【保姆级】Java后端查询数据库结果导出xlsx文件+打印xlsx表格

前言

最近在弄一个需求，需求如下：
需求一：Vue前端点击导出按钮，就可以将从数据库查出的数据导出成xlsx，即Excel表格形式
需求二：点击打印按钮，要将生成的xlsx文件启动进程，调用打印接口，实现打印，这是为了生成客户订单表，可以让机器直接打印

PS：想吐槽网上很多都复制粘贴的技术文章，找半天一点卵用都没用，这里记录一下自己解决方案，若转发请注明出处，原创不易，有问题可评论区留言

需求一效果预览

需求二预览

一、需求一：数据库查询的数据导出成Excel表格

1.1 Vue前端实现导出按钮+点击事件

<el-button type="success" round icon="el-icon-download" @click="exportByEasyPoi">导出</el-button>

对应按钮点击触发的exportByEasyPoi方法，这里我用的是EasyPoi操作Excel，也挺多公司用的
注：前端是Vue2

<script>
import userApi from '@/api/userManage'
export default {methods: {exportByEasyPoi() {userApi.exportByEasyPoi().then(response => {this.$message.success('导出成功')})}}
}
</script>

这里我调用了src/api/userManage.js，这是自己创建的js脚本，调用后端接口的

import request from '@/utils/request'export default {exportByEasyPoi() {return request({url: `/user/exportep`,method: 'get',timeout: '10000'})}
}

需求一前端就这么多了，接下来就是后端

1.2 后端根据数据库查询结果生成xlsx文件

首先导入EasyPoi相关依赖

<!--easypoi-->
<dependency><groupId>cn.afterturn</groupId><artifactId>easypoi-spring-boot-starter</artifactId><version>4.3.0</version>
</dependency>
<dependency><groupId>cn.afterturn</groupId><artifactId>easypoi-base</artifactId><version>4.3.0</version>
</dependency>
<dependency><groupId>cn.afterturn</groupId><artifactId>easypoi-web</artifactId><version>4.3.0</version>
</dependency>
<dependency><groupId>cn.afterturn</groupId><artifactId>easypoi-annotation</artifactId><version>4.3.0</version>
</dependency>
<!-- lombok -->
<dependency><groupId>org.projectlombok</groupId><artifactId>lombok</artifactId><version>1.18.20</version>
</dependency>

下面先给出后端核心逻辑代码，后面会具体讲解，这里就不加篇幅，直接把逻辑代码写在Controller层，原本应该写在Service层，即xxxServiceImpl实现类中，这里为了方便，直接这么写下。

@Autowired
private IUserService userService;@GetMapping("/exportep")public Result<?> exportByEasyPoi(HttpServletResponse response) throws IOException {// mybatisplus实现的list()，拿到用户信息列表List<User> users = userService.list();List<ExcelUserVo> excelUserVos = BeanCopyUtils.copyBeanList(users, ExcelUserVo.class);// easypoi导出ExportParams params = new ExportParams();params.setTitle("测试");// 表格左下角的sheet名称params.setSheetName("用户信息");Workbook workbook = ExcelExportUtil.exportExcel(params, ExcelUserVo.class, excelUserVos);// 判断文件路径是否存在，并将信息写入文件try{// 文件夹是否存在，若没有对应文件夹直接根据路径生成文件会报错File folder = new File(Constants.XLSX_DIR);if (!folder.exists() && !folder.isDirectory()) {folder.mkdirs();}// 文件是否存在File file = new File(Constants.XLSX_DIR + "\\" + Constants.XLSX_NAME);if (!file.exists()){file.createNewFile();}// 输出流写入FileOutputStream outputStream = new FileOutputStream(Constants.XLSX_DIR + "\\" + Constants.XLSX_NAME);workbook.write(outputStream);// 关闭写，不然用户点击生成的文件会显示只读outputStream.close();workbook.close();}catch (IOException e){e.printStackTrace();}return Result.success("导出成功");}

