Question

是否有任何方法可以返回表格中存在的表格列表？我的要求是从工作表上的多个表中获取数据。

Answer 1

我们假设您正在使用XSSF API用于.xlsx excel文件。如果表格是由Insert->Table创建的，那么您可以使用以下内容来阅读它们：

XSSFWorkbook workbook = new XSSFWorkbook(new File("test.xlsx"));
int numberOfSheets = workbook.getNumberOfSheets();
for(int sheetIdx = 0; sheetIdx < numberOfSheets; sheetIdx++) {
    XSSFSheet sheet = workbook.getSheetAt(sheetIdx);
    List<XSSFTable> tables = sheet.getTables();
    for(XSSFTable t : tables) {
        System.out.println(t.getDisplayName());
        System.out.println(t.getName());
        System.out.println(t.getNumerOfMappedColumns());
    }
}

如果table表示任何有边框的东西，那么你必须创建一个非平凡的算法来读取每个工作表的所有单元格并检查边界（例如leftBorderColor，{{1 }}，rightBorderColor，topBorderColor）以及定义bottomBorderColor检查的内容，如果您已找到它。

Answer 2

对于所有想要从java代码中读取表的人，这是工作代码。

XSSFWorkbook workbook = new XSSFWorkbook(new File("test.xlsx"));
    int numberOfSheets = workbook.getNumberOfSheets();
    for (int sheetIdx = 0; sheetIdx < numberOfSheets; sheetIdx++) {
        XSSFSheet sheet = workbook.getSheetAt(sheetIdx);
        List<XSSFTable> tables = sheet.getTables();
        for (XSSFTable t : tables) {
            System.out.println(t.getDisplayName());
            System.out.println(t.getName());
            System.out.println(t.getNumerOfMappedColumns());

            int startRow = t.getStartCellReference().getRow();
            int endRow = t.getEndCellReference().getRow();
            System.out.println("startRow = " + startRow);
            System.out.println("endRow = " + endRow);

            int startColumn = t.getStartCellReference().getCol();
            int endColumn = t.getEndCellReference().getCol();

            System.out.println("startColumn = " + startColumn);
            System.out.println("endColumn = " + endColumn);

            for (int i = startRow; i <= endRow; i++) {
                String cellVal = "";

                for (int j = startColumn; j <= endColumn; j++) {
                    XSSFCell cell = sheet.getRow(i).getCell(j);
                    if (cell != null) {
                        cellVal = cell.getStringCellValue();
                    }
                    System.out.print(cellVal + "\t");
                }
                System.out.println();
            }

        }
    }

    workbook.close();

Answer 3

我写这篇文章是为了将它与Pojo类和注释一起使用：

import java.io.File;
import java.lang.reflect.Field;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import org.apache.commons.lang3.reflect.FieldUtils;
import org.apache.commons.lang3.tuple.ImmutablePair;
import org.apache.commons.lang3.tuple.Pair;
import org.apache.poi.xssf.usermodel.XSSFCell;
import org.apache.poi.xssf.usermodel.XSSFSheet;
import org.apache.poi.xssf.usermodel.XSSFTable;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;

import com.madx.finance.data.utils.exels.read.ExelColumn;

public class Main {

    public static void main(String[] args) throws Exception {
        readExel(ExamplePojo.class);
    }

    public static class ExamplePojo  {
        public ExamplePojo(){}
        @ExelColumn(columnName="Column 1 String Name On Exel")
        protected String column1;
        @ExelColumn(columnName="Column 2 String Name On Exel")
        protected String column2;
    }

    public static <T> List<T> readExel(Class<T> clazz) throws Exception {
        List<T> rows = new ArrayList<T>();
        XSSFWorkbook workbook = new XSSFWorkbook(new File("test.xlsx"));

        int numberOfSheets = workbook.getNumberOfSheets();
        for (int sheetIdx = 0; sheetIdx < numberOfSheets; sheetIdx++) {
            XSSFSheet sheet = workbook.getSheetAt(sheetIdx);
            List<XSSFTable> tables = sheet.getTables();
            for (XSSFTable t : tables) {
                System.out.println(t.getDisplayName());
                System.out.println(t.getName());
                System.out.println(t.getNumerOfMappedColumns());

                int startRow = t.getStartCellReference().getRow();
                int endRow = t.getEndCellReference().getRow();
                System.out.println("startRow = " + startRow);
                System.out.println("endRow = " + endRow);

                int startColumn = t.getStartCellReference().getCol();
                int endColumn = t.getEndCellReference().getCol();

                System.out.println("startColumn = " + startColumn);
                System.out.println("endColumn = " + endColumn);

                // Loads all the annotated fields and builds a map for:
                // columnName, field
                List<Field> annotatedFields = FieldUtils.getFieldsListWithAnnotation(clazz, ExelColumn.class);
                Map<String, Field> annotatedFieldsMap = new HashMap<String, Field>();
                for (Field field : annotatedFields)
                    annotatedFieldsMap.put(field.getAnnotation(ExelColumn.class).columnName(), field);

                // Reads the used header names
                List<Pair<Integer, Field>> consideredColumns = new ArrayList<Pair<Integer, Field>>();
                for (int j = startColumn; j <= endColumn; j++) {
                    XSSFCell cell = sheet.getRow(startRow).getCell(j);
                    if (cell != null) {
                        String columnName = cell.getStringCellValue();
                        Field field = annotatedFieldsMap.get(columnName);
                        if (field != null) {
                            Integer cellColumn = j;
                            Pair<Integer, Field> p = new ImmutablePair<Integer, Field>(cellColumn, field);
                            consideredColumns.add(p);
                        }
                    }
                }

                for (int i = startRow + 1; i <= endRow; i++) {
                    try {
                        T row = clazz.newInstance();
                        for (Pair<Integer, Field> pair : consideredColumns) {
                            XSSFCell cell = sheet.getRow(i).getCell(pair.getKey());
                            if (cell != null) {
                                Field field = pair.getValue();
                                field.setAccessible(true);
                                Class<?> fieldClass = field.getType();
                                if(Number.class.isAssignableFrom(fieldClass)){
                                    field.set(row, cell.getNumericCellValue());
                                } else {
                                    field.set(row, cell.getStringCellValue());
                                }
                            }
                        }
                        rows.add(row);
                    } catch (InstantiationException | IllegalAccessException e) {
                        e.printStackTrace();
                    }
                }
            }
        }

        workbook.close();
        return rows;
    }
}

Apache POI：用于识别Excel工作表中的表并读取它们的API

3 个答案: