Java操作Excel之POI的常用用法

待我称王封你为后i 2022-07-03 15:27 293阅读 0赞

1、创建一个带有头信息的Excel文件

public void testCreateExcelFile() throws Exception {
    		String fileName = "学生信息";
    		List<String> heads = new ArrayList<String>();
    		heads.add("学生ID");
    		heads.add("姓名");
    		heads.add("年龄");
    		heads.add("生日");
    		HSSFWorkbook createExcelFile = ExcelUtils.createExcelFile(fileName,heads);
    		OutputStream stream = new FileOutputStream(fileName + ".xls");
    		createExcelFile.write(stream);
    	}

![20170409170734682][]

2、创建一个带有头信息和数据的Excel文件

public void testcreateExcelFile() throws Exception {
    		String fileName = "学生信息";
    		List<String> heads = new ArrayList<String>();
    		heads.add("学生ID");
    		heads.add("姓名");
    		heads.add("年龄");
    		heads.add("生日");
    		// excel要填充的数据
    		List<List<String>> dataList = new ArrayList<List<String>>();
    		for (int i = 1; i <= 5; i++) {
    			List<String> rowData = new ArrayList<String>();
    			rowData.add("" + i);
    			rowData.add("" + i);
    			rowData.add("" + i);
    			//加入生日
    			rowData.add("2013-11-3");
    			// 加入到dataList里面
    			dataList.add(rowData);
    		}
    		HSSFWorkbook createExcelFile = ExcelUtils.createExcelFile(fileName,heads, dataList);
    		OutputStream stream = new FileOutputStream(fileName + ".xls");
    		createExcelFile.write(stream);
    	}

![20170409170757652][]

3、读取Excel文件到JavaBean的转换

public void testconvertExcelDataToClassData() throws Exception {
    		String fileName = "学生信息.xls";
    		Map<String, String> convertMap = new HashMap<String, String>();
    		convertMap.put("学生ID", "id");
    		convertMap.put("姓名", "name");
    		convertMap.put("年龄", "age");
    		convertMap.put("生日", "birthDay");
    		List<Student> students = ExcelUtils.convertExcelDataToClassData(convertMap, fileName, Student.class);
    		// 遍历输出结果
    		for (Student student : students) {
    			System.out.println(student);
    		}
    	}

![20170409170834696][]

![20170409170850481][]

4、读取Excel文件到JavaBean的转换(**带有主键性质，默认第一行为主键，当主键为空时，结束读取Excel数据**)

public void testconvertExcelDataToClassDataWithPrimaryKey()throws Exception {
    		String fileName = "学生信息.xls";
    		Map<String, String> convertMap = new HashMap<String, String>();
    		convertMap.put("学生ID", "id");
    		convertMap.put("姓名", "name");
    		convertMap.put("年龄", "age");
    		convertMap.put("生日", "birthDay");
    		List<Student> students = ExcelUtils.convertExcelDataToClassDataWithPrimaryKey(convertMap,fileName, Student.class);
    		// 遍历输出结果
    		for (Student student : students) {
    			System.out.println(student);
    		}
    	}

![20170409170925244][]

![20170409170938666][]

5、创建一个Excel文件,并填充其Sheet的名称和内容

public void testfillExcelWithSheetInfo() throws Exception {
    		String fileName = "学生信息";
    		// 模拟要填充的数据
    		// sheet的下标
    		int sheetNum = 0;
    		// sheet的名称
    		String[] sheetNameArr = { "高一一班", "高一二班" };
    		// 创建新的excel文件,以便于填充sheet数据
    		HSSFWorkbook workbook = ExcelUtils.createExcelFile();
    		// 模拟填充数据
    		for (String sheetName : sheetNameArr) {
    			//准备数据
    			// sheet信息
    			String sheetTitle = sheetName;
    			// 头信息
    			List<String> heads = new ArrayList<String>();
    			heads.add("学生ID");
    			heads.add("姓名");
    			heads.add("年龄");
    			heads.add("生日");
    			//dataList数据
    			List<List<String>> dataList = new ArrayList<List<String>>();
    			for (int i = 1; i < 5; i++) {
    				List<String> rowData = new ArrayList<String>();
    				rowData.add("" + i);
    				rowData.add("" + i);
    				rowData.add("" + i);
    				rowData.add("2013-3-11");
    				// 加入到dataList里面
    				dataList.add(rowData);
    			}
    			// 填充数据
    			ExcelUtils.fillExcelWithSheetInfo(workbook, sheetNum,
    					sheetTitle, heads, dataList);
    			// sheetNum++
    			sheetNum++;
    		}
    
    		// 输出excel文件
    		OutputStream stream = new FileOutputStream(fileName + ".xls");
    		workbook.write(stream);
    
    	}

![20170409170957619][]

