public boolean isCellEditable(int row,int column){ if(column==0){ return false; }else { return true; } }//设置表格模型第一列不能修改 public void settValueAt(Object aValue,int row,int column){ super.setValueAt(aValue,row,column); int i,count=editedIndex.size(); if (count==0){ editedIndex.add(row); }else { for (i=0;i<count;i++){ if (editedIndex.get(i).intValue()>row){ editedIndex.add(i+1,row); break; } if (i>=count){ editedIndex.add(row); } } } }//表格模型数据修改后，记录器行号 public ArrayList <Integer> getEditedIndex(){ return editedIndex; }//自定义方法，获取表格模型修改的数据行号列表

这段代码实现了一个自定义的TableModel类(MyTableModel)，这个类继承了JTable的默认TableModel，并添加了一些自定义的功能。其中，isCellEditable方法用于控制表格模型的第一列是否可以修改，如果列号为0，则返回false，否则返回true。settValueAt方法用于在表格模型数据被修改后记录被修改的行号。具体来说，当数据被修改时，它会调用父类的setValueAt方法，然后将被修改的行号记录到一个ArrayList对象(editedIndex)中。这个ArrayList对象在getEditedIndex方法中被返回，用于获取表格模型修改的数据行号列表。这个TableModel类可以用来在GUI界面中显示数据，并记录数据的修改情况，方便后续的保存操作。

相关问题

在下列方法上新增功能，第四列，第五列，第六列的合并行数以第三列的合并行数为准 public static int exportToExcelForXlsx(List<List> objData, String sheetName, List<String> columns, List mergeIndex, HttpServletResponse response) { int flag = 0; XSSFWorkbook wb = new XSSFWorkbook(); XSSFSheet sheet1 = wb.createSheet(sheetName); sheet1row1.setHeight((short) 520); if (columns != null && columns.size() > 0) { for(int i=0;i<columns.size();i++) { String column = columns.get(i); //列 XSSFCell cell = sheet1row1.createCell(i); cell.setCellValue(column); } } int dataSatrtIndex = 1; boolean isMerge = false; if(mergeIndex != null && mergeIndex.size() != 0) { isMerge = true; } if (objData != null && objData.size() > 0) { Map<Integer, PoiModel> poiModels = new HashMap<Integer, PoiModel>(); int i = 0; for ( ; i < objData.size(); i++) { XSSFRow row = sheet1.createRow((short) (i+dataSatrtIndex)); List<Object> list = objData.get(i); DecimalFormat decimalFormat = new DecimalFormat("0.00"); int j = 0; for (Object o : list) { String content = ""; if(o != null) { if (o.toString().contains(".") && isNumeric(o.to }else { XSSFCell cell = row.createCell(j); cell.setCellValue(content); } j++; } } if(poiModels != null && poiModels.size() != 0) { for(Integer key : poiModels.keySet()) { PoiModel poiModel = poiModels.get(key); XSSFRow lastRow = sheet1.getRow(poiModel.getRowIndex()); XSSFCell lastCell = lastRow.getCell(poiModel.getCellIndex()); lastCell.setCellValue(poiModel.getContent()); lastCell.setCellStyle(style); lastRow.setRowStyle(style); if(poiModel.getRowIndex() != i + dataSatrtIndex -1) { sheet1.addMergedRegion(new CellRangeAddress(poiModel.getRowIndex(), i + dataSatrtIndex - 1, poiModel.getCellIndex(), poiModel.getCellIndex())); } } } } else { flag = -1; }

可以考虑新增以下功能：

1. 合并单元格：根据传入的合并行数，将指定列的单元格进行合并。可以使用XSSFCellStyle的setAlignment()方法，将内容对齐方式设置为居中。

示例代码：

// 获取合并列数
int mergeCount = Integer.parseInt(mergeIndex.get(2).toString());

// 合并单元格
for (int i = 0; i < mergeCount; i++) {
    String startCell = mergeIndex.get(0) + (Integer.parseInt(mergeIndex.get(1).toString()) + i);
    String endCell = mergeIndex.get(0) + (Integer.parseInt(mergeIndex.get(1).toString()) + mergeCount - 1);
    CellRangeAddress cellRange = new CellRangeAddress(CellReference.convertColStringToIndex(startCell.substring(0, 1)), Integer.parseInt(startCell.substring(1)) - 1,
                                                      CellReference.convertColStringToIndex(endCell.substring(0, 1)), Integer.parseInt(endCell.substring(1)) - 1);
    sheet1.addMergedRegion(cellRange);
    // 设置对齐方式
    XSSFCellStyle style = wb.createCellStyle();
    style.setAlignment(HorizontalAlignment.CENTER);
    cellRange.setCellStyle(style);
}

2. 设置表头样式：可以使用XSSFCellStyle的setFont()方法和setFillForegroundColor()方法，分别设置字体和背景颜色。

示例代码：

// 设置表头样式
XSSFCellStyle headerStyle = wb.createCellStyle();
headerStyle.setFillForegroundColor(IndexedColors.GREY_25_PERCENT.getIndex());
headerStyle.setFillPattern(FillPatternType.SOLID_FOREGROUND);
XSSFFont font = wb.createFont();
font.setFontHeightInPoints((short) 12);
font.setBold(true);
headerStyle.setFont(font);
// 设置表头单元格样式
for (int i = 0; i < columns.size(); i++) {
    sheet1row1.getCell(i).setCellStyle(headerStyle);
}

3. 设置列宽：可以使用setColumnWidth()方法设置指定列的宽度。

示例代码：

// 设置列宽
for (int i = 0; i < columns.size(); i++) {
    sheet1.setColumnWidth(i, 5000);
}

完整代码如下：

public static int exportToExcelForXlsx(List<List> objData, String sheetName, List<String> columns, List mergeIndex, HttpServletResponse response) {
    int flag = 0;
    XSSFWorkbook wb = new XSSFWorkbook();
    XSSFSheet sheet1 = wb.createSheet(sheetName);
    // 创建表头
    XSSFRow sheet1row1 = sheet1.createRow(0);
    for (int i = 0; i < columns.size(); i++) {
        sheet1row1.createCell(i).setCellValue(columns.get(i));
    }
    // 设置表头样式
    XSSFCellStyle headerStyle = wb.createCellStyle();
    headerStyle.setFillForegroundColor(IndexedColors.GREY_25_PERCENT.getIndex());
    headerStyle.setFillPattern(FillPatternType.SOLID_FOREGROUND);
    XSSFFont font = wb.createFont();
    font.setFontHeightInPoints((short) 12);
    font.setBold(true);
    headerStyle.setFont(font);
    // 设置表头单元格样式
    for (int i = 0; i < columns.size(); i++) {
        sheet1row1.getCell(i).setCellStyle(headerStyle);
    }
    // 填充数据
    for (int i = 0; i < objData.size(); i++) {
        XSSFRow row = sheet1.createRow(i + 1);
        for (int j = 0; j < objData.get(i).size(); j++) {
            row.createCell(j).setCellValue(objData.get(i).get(j).toString());
        }
    }
    // 设置列宽
    for (int i = 0; i < columns.size(); i++) {
        sheet1.setColumnWidth(i, 5000);
    }
    // 合并单元格
    int mergeCount = Integer.parseInt(mergeIndex.get(2).toString());
    for (int i = 0; i < mergeCount; i++) {
        String startCell = mergeIndex.get(0) + (Integer.parseInt(mergeIndex.get(1).toString()) + i);
        String endCell = mergeIndex.get(0) + (Integer.parseInt(mergeIndex.get(1).toString()) + mergeCount - 1);
        CellRangeAddress cellRange = new CellRangeAddress(CellReference.convertColStringToIndex(startCell.substring(0, 1)), Integer.parseInt(startCell.substring(1)) - 1,
                                                          CellReference.convertColStringToIndex(endCell.substring(0, 1)), Integer.parseInt(endCell.substring(1)) - 1);
        sheet1.addMergedRegion(cellRange);
        // 设置对齐方式
        XSSFCellStyle style = wb.createCellStyle();
        style.setAlignment(HorizontalAlignment.CENTER);
        cellRange.setCellStyle(style);
    }
    // 导出excel文件
    try {
        OutputStream out = response.getOutputStream();
        String fileName = sheetName + ".xlsx";
        response.setHeader("Content-disposition", "attachment;filename=" + URLEncoder.encode(fileName, "UTF-8"));
        response.setContentType("application/vnd.ms-excel;charset=utf-8");
        wb.write(out);
        out.flush();
        out.close();
    } catch (IOException e) {
        e.printStackTrace();
        flag = 1;
    }
    return flag;
}

jtable 合并单元格 详细代码

以下是使用 JTable 实现单元格合并的详细代码：

首先，我们需要自定义一个 TableModel 类来实现单元格合并：

import javax.swing.table.AbstractTableModel;
import java.util.HashMap;
import java.util.Map;
 
public class MergeTableModel extends AbstractTableModel {
    private Object[][] data;
    private String[] columnNames;
    private Map<CellIndex, CellSpan> spanMap;
 
    public MergeTableModel(Object[][] data, String[] columnNames) {
        this.data = data;
        this.columnNames = columnNames;
        this.spanMap = new HashMap<>();
    }
 
    public void merge(int startRow, int endRow, int startCol, int endCol) {
        spanMap.put(new CellIndex(startRow, startCol), new CellSpan(endRow - startRow + 1, endCol - startCol + 1));
    }
 
