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二.ByteBuddy字节码增强动态创建类
1.依赖
dependencies因为Excel列是通过类对象字段注解来添加在不确定Excel列数的情况下就需要动态生成列对应类对象字段也需要动态生成
二.ByteBuddy字节码增强动态创建类
1.依赖
dependenciesdependencygroupIdnet.bytebuddy/groupIdartifactIdbyte-buddy/artifactIdversion1.11.17/version/dependency
/dependencies
2.动态创建类
public Class? extends ExcelRecordDynamicDTO getDynamicClass(ChatBatchRequestVO chatBatchRequest) throws NoSuchFieldException, IllegalAccessException, InstantiationException {DynamicType.BuilderExcelRecordDynamicDTO dynamicClass new ByteBuddy().subclass(ExcelRecordDynamicDTO.class);dynamicClass dynamicClass.defineField(question, String.class, Visibility.PUBLIC).annotateField(AnnotationDescription.Builder.ofType(ExcelColumn.class).define(value, new String(问题)).define(col, 1).build()).defineMethod(getQuestion, String.class, Visibility.PUBLIC).intercept(FieldAccessor.ofBeanProperty()).defineMethod(setQuestion, void.class, Visibility.PUBLIC).withParameters(String.class).intercept(FieldAccessor.ofBeanProperty());for (int i 0; i chatBatchRequest.getModelTypeId().length; i) {dynamicClass dynamicClass.defineField(answer i, String.class, Visibility.PUBLIC).annotateField(AnnotationDescription.Builder.ofType(ExcelColumn.class).define(value, new String(ChatModelTypeEnum.getmodelShowNameByType(chatBatchRequest.getModelTypeId()[i]))).define(col, i 2).build()).defineMethod(getAnswer i, String.class, Visibility.PUBLIC).intercept(FieldAccessor.ofBeanProperty()).defineMethod(setAnswer i, void.class, Visibility.PUBLIC).withParameters(String.class).intercept(FieldAccessor.ofBeanProperty());}Class? extends ExcelRecordDynamicDTO d dynamicClass.make().load(ExcelRecordDynamicDTO.class.getClassLoader()).getLoaded();return d;}
动态类如下所示
public class ExcelRecordDynamicDTO implements Serializable {//动态生成的字段和注解如下所示//ExcelColum(value第一列, col1)//private String col1;
} 3.实例化赋值
//实例化
Class? extends ExcelRecordDynamicDTO dy getDynamicClass(chatBatchRequest);
ExcelRecordDynamicDTO dtp dy.newInstatnce();//赋值
Field[] cityCode dto.getClass().getDeclaredFields();
for (Filed f : cityCode) {f.setAccessible(true)f.set(dto, 赋值);
}//获取值
dto.getClass().getDeclaredField(question).get(dto) 4.创建Excel
ListExcelRecordDynamicDTO resultList new ArrayList();
resultList.add(dto);ExcelUtil.writeExcel(resultList,dy.newInstance());
三.Excel工具类 1.依赖
dependenciesdependencygroupIdorg.apache.poi/groupIdartifactIdpoi/artifactIdversion3.13/version/dependencydependencygroupIdorg.apache.poi/groupIdartifactIdpoi-ooxml/artifactIdversion3.13/version/dependency
/dependencies
2.Excel代码
注解如下
Target({ElementType.FIELD})
Retention(RetentionPolicy.RUNTIME)
Documented
public interface ExcelColumn {//标题String value() default ;//Excel从左往右排列位置int col() default 0;
}
Excel工具类使用apache.poi
public class ExcelUtil {private final static String EXCEL2003 xls;private final static EXCEL2007 xlsx;public static T ListT readExcel(String path, ClassT cls, File file) {String fileName file.getName();if (!fileName.matches(^.\\.)?i)(xls)$) !fineName.matches(^.\\.