ExcelUserVo.java是自己需要显示在表格中的列，就是我们查询用户表，大部分时候不需要展示所有的属性到前端，挑需要显示的，所以封装成xxxVo，比如密码、创建时间、备注可以不显示在前端，不用打印就不要。

import cn.afterturn.easypoi.excel.annotation.Excel;
import cn.afterturn.easypoi.excel.annotation.ExcelTarget;
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;import java.io.Serializable;@Data
@NoArgsConstructor
@AllArgsConstructor
@ExcelTarget("sys_user")
public class ExcelUserVo implements Serializable {@Excel(name = "用户id", width = 10)
//    @ExcelIgnore // 表示忽略, 不在表格生成private Integer id;@Excel(name = "用户名", width = 20)private String username;@Excel(name = "邮箱", width = 30)private String email;@Excel(name = "电话", width = 30)private String phone;@Excel(name = "状态（1:正常，0:禁用）", width = 10)private Integer status;
}

BeanCopyUtils.java是常用工具类，可以实现对象的拷贝，将两个对象中相同属性字段拷贝

import java.util.List;
import java.util.stream.Collectors;public class BeanCopyUtils {private BeanCopyUtils() {}/** 单个对象*/public static <V> V copyBean(Object source, Class<V> clazz) {/** 创建目标对象 实现属性拷贝*/V result = null;try {result = clazz.newInstance();/** 拷贝*/BeanUtils.copyProperties(source, result);} catch (Exception e) {e.printStackTrace();}return result;}/** 集合*/public static <O, V> List<V> copyBeanList(List<O> list, Class<V> clazz) {/** 创建目标对象 实现属性拷贝*/return list.stream().map(o -> copyBean(o, clazz)).collect(Collectors.toList());}
}

自定义常量Constants.java，这里主要是定义输出路径

public class Constants {// excel表public static final String XLSX_DIR = "D:\\study\\excel";public static final String XLSX_NAME = "easypoi.xlsx";}

数据库sys_user表结构

DROP TABLE IF EXISTS `sys_user`;
CREATE TABLE `sys_user` (`id` int(11) NOT NULL AUTO_INCREMENT,`username` varchar(50) NOT NULL,`password` varchar(100) DEFAULT NULL,`email` varchar(50) DEFAULT NULL,`phone` varchar(20) DEFAULT NULL,`status` int(1) DEFAULT NULL,`avatar` varchar(200) DEFAULT NULL,`deleted` int(1) DEFAULT '0',PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

二、需求二：对生成的xlsx文件调用打印机打印

2.1 Vue前端实现按钮+事件

<el-button type="warning" round icon="el-icon-printer" @click="printExcel">打印</el-button>

methods: {printExcel() {userApi.printTable().then(response => {this.$message.success('请求打印成功')})}
}

userManage.js中再写一个调用后端接口的

export default {printTable() {return request({url: `/user/print`,method: 'get',timeout: '100000'})}
}

2.2 后端实现打印

这里也干脆实现逻辑不写在Service层了，省点字，实际开发中还是要遵循规范哈

@GetMapping("/print")
public Result<?> printInfo(){try {String filepath = Constants.XLSX_DIR + "\\" + Constants.XLSX_NAME;PrintUtil.print(filepath);} catch (Exception e) {e.printStackTrace();}return Result.success();
}

