java 注解方式 写入数据到Excel文件中

之前有写过一点关于java实现写Excel文件的方法，但是现在看来，那种方式用起来不是太舒服，还很麻烦。所以最近又参考其他，就写了一个新版，用起来不要太爽。

代码不需要解释，惯例直接贴下来：

  1 public class ExcelExport implements Closeable {
  2 
  3     private static final Logger LOGGER = LoggerFactory.getLogger(ExcelExport.class);
  4 
  5     public static final String EXCEL_SUFFIX = ".xlsx"; // 目前只支持xlsx格式
  6 
  7     private static final String SHEET_FONT_TYPE = "Arial";
  8 
  9     private Workbook workbook;
 10 
 11     private Sheet sheet;
 12 
 13     private int rowNum;
 14 
 15     private Map styles;
 16 
 17     private List columns;
 18 
 19     public ExcelExport createSheet(String sheetName, String title, Class clazz) throws Exception {
 20         this.workbook = createWorkbook();
 21         this.columns = createColumns();
 22         Field[] fields = clazz.getDeclaredFields();
 23         for (Field field : fields) {
 24             ExcelField excelField = field.getAnnotation(ExcelField.class);
 25             if (excelField != null) {
 26                 this.columns.add(new ColumnField(excelField.title(), field.getName(), field.getType(), excelField.width()));
 27             }
 28         }
 29         if (CollectionUtils.isEmpty(this.columns)) throw new Exception("Excel's headerList are undefined");
 30         this.sheet = workbook.createSheet(StringUtils.defaultString(sheetName, StringUtils.defaultString(title, "Sheet1")));
 31         this.styles = createStyles(workbook);
 32         this.rowNum = 0;
 33         if (StringUtils.isNotBlank(title)) {
 34             Row titleRow = sheet.createRow(rowNum++);
 35             titleRow.setHeightInPoints(30);
 36             Cell titleCell = titleRow.createCell(0);
 37             titleCell.setCellStyle(styles.get("title"));
 38             titleCell.setCellValue(title);
 39             sheet.addMergedRegion(new CellRangeAddress(titleRow.getRowNum(), titleRow.getRowNum(), titleRow.getRowNum(),
 40                     this.columns.size() - 1));
 41         }
 42         Row headerRow = sheet.createRow(rowNum++);
 43         headerRow.setHeightInPoints(16);
 44         for (int i = 0; i < this.columns.size(); i++) {
 45             int width = this.columns.get(i).width;
 46             this.sheet.setColumnWidth(i, 256 * width + 184);
 47             Cell cell = headerRow.createCell(i);
 48             cell.setCellStyle(styles.get("header"));
 49             cell.setCellValue(this.columns.get(i).title);
 50         }
 51         return this;
 52     }
 53 
 54     public  ExcelExport setDataList(List dataList) throws IllegalAccessException {
 55         for (E data : dataList) {
 56             int column = 0;
 57             Row row = this.addRow();
 58             Map map = toMap(data);
 59             for (ColumnField field : this.columns) {
 60                 Class paramType = field.getParamType();
 61                 if (map.containsKey(field.getParam())) {
 62                     Object value = map.get(field.getParam());
 63                     this.addCell(row, column++, value, paramType);
 64                 }
 65             }
 66         }
 67         LOGGER.debug("add data into {} success", this.sheet.getSheetName());
 68         return this;
 69     }
 70 
 71     private Cell addCell(Row row, int column, Object value, Class type) {
 72         Cell cell = row.createCell(column);
 73         if (value == null) {
 74             cell.setCellValue("");
 75         } else if (type.isAssignableFrom(String.class)) {
 76             cell.setCellValue((String) value);
 77         } else if (type.isAssignableFrom(Integer.class)) {
 78             cell.setCellValue((Integer) value);
 79         } else if (type.isAssignableFrom(Double.class)) {
 80             cell.setCellValue((Double) value);
 81         } else if (type.isAssignableFrom(Long.class)) {
 82             cell.setCellValue((Long) value);
 83         } else if (type.isAssignableFrom(Float.class)) {
 84             cell.setCellValue((Float) value);
 85         } else if (type.isAssignableFrom(Date.class)) {
 86             Date time = (Date) value;
 87             String timer = DateUtils.formatDate(time, "yyyy-MM-dd HH:mm:ss");
 88             cell.setCellValue(timer);
 89         } else {
 90             cell.setCellValue(Objects.toString(value));
 91         }
 92         cell.setCellStyle(styles.get("data"));
 93         return cell;
 94     }
 95 
 96     private Map toMap(Object entity) throws IllegalAccessException {
 97         Map row = Maps.newHashMap();
 98         if (null == entity) return row;
 99         Class clazz = entity.getClass();
100         Field[] fields = clazz.getDeclaredFields();
101         for (Field field : fields) {
102             field.setAccessible(true);
103             row.put(field.getName(), field.get(entity));
104         }
105         return row;
106     }
107 
108     private Row addRow() {
109         return sheet.createRow(rowNum++);
110     }
111 
112     public ExcelExport write(OutputStream os) {
113         try {
114             workbook.write(os);
115         } catch (IOException ex) {
116             LOGGER.error(ex.getMessage(), ex);
117         } finally {
118             if (null != os) {
119                 try {
120                     os.close();
121                 } catch (IOException e) {
122                     LOGGER.error("close Output Stream failed: {}", e.getMessage());
123                 }
124             }
125         }
126         return this;
127     }