6、根据List<JavaBean>结构来填充Excel显示的内容

public void testfillExcelData() throws Exception {
    		String fileName = "学生信息";
    		// 构造List<Student>,实际开发从数据库里面获取
    		List<Student> students = new ArrayList<Student>();
    		for (int i = 1; i < 5; i++) {
    			Student student = new Student();
    			student.setAge(i);
    			student.setName("" + i);
    			student.setId(i);
    			student.setBirthDay(new Date());
    			students.add(student);
    		}
    		Map<String, String> convertMap = new LinkedHashMap<String, String>();
    		convertMap.put("学生ID", "id");
    		convertMap.put("姓名", "name");
    		convertMap.put("年龄", "age");
    		convertMap.put("生日", "birthDay");
    		// 获取要填充的数据
    		Map<String, Object> excelData = ExcelUtils.fillExcelData(convertMap,students);
    		// 获取头信息
    		List<String> heads = (List<String>) excelData.get("heads");
    		// 获取数据信息
    		List<List<String>> dataList = (List<List<String>>) excelData.get("dataList");
    		// 创建Excel文件
    		HSSFWorkbook workbook = ExcelUtils.createExcelFile(fileName, heads,dataList);
    		// 输出Excel文件
    		OutputStream out = new FileOutputStream(fileName + ".xls");
    		workbook.write(out);
    	}

![20170409171016233][]

7、关于例子中用到的JavaBean的Student.java的实现

public class Student {
    	private int id;
    	private int age;
    	private String name;
    	private Date birthDay;
    }

8、关于ExcelUtils.java的实现代码

public class ExcelUtils {
    
    	/**
    	 * 
    	 * @Title: createExcelFile
    	 * @Description: 在填充sheet数据的时候,会需要一个空的Excel文件,用于设置Sheet信息的时候用到
    	 * @return 一个不带有头信息,数据信息的空的excel文件
    	 * @return: HSSFWorkbook
    	 */
    	public static HSSFWorkbook createExcelFile() {
    		HSSFWorkbook wb = new HSSFWorkbook();
    		return wb;
    	}
    
    	/**
    	 * 
    	 * @Title: createExcelFile
    	 * @Description: 创建一个空的带有头信息的excel
    	 * @param fileName
    	 * @param heads
    	 * @return
    	 * @return: HSSFWorkbook
    	 */
    	public static HSSFWorkbook createExcelFile(String fileName,
    			List<String> heads) {
    		HSSFWorkbook wb = new HSSFWorkbook();
    		if (StringUtils.isEmpty(fileName) || null == heads) {
    			return null;
    		} else {
    			HSSFSheet sheet = wb.createSheet(fileName);
    			HSSFRow row = sheet.createRow(0);
    			// 封装头信息
    			for (int index = 0; index < heads.size(); index++) {
    				row.createCell(index).setCellValue(heads.get(index));
    			}
    		}
    		return wb;
    	}
    
    	/**
    	 * @Title: createExcelFile
    	 * @Description: 创建excel,带有头信息和数据
    	 * @param fileName
    	 *            excel表格文件名称
    	 * @param heads
    	 *            excel表格的头信息
    	 * @param dataList
    	 *            excel表格要填充的数据
    	 * @return
    	 * @throws IOException
    	 * @return: HSSFWorkbook
    	 */
    	public static HSSFWorkbook createExcelFile(String fileName,
    			List<String> heads, List<List<String>> dataList) {
    		HSSFWorkbook wb = new HSSFWorkbook();
    		if (StringUtils.isEmpty(fileName) || null == heads || null == dataList) {
    			return null;
    		} else {
    			HSSFSheet sheet = wb.createSheet(fileName);
    			HSSFRow row = sheet.createRow(0);
    			// 封装头信息
    			for (int index = 0; index < heads.size(); index++) {
    				row.createCell(index).setCellValue(heads.get(index));
    			}
    			// 填充数据信息
    			for (int i = 0; i < dataList.size(); i++) {
    				HSSFRow row_data = sheet.createRow(i + 1);
    				for (int j = 0; j < dataList.get(i).size(); j++) {
    					row_data.createCell(j).setCellValue(dataList.get(i).get(j));
    				}
    			}
    		}
    		return wb;
    	}
    
    	/**
    	 * 
    	 * @Title: produceCellType
    	 * @Description: 获取excel单元格里面内容的格式,来获取数据
    	 * @param cell
    	 *            单元格
    	 * @return
    	 * @return: String 单元格的内容
    	 */
    	private static String produceCellType(Cell cell) {
    		String cellStrData = null;
    		if (null == cell) {
    			return null;
    		} else {
    			switch (cell.getCellType()) {
    			case HSSFCell.CELL_TYPE_NUMERIC: // 日期或者数字
    				// 处理日期格式、时间格式
    				if (HSSFDateUtil.isCellDateFormatted(cell)) {
    					SimpleDateFormat sdf = null;
    					// 时间格式的处理
    					if (cell.getCellStyle().getDataFormat() == HSSFDataFormat
    							.getBuiltinFormat("h:mm")) {
    						sdf = new SimpleDateFormat("HH:mm");
    					} else {// 日期格式的处理
    						sdf = new SimpleDateFormat("yyyy-MM-dd");
    					}
    					Date date = cell.getDateCellValue();
    					cellStrData = sdf.format(date);
    				} else {
    					// 数字的处理
    					double cellData = cell.getNumericCellValue();
    					cellStrData = String.valueOf(cellData);
    				}
    				break;
    			case HSSFCell.CELL_TYPE_STRING: // 字符串
    				cellStrData = cell.getStringCellValue();
    				break;
    			case HSSFCell.CELL_TYPE_BOOLEAN: // Boolean
    				cellStrData = String.valueOf(cell.getBooleanCellValue());
    				break;
    			case HSSFCell.CELL_TYPE_FORMULA: // 公式
    				cellStrData = String.valueOf(cell.getCellFormula());
    				break;
    			case HSSFCell.CELL_TYPE_BLANK: // 空值
    				break;
    			case HSSFCell.CELL_TYPE_ERROR: // 故障
    				break;
    			default:
    				break;
    			}
    		}
    		return cellStrData;
    	}
    