核心打印工具PrintUtil.java，这个java文件稍微有点长

import com.jacob.activeX.ActiveXComponent;
import com.jacob.com.ComThread;
import com.jacob.com.Dispatch;
import com.jacob.com.Variant;
import org.apache.pdfbox.pdmodel.PDDocument;
import org.apache.pdfbox.rendering.PDFRenderer;import javax.imageio.ImageIO;
import javax.print.*;
import javax.print.attribute.DocAttributeSet;
import javax.print.attribute.HashDocAttributeSet;
import javax.print.attribute.HashPrintRequestAttributeSet;
import javax.print.attribute.standard.OrientationRequested;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.util.Arrays;
import java.util.List;public class PrintUtil {/*** 竖屏模式*/public static OrientationRequested PORTRAIT = OrientationRequested.PORTRAIT;/*** 横屏模式*/public static OrientationRequested LANDSCAPE = OrientationRequested.LANDSCAPE;/*** 获取全部打印设备信息* @return 返回全部能用的打印服务的List*/public static List<PrintService> getDeviceList() {// 构建打印请求属性集HashPrintRequestAttributeSet pras = new HashPrintRequestAttributeSet();// 设置打印格式，因为未确定类型，所以选择autosenseDocFlavor flavor = DocFlavor.BYTE_ARRAY.AUTOSENSE;// 查找所有的可用的打印服务PrintService printService[] = PrintServiceLookup.lookupPrintServices(flavor, pras);List<PrintService> list = Arrays.asList(printService);return list;}/*** 根据文件类型不同调用不同代码去打印* @param filePath 文件路径*/public static void print(String filePath) throws Exception {PrintService printService = PrintServiceLookup.lookupDefaultPrintService();String defaultDeviceName = printService.getName();print(filePath, defaultDeviceName);}/*** 额外传入一个 AfterPrint，会在打印完成后调用 afterPrint.run()* @param filePath* @param afterPrint* @throws Exception*/public static void print(String filePath, AfterPrint afterPrint) throws Exception {print(filePath);afterPrint.run();}/*** 根据文件类型不同调用不同代码去打印* @param filePath 文件路径* @param deviceName 设备名称，传入哪个设备的名称，就让哪个设备去打印*/public static void print(String filePath, String deviceName) throws Exception{List<PrintService> list = getDeviceList();PrintService printService = null;for (PrintService p : list) {if(p.getName().equals(deviceName)) {printService = p;break;}}if(printService == null) {throw new Exception("Device not found");}String type = filePath.replaceAll(".*\\.","");if("jpg".equalsIgnoreCase(type)) {normalPrint(new File(filePath), DocFlavor.INPUT_STREAM.JPEG, printService);return;}if("jpeg".equalsIgnoreCase(type)) {normalPrint(new File(filePath), DocFlavor.INPUT_STREAM.JPEG, printService);return;}if("gif".equalsIgnoreCase(type)) {normalPrint(new File(filePath), DocFlavor.INPUT_STREAM.GIF, printService);return;}if("pdf".equalsIgnoreCase(type)) {printPDF(new File(filePath), DocFlavor.INPUT_STREAM.PNG, printService);return;}if("png".equalsIgnoreCase(type)) {normalPrint(new File(filePath), DocFlavor.INPUT_STREAM.PNG, printService);return;}if("doc".equalsIgnoreCase(type)) {printWord(filePath, deviceName);return;}if("docx".equalsIgnoreCase(type)) {printWord(filePath, deviceName);return;}if("xls".equalsIgnoreCase(type)) {printExcel(filePath, deviceName);return;}if("xlsx".equalsIgnoreCase(type)) {printExcel(filePath, deviceName);return;}if("ppt".equalsIgnoreCase(type)) {printPPT(filePath, deviceName);return;}if("pptx".equalsIgnoreCase(type)) {printPPT(filePath, deviceName);return;}}/*** 会在打印完成后调用 afterPrint.run()* @param filePath* @param deviceName* @param afterPrint* @throws Exception*/public static void print(String filePath, String deviceName, AfterPrint afterPrint) throws Exception{print(filePath, deviceName);afterPrint.run();}/*** javase的打印机打印文件，支持jpg,png,gif,pdf等等* @param file 要打印的文件* @param flavor 打印格式*/private static void normalPrint(File file, DocFlavor flavor) {// 定位默认的打印服务PrintService service = PrintServiceLookup.lookupDefaultPrintService();             // 显示打印对话框normalPrint(file, flavor, service);}private static void normalPrint(File file, DocFlavor flavor, PrintService service) {normalPrint(file, flavor, PORTRAIT, service);}/*** javase的打印机打印文件，支持jpg,png,gif等等* @param file 要打印的文件* @param service 打印机选择* @param