一、概要
在实际业务中,我们经常需要从Excel文件中提取数据,其中包括单元格数据和图片信息。本文将详细介绍三种读取Excel图片的技术方案,分别针对悬浮式图片、WPS嵌入式图片和Office嵌入式图片。
二、核心类说明
类名 | 功能描述 |
---|---|
ExcelController | 提供三个上传接口,分别对应三种图片读取方式 |
ExcelService | 抽象基类,包含通用解析逻辑和图片保存方法 |
ExcelServiceFloatImpl | 处理悬浮式图片的实现类 |
ExcelServiceImplantWpsImpl | 处理WPS嵌入式图片的实现类 |
ExcelServiceImplantOfficeImpl | 处理Office嵌入式图片的实现类 |
ExcelVO | 数据载体类,存储行号和单元格数据 |
ImagePosition | 图片位置信息类 |
ImageInfo | 图片信息辅助类 |
三、控制器接口
java
@RestController
@RequestMapping("/excel")
public class ExcelController {
@Resource
private ExcelService excelServiceFloatImpl;
@Resource
private ExcelService excelServiceImplantWpsImpl;
@Resource
private ExcelService excelServiceImplantOfficeImpl;
// 悬浮式图片读取接口
@PostMapping("/upload/float")
public ResponseEntity<List<ExcelVO>> uploadExcelFloat(@RequestParam("file") MultipartFile file)
// WPS嵌入式图片读取接口
@PostMapping("/upload/implant/wps")
public ResponseEntity<List<ExcelVO>> uploadExcelImplantWps(@RequestParam("file") MultipartFile file)
// Office嵌入式图片读取接口
@PostMapping("/upload/implant/office")
public ResponseEntity<List<ExcelVO>> uploadExcelImplantOffice(@RequestParam("file") MultipartFile file)
}
四、抽象父类
java
import com.central.common.exception.BusinessException;
import lombok.extern.slf4j.Slf4j;
import org.apache.poi.openxml4j.opc.OPCPackage;
import org.apache.poi.openxml4j.opc.PackageAccess;
import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.DataFormatter;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.xssf.usermodel.XSSFSheet;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;
import org.springframework.web.multipart.MultipartFile;
import java.io.File;
import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.*;
@Slf4j
public abstract class ExcelService {
// 定义从第几行开始读取(从0开始计算,6则为第七行)
public static final int START_ROW_INDEX = 6;
/**
* 解析上传的Excel文件
*
* @param file 上传的Excel文件
* @return 解析后的数据列表
*/
public List<ExcelVO> parseExcel(MultipartFile file) throws Exception {
if (file == null || file.isEmpty()) {
return Collections.emptyList();
}
// 校验文件扩展名
String filename = file.getOriginalFilename();
if (filename == null || !filename.toLowerCase().endsWith(".xlsx")) {
throw new BusinessException("仅支持.xlsx格式文件");
}
if (file.getSize() > 55 * 1024 * 1024) {
throw new BusinessException("文件大小不能超过55MB");
}
File tempFile = null;
try {
// 创建临时文件
List<ExcelVO> result = new ArrayList<>();
tempFile = File.createTempFile("excel_temp_", ".xlsx");
file.transferTo(tempFile);
try (OPCPackage pkg = OPCPackage.open(tempFile, PackageAccess.READ);
XSSFWorkbook workbook = new XSSFWorkbook(pkg)) {
XSSFSheet sheet = workbook.getSheetAt(0);
// 读取单元格数据
for (int i = START_ROW_INDEX; i <= sheet.getLastRowNum(); i++) {
Row row = sheet.getRow(i);
if (row == null) {
continue;
}
ExcelVO vo = new ExcelVO();
vo.setRowNum(i + 1);
List<String> cellValues = new ArrayList<>();
DataFormatter dataFormatter = new DataFormatter(Locale.CHINA);
for (Cell cell : row) {
cellValues.add(dataFormatter.formatCellValue(cell));
}
vo.setCellValues(cellValues);
result.add(vo);
}
return readExcel(result, pkg, sheet);
}
} catch (Exception e) {
log.error("解析失败", e);
} finally {
// 删除临时文件
if (tempFile != null && tempFile.exists()) {
boolean deleted = tempFile.delete();
if (!deleted) {
log.warn("临时文件删除失败: {}", tempFile.getAbsolutePath());
}
}
}
return null;
}
/**
* 保存图片到本地
*
* @param imageData 图片字节数组
* @param rowNum 图片所在行号
* @param colNum 图片所在列号
