(HSSFDateUtil.isCellDateFormatted(cell)){
                            rowMap.put(firstRow.getCell(k).getStringCellValue(),sdf.format(HSSFDateUtil.getJavaDate(cell.getNumericCellValue())) );
                            break;
                        }
                        double value_d = cell.getNumericCellValue();
                        long value_l = (long) cell.getNumericCellValue();// cell.getCellStyle()获取样式
                        if (value_d == value_l)
                            rowMap.put(firstRow.getCell(k).getStringCellValue(), String.valueOf(value_l));
                        else
                            rowMap.put(firstRow.getCell(k).getStringCellValue(), String.valueOf(value_d));
                        break;
                    case Cell.CELL_TYPE_STRING:
                        rowMap.put(firstRow.getCell(k).getStringCellValue(), cell.getStringCellValue());
                        break;
                    case Cell.CELL_TYPE_BLANK:
                        break;
                    default:
                        rowMap.put(firstRow.getCell(k).getStringCellValue(), cell.toString());
                        break;
                    }
                }
                // 是否空行
                if (rowMap.size() > 0) {
                    resultList.add(rowMap);
                }
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
        return resultList;
    }
}

20200606之前的写法有些啰嗦，来个简单点的@参考博客，@官方文档，@参考地址3，@参考博客4

引入依赖

        <!-- https://mvnrepository.com/artifact/org.apache.poi/poi -->
        <dependency>
            <groupId>org.apache.poi</groupId>
            <artifactId>poi</artifactId>
            <version>4.1.2</version>
        </dependency>

代码：

        //得到Excel工作簿对象    
        HSSFWorkbook wb=new HSSFWorkbook ();
        //得到Excel工作表对象    
        HSSFSheet sheet =wb.createSheet("sheet名称");  
        //创建行
        HSSFRow row0 =sheet.createRow(0); 
        //创建单元格
        row0.createCell(0).setCellValue("单元格值");

POIFSFileSystem fs=newPOIFSFileSystem(new FileInputStream("d:/test.xls"));   
//得到Excel工作簿对象    
HSSFWorkbook wb = new HSSFWorkbook(fs);  
//得到Excel工作表对象    
HSSFSheet sheet = wb.getSheetAt(0);   
//得到Excel工作表的行    
HSSFRow row = sheet.getRow(i);  
//得到Excel工作表指定行的单元格    
HSSFCell cell = row.getCell((short) j);  
cellStyle = cell.getCellStyle();//得到单元格样式  

导出excel

        //application/octet-stream
        response.setCharacterEncoding("UTF-8");
　　　　　response.setContentType("application/vnd.ms-excel");//生成xls的
        response.setHeader("Content-Disposition", "attachment; filename=" + java.net.URLEncoder.encode("文件名称", "UTF-8")+".xls");  response.addHeader("Pargam", "no-cache");
        response.addHeader("Cache-Control", "no-cache");
        OutputStream os = response.getOutputStream();
        wb.write(os);
        os.flush();
        os.close();
　　　　 wb.close();

java.net.URLEncoder.encode("文件名称", "UTF-8")是为了防止文件名中文乱码
仅靠上述代码是文件有可能乱码，即便进行了如下设置（测试发现，这样写也是没起任何作用）

response.setContentType("application/ms-excel;charset=utf-8");

经验证，在controller中添加produces属性即可

@RequestMapping(value = { "/" }, produces =  "application/octet-stream")

如果需要生成xlsx格式的代码，需要调整一下。增加poi-ooxml依赖

        <!-- https://mvnrepository.com/artifact/org.apache.poi/poi -->
        <dependency>
            <groupId>org.apache.poi</groupId>
            <artifactId>poi</artifactId>
            <version>4.1.2</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/org.apache.poi/poi-ooxml -->
        <dependency>
            <groupId>org.apache.poi</groupId>
            <artifactId>poi-ooxml</artifactId>
            <version>4.1.2</version>
        </dependency>

更改相关类

@RequestMapping(value = { "/exportAnswerExcel2" }, method = {RequestMethod.GET },produces = "application/octet-stream")
@ResponseBody
public void exportAnswerExcel2(HttpServletRequest req,HttpServletResponse res) {

 　　　　 //得到Excel工作簿对象 

　　　　　　Workbook wb = new XSSFWorkbook();

　　　　　　//得到Excel工作表对象    

        Sheet sheet = wb.createSheet("工作簿名称");  
        //创建行
        Row row0 = sheet.createRow(0); 
        //创建单元格并赋值
        row0.createCell(0).setCellValue("单元格值");   
        res.setCharacterEncoding("UTF-8");
　　　　 response.setContentType("application/vnd.openxmlformats-officedocument.spreadsheetml.sheet");//生成xlsx的
        res.setHeader("Content-Disposition", "attachment; filename=" + java.net.URLEncoder.encode("excel文件名" "UTF-8")+".xlsx");  
        res.addHeader("Pargam", "no-cache");
        res.addHeader("Cache-Control", "no-cache");
        OutputStream os = res.getOutputStream();
    　 　wb.write(os);
   　　  os.flush();
        os.close();
        wb.close(); 
}        

区别是

new HSSFWorkbook ();是用来生成xls的，new XSSFWorkbook();是用来生成xlsx的

20200702：生成word，参考博客：

https://www.cnblogs.com/duanrantao/p/8682897.html

https://blog.csdn.net/zhouseawater/article/details/54289495

https://www.cnblogs.com/yfrs/p/wordpoi.html

https://blog.csdn.net/yinlei144/article/details/19316569

https://blog.csdn.net/weixin_43009990/article/details/89704258

java导出代码：

    public static void main(String[] args) throws IOException {
        XWPFDocument document= new XWPFDocument();
        //添加标题
        XWPFParagraph titleParagraph = document.createParagraph();
        //设置段落居中
        titleParagraph.setAlignment(ParagraphAlignment.CENTER);
    
        // 标题
        XWPFRun titleParagraphRun = titleParagraph.createRun();
        // 然后把你查出的数据插入到document中去就可以了
        titleParagraphRun.setText("AAA");
        // 设置字体颜色
        titleParagraphRun.setColor("000000");
        // 设置字体大小
        titleParagraphRun.setFontSize(15);
        titleParagraphRun.setFontFamily("宋体");
    
        //段落
        XWPFParagraph firstParagraph = document.createParagraph();
        XWPFRun run = firstParagraph.createRun();
        run.setText("BBB");
        run.setColor("000000");
        run.setFontSize(10);
        run.setText("	CCC☑○⊙");
        run.setColor("000000");
        run.setFontSize(12);
        //换行
        XWPFParagraph paragraph1 = document.createParagraph();
        XWPFRun paragraphRun1 = paragraph1.createRun();
        paragraphRun1.setText("
");
        paragraph1.setPageBreak(true);
        
        //段落
        XWPFParagraph firstParagraph2 = document.createParagraph();
        XWPFRun run2 = firstParagraph2.createRun();
        run2.setText("BBB");
        run2.setColor("000000");
        run2.setFontSize(10);
        run2.setText("	CCC☑");
        run2.setColor("000000");
        run2.setFontSize(12);
        
       
        OutputStream os =new FileOutputStream("D:/2.docx");
        document.write(os);
        os.flush();
        os.close();
        document.close();
    }

接口返回参考上面execl的改造一下就行了，不赘述了