128 
129     public ExcelExport write(HttpServletResponse response, String fileName) {
130         response.reset();
131         try {
132             response.setContentType("application/octet-stream; charset=utf-8");
133             response.setHeader("Content-Disposition", "attachment; filename=" + URLEncoder.encode(fileName, UTF8));
134             write(response.getOutputStream());
135         } catch (IOException ex) {
136             LOGGER.error(ex.getMessage(), ex);
137         }
138         return this;
139     }
140 
141     public ExcelExport writeFile(String name) throws IOException {
142         FileOutputStream os = new FileOutputStream(name);
143         this.write(os);
144         return this;
145     }
146 
147     private Workbook createWorkbook() {
148         return new SXSSFWorkbook();
149     }
150 
151     private List createColumns() {
152         return Lists.newLinkedList();
153     }
154 
155     private Map createStyles(Workbook workbook) {
156         Map styleMap = Maps.newHashMap();
157 
158         CellStyle style = workbook.createCellStyle();
159         style.setAlignment(HorizontalAlignment.CENTER);
160         style.setVerticalAlignment(VerticalAlignment.CENTER);
161         Font titleFont = workbook.createFont();
162         titleFont.setFontName(SHEET_FONT_TYPE);
163         titleFont.setFontHeightInPoints((short) 16);
164         titleFont.setBold(true);
165         style.setFont(titleFont);
166         styleMap.put("title", style);
167 
168         style = workbook.createCellStyle();
169         style.setVerticalAlignment(VerticalAlignment.CENTER);
170         style.setBorderRight(BorderStyle.THIN);
171         style.setRightBorderColor(IndexedColors.GREY_50_PERCENT.getIndex());
172         style.setBorderLeft(BorderStyle.THIN);
173         style.setLeftBorderColor(IndexedColors.GREY_50_PERCENT.getIndex());
174         style.setBorderTop(BorderStyle.THIN);
175         style.setTopBorderColor(IndexedColors.GREY_50_PERCENT.getIndex());
176         style.setBorderBottom(BorderStyle.THIN);
177         style.setBottomBorderColor(IndexedColors.GREY_50_PERCENT.getIndex());
178         Font dataFont = workbook.createFont();
179         dataFont.setFontName(SHEET_FONT_TYPE);
180         dataFont.setFontHeightInPoints((short) 10);
181         style.setFont(dataFont);
182         styleMap.put("data", style);
183 
184         style = workbook.createCellStyle();
185         style.cloneStyleFrom(styleMap.get("data"));
186         style.setWrapText(true);
187         style.setAlignment(HorizontalAlignment.CENTER);
188         style.setFillForegroundColor(IndexedColors.GREY_25_PERCENT.getIndex());
189         style.setFillPattern(FillPatternType.SOLID_FOREGROUND);
190         Font headerFont = workbook.createFont();
191         headerFont.setFontName(SHEET_FONT_TYPE);
192         headerFont.setFontHeightInPoints((short) 10);
193         headerFont.setBold(true);
194         headerFont.setColor(IndexedColors.WHITE.getIndex());
195         style.setFont(headerFont);
196         style.setBorderRight(BorderStyle.THIN);
197         styleMap.put("header", style);
198 
199         return styleMap;
200     }
201 
202     public Workbook getWorkbook() {
203         return workbook;
204     }
205 
206     public void setWorkbook(Workbook workbook) {
207         this.workbook = workbook;
208     }
209 
210     public Sheet getSheet() {
211         return sheet;
212     }
213 
214     public void setSheet(Sheet sheet) {
215         this.sheet = sheet;
216     }
217 
218     public int getRowNum() {
219         return rowNum;
220     }
221 
222     public void setRowNum(int rowNum) {
223         this.rowNum = rowNum;
224     }
225 
226     public Map getStyles() {
227         return styles;
228     }
229 
230     public void setStyles(Map styles) {
231         this.styles = styles;
232     }
233 
234     public List getColumns() {
235         return columns;
236     }
237 
238     public void setColumns(List columns) {
239         this.columns = columns;
240     }
241 
242     @Override
243     public void close() throws IOException {
244         if (workbook instanceof SXSSFWorkbook && ((SXSSFWorkbook) workbook).dispose())
245             workbook.close();
246     }
247 
248     class ColumnField {
249         private String title;
250         private String param;
251         private Class paramType;
252         private int width;
253 
254         ColumnField(String title, String param, Class paramType, int width) {
255             this.title = title;
256             this.param = param;
257             this.paramType = paramType;
258             this.width = width;
259         }
260 
261         public String getTitle() {
262             return title;
263         }
264 
265         public void setTitle(String title) {
266             this.title = title;
267         }
268 
269         public String getParam() {
270             return param;
271         }
272 
273         public void setParam(String param) {
274             this.param = param;
275         }
276 
277         public Class getParamType() {
278             return paramType;
279         }
280 
281         public void setParamType(Class paramType) {
282             this.paramType = paramType;
283         }
284 
285         public int getWidth() {
286             return width;
287         }
288 
289         public void setWidth(int width) {
290             this.width = width;
291         }
292     }
293 }