    @Override
    public int getRowCount() {
        return data.length;
    }
 
    @Override
    public int getColumnCount() {
        return columnNames.length;
    }
 
    @Override
    public Object getValueAt(int rowIndex, int columnIndex) {
        CellSpan span = spanMap.get(new CellIndex(rowIndex, columnIndex));
        if (span != null) {
            return null;
        }
        return data[rowIndex][columnIndex];
    }
 
    @Override
    public boolean isCellEditable(int rowIndex, int columnIndex) {
        return false;
    }
 
    public int getRealRow(int row) {
        int realRow = row;
        for (CellIndex cellIndex : spanMap.keySet()) {
            CellSpan span = spanMap.get(cellIndex);
            int endRow = cellIndex.row + span.row - 1;
            if (row >= cellIndex.row && row <= endRow) {
                realRow = cellIndex.row;
                break;
            }
        }
        return realRow;
    }
 
    public int getRealColumn(int column) {
        int realColumn = column;
        for (CellIndex cellIndex : spanMap.keySet()) {
            CellSpan span = spanMap.get(cellIndex);
            int endColumn = cellIndex.column + span.column - 1;
            if (column >= cellIndex.column && column <= endColumn) {
                realColumn = cellIndex.column;
                break;
            }
        }
        return realColumn;
    }
 
    public int getRowSpan(int row, int column) {
        CellSpan span = spanMap.get(new CellIndex(row, column));
        if (span != null) {
            return span.row;
        }
        return 1;
    }
 
    public int getColumnSpan(int row, int column) {
        CellSpan span = spanMap.get(new CellIndex(row, column));
        if (span != null) {
            return span.column;
        }
        return 1;
    }
 
    private static class CellIndex {
        private int row;
        private int column;
 
        private CellIndex(int row, int column) {
            this.row = row;
            this.column = column;
        }
 
        @Override
        public boolean equals(Object o) {
            if (this == o) return true;
            if (o == null || getClass() != o.getClass()) return false;
            CellIndex cellIndex = (CellIndex) o;
            if (row != cellIndex.row) return false;
            return column == cellIndex.column;
        }
 
        @Override
        public int hashCode() {
            int result = row;
            result = 31 * result + column;
            return result;
        }
    }
 
    private static class CellSpan {
        private int row;
        private int column;
 
        private CellSpan(int row, int column) {
            this.row = row;
            this.column = column;
        }
    }
}

然后，我们在创建 JTable 的时候使用自定义的 TableModel 类，并在需要合并单元格的地方调用 merge 方法：

// 创建数据和列名
Object[][] data = {
    {"1", "A", "B", "C"},
    {"2", "D", "E", "F"},
    {"3", "G", "H", "I"},
    {"4", "J", "K", "L"}
};
String[] columnNames = {"#", "Column 1", "Column 2", "Column 3"};
 
// 创建自定义 TableModel
MergeTableModel tableModel = new MergeTableModel(data, columnNames);
 
// 创建 JTable
JTable table = new JTable(tableModel);
 
// 合并单元格
tableModel.merge(0, 1, 1, 2);
tableModel.merge(2, 3, 2, 3);
 
// 创建 JScrollPane 并将 JTable 添加到其中
JScrollPane scrollPane = new JScrollPane(table);

最后，我们需要重写 JTable 的 getCellRenderer 方法来实现单元格的合并显示：

// 创建 DefaultTableCellRenderer
DefaultTableCellRenderer renderer = new DefaultTableCellRenderer() {
    @Override
    public Component getTableCellRendererComponent(JTable table, Object value, boolean isSelected, boolean hasFocus, int row, int column) {
        Component c = super.getTableCellRendererComponent(table, value, isSelected, hasFocus, row, column);
        int realRow = tableModel.getRealRow(row);
        int realColumn = tableModel.getRealColumn(column);
        int rowSpan = tableModel.getRowSpan(realRow, realColumn);
        int colSpan = tableModel.getColumnSpan(realRow, realColumn);
        if (rowSpan > 1 || colSpan > 1) {
            Rectangle rect = table.getCellRect(realRow, realColumn, false);
            for (int i = realRow; i < realRow + rowSpan; i++) {
                for (int j = realColumn; j < realColumn + colSpan; j++) {
                    if (i == realRow && j == realColumn) {
                        continue;
                    }
                    rect.add(table.getCellRect(i, j, false));
                }
            }
            c.setBounds(rect);
            ((JComponent) c).setOpaque(false);
        } else {
            ((JComponent) c).setOpaque(true);
        }
        return c;
    }
};
 
// 设置渲染器
table.setDefaultRenderer(Object.class, renderer);