*/
String saveImageToLocal(byte[] imageData, int rowNum, int colNum, String extension) {
try {
Path saveDir = Paths.get("D:\\image");
if (!Files.exists(saveDir)) {
Files.createDirectories(saveDir);
}
String fileName = String.format("row_%d_col_%d_%s.%s",
rowNum, colNum, UUID.randomUUID(), extension);
Path filePath = saveDir.resolve(fileName);
Files.write(filePath, imageData);
return filePath.toString();
} catch (IOException e) {
log.error("保存图片到本地失败", e);
return null;
}
}
public abstract List<ExcelVO> readExcel(List<ExcelVO> result, OPCPackage pkg, XSSFSheet sheet) throws Exception;
}
五、悬浮式图片读取
java
import lombok.extern.slf4j.Slf4j;
import org.apache.poi.openxml4j.opc.OPCPackage;
import org.apache.poi.xssf.usermodel.*;
import org.springframework.stereotype.Service;
import java.util.*;
@Service
@Slf4j
public class ExcelServiceFloatImpl extends ExcelService {
@Override
public List<ExcelVO> readExcel(List<ExcelVO> result, OPCPackage pkg, XSSFSheet sheet) throws Exception {
if (sheet.getDrawingPatriarch() == null) {
return result;
}
// 读取图片
for (XSSFShape shape : sheet.getDrawingPatriarch().getShapes()) {
if (shape instanceof XSSFPicture) {
XSSFPicture picture = (XSSFPicture) shape;
if (picture.getAnchor() instanceof XSSFClientAnchor) {
XSSFClientAnchor anchor = (XSSFClientAnchor) picture.getAnchor();
int pictureRow = anchor.getRow1();
if (pictureRow >= START_ROW_INDEX) {
int resultIndex = pictureRow - START_ROW_INDEX;
if (resultIndex < result.size()) {
byte[] data = picture.getPictureData().getData();
String filePath = saveImageToLocal(
data,
pictureRow + 1,
anchor.getCol1() + 1,
picture.getPictureData().suggestFileExtension()
);
ExcelVO vo = result.get(resultIndex);
ImagePosition imagePosition = new ImagePosition();
imagePosition.setCol(anchor.getCol1() + 1);
imagePosition.setRow(pictureRow + 1);
imagePosition.setUrl(filePath);
vo.setImagePositions(imagePosition);
}
}
}
}
}
return result;
}
// 获取悬浮图片
private Map<Integer, ImagePosition> getFloatingPictures(XSSFSheet sheet) throws Exception {
Map<Integer, ImagePosition> pictures = new HashMap<>();
XSSFDrawing drawing = sheet.getDrawingPatriarch();
if (drawing != null) {
for (XSSFShape shape : drawing.getShapes()) {
if (shape instanceof XSSFPicture) {
XSSFPicture picture = (XSSFPicture) shape;
if (picture.getAnchor() instanceof XSSFClientAnchor) {
XSSFClientAnchor anchor = (XSSFClientAnchor) picture.getAnchor();
int pictureRow = anchor.getRow1();
if (pictureRow >= START_ROW_INDEX) {
byte[] data = picture.getPictureData().getData();
String filePath = saveImageToLocal(
data,
pictureRow + 1,
anchor.getCol1() + 1,
picture.getPictureData().suggestFileExtension()
);
ImagePosition imagePosition = new ImagePosition();
imagePosition.setCol(anchor.getCol1() + 1);
imagePosition.setRow(pictureRow + 1);
imagePosition.setUrl(filePath);
pictures.put(anchor.getRow1() + 1, imagePosition);
}
}
}
}
}
return pictures;
}
}
六、Office Excel嵌入式图片读取
通过观察发现Office嵌入图片后,在内部 一个XML文件(xl\worksheets\sheet1.xml)中,嵌入图片对应的单元格标签(C 标签)会包含一个 "vm" 属性,该属性的取值恰好与图片名称(图片存放在xl\media中)中的递增数值一致。基于这一对应关系,通过查找单元格 C标签的 "vm" 属性值,即可匹配到对应的图片文件,从而完成嵌入式图片的读取。
Excel
xl\media
xl\worksheets\sheet1.xml
实现逻辑:
- 解析工作表XML(sheet1.xml),获取AB列单元格的vm属性(该属性与图片索引关联)和行号。
- 遍历Excel包中的媒体文件(位于/xl/media/),建立图片索引和图片数据的映射。
- 根据vm值匹配图片,将图片保存到本地,并设置到对应的行
存在问题
只用Office Excel编辑时,VM与图片属性对应不会存在问题。但用WPS与Office Excel混合嵌入不同格式的图片时可能会导致VM属性与Image图片数值对应不上,请注意!!!
