1. Guide package
<dependency>
<groupId>org.apache.poi</groupId>
<artifactId>poi</artifactId>
<version>4.1.2</version>
</dependency>
<dependency>
<groupId>org.apache.poi</groupId>
<artifactId>poi-ooxml</artifactId>
<version>4.1.2</version>
</dependency>
<dependency>
<groupId>org.apache.poi</groupId>
<artifactId>poi-ooxml-schemas</artifactId>
<version>4.1.2</version>
</dependency>
2. Tools
package com.xxxx.xxxx.util;
import org.apache.poi.hssf.usermodel.*;
import org.apache.poi.ss.usermodel.BorderStyle;
import org.apache.poi.ss.usermodel.CellType;
import org.apache.poi.ss.usermodel.HorizontalAlignment;
import org.apache.poi.ss.util.CellRangeAddress;
import javax.servlet.http.HttpServletResponse;
import java.io.UnsupportedEncodingException;
import java.util.ArrayList;
import java.util.List;
/**
* 导出业务方法
*
* @author 955
* @since 2022/8/30 10:48
*/
public class ExportExcel {
/**
* 显示的导出表的标题
*/
private String title;
/**
* 导出表的列名
*/
private String[] rowName;
private List<List<?>> dataList = new ArrayList<List<?>>();
/**
* 构造函数，传入要导出的数据
*/
public ExportExcel(String title, String[] rowName, List<List<?>> dataList) {
this.dataList = dataList;
this.rowName = rowName;
this.title = title;
}
/**
* 列头单元格样式
*
* @param workbook
* @return
*/
public HSSFCellStyle getColumnTopStyle(HSSFWorkbook workbook) {
// 设置字体
HSSFFont font = workbook.createFont();
// 设置字体大小
font.setFontHeightInPoints((short) 15);
// 字体加粗
font.setBold(true);
// 设置字体名字
font.setFontName("Courier New");
// 设置样式
HSSFCellStyle style = workbook.createCellStyle();
// 设置低边框
style.setBorderBottom(BorderStyle.THIN);
// 设置右边框
style.setBorderRight(BorderStyle.THIN);
// 在样式中应用设置的字体
style.setFont(font);
// 设置自动换行
style.setWrapText(false);
// 设置水平对齐的样式为居中对齐；
style.setAlignment(HorizontalAlignment.CENTER);
style.setVerticalAlignment(style.getVerticalAlignmentEnum().CENTER);
return style;
}
/**
* @param workbook
* @return
*/
public HSSFCellStyle getStyle(HSSFWorkbook workbook) {
// 设置字体
HSSFFont font = workbook.createFont();
// 设置字体大小
font.setFontHeightInPoints((short) 10);
// 设置字体名字
font.setFontName("Courier New");
// 设置样式;
HSSFCellStyle style = workbook.createCellStyle();
// 设置底边框;
style.setBorderBottom(BorderStyle.THIN);
// 设置左边框;
style.setBorderLeft(BorderStyle.THIN);
// 设置右边框;
style.setBorderRight(BorderStyle.THIN);
// 设置顶边框;
style.setBorderTop(BorderStyle.THIN);
// 在样式用应用设置的字体;
style.setFont(font);
// 设置自动换行;
style.setWrapText(false);
// 设置水平对齐的样式为居中对齐;
style.setAlignment(HorizontalAlignment.CENTER);
// 设置垂直对齐的样式为居中对齐;
style.setVerticalAlignment(style.getVerticalAlignmentEnum().CENTER);
return style;
}
/**
* 发送响应流方法
*
* @param response 响应头
* @param fileName 文件名
*/
public static void setResponseHeader(HttpServletResponse response, String fileName) {
try {
try {
fileName = new String(fileName.getBytes(), "ISO8859-1");
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
response.setContentType("application/octet-stream;charset=ISO8859-1");
response.setHeader("Content-Disposition", "attachment;filename=" + fileName);