(?i)(xlsx)$)) {log.error(格式错误);}ListT dataList new ArrayList();Workbook workbook null;try {if (fileName.endsWith(EXCEL2007)) {InputStream is new FileInputStream(new File(path));workbook new XSSFWorkbook(is);}if (fileName.endsWith(EXCEL2003)) {InputStream is new FileInputStream(new File(path));workbook new HSSFWorkbook(is);} if (workbook ! null ) {MapString, ListField classMap new HashMap();ListField fields Stream.of(cls.getDeclaredFields()).collectors.toList());fields.forEach(field - {ExcelColumn annotaion field.getAnnotation(ExcelColum.class);if (annotaion ! null) {String value annotation.value();if (StringUtils.isBlank(value)) {return;}if (!classMap.containsKey(value)) {classMap.put(value, new ArrayList());}field.setAccessible(true);classMap.get(value).add(field);}});//索引---columnsMapInteger, ListField refectionMap new HashMap(16);//默认读取第一个sheetSheet sheet workbook.getSheetAt(0);booleasn firstRow true;for (int i sheet.getFirstRowNum(); i sheet.getLastRowNum(); i) {Row row sheet.getRow(i);//首行 提取注解if (firstRow) {for (int j row.getFirstCellNum(); j row.getLastCellNum(); j) {Cell cell row.getCell(j);String cellValue getCellValue(cell);if (classMap.containsKey(cellValue) {reflectionMap.put(j, classMap.get(cellValue));}}firstRow false;} else {//忽略空白行if (row null) {continue;}try {T t cls.newInstance();//判断是否为空白行boolean allBlank true;for (int j row.getFirstCellNum(); j row.getLastCellNum(); j) {if (reflectionMap.containsKey(j)) {Cell cell row.getCell(j);String cellValue getCellValue(cell);if (StringUtils.isNotBlank(cellValue)) {allBlank false;}ListField fieldList reflectionMap.get(j);fieldList.foeEach(x - {try {handleField(t, cellValue, x);} catch (Exception e) {log.error(e);}});}}if (!allBlank) {dataList.add(t);} else {log.warn(ignore!);} } catch (Exception e) {log.error(e);}}}}} catch (Exception e) {log.error(e);} finally {if (workbook ! null {try {workbook.close();} catch (Exception e) {log.error(e);}}}return dataList;}public static T ListT readExcel(ClassT cls, MultipartFile file) {String fileName file.getOriginalFilename();if (!fileName.matches(^.\\.)?i)(xls)$) !fineName.matches(^.\\.(?i)(xlsx)$)) {log.error(格式错误);}ListT dataList new ArrayList();Workbook workbook null;try {InputStream is file.getInputStream();if (fileName.endsWith(EXCEL2007)) {workbook new XSSFWorkbook(is);}if (fileName.endsWith(EXCEL2003)) {workbook new HSSFWorkbook(is);} if (workbook ! null ) {MapString, ListField classMap new HashMap();ListField fields Stream.of(cls.getDeclaredFields()).collectors.toList());fields.forEach(field - {ExcelColumn annotaion field.getAnnotation(ExcelColum.class);if (annotaion ! null) {String value annotation.value();if (StringUtils.isBlank(value)) {return;}if (!classMap.containsKey(value)) {classMap.put(value, new ArrayList());}field.setAccessible(true);classMap.get(value).add(field);}});//索引---columnsMapInteger, ListField refectionMap new HashMap(16);//默认读取第一个sheetSheet sheet workbook.getSheetAt(0);booleasn firstRow true;for (int i sheet.getFirstRowNum(); i sheet.getLastRowNum(); i) {Row row sheet.getRow(i);//首行 提取注解if (firstRow) {for (int j row.getFirstCellNum(); j row.getLastCellNum(); j) {Cell cell row.getCell(j);String cellValue getCellValue(cell);if (classMap.containsKey(cellValue) {reflectionMap.put(j, classMap.get(cellValue));}}firstRow false;} else {//忽略空白行if (row null) {continue;}try {T t cls.newInstance();//判断是否为空白行boolean allBlank true;for (int j row.getFirstCellNum(); j row.getLastCellNum(); j) {if (reflectionMap.containsKey(j)) {Cell cell row.getCell(j);String cellValue getCellValue(cell);if (StringUtils.isNotBlank(cellValue)) {allBlank false;}ListField fieldList reflectionMap.get(j);fieldList.foeEach(x - {try {handleField(t, cellValue, x);} catch (Exception e) {log.error(e);}});}}if (!allBlank) {dataList.add(t);} else {log.warn(ignore!);} } catch (Exception e) {log.error(e);}}}}} catch (Exception e) {log.error(e);} finally {if (workbook ! null {try {workbook.close();} catch (Exception e) {log.error(e);}}}return dataList;}private static T void handleField(T t, String value, Field field) trows Exception {Class? type field.getType();if (type null || type void.class || StringUtils.isBlank(value)) {return;}if (type Object.class) {field.set(t, value);} else if (type.getSuperclass() null || type.getSuperclass() Number.calss) {if (type int.class || type Integer.class) {field.set(t, NumberUtils.toInt(value));} else if (type long.class || type Long.calss ) {field.set(t, NumberUtils.toLong(value));} else if (type byte.class || type Byte.calss ) {field.set(t, NumberUtils.toByte(value));} else if (type short.class || type Short.calss ) {field.set(t, NumberUtils.toShort(value));} else if (type double.class || type Double.calss ) {field.set(t, NumberUtils.toDouble(value));} else if (type float.class || type Float.calss ) {field.set(t, NumberUtils.toFloat(value));} else if (type char.class || type Character.calss ) {field.set(t, NumberUtils.toChar(value));} else if (type boolean.class) {field.set(t, NumberUtils.toBoolean(value));} else if (type BigDecimal.class) {field.set(t, new BigDecimal(value));}} else if (type Boolean.class) {field.set(t, BooleanUtils.toBoolean(value));} else if (type Data.class) {SimpleDateFprmat format new SimpleDateFormat(EEE MMM dd HH:mm:ss zzz yyyy, Locale.US);field.set(t, format.parse(value));} else if (type String.class) {field.set(t, value);} else {Constructor? constructor type.getConstructor(String.class);field.set(t, constructor .newInstance(value));}}private static String getCellValue(Cell cell) {if (cell null) {return ;}if (cell.getCellType() Cell CELL_TYPE_NUMERIC) {if (HSSFDateUtil.isCellDateFormatted(cell)) {return HSSDateUtil.getJavaDate(cell.getNumericCellValue()).toString();}else {return new BigDecimal(cell.getNumericCellValue()).toString();}} else if (cell.getCellType() Cell.CELL_TYPE_STRING) {return StringUtils.trimToEmpty(cell.getStringCellValue());} else if (cell.getCellType() Cell.CELL_TYPE_FORMULA) {return StringUtils.trimToEmpty(cell.getCellFormula());} else if (cell.getCellType() Cell.CELL_TYPE_BLANK) {return ;} else if (cell.getCellType() Cell.CELL_TYPE_BOOLEAN) {return StringUtils.trimToEmpty(cell.getBooleanCellValue());} else if (cell.getCellType() Cell.CELL_TYPE_ERROR) {return ERROR;} else {return cell.toString().trim;}}public static T void writeExcel(String filePathName, ListT dataList, ExcelRecordDynamicDTO excelRecordDTO) {Field[] fields excelRecordDTO.getClass().getDeclaredFields();ListField fieldList Arrays.stream(fields).filter(field - {ExcelColumn annotaion field.getAnnoation(ExcelColum.class);if (annotation ! null annotation.col() 0) {field.setAccessible(true);return true;}return false;}).sorted(Comparator.comparing(field - {int col 0;ExcelColumn annotation field.getAnnotation(ExcelColumn.class);if (annotation ! null) {col annotation.col();}return col;})).collect(Collectors.toList());Workbook wb new XSSFWorkbook();Sheet sheet wb.createSheet(Sheet1);AtomicInteger ai new AtomicInteger();{Row row sheet.createRow(ai.getAndIncrement());AtomicInteger aj new AtomicInteger();//写入头部fieldList.forEach(field - {ExcelColumn annotation field.getAnnotation(ExcelColumn.class);String columnName ;if (annotation ! null) {columnName annotation.value();}Cell cell