java
import lombok.extern.slf4j.Slf4j;
import org.apache.poi.openxml4j.opc.OPCPackage;
import org.apache.poi.openxml4j.opc.PackagePart;
import org.apache.poi.openxml4j.opc.PackagingURIHelper;
import org.apache.poi.xssf.usermodel.XSSFSheet;
import org.springframework.stereotype.Service;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import java.io.*;
import java.util.*;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
@Service
@Slf4j
public class ExcelServiceImplantOfficeImpl extends ExcelService {
private static final Pattern CELL_REF_PATTERN = Pattern.compile("AB(\\d+)");
private static final Pattern IMAGE_PATH_PATTERN = Pattern.compile("/xl/media/image(\\d+)\\.(\\w+)");
@Override
public List<ExcelVO> readExcel(List<ExcelVO> result, OPCPackage pkg, XSSFSheet sheet) throws Exception {
// 获取工作表XML内容
PackagePart sheetPart = pkg.getPart(PackagingURIHelper.createPartName("/xl/worksheets/sheet1.xml"));
InputStream sheetStream = sheetPart.getInputStream();
// 解析工作表XML获取AB列单元格的vm属性
Map<Integer, Integer> vmMap = parseSheetXML(sheetStream);
sheetStream.close();
// 获取所有图片并建立索引映射
Map<Integer, ImageInfo> imageMap = getAllImages(pkg);
//根据vm值匹配图片并保存
for (Map.Entry<Integer, Integer> entry : vmMap.entrySet()) {
int vm = entry.getKey();
if (imageMap.containsKey(vm)) {
//office 读到的是实际行号,list集合从0开始计算所以要减1
int resultIndex = entry.getValue() - START_ROW_INDEX - 1;
if (resultIndex < result.size()) {
ImageInfo imageInfo = imageMap.get(vm);
ImagePosition imagePosition = new ImagePosition();
imagePosition.setCol(entry.getValue());
imagePosition.setUrl(saveImageToLocal(
imageInfo.getFileBytes(),
entry.getValue(),
28,
imageInfo.getExtension()
));
ExcelVO vo = result.get(resultIndex);
vo.setImagePositions(imagePosition);
}
}
}
return result;
}
// 解析工作表XML获取AB列单元格的vm属性 k:vm value:行号
private Map<Integer, Integer> parseSheetXML(InputStream is) throws Exception {
Map<Integer, Integer> vmMap = new HashMap<>();
DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
DocumentBuilder builder = factory.newDocumentBuilder();
Document doc = builder.parse(is);
NodeList cells = doc.getElementsByTagName("c");
for (int i = 0; i < cells.getLength(); i++) {
Node cellNode = cells.item(i);
if (cellNode.getNodeType() == Node.ELEMENT_NODE) {
Element cellElement = (Element) cellNode;
String cellRef = cellElement.getAttribute("r");
// 只需要AB列且行号>=7
Matcher matcher = CELL_REF_PATTERN.matcher(cellRef);
if (matcher.matches()) {
int rowNum = Integer.parseInt(matcher.group(1));
if (rowNum >= 7) {
String vmAttr = cellElement.getAttribute("vm");
if (!vmAttr.isEmpty()) {
int vm = Integer.parseInt(vmAttr);
vmMap.put(vm, rowNum);
}
}
}
}
}
return vmMap;
}
// 获取所有图片并建立索引映射 k:图片索引 value :图片信息
private Map<Integer, ImageInfo> getAllImages(OPCPackage pkg) throws Exception {
Map<Integer, ImageInfo> imageMap = new HashMap<>();
// 遍历所有文件
for (PackagePart part : pkg.getParts()) {
String partName = part.getPartName().toString();
if (partName.startsWith("/xl/media/")) {
Matcher matcher = IMAGE_PATH_PATTERN.matcher(partName);
if (matcher.matches() && "png".equalsIgnoreCase(matcher.group(2))) {
try (InputStream is = part.getInputStream();
ByteArrayOutputStream bos = new ByteArrayOutputStream()) {
byte[] buffer = new byte[4096];
int bytesRead;
while ((bytesRead = is.read(buffer)) != -1) {
bos.write(buffer, 0, bytesRead);
}
ImageInfo imagePosition = new ImageInfo();
imagePosition.setExtension(matcher.group(2).toLowerCase());
imagePosition.setFileBytes(bos.toByteArray());