requested 设定横屏还是竖屏* @param flavor 打印格式*/private static void normalPrint(File file, DocFlavor flavor, OrientationRequested requested, PrintService service) {// 构建打印请求属性集HashPrintRequestAttributeSet pras = new HashPrintRequestAttributeSet();pras.add(requested);if (service != null) {try {DocPrintJob job = service.createPrintJob(); // 创建打印作业FileInputStream fis = new FileInputStream(file); // 构造待打印的文件流DocAttributeSet das = new HashDocAttributeSet();Doc doc = new SimpleDoc(fis, flavor, das);job.print(doc, pras);} catch (Exception e) {e.printStackTrace();}}}/*** 打印pdf的方法，因为java内置的打印pdf的方法有病，所以首先需要把pdf转换成png，然后打印png* @param file 要打印的文件* @param flavor 要打印的文件* @param service 打印设备*/private static void printPDF(File file, DocFlavor flavor, PrintService service) {try {PDDocument doc = PDDocument.load(file);PDFRenderer renderer = new PDFRenderer(doc);int pageCount = doc.getNumberOfPages();for(int i=0;i<pageCount;i++){File f = new File(file.getParent() + File.separator + "temp_" + i + ".png");BufferedImage image = renderer.renderImageWithDPI(i, 96);ImageIO.write(image, "PNG", f);normalPrint(f, flavor, LANDSCAPE, service);f.delete();}} catch (IOException e) {e.printStackTrace();} catch (Exception e) {e.printStackTrace();}}/*** 打印机打印Word* @param filepath 打印文件路径* @param deviceName 传入哪个设备名称，用哪个设备打印*/private static void printWord(String filepath, String deviceName) {if(filepath.isEmpty()){return;}ComThread.InitSTA();//使用Jacob创建 ActiveX部件对象：ActiveXComponent word=new ActiveXComponent("Word.Application");//打开Word文档Dispatch doc=null;Dispatch.put(word, "Visible", new Variant(false));word.setProperty("ActivePrinter", new Variant(deviceName));Dispatch docs=word.getProperty("Documents").toDispatch();doc=Dispatch.call(docs, "Open", filepath).toDispatch();try {Dispatch.call(doc, "PrintOut");//打印} catch (Exception e) {e.printStackTrace();}finally{try {if(doc!=null){//关闭文档Dispatch.call(doc, "Close",new Variant(0));}} catch (Exception e2) {e2.printStackTrace();}word.invoke("Quit", new Variant[] {});//关闭进程//释放资源ComThread.Release();}}/*** 打印Excel* @param filePath 打印文件路径，形如 E:\\temp\\tempfile\\1494607000581.xls* @param deviceName 传入哪个设备名称，用哪个设备打印*/private static void printExcel(String filePath, String deviceName){if(filePath.isEmpty()){return;}ComThread.InitSTA();ActiveXComponent xl=new ActiveXComponent("Excel.Application");try {Dispatch.put(xl, "Visible", new Variant(true));Dispatch workbooks = xl.getProperty("Workbooks").toDispatch();Dispatch excel=Dispatch.call(workbooks, "Open", filePath).toDispatch();Dispatch.callN(excel,"PrintOut",new Object[]{Variant.VT_MISSING, Variant.VT_MISSING, new Integer(1),new Boolean(false), deviceName, new Boolean(true),Variant.VT_MISSING, ""});Dispatch.call(excel, "Close", new Variant(false));} catch (Exception e) {e.printStackTrace();} finally{xl.invoke("Quit",new Variant[0]);ComThread.Release();}}/*** 打印PPT* @param filePath* @param deviceName*/private static void printPPT(String filePath, String deviceName) {File file = new File(filePath);File pdfFile = new File(file.getParentFile().getAbsolutePath() + file.getName() + ".pdf");ActiveXComponent app = null;Dispatch ppt = null;try {ComThread.InitSTA();app = new ActiveXComponent("PowerPoint.Application");Dispatch ppts = app.getProperty("Presentations").toDispatch();ppt = Dispatch.call(ppts, "Open", filePath, true, true, false).toDispatch();Dispatch.call(ppt, "SaveAs", pdfFile.getAbsolutePath(), 32);} catch (Exception e) {e.printStackTrace();throw e;} finally {if (ppt != null) {Dispatch.call(ppt, "Close");}if (app != null) {app.invoke("Quit");}ComThread.Release();}try {print(pdfFile.getAbsolutePath(), deviceName);pdfFile.delete();} catch (Exception e) {e.printStackTrace();}}/*** 接口，在打印结束后调用*/public interface AfterPrint {void run();}
}

PrintUtil.java中依赖两个打印需要的非常重要包，jacob和pdfbox，下面给出免费链接，阿里云盘不限速的
链接：Java打印相关依赖包

下载后，需要导入一下，也十分简单，如图

然后运行后端，点击按钮就会有对应效果了，如果你没有打印机，会弹出生成PDF，有打印机连着，会使用默认打印机，或者通过PrintUtil中方法自定义打印机名称，选择打印机打印

以上就是全部内容，过程有啥问题可以评论区和大家一起交流！