    	/**
    	 * 
    	 * @Title: convertExcelDataToMapDataWithPrimaryKey
    	 * @Description: 将excel文件的每一行数据,转换为HashMap的形式.只转换第一个sheet的数据内容
    	 * @param convertMap
    	 *            转换的准则,例如 Map<String, String> headMap = new
    	 *            LinkedHashMap<String, String>(); headMap.put("指标ID",
    	 *            "indicatorId"); headMap.put("指标名称", "indicatorName");
    	 * @param filePath
    	 *            excel文件
    	 * @return
    	 * @throws IOException
    	 * @return: List<HashMap<String, String>>
    	 */
    	public static List<HashMap<String, String>> convertExcelDataToMapData(
    			Map<String, String> convertMap, String filePath) throws IOException {
    		List<HashMap<String, String>> dataList = new ArrayList<HashMap<String, String>>();
    		Map<String, Integer> headMap = new HashMap<String, Integer>();
    		if (null == convertMap || convertMap.size() == 0
    				|| StringUtils.isEmpty(filePath)) {
    			return dataList;
    		} else {
    			InputStream input = new FileInputStream(filePath); // 建立输入流
    			Workbook wb = new HSSFWorkbook(input);
    			Sheet sheet = wb.getSheetAt(0);
    			Row rowIndexs = sheet.getRow(0);
    			int cellSize = rowIndexs.getLastCellNum();
    			Set<String> keys = convertMap.keySet();
    			// 将对应的字段和excel的head的下标对应起来
    			for (String key : keys) {
    				for (int i = 0; i < cellSize; i++) {
    					Cell cell = rowIndexs.getCell(i);
    					if (cell != null
    							&& cell.getCellType() != Cell.CELL_TYPE_BLANK) {
    						if (key.equals(cell.getStringCellValue())) {
    							headMap.put(key, rowIndexs.getCell(i)
    									.getColumnIndex());
    						}
    					}
    				}
    			}
    			// 处理数据
    			int rowSize = sheet.getLastRowNum();
    			for (int i = 1; i < rowSize; i++) { // 第一行默认是表头数据,不算入计算结果
    				HashMap<String, String> resultMap = new HashMap<String, String>(); // 用于保存每一行的转换结果
    				Row row = sheet.getRow(i);
    				for (Entry<String, Integer> entry : headMap.entrySet()) {
    					Cell cell = row.getCell(entry.getValue());
    					String data = produceCellType(cell);
    					resultMap.put(convertMap.get(entry.getKey()), data);
    				}
    				dataList.add(resultMap);
    			}
    		}
    
    		return dataList;
    	}
    
    	/**
    	 * 
    	 * @Title: convertExcelDataToMapDataWithPrimaryKey
    	 * @Description: excel的转换,带有主键的原则。如果excel的那一行数据的表示的主键为null或者没填写。那么这一行不转换。
    	 *               例如,下面的 指标ID可以理解为主键.//默认第一行的第一列为主键
    	 *               将excel文件的每一行数据,转换为HashMap的形式.只转换第一个sheet的数据内容.
    	 * @param convertMap
    	 *            转换的准则,例如 Map<String, String> headMap = new
    	 *            LinkedHashMap<String, String>(); headMap.put("指标ID",
    	 *            "indicatorId"); headMap.put("指标名称", "indicatorName");
    	 * @param filePath
    	 *            excel文件
    	 * @return
    	 * @throws IOException
    	 * @return: List<HashMap<String, String>>
    	 */
    	public static List<HashMap<String, String>> convertExcelDataToMapDataWithPrimaryKey(
    			Map<String, String> convertMap, String filePath) throws IOException {
    		List<HashMap<String, String>> dataList = new ArrayList<HashMap<String, String>>();
    		Map<String, Integer> headMap = new HashMap<String, Integer>();
    		if (null == convertMap || convertMap.size() == 0
    				|| StringUtils.isEmpty(filePath)) {
    			return dataList;
    		} else {
    			InputStream input = new FileInputStream(filePath); // 建立输入流
    			Workbook wb = new HSSFWorkbook(input);
    			Sheet sheet = wb.getSheetAt(0);
    			Row rowIndexs = sheet.getRow(0);
    			int cellSize = rowIndexs.getLastCellNum();
    			Set<String> keys = convertMap.keySet();
    			// 将对应的字段和excel的head的下标对应起来
    			for (String key : keys) {
    				for (int i = 0; i < cellSize; i++) {
    					Cell cell = rowIndexs.getCell(i);
    					if (cell != null
    							&& cell.getCellType() != Cell.CELL_TYPE_BLANK) {
    						if (key.equals(cell.getStringCellValue())) {
    							headMap.put(key, rowIndexs.getCell(i)
    									.getColumnIndex());
    						}
    					}
    				}
    			}
    			// 处理数据
    			int rowSize = sheet.getLastRowNum();
    			for (int i = 1; i < rowSize; i++) { // 第一行默认是表头数据,不算入计算结果
    				HashMap<String, String> resultMap = new HashMap<String, String>(); // 用于保存每一行的转换结果
    				Row row = sheet.getRow(i);
    				Cell flagCell = row.getCell(0); // 默认第0列是每一行的主键
    				if (null != row && null != flagCell
    						&& HSSFCell.CELL_TYPE_BLANK != flagCell.getCellType()) {
    					for (Entry<String, Integer> entry : headMap.entrySet()) {
    						Cell cell = row.getCell(entry.getValue());
    						if (null != cell) {
    							String data = produceCellType(cell);
    							resultMap.put(convertMap.get(entry.getKey()), data);
    						}
    					}
    				}
    				// 将数据加入到,返回数值里面
    				dataList.add(resultMap);
    			}
    		}
    		return dataList;
    	}
    