以下是两个注解

 1 @Target({ElementType.METHOD, ElementType.FIELD, ElementType.TYPE})
 2 @Retention(RetentionPolicy.RUNTIME)
 3 public @interface ExcelField {
 4 
 5     /**
 6      * 导出字段标题
 7      */
 8     String title();
 9 
10     /**
11      * 列宽
12      */
13     int width() default 10; // 后面还可以添加其他的属性，添加后再修改上面那个代码就行了
14 }

以上。

 

使用方式为：

 1 import com.xxx.utils.ExcelField;
 2 
 3 public class ExcelDataModel {
 4 
 5     @ExcelField(title = "ID", width = 4)
 6     private String id;
 7 
 8     @ExcelField(title = "序号", width = 4)
 9     private Integer serial;
10 
11     @ExcelField(title = "名字", width = 8)
12     private String name;
13     ... (getter\setter)

    @GetMapping(value = "export/post")
    public void exportPost(@ModelAttribute RequestModel model, HttpServletResponse response) {
        try (
                ExcelExport excelExport = new ExcelExport();
                OutputStream out = response.getOutputStream()
        ) {
            List data = xxxService.selectExportData(model);
            response.setContentType("octets/stream");
            response.addHeader("Content-Disposition", "attachment;filename=" + URLEncoder.encode("xx列表", "UTF-8")
                    + DateUtils.formatDate(new Date(), "yyyyMMddHHmmss") + ExcelExport.EXCEL_SUFFIX);
            String title = "xx列表";
            excelExport.createSheet("xx列表", title, ExcelDataModel.class);
            excelExport.setDataList(data);
            excelExport.write(out);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

over.

转载于:https://www.cnblogs.com/SummerinShire/p/11045254.html