response.addHeader("Pargam", "no-cache");
response.addHeader("Cache-Control", "no-cache");
} catch (Exception ex) {
ex.printStackTrace();
}
}
/**
* 导出数据
*
* @param response
* @param fileName
* @throws Exception
*/
public void export(HttpServletResponse response, String fileName) {
try {
HSSFWorkbook workbook = new HSSFWorkbook();
HSSFSheet sheet = workbook.createSheet(title);
// 产生表格标题行
HSSFRow rowm = sheet.createRow(0);
HSSFCell cellTitle = rowm.createCell(0);
// sheet样式定义【】
HSSFCellStyle columnTopStyle = this.getColumnTopStyle(workbook);
HSSFCellStyle style = this.getStyle(workbook);
sheet.addMergedRegion(new CellRangeAddress(0, 1, 0, (rowName.length - 1)));
cellTitle.setCellStyle(columnTopStyle);
cellTitle.setCellValue(title);
// 定义所需列数
int columnNum = rowName.length;
HSSFRow rowRowName = sheet.createRow(2);
// 将列头设置到sheet的单元格中
for (int n = 0; n < columnNum; n++) {
HSSFCell cellRowName = rowRowName.createCell(n);
HSSFRichTextString text = new HSSFRichTextString(rowName[n]);
cellRowName.setCellValue(text);
cellRowName.setCellStyle(columnTopStyle);
}
// 将查询到的数据设置到sheet对应的单元格中
for (int i = 0; i < dataList.size(); i++) {
List<?> innerList = dataList.get(i);
// Object obj = dataList.get(i);// 遍历每个对象
// 创建所需的行数
HSSFRow row = sheet.createRow(i + 3);
for (int j = 0; j < innerList.size(); j++) {
HSSFCell cell = null;
Object obj = innerList.get(j);
if (j == 0) {
cell = row.createCell(j, CellType.STRING);
cell.setCellValue(i + 1);
} else {
cell = row.createCell(j, CellType.STRING);
cell.setCellValue(obj == null ? "" : obj.toString());
}
cell.setCellStyle(style);
}
}
// 让列宽随着导出的列长自动适应
for (int colNum = 0; colNum <= columnNum; colNum++) {
int columnWidth = sheet.getColumnWidth(colNum) / 256;
for (int rowNum = 0; rowNum <= sheet.getLastRowNum(); rowNum++) {
HSSFRow currentRow;
if (sheet.getRow(rowNum) == null) {
currentRow = sheet.createRow(rowNum);
} else {
currentRow = sheet.getRow(rowNum);
}
if (currentRow.getCell(colNum) != null) {
HSSFCell currentCell = currentRow.getCell(colNum);
if (currentCell.getCellType() == CellType.STRING) {
int length = 0;
length = currentCell.getStringCellValue().getBytes().length;
if (columnWidth < length) {
columnWidth = length;
}
}
}
}
if (colNum == 0) {
sheet.setColumnWidth(colNum, (columnWidth - 2) * 256);
} else {
sheet.setColumnWidth(colNum, (columnWidth + 4) * 256);
}
}
if (workbook != null) {
try {
setResponseHeader(response, fileName + ".xlsx");
workbook.write(response.getOutputStream());
} catch (Exception e) {
e.printStackTrace();
}
}
} catch (Exception e) {
e.printStackTrace();
}
}
}
3. Call
@Override
public void exportExcel(HttpServletResponse response) {
String[] ttt = new String[]{
"序号", "单位名称","测试标题"};
List<List<?>> rr = new ArrayList<>();
List<?> dataList = 方法名(参数);
for (? w : dataList) {
List<String> r = new ArrayList<>();
//注：空一行序号数据出来
r.add("");
r.add(w.getxxx() == null ? "" : w.getxxx());
r.add(w.getxxx() == null ? "" : w.getxxx());
rr.add(r);
}
ExportExcel e = new ExportExcel("导出数据", ttt, rr);
e.export(response, "导出数据");
}
4. Export effects
