知识准备
需要理解Apache POI遵循的标准（Office Open XML（OOXML）标准和微软的OLE 2复合文档格式（OLE2））， 这将对应着API的依赖包。
什么是POI
apache poi 是用java编写的免费开源的跨平台的 java api，apache poi提供api给java程序对microsoft office格式档案读和写的功能。poi为“poor obfuscation implementation”的首字母缩写，意为“简洁版的模糊实现”。
Apache POI 是创建和维护操作各种符合Office Open XML（OOXML）标准和微软的OLE 2复合文档格式（OLE2）的Java API。更多请参考 官方文档。
实现案例
这里展示SpringBoot集成POI导出用户信息的Word例子。
Pom依赖
引入poi的依赖包
立即学习“Java免费学习笔记（深入）”；
org.apache.poi poi 5.2.2 org.apache.poi poi-ooxml 5.2.2
导出Word
UserController中导出的方法
package tech.pdai.springboot.file.word.poi.controller;
import java.io.OutputStream;
import javax.servlet.http.HttpServletResponse;
import io.swagger.annotations.ApiOperation;
import org.apache.poi.xwpf.usermodel.XWPFDocument;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import tech.pdai.springboot.file.word.poi.service.IUserService;
/**
* @author pdai
*/
@RestController
@RequestMapping("/user")
public class UserController {
@Autowired
private IUserService userService;
@ApiOperation("Download Word")
@GetMapping("/word/download")
public void download(HttpServletResponse response){
try {
XWPFDocument document = userService.generateWordXWPFDocument();
response.reset();
response.setContentType("application/vnd.ms-excel");
response.setHeader("Content-disposition",
"attachment;filename=user_world_" + System.currentTimeMillis() + ".docx");
OutputStream os = response.getOutputStream();
document.write(os);
os.close();
} catch (Exception e) {
e.printStackTrace();
}
}
}UserServiceImple中导出Word方法
package tech.pdai.springboot.file.word.poi.service.impl;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.math.BigInteger;
import java.util.ArrayList;
import java.util.List;
import lombok.extern.slf4j.Slf4j;
import org.apache.poi.openxml4j.exceptions.InvalidFormatException;
import org.apache.poi.util.Units;
import org.apache.poi.xwpf.usermodel.BreakType;
import org.apache.poi.xwpf.usermodel.Document;
import org.apache.poi.xwpf.usermodel.ParagraphAlignment;
import org.apache.poi.xwpf.usermodel.XWPFDocument;
import org.apache.poi.xwpf.usermodel.XWPFParagraph;
import org.apache.poi.xwpf.usermodel.XWPFRun;
import org.apache.poi.xwpf.usermodel.XWPFTable;
import org.apache.poi.xwpf.usermodel.XWPFTableCell;
import org.openxmlformats.schemas.wordprocessingml.x2006.main.CTTblPr;
import org.openxmlformats.schemas.wordprocessingml.x2006.main.CTTblWidth;
import org.springframework.core.io.ClassPathResource;
import org.springframework.core.io.Resource;
import org.springframework.stereotype.Service;
import tech.pdai.springboot.file.word.poi.entity.User;
import tech.pdai.springboot.file.word.poi.service.IUserService;
/**
* @author pdai
*/
@Slf4j
@Service
public class UserServiceImpl implements IUserService {
@Override
public XWPFDocument generateWordXWPFDocument(){
XWPFDocument doc = new XWPFDocument();
// Title
createTitle(doc, "Java 全栈知识体系");
// Chapter 1
createChapterH1(doc, "1. 知识准备");
createChapterH2(doc, "1.1 什么是POI");
createParagraph(doc, "Apache POI 是创建和维护操作各种符合Office Open XML（OOXML）标准和微软的OLE 2复合文档格式（OLE2）的Java API。用它可以使用Java读取和创建,修改MS Excel文件.而且,还可以使用Java读取和创建MS Word和MSPowerPoint文件。更多请参考[官方文档](https://poi.apache.org/index.html)");
createChapterH2(doc, "1.2 POI中基础概念");
createParagraph(doc, "生成xls和xlsx有什么区别？POI对Excel中的对象的封装对应关系？");
// Chapter 2
createChapterH1(doc, "2. 实现案例");
createChapterH2(doc, "2.1 用户列表示例");
createParagraph(doc, "以导出用户列表为例");
// 表格
List userList = getUserList();
XWPFParagraph paragraph = doc.createParagraph();
XWPFTable table = paragraph.getDocument().createTable(userList.size(), 5);
table.setWidth(500);
table.setCellMargins(20, 20, 20, 20);
//表格属性
CTTblPr tablePr = table.getCTTbl().addNewTblPr();
//表格宽度
CTTblWidth width = tablePr.addNewTblW();
width.setW(BigInteger.valueOf(8000));
for(int i = 0; i< userList.size(); i++) {
List tableCells = table.getRow(i).getTableCells();
tableCells.get(0).setText(userList.get(i).getId()+"");
tableCells.get(1).setText(userList.get(i).getUserName());
tableCells.get(2).setText(userList.get(i).getEmail());
tableCells.get(3).setText(userList.get(i).getPhoneNumber()+"");
tableCells.get(4).setText(userList.get(i).getDescription());
}
createChapterH2(doc, "2.2 图片导出示例");
createParagraph(doc, "以导出图片为例");
// 图片
InputStream stream = null;
try {
XWPFParagraph paragraph3 = doc.createParagraph();
Resource resource = new ClassPathResource("pdai-guli.png");
stream = new FileInputStream(resource.getFile());
XWPFRun run = paragraph3.createRun();
run.addPicture(stream, Document.PICTURE_TYPE_PNG, "Generated", Units.toEMU(256), Units.toEMU(256));
} catch (IOException | InvalidFormatException e) {
e.printStackTrace();
}
return doc;
}
private void createTitle(XWPFDocument doc, String content){
XWPFParagraph title = doc.createParagraph();
title.setAlignment(ParagraphAlignment.CENTER);
XWPFRun r1 = title.createRun();
r1.setBold(true);
r1.setFontFamily("宋体");
r1.setText(content);
r1.setFontSize(22);
}
private void createChapterH1(XWPFDocument doc, String content){
XWPFParagraph actTheme = doc.createParagraph();
actTheme.setAlignment(ParagraphAlignment.LEFT);
XWPFRun runText1 = actTheme.createRun();
runText1.setBold(true);
runText1.setText(content);
runText1.setFontSize(18);
}
private void createChapterH2(XWPFDocument doc, String content){
XWPFParagraph actType = doc.createParagraph();
XWPFRun runText2 = actType.createRun();
runText2.setBold(true);
runText2.setText(content);
runText2.setFontSize(15);
}
private void createParagraph(XWPFDocument doc, String content){
XWPFParagraph actType = doc.createParagraph();
XWPFRun runText2 = actType.createRun();
runText2.setText(content);
runText2.setFontSize(11);
}
private List getUserList(){
List userList = new ArrayList<>();
for (int i = 0; i < 5; i++) {
userList.add(User.builder()
.id(Long.parseLong(i + "")).userName("pdai" + i).email("pdai@pdai.tech" + i).phoneNumber(121231231231L)
.description("hello world" + i)
.build());
}
return userList;
}
} 导出：
导出后的word：