    	/**
    	 * @param <T>
    	 * @Title: convertExcelDataToClassData
    	 * @Description: 解析excel已有的数据,以Class的形式返回.
    	 * @param headNameMap
    	 *            headNameMap.put("CID", "customerId")
    	 * @param fileName
    	 *            excel文件
    	 * @param class1
    	 *            要转换的Class的类型
    	 * @return
    	 * @throws InstantiationException
    	 * @throws IllegalAccessException
    	 * @throws IOException
    	 * @throws NoSuchFieldException
    	 * @throws SecurityException
    	 * @return: List<T>
    	 */
    	public static <T> List<T> convertExcelDataToClassData(
    			Map<String, String> convertMap, String fileName, Class<T> class1)
    			throws InstantiationException, IllegalAccessException, IOException,
    			NoSuchFieldException, SecurityException {
    
    		List<T> objects = new ArrayList<T>(); // 返回结果集
    		Map<String, Integer> indexHashMap = new HashMap<String, Integer>(); // 定位excel头文件cell位置
    		if (null == convertMap || convertMap.size() == 0
    				|| StringUtils.isEmpty(fileName)) {
    			return objects;
    		} else {
    			InputStream input = new FileInputStream(fileName); // 建立输入流
    			Workbook wb = new HSSFWorkbook(input);
    			Sheet sheet = wb.getSheetAt(0);
    			Row rowIndexs = sheet.getRow(0);
    			int cellSize = rowIndexs.getLastCellNum();
    			// 将对应的字段和excel的head的下标对应起来
    			Set<String> keys = convertMap.keySet();
    			for (String key : keys) {
    				for (int i = 0; i < cellSize; i++) {
    					Cell cell = rowIndexs.getCell(i);
    					if (cell != null
    							&& cell.getCellType() != Cell.CELL_TYPE_BLANK) {
    						if (key.equals(produceCellType(cell))) {
    							indexHashMap.put(key, rowIndexs.getCell(i)
    									.getColumnIndex()); // 头文件push 下标位置
    						}
    					}
    				}
    			}
    			// 数据的封装
    			for (int i = 1; i <= sheet.getLastRowNum(); i++) { // 第一行默认是下标，不算入计算结果
    				Row row = sheet.getRow(i);
    				T object = class1.newInstance();
    				for (Entry<String, Integer> entry : indexHashMap.entrySet()) {
    					Cell cell = row.getCell(entry.getValue());
    					String data = produceCellType(cell);
    					String fieldName = convertMap.get(entry.getKey());
    					Field field = object.getClass().getDeclaredField(fieldName);
    					field.setAccessible(true);
    					// 根据Field的类型,来设置Field的内容
    					// 以便于适应除了String外的int,long,double,float等类型的属性
    					setFieldValue(object, data, field);
    				}
    				objects.add(object);
    			}
    
    		}
    		return objects;
    	}
    
    	/**
    	 * @param <T>
    	 * @Title: convertExcelDataToClassData
    	 * @Description: 解析excel已有的数据,以Class的形式返回.
    	 * @param headNameMap
    	 *            headNameMap.put("CID", "customerId")
    	 * @param fileName
    	 *            excel文件
    	 * @param class1
    	 *            要转换的Class的类型
    	 * @return
    	 * @throws InstantiationException
    	 * @throws IllegalAccessException
    	 * @throws IOException
    	 * @throws NoSuchFieldException
    	 * @throws SecurityException
    	 * @return: List<T>
    	 */
    	public static <T> List<T> convertExcelDataToClassData(
    			Map<String, String> convertMap, InputStream input, Class<T> class1)
    			throws InstantiationException, IllegalAccessException, IOException,
    			NoSuchFieldException, SecurityException {
    