imageMap.put(Integer.parseInt(matcher.group(1)), imagePosition);
}
}
}
}
return imageMap;
}
}
七、WPS嵌入式图片读取
具体实现逻辑可参考其他人博客,以下代码参考该文章修改实现
实现类:
java
import com.alibaba.cloud.commons.lang.StringUtils;
import lombok.extern.slf4j.Slf4j;
import org.apache.commons.compress.utils.IOUtils;
import org.apache.poi.openxml4j.opc.OPCPackage;
import org.apache.poi.openxml4j.opc.PackagePart;
import org.apache.poi.openxml4j.opc.PackagePartName;
import org.apache.poi.xssf.usermodel.XSSFSheet;
import org.jdom2.Attribute;
import org.jdom2.Document;
import org.jdom2.Element;
import org.jdom2.input.SAXBuilder;
import org.springframework.stereotype.Service;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;
import java.io.File;
import java.util.*;
/**
* @author mashb
*/
@Service
@Slf4j
public class ExcelServiceImplantWpsImpl extends ExcelService {
@Override
public List<ExcelVO> readExcel(List<ExcelVO> result, OPCPackage pkg, XSSFSheet sheet) throws Exception {
//获取所有包文件
List<PackagePart> parts = pkg.getParts();
//获取每个工作表中的包文件
Map<Integer, List<PackagePart>> picturePath = getEmbedPictures(parts);
for (Integer key : picturePath.keySet()) {
List<PackagePart> rows = picturePath.get(key);
if (rows.size() < START_ROW_INDEX) {
return result;
}
for (int i = START_ROW_INDEX; i < rows.size(); i++) {
int resultIndex = i - START_ROW_INDEX;
if (resultIndex < result.size()) {
PackagePart part = rows.get(i);
// 获取文件名
String partName = part.getPartName().getName();
String fileName = new File(partName).getName();
String extension = fileName.substring(fileName.lastIndexOf('.') + 1);
ExcelVO vo = result.get(resultIndex);
ImagePosition imagePosition = new ImagePosition();
imagePosition.setCol(28);
imagePosition.setRow(i + 1);
imagePosition.setUrl(saveImageToLocal(
IOUtils.toByteArray(part.getInputStream()),
i + 1,
28,
extension.toLowerCase()
));
vo.setImagePositions(imagePosition);
}
}
}
return result;
}
private static Map<Integer, List<PackagePart>> getEmbedPictures(List<PackagePart> parts) throws Exception {
Map<String, Set<String>> mapImg = new HashMap<>();
Map<String, String> mapImgPath = new HashMap<>();
Map<Integer, List<String>> dataMap = new HashMap<>();
for (PackagePart part : parts) {
PackagePartName partName = part.getPartName();
String name = partName.getName();
if ("/xl/cellimages.xml".equals(name)) {
SAXBuilder builder = new SAXBuilder();
// 获取文档
Document doc = builder.build(part.getInputStream());
// 获取根节点
Element root = doc.getRootElement();
List<Element> cellImageList = root.getChildren();
for (Element imgEle : cellImageList) {
Element xdrPic = imgEle.getChildren().get(0);
Element xdrNvPicPr = xdrPic.getChildren().get(0);
Element xdrBlipFill = xdrPic.getChildren().get(1);
Element aBlip = xdrBlipFill.getChildren().get(0);
Attribute attr = aBlip.getAttributes().get(0);
String imgId = xdrNvPicPr.getChildren().get(0).getAttributeValue("name");
String id = attr.getValue();
if (mapImg.containsKey(id)) {
mapImg.get(id).add(imgId);
} else {
Set<String> set = new HashSet<>();
set.add(imgId);
mapImg.put(id, set);
}
}
}
if ("/xl/_rels/cellimages.xml.rels".equals(name)) {
SAXBuilder builder = new SAXBuilder();
// 获取文档
Document doc = builder.build(part.getInputStream());
// 获取根节点
Element root = doc.getRootElement();
List<Element> relationshipList = root.getChildren();
for (Element relationship : relationshipList) {
String id = relationship.getAttributeValue("Id");
String target = relationship.getAttributeValue("Target");
mapImgPath.put(id, target);
