import java.io.Serializable;/** * POI Excel报表导出，列合并实体 * * @author WQ * */public class PoiModel implements Serializable{ /** * */ private static final long serialVersionUID = 1L; private String content; private String oldContent; private int rowIndex; private int cellIndex; public String getContent() { return content; } public void setContent(String content) { this.content = content; } public String getOldContent() { return oldContent; } public void setOldContent(String oldContent) { this.oldContent = oldContent; } public int getRowIndex() { return rowIndex; } public void setRowIndex(int rowIndex) { this.rowIndex = rowIndex; } public int getCellIndex() { return cellIndex; } public void setCellIndex(int cellIndex) { this.cellIndex = cellIndex; } public PoiModel() { } public PoiModel(String content, String oldContent, int rowIndex, int cellIndex) { this.content = content; this.oldContent = oldContent; this.rowIndex = rowIndex; this.cellIndex = cellIndex; } @Override public String toString() { return "PoiModel [content=" + content + ", oldContent=" + oldContent + ", rowIndex=" + rowIndex + ", cellIndex=" + cellIndex + "]"; } }
import java.io.File;import java.io.FileOutputStream;import java.io.IOException;import java.util.ArrayList;import java.util.Date;import java.util.HashMap;import java.util.Iterator;import java.util.List;import java.util.Map;import org.apache.poi.ss.usermodel.Cell;import org.apache.poi.ss.usermodel.Row;import org.apache.poi.ss.usermodel.Sheet;import org.apache.poi.ss.usermodel.Workbook;import org.apache.poi.ss.util.CellRangeAddress;import org.apache.poi.xssf.usermodel.XSSFWorkbook;public class Demo { /** * @param title 标题集合 tilte的长度应该与list中的model的属性个数一致 * @param maps 内容集合 * @param mergeIndex 合并单元格的列 */ public static String createExcel(String[] title, Map >> maps, int[] mergeIndex){ if (title.length==0){ return null; } /*初始化excel模板*/ Workbook workbook = new XSSFWorkbook(); Sheet sheet = null; int n = 0; for(Map.Entry >> entry : maps.entrySet()){ try { sheet = workbook.createSheet(); workbook.setSheetName(n, entry.getKey()); workbook.setSelectedTab(0); }catch (Exception e){ e.printStackTrace(); } /*初始化head，填值标题行（第一行）*/ Row row0 = sheet.createRow(0); for(int i = 0; i > list = entry.getValue(); /*遍历该数据集合*/ List poiModels = new ArrayList(); if(null!=workbook){ Iterator iterator = list.iterator(); int index = 1; while (iterator.hasNext()){ Row row = sheet.createRow(index); /*取得当前这行的map，该map中以key，value的形式存着这一行值*/ Map map = (Map )iterator.next(); /*循环列数，给当前行塞值*/ for(int i = 0; i 1){ old = poiModels.get(i)==null?"":poiModels.get(i).getContent(); } /*循环需要合并的列*/ for(int j = 0; j < mergeIndex.length; j++){ if(index == 1){ /*记录第一行的开始行和开始列*/ PoiModel poiModel = new PoiModel(); poiModel.setOldContent(map.get(title[i])); poiModel.setContent(map.get(title[i])); poiModel.setRowIndex(1); poiModel.setCellIndex(i); poiModels.add(poiModel); break; }else if(i > 0 && mergeIndex[j] == i){ /*这边i>0也是因为第一列已经是最前一列了，只能从第二列开始*/ /*当前同一列的内容与上一行同一列不同时，把那以上的合并, 或者在当前元素一样的情况下，前一列的元素并不一样，这种情况也合并*/ /*如果不需要考虑当前行与上一行内容相同，但是它们的前一列内容不一样则不合并的情况，把下面条件中 ||poiModels.get(i).getContent().equals(map.get(title[i])) && !poiModels.get(i - 1).getOldContent().equals(map.get(title[i-1]))去掉就行*/ if(!poiModels.get(i).getContent().equals(map.get(title[i])) || poiModels.get(i).getContent().equals(map.get(title[i])) && !poiModels.get(i - 1).getOldContent().equals(map.get(title[i-1]))){ /*当前行的当前列与上一行的当前列的内容不一致时，则把当前行以上的合并*/ CellRangeAddress cra=new CellRangeAddress(poiModels.get(i).getRowIndex(), index - 1, poiModels.get(i).getCellIndex(), poiModels.get(i).getCellIndex()); //在sheet里增加合并单元格 sheet.addMergedRegion(cra); /*重新记录该列的内容为当前内容，行标记改为当前行标记，列标记则为当前列*/ poiModels.get(i).setContent(map.get(title[i])); poiModels.get(i).setRowIndex(index); poiModels.get(i).setCellIndex(i); } } /*处理第一列的情况*/ if(mergeIndex[j] == i && i == 0 && !poiModels.get(i).getContent().equals(map.get(title[i]))){ /*当前行的当前列与上一行的当前列的内容不一致时，则把当前行以上的合并*/ CellRangeAddress cra=new CellRangeAddress(poiModels.get(i).getRowIndex(), index - 1, poiModels.get(i).getCellIndex(), poiModels.get(i).getCellIndex()); //在sheet里增加合并单元格 sheet.addMergedRegion(cra); /*重新记录该列的内容为当前内容，行标记改为当前行标记*/ poiModels.get(i).setContent(map.get(title[i])); poiModels.get(i).setRowIndex(index); poiModels.get(i).setCellIndex(i); } /*最后一行没有后续的行与之比较，所有当到最后一行时则直接合并对应列的相同内容*/ if(mergeIndex[j] == i && index == list.size()){ CellRangeAddress cra=new CellRangeAddress(poiModels.get(i).getRowIndex(), index, poiModels.get(i).getCellIndex(), poiModels.get(i).getCellIndex()); //在sheet里增加合并单元格 sheet.addMergedRegion(cra); } } Cell cell = row.createCell(i, Cell.CELL_TYPE_STRING); cell.setCellValue(map.get(title[i])); /*在每一个单元格处理完成后，把这个单元格内容设置为old内容*/ poiModels.get(i).setOldContent(old); } index++; } } n++; } /*生成临时文件*/ FileOutputStream out = null; String localPath = null; File tempFile = null; String fileName = String.valueOf(new Date().getTime()/1000); try { tempFile = File.createTempFile(fileName, ".xlsx"); localPath = tempFile.getAbsolutePath(); out = new FileOutputStream(localPath); workbook.write(out); }catch (IOException e){ e.printStackTrace(); }finally { try { out.flush(); out.close(); }catch (IOException e){ e.printStackTrace(); } } return localPath; } public static void main(String[] args) throws IOException{ /*此处标题的数组则对应excel的标题*/ String[] title = {"id","标题","描述","负责人","开始时间"}; List
思路：
后来就通过建一个单元格对象，属性有单元格内容，与单元格同一列的上一行内容，起始行，起始列，就这四个属性
生成的文件效果（两种情况的）：