    		List<T> objects = new ArrayList<T>(); // 返回结果集
    		Map<String, Integer> indexHashMap = new HashMap<String, Integer>(); // 定位excel头文件cell位置
    		if (null == convertMap || convertMap.size() == 0 || null == input) {
    			return objects;
    		} else {
    			Workbook wb = new HSSFWorkbook(input);
    			Sheet sheet = wb.getSheetAt(0);
    			Row rowIndexs = sheet.getRow(0);
    			int cellSize = rowIndexs.getLastCellNum();
    			// 将对应的字段和excel的head的下标对应起来
    			Set<String> keys = convertMap.keySet();
    			for (String key : keys) {
    				for (int i = 0; i < cellSize; i++) {
    					Cell cell = rowIndexs.getCell(i);
    					if (cell != null
    							&& cell.getCellType() != Cell.CELL_TYPE_BLANK) {
    						if (key.equals(produceCellType(cell))) {
    							indexHashMap.put(key, rowIndexs.getCell(i)
    									.getColumnIndex()); // 头文件push 下标位置
    						}
    					}
    				}
    			}
    			// 数据的封装
    			for (int i = 1; i <= sheet.getLastRowNum(); i++) { // 第一行默认是下标，不算入计算结果
    				Row row = sheet.getRow(i);
    				T object = class1.newInstance();
    				for (Entry<String, Integer> entry : indexHashMap.entrySet()) {
    					Cell cell = row.getCell(entry.getValue());
    					String data = produceCellType(cell);
    					String fieldName = convertMap.get(entry.getKey());
    					Field field = object.getClass().getDeclaredField(fieldName);
    					field.setAccessible(true);
    					// 根据Field的类型,来设置Field的内容
    					// 以便于适应除了String外的int,long,double,float等类型的属性
    					setFieldValue(object, data, field);
    				}
    				objects.add(object);
    			}
    
    		}
    		return objects;
    	}
    
    	/**
    	 * @Title: matcheExcelIndexToDataForm
    	 * @Description: 解析excel已数组的形式返回
    	 * @param headNameMap
    	 *            headNameMap.put("CID", "customerId")
    	 * @param fileName
    	 * @param class1
    	 * @return
    	 * @throws InstantiationException
    	 * @throws IllegalAccessException
    	 * @throws IOException
    	 * @throws NoSuchFieldException
    	 * @throws SecurityException
    	 * @return: List<Object>
    	 */
    	public static <T> List<T> convertExcelDataToClassDataWithPrimaryKey(
    			Map<String, String> headNameMap, InputStream ips, Class<T> class1)
    			throws InstantiationException, IllegalAccessException, IOException,
    			NoSuchFieldException, SecurityException {
    
    		List<T> objects = new ArrayList<T>(); // 返回结果集
    		Map<String, Integer> indexHashMap = new HashMap<String, Integer>(); // 定位excel头文件cell位置
    		if (null == headNameMap || headNameMap.size() == 0 || null == ips) {
    			return objects;
    		} else {
    			Workbook wb = null;
    			wb = new HSSFWorkbook(ips);
    			Sheet sheet = wb.getSheetAt(0);
    			Row rowIndexs = sheet.getRow(0);
    			int cellSize = rowIndexs.getLastCellNum();
    			Set<String> keys = headNameMap.keySet();
    			for (String key : keys) {
    				for (int i = 0; i < cellSize; i++) {
    					Cell cell = rowIndexs.getCell(i);
    					if (cell != null
    							&& cell.getCellType() != Cell.CELL_TYPE_BLANK) {
    						if (key.equals(cell.getStringCellValue())) {
    							indexHashMap.put(key, rowIndexs.getCell(i)
    									.getColumnIndex()); // 头文件push 下标位置
    						}
    
    					}
    
    				}
    			}
    
    			for (int i = 1; i <= sheet.getLastRowNum(); i++) { // 第一行默认是下标，不算入计算结果
    				Row row = sheet.getRow(i);
    				T object = class1.newInstance();
    				Cell flagCell = row.getCell(0);
    				if (null != row && null != flagCell
    						&& HSSFCell.CELL_TYPE_BLANK != flagCell.getCellType()) {
    					for (Entry<String, Integer> entry : indexHashMap.entrySet()) {
    						Cell cell = row.getCell(entry.getValue());
    						if (null != cell) {
    							String data = produceCellType(cell);
    							String fieldName = headNameMap.get(entry.getKey());
    							Field field = object.getClass().getDeclaredField(
    									fieldName);
    							field.setAccessible(true);
    							// 根据Field的类型,来设置Field的内容
    							// 以便于适应除了String外的int,long,double,float等类型的属性
    							setFieldValue(object, data, field);
    						} else {
    							continue;
    						}
    					}
    					objects.add(object);
    				} else {
    					break;
    				}
    			}
    