}
}
if (name.contains("/xl/worksheets/sheet")) {
// 获取文档
String sheetNoStr = name.replace("/xl/worksheets/sheet", "").replace(".xml", "");
Integer sheetNo = Integer.valueOf(sheetNoStr) - 1;
// 步骤1:创建SAXParserFactory实例
SAXParserFactory factory = SAXParserFactory.newInstance();
// 步骤2:创建SAXParser实例
SAXParser parser = factory.newSAXParser();
MySAXParserHandler handler = new MySAXParserHandler();
parser.parse(part.getInputStream(), handler);
List<String> rows = handler.getRows();
dataMap.put(sheetNo, rows);
}
}
Map<String, String> imgMap = new HashMap<>();
for (String id : mapImg.keySet()) {
Set<String> imgIds = mapImg.get(id);
String path = mapImgPath.get(id);
for (String imgId : imgIds) {
imgMap.put(imgId, path);
}
}
for (Integer key : dataMap.keySet()) {
List<String> rows = dataMap.get(key);
for (int i = 0; i < rows.size(); i++) {
String imgId = rows.get(i);
if (imgMap.containsKey(imgId)) {
rows.set(i, imgMap.get(imgId));
}
}
}
Map<Integer, List<PackagePart>> map = new HashMap<>();
for (Integer key : dataMap.keySet()) {
List<PackagePart> list = new ArrayList<>();
map.put(key, list);
List<String> pathList = dataMap.get(key);
for (int i = 0; i < pathList.size(); i++) {
list.add(i, null);
String path = pathList.get(i);
if (StringUtils.isNotEmpty(path)) {
for (PackagePart part : parts) {
PackagePartName partName = part.getPartName();
String name = partName.getName();
if (name.contains(path)) {
list.set(i, part);
break;
}
}
}
}
}
return map;
}
}
SAX解析类
java
import lombok.Data;
import lombok.EqualsAndHashCode;
import org.xml.sax.Attributes;
import org.xml.sax.SAXException;
import org.xml.sax.helpers.DefaultHandler;
import java.util.ArrayList;
import java.util.List;
@Data
@EqualsAndHashCode(callSuper = true)
public class MySAXParserHandler extends DefaultHandler {
String value = null;
List<String> rows = new ArrayList<>();
int rowIndex = 0;
/**
* 用来标识解析开始
*/
@Override
public void startDocument() throws SAXException {
super.startDocument();
}
/**
* 用来标识解析结束
*/
@Override
public void endDocument() throws SAXException {
super.endDocument();
}
/**
* 解析xml元素
*/
@Override
public void startElement(String uri, String localName, String qName, Attributes attributes) throws SAXException {
// 调用DefaultHandler类的startElement方法
super.startElement(uri, localName, qName, attributes);
if (("row").equals(qName)) {
value = "";
}
}
@Override
public void endElement(String uri, String localName, String qName)
throws SAXException {
//调用DefaultHandler类的endElement方法
super.endElement(uri, localName, qName);
if (("row").equals(qName)) {
if (value != null && value.contains("DISPIMG")) {
value = value.substring(value.lastIndexOf("DISPIMG(")).replace("DISPIMG(\"", "");
value = value.substring(0, value.indexOf("\""));
rows.add(rowIndex, value);
} else {
rows.add(rowIndex, null);
}
rowIndex++;
value = "";
}
}
@Override
public void characters(char[] ch, int start, int length)
throws SAXException {
super.characters(ch, start, length);
value += new String(ch, start, length);
}
}
八、辅助类
ExcelVO
java
import lombok.Data;
import java.util.List;
@Data
public class ExcelVO {
// 行号
private int rowNum;
// 单元格值列表
private List<String> cellValues;
// 图片位置信息(可选)
private ImagePosition imagePositions;
}
ImageInfo
java
import lombok.Data;
@Data
public class ImageInfo {
private String extension;
private byte[] fileBytes;
}
ImagePosition
java
import lombok.Data;
@Data
public class ImagePosition {
private int row;
private int col;
private String url;
}