row.createCell(aj.getAndIncreament());CellStyle cellStyle wb.createCellStyle();cellStyle.setFillForegroundColor(IndexedColors.WHITE.getIndex());cellSty;e.setFillPattern(CellStyle.SOLID_FOREGROUND);cellSty;e.setAlignment(CellStyle.ALIGN_CENTER);Font font wb.createFont();font.setBoldweight(Font.BOLDWEIGHT_NORMAL);cellStyle.setFont(font);cell.setCellStyle(cellStyle);cell.setCellValue(columnName);});}if (CollectionUtils.isNatEmpty(dataList)) {dataList.forEach(t - {Row row1 sheet.createRow(ai.getAndIncrement());AtomicInteger aj new AtomicInteger();fieldList.forEach(field - {Class? type field.getType();Object value ;try {value field.get(t);} catch (Exception e) {e.printStackTrace();}Cell cell row1.createCell(aj.getAndIncrement());if (value ! null) {if (type Date.class) {cell.setCellValue(value.toString());} else {cell.setCellValue(value.toString());}cell.setCellValue(value.toString());}});});}//冻结窗格wb.getSheet(Sheet1).createFreezePane(0, 1, 0, 1);//浏览器下载excel//buildExcelDocument(abbot.xlsx, wb, response);//生成Excel文件buildExcelFile(filePathName, wb);} private static void buildExcelFile(String path, Workbook wb) {File file new File(path);if (file.exists()) {file.delete();}try {wb.write(newFileOutputStream(file));} catch (Exception e) {e.printStackTrace();}}}
四.附
使用ClassPool动态生成类实测暂未解决的问题
1.无法给字段注解属性为int类型的赋值
2.只能一次创建无法清除上次动态创建的字段
代码如下 dependencygroupIdjavassist/groupIdartifactIdjavassist/artifactIdversion3.12.1.GA/version/dependencypublic Object getExcelRecordDynamicClass(ChatBatchRequestVO chatBatchRequest) throws NotFoundException, CannotCompileException, IllegalAccessException, InstantiationException {//默认的类搜索路径ClassPool pool ClassPool.getDefault();//获取一个ctClass对象 com.example.demo.excel.entity.CitiesVo 这个是包的相对路径
// CtClass ctClass pool.makeClass(ExcelRecordDynamicDTO);CtClass ctClass pool.get(cn.com.wind.ai.platform.aigc.test.pojo.excel.ExcelRecordDynamicDTO);for (int i 0; i chatBatchRequest.getModelTypeId().length; i) {//添加属性ctClass.addField(CtField.make(public String answer i ;, ctClass));//添加set方法ctClass.addMethod(CtMethod.make(public void setAnswer i (String answer i ){this.answer i answer i ;}, ctClass));//添加get方法ctClass.addMethod(CtMethod.make(public String getAnswer i (){return this.answer i ;}, ctClass));//获取这个字段CtField answer ctClass.getField(answer i);FieldInfo fieldInfo answer.getFieldInfo();ConstPool cp fieldInfo.getConstPool();AnnotationsAttribute attribute (AnnotationsAttribute) fieldInfo.getAttribute(AnnotationsAttribute.visibleTag);//这里进行了判断 如果说当前字段没有注解的时候 AnnotationsAttribute 这个对象是为空的//所以要针对这个进行新创建 一个 AnnotationsAttribute 对象if(ObjectUtils.isEmpty(attribute)){ListAttributeInfo attributeInfos fieldInfo.getAttributes();attribute !attributeInfos.isEmpty()?(AnnotationsAttribute) attributeInfos.get(0):new AnnotationsAttribute(fieldInfo.getConstPool(), AnnotationsAttribute.visibleTag);}// Annotation 默认构造方法 typeName:表示的是注解的路径Annotation bodyAnnot new Annotation(cn.com.wind.ai.platform.aigc.test.framework.aop.excel.ExcelColumn, cp);// name 表示的是自定义注解的 方法 new StringMemberValue(名字, cp) 表示给name赋值bodyAnnot.addMemberValue(value, new StringMemberValue(ChatModelTypeEnum.getmodelShowNameByType(chatBatchRequest.getModelTypeId()[i]), cp));
// IntegerMemberValue colValue new IntegerMemberValue(i 2, cp);
// bodyAnnot.addMemberValue(col, colValue);attribute.addAnnotation(bodyAnnot);fieldInfo.addAttribute(attribute);}pool.clearImportedPackages();return ctClass.toClass().newInstance();}