    		}
    		return objects;
    	}
    
    	/**
    	 * 
    	 * @Title: setFieldValue 设置JavaBean属性的数据,以便于支持除了String类型外的其他数据类型
    	 * @Description: setFieldValue
    	 *               设置JavaBean属性的数据,以便于支持除了String类型外的其他数据类型,例如int,
    	 *               long,double,date
    	 * @param object
    	 *            JavaBean
    	 * @param data
    	 *            要设置的数据
    	 * @param field
    	 *            JavaBean的Field字段
    	 * @throws IllegalAccessException
    	 * @return: void
    	 */
    	private static <T> void setFieldValue(T object, String data, Field field)
    			throws IllegalAccessException {
    		// 对field的类型进行判断,以便于支持String外的其它类型
    		String fieldType = field.getType().getName();
    		if (fieldType.equals("java.lang.Double") || fieldType.equals("double")) {
    			// Double类型的处理
    			double doubleValue = Double.parseDouble(data);
    			field.set(object, doubleValue);
    		} else if (fieldType.equals("java.lang.Float")
    				|| fieldType.equals("float")) {
    			// Float类型的处理
    			float folatValue = Float.parseFloat(data);
    			field.set(object, folatValue);
    		} else if (fieldType.equals("java.lang.Integer")
    				|| fieldType.equals("int")) {
    			// Integer类型的处理
    			int intValue = Integer.parseInt(data);
    			field.set(object, intValue);
    		} else if (fieldType.equals("java.lang.Long")
    				|| fieldType.equals("long")) {
    			// Long类型的处理
    			long longValue = Long.parseLong(data);
    			field.set(object, longValue);
    		} else if (field.getType().getName().equals("java.util.Date")) {
    			// Date类型的处理
    			// "yyyy-MM-dd HH:mm:ss",根据具体的格式来处理
    			Date dateValue = strToDate(data);
    			field.set(object, dateValue);
    		} else {
    			// String的处理
    			field.set(object, data);
    		}
    	}
    
    	/**
    	 * @Title: matcheExcelIndexToDataForm
    	 * @Description: 解析excel已数组的形式返回
    	 * @param headNameMap
    	 *            headNameMap.put("CID", "customerId")
    	 * @param fileName
    	 * @param class1
    	 * @return
    	 * @throws InstantiationException
    	 * @throws IllegalAccessException
    	 * @throws IOException
    	 * @throws NoSuchFieldException
    	 * @throws SecurityException
    	 * @return: List<Object>
    	 */
    	public static <T> List<T> convertExcelDataToClassDataWithPrimaryKey(
    			Map<String, String> headNameMap, String fileName, Class<T> class1)
    			throws InstantiationException, IllegalAccessException, IOException,
    			NoSuchFieldException, SecurityException {
    
    		List<T> objects = new ArrayList<T>(); // 返回结果集
    		Map<String, Integer> indexHashMap = new HashMap<String, Integer>(); // 定位excel头文件cell位置
    		if (null == headNameMap || headNameMap.size() == 0 || null == fileName) {
    			return objects;
    		} else {
    			Workbook wb = null;
    			InputStream ips = new FileInputStream(fileName);
    			wb = new HSSFWorkbook(ips);
    			Sheet sheet = wb.getSheetAt(0);
    			Row rowIndexs = sheet.getRow(0);
    			int cellSize = rowIndexs.getLastCellNum();
    			Set<String> keys = headNameMap.keySet();
    			for (String key : keys) {
    				for (int i = 0; i < cellSize; i++) {
    					Cell cell = rowIndexs.getCell(i);
    					if (cell != null
    							&& cell.getCellType() != Cell.CELL_TYPE_BLANK) {
    						if (key.equals(cell.getStringCellValue())) {
    							indexHashMap.put(key, rowIndexs.getCell(i)
    									.getColumnIndex()); // 头文件push 下标位置
    						}
    
    					}
    
    				}
    			}
    
    			for (int i = 1; i <= sheet.getLastRowNum(); i++) { // 第一行默认是下标，不算入计算结果
    				Row row = sheet.getRow(i);
    				T object = class1.newInstance();
    				Cell flagCell = row.getCell(0);
    				if (null != row && null != flagCell
    						&& HSSFCell.CELL_TYPE_BLANK != flagCell.getCellType()) {
    					for (Entry<String, Integer> entry : indexHashMap.entrySet()) {
    						Cell cell = row.getCell(entry.getValue());
    						if (null != cell) {
    							String data = produceCellType(cell);
    							String fieldName = headNameMap.get(entry.getKey());
    							Field field = object.getClass().getDeclaredField(
    									fieldName);
    							field.setAccessible(true);
    							// 根据Field的类型,来设置Field的内容
    							// 以便于适应除了String外的int,long,double,float等类型的属性
    							setFieldValue(object, data, field);
    						} else {
    							continue;
    						}
    					}
    					objects.add(object);
    				} else {
    					break;
    				}
    			}
    
    		}
    		return objects;
    	}
    
    	/**
    	 * 
    	 * @Title: exportExcel
    	 * @Description: 需要先创建好excel文件,调用一次添加一次sheet信息
    	 * @param workbook
    	 *            要添加sheet信息的excel
    	 * @param sheetNum
    	 *            sheet的编号位置,从0开始
    	 * @param sheetTitle
    	 *            要添加sheet信息
    	 * @param heads
    	 *            头信息
    	 * @param dataList
    	 *            要填充的数据
    	 * @return
    	 * @throws Exception
    	 * @return: HSSFWorkbook 返回天填充数据后的excel
    	 */
    	public static HSSFWorkbook fillExcelWithSheetInfo(HSSFWorkbook workbook,
    			int sheetNum, String sheetTitle, List<String> heads,
    			List<List<String>> dataList) throws IOException {
    		if (StringUtils.isEmpty(sheetTitle) || null == heads
    				|| null == dataList || workbook == null) {
    			return null;
    		} else {
    			// create sheet
    			HSSFSheet sheet = workbook.createSheet();
    			workbook.setSheetName(sheetNum, sheetTitle);
    			// 头信息
    			HSSFRow row = sheet.createRow(0);
    			for (int index = 0; index < heads.size(); index++) {
    				row.createCell(index).setCellValue(heads.get(index));
    			}
    			// 填充信息
    			for (int i = 0; i < dataList.size(); i++) {
    				HSSFRow row_data = sheet.createRow(i + 1);
    				for (int j = 0; j < dataList.get(i).size(); j++) {
    					row_data.createCell(j).setCellValue(dataList.get(i).get(j));
    				}
    			}
    		}
    		return workbook;
    	}
    
    	/**
    	 * 使用一个List数组,来填充要显示的excel数据
    	 * 
    	 * @param userList
    	 *            headMap.put("顾问ID", "userId");
    	 * @return
    	 * @throws NoSuchFieldException
    	 * @throws SecurityException
    	 * @throws IllegalArgumentException
    	 * @throws IllegalAccessException
    	 */
    	public static Map<String, Object> fillExcelData(
    			Map<String, String> headMap, List<?> objects)
    			throws NoSuchFieldException, SecurityException,
    			IllegalArgumentException, IllegalAccessException {
    		Map<String, Object> resMap = new HashMap<String, Object>();
    		List<String> heads = new ArrayList<String>();
    		Set<String> keySet = headMap.keySet();
    		List<List<String>> dataList = new ArrayList<List<String>>();
    		boolean flag = true;
    		if (null == objects || objects.size() < 1) {
    			for (String key : keySet) {
    				heads.add(key);
    			}
    		}
    		for (Object object : objects) {
    			List<String> data = new ArrayList<String>();
    			for (String key : keySet) {
    				if (flag == true) {
    					heads.add(key);
    				}
    				Field userField = object.getClass().getDeclaredField(
    						headMap.get(key));
    				userField.setAccessible(true);
    				String userData = String.valueOf(userField.get(object));
    				// 一些特殊的判断
    				if ("状态".equals(key)) {
    					if ("1".equals(userData)) {
    						userData = "有效";
    					} else {
    						userData = "无效";
    					}
    				}
    				data.add(userData);
    			}
    			flag = false;
    			dataList.add(data);
    		}
    		resMap.put("heads", heads);
    		resMap.put("dataList", dataList);
    		return resMap;
    	}
    
    	/**
    	 * 将长时间格式字符串转换为时间 yyyy-MM-dd HH:mm:ss
    	 * 
    	 * @param strDate
    	 * @return
    	 */
    	private static Date strToDate(String strDate) {
    		SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd");
    		ParsePosition pos = new ParsePosition(0);
    		Date strtodate = formatter.parse(strDate, pos);
    		return strtodate;
    	}
    
    }

9、完整的测试代码

import java.io.FileOutputStream;
    import java.io.OutputStream;
    import java.util.ArrayList;
    import java.util.Date;
    import java.util.HashMap;
    import java.util.LinkedHashMap;
    import java.util.List;
    import java.util.Map;
    
    import org.apache.poi.hssf.usermodel.HSSFWorkbook;
    import org.junit.Test;
    
    import com.baowei.util.ExcelUtils;
    
    import entity.Student;
    
    public class TestExcelUtils {
    
    	@Test
    	public void testCreateExcelFile() throws Exception {
    		String fileName = "学生信息";
    		List<String> heads = new ArrayList<String>();
    		heads.add("学生ID");
    		heads.add("姓名");
    		heads.add("年龄");
    		heads.add("生日");
    		HSSFWorkbook createExcelFile = ExcelUtils.createExcelFile(fileName,
    				heads);
    		OutputStream stream = new FileOutputStream(fileName + ".xls");
    		createExcelFile.write(stream);
    	}
    
    	@Test
    	public void testcreateExcelFile() throws Exception {
    		String fileName = "学生信息";
    		List<String> heads = new ArrayList<String>();
    		heads.add("学生ID");
    		heads.add("姓名");
    		heads.add("年龄");
    		heads.add("生日");
    		// excel要填充的数据
    		List<List<String>> dataList = new ArrayList<List<String>>();
    		for (int i = 1; i <= 5; i++) {
    			List<String> rowData = new ArrayList<String>();
    			rowData.add("" + i);
    			rowData.add("" + i);
    			rowData.add("" + i);
    			// 加入生日
    			rowData.add("2013-11-3");
    			// 加入到dataList里面
    			dataList.add(rowData);
    		}
    		HSSFWorkbook createExcelFile = ExcelUtils.createExcelFile(fileName,
    				heads, dataList);
    		OutputStream stream = new FileOutputStream(fileName + ".xls");
    		createExcelFile.write(stream);
    	}
    
    	@Test
    	public void testconvertExcelDataToClassData() throws Exception {
    		String fileName = "学生信息.xls";
    		Map<String, String> convertMap = new HashMap<String, String>();
    		convertMap.put("学生ID", "id");
    		convertMap.put("姓名", "name");
    		convertMap.put("年龄", "age");
    		convertMap.put("生日", "birthDay");
    		List<Student> students = ExcelUtils.convertExcelDataToClassData(
    				convertMap, fileName, Student.class);
    		// 遍历输出结果
    		for (Student student : students) {
    			System.out.println(student);
    		}
    	}
    
    	@Test
    	public void testconvertExcelDataToClassDataWithPrimaryKey()
    			throws Exception {
    		String fileName = "学生信息.xls";
    		Map<String, String> convertMap = new HashMap<String, String>();
    		convertMap.put("学生ID", "id");
    		convertMap.put("姓名", "name");
    		convertMap.put("年龄", "age");
    		convertMap.put("生日", "birthDay");
    		List<Student> students = ExcelUtils
    				.convertExcelDataToClassDataWithPrimaryKey(convertMap,
    						fileName, Student.class);
    		// 遍历输出结果
    		for (Student student : students) {
    			System.out.println(student);
    		}
    	}
    
    	@Test
    	public void testfillExcelWithSheetInfo() throws Exception {
    		String fileName = "学生信息";
    		// 模拟要填充的数据
    		// sheet的下标
    		int sheetNum = 0;
    		// sheet的名称
    		String[] sheetNameArr = { "高一一班", "高一二班" };
    		// 创建新的excel文件,以便于填充sheet数据
    		HSSFWorkbook workbook = ExcelUtils.createExcelFile();
    		// 模拟填充数据
    		for (String sheetName : sheetNameArr) {
    			// 准备数据
    			// sheet信息
    			String sheetTitle = sheetName;
    			// 头信息
    			List<String> heads = new ArrayList<String>();
    			heads.add("学生ID");
    			heads.add("姓名");
    			heads.add("年龄");
    			heads.add("生日");
    			// dataList数据
    			List<List<String>> dataList = new ArrayList<List<String>>();
    			for (int i = 1; i < 5; i++) {
    				List<String> rowData = new ArrayList<String>();
    				rowData.add("" + i);
    				rowData.add("" + i);
    				rowData.add("" + i);
    				rowData.add("2013-3-11");
    				// 加入到dataList里面
    				dataList.add(rowData);
    			}
    			// 填充数据
    			ExcelUtils.fillExcelWithSheetInfo(workbook, sheetNum, sheetTitle,
    					heads, dataList);
    			// sheetNum++
    			sheetNum++;
    		}
    
    		// 输出excel文件
    		OutputStream stream = new FileOutputStream(fileName + ".xls");
    		workbook.write(stream);
    	}
    
    	@SuppressWarnings("unchecked")
    	@Test
    	public void testfillExcelData() throws Exception {
    		String fileName = "学生信息";
    		// 构造List<Student>,实际开发从数据库里面获取
    		List<Student> students = new ArrayList<Student>();
    		for (int i = 1; i < 5; i++) {
    			Student student = new Student();
    			student.setAge(i);
    			student.setName("" + i);
    			student.setId(i);
    			student.setBirthDay(new Date());
    			students.add(student);
    		}
    		Map<String, String> convertMap = new LinkedHashMap<String, String>();
    		convertMap.put("学生ID", "id");
    		convertMap.put("姓名", "name");
    		convertMap.put("年龄", "age");
    		convertMap.put("生日", "birthDay");
    		// 获取要填充的数据
    		Map<String, Object> excelData = ExcelUtils.fillExcelData(convertMap,students);
    		// 获取头信息
    		List<String> heads = (List<String>) excelData.get("heads");
    		// 获取数据信息
    		List<List<String>> dataList = (List<List<String>>) excelData.get("dataList");
    		// 创建Excel文件
    		HSSFWorkbook workbook = ExcelUtils.createExcelFile(fileName, heads,dataList);
    		// 输出Excel文件
    		OutputStream out = new FileOutputStream(fileName + ".xls");
    		workbook.write(out);
    	}
    
    	
    }

10、[源码下载][Link 1]

[20170409170734682]: /images/20220618/7ba087adf1be4775b2a42df084cb9211.png
[20170409170757652]: /images/20220618/d35540f1c6024cfb8f352b5bb9ed44e7.png
[20170409170834696]: /images/20220618/72f99ab4f0d44f0c9b84624c2ed24692.png
[20170409170850481]: /images/20220618/e6e691ae5d7445aabbb9ea23c6134423.png
[20170409170925244]: /images/20220618/a49d2bb8aacf41aeb34186b81fc155d7.png
[20170409170938666]: /images/20220618/c9737e7dd9ad4b56810d21140dd15381.png
[20170409170957619]: /images/20220618/cc0b0b018284414894388a551d39094d.png
[20170409171016233]: /images/20220618/dd89764634c94837a1a0d9143bc7d1ab.png
[Link 1]: https://git.oschina.net/baowei/My_JavaScript/blob/master/poi.zip?dir=0&filepath=poi.zip&oid=a15237a05021105c5b570be5e202482f5d9ab6e0&sha=45c4e0ff526fde8d995b59d49333640d93351f7d