如何從JAVA中的Excel文件解析樹結構

Question

大家好！ 我需要從Excel解析樹結構，例如：ABCDEFGKMO等，而文件沒有結束

我有一個實體類科：

@Getter
@Setter
public class Section {
  private int depth;
  private String text;
  private int parentLevel;
  private List<Section> children;

  public Section(String text, int depth) {
    this.text = text;
    this.depth = depth;
    this.children = new ArrayList<Section>();
    this.parentLevel = 0;
  }

  public Section(String text, int depth, int parent) {
    this.text = text;
    this.depth = depth;
    this.children = new ArrayList<Section>();
    this.parentLevel = parent;
  }

  public boolean addChild(Section section) {
    return children.add(section);
  }

  @Override
  public String toString() {
    return "Section{" + "depth=" + depth + ", text='" + text + '\''
        + ", children=" + children + '}';
  }
}

和從excel讀取數據並嘗試解析的方法，但是我不知道如何以最佳方式解析它。 我無法將孩子名單與他們的父母聯系起來。

和方法：

public void read() throws ResourceNotFoundException {
    try {

      XSSFWorkbook excelBook = new XSSFWorkbook(new FileInputStream(ExcelConstant.FILE_NAME));
      XSSFSheet excelSheet = excelBook.getSheet(ExcelConstant.SHEET_NAME);

      Section prev = null;

      int prevKey = 0;

      for (Row row : excelSheet) {
        for (Cell cell : row) {
          if (cell.getCellType() == Cell.CELL_TYPE_STRING) {
            int current = cell.getColumnIndex();
            if (prev == null && current == 0) {
              prev = new Section(cell.getStringCellValue(), current);
            } else if (prev != null) {
              if (current > prevKey) {
                Section section = new Section(cell.getStringCellValue(), current, prevKey);
                prev.addChild(section);
                prevKey = current;
              }
              if (current == prevKey) {
                Section section = new Section(cell.getStringCellValue(), current, prev.getParentLevel());
                prev.addChild(section);
              } else {
                while (current < prev.getDepth()) {
                  prevKey = prev.getParentLevel();
                }
                Section t_section = new Section(cell.getStringCellValue(), current, prevKey);
                prev.addChild(t_section);
              }
            }


          }
        }
      }


      System.out.println(prev);

    } catch (IOException e) {
      throw new ResourceNotFoundException("Read data from excel file exception", e);
    }
  }

Answer 1

解決以下問題：

• 樹狀結構
• 員工經理
• 目錄結構
• 等等

GoF提供復合模式

這是一個示例Java程序：

Composite.java

package com.test;

import java.util.ArrayList;
import java.util.List;

public class Composite {

    private String text;
    private List<Composite> children = new ArrayList<>();

    public Composite(String text) {
        this.text = text;
    }

    public String getText() {
        return text;
    }

    public void setText(String text) {
        this.text = text;
    }

    public void add(Composite child) {
        children.add(child);
    }

    public void remove(Composite child) {
        children.remove(child);
    }

    public List<Composite> getChildren() {
        return children;
    }

    @Override
    public String toString() {
        return "Composite [text=" + text + ", children=" + children + "]";
    }

}

ExcelParser.java

package com.test;

import java.io.FileInputStream;
import java.util.LinkedHashMap;
import java.util.Map;

import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.xssf.usermodel.XSSFSheet;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;

public class ExcelParser {
    private Map<String, Composite> compositeMap = new LinkedHashMap<>();

    public Composite parse() throws Exception {
        Composite root = new Composite("Root");
        String[][] array = getArrayFromExcel();
        for (int i = 0; i < array.length; i++) {
            String[] row = array[i];
            for (int j = row.length - 1; j > -1; j--) {
                Composite current = compositeMap.get("" + i + j);
                Composite parent = compositeMap.get("" + i + (j - 1));
                if (current != null) {
                    if (j - 1 < 0) {
                        parent = root;
                    } else if (parent == null) {
                        for (int k = i - 1; k > -1; k--) {
                            parent = compositeMap.get("" + k + (j - 1));
                            if (parent != null) {
                                break;
                            }
                        }
                    }
                    if (parent == null) {
                        throw new Exception("Invalid Input");
                    } else {
                        parent.getChildren().add(current);
                    }
                }
            }
        }
        return root;
    }

    public String[][] getArrayFromExcel() throws Exception {
        XSSFWorkbook excelBook = new XSSFWorkbook(new FileInputStream("Book1.xlsx"));
        XSSFSheet excelSheet = excelBook.getSheet("Sheet1");
        int rowNums = excelSheet.getPhysicalNumberOfRows();
        int colNums = 0;
        for (Row row : excelSheet) {
            if (colNums < row.getLastCellNum()) {
                colNums = row.getLastCellNum();
            }
        }
        String[][] array = new String[rowNums][colNums];
        int i = 0;
        for (Row row : excelSheet) {
            int j = 0;
            for (Cell column : row) {
                j = column.getColumnIndex();
                String text = column.getStringCellValue();
                array[i][j] = text;
                compositeMap.put("" + i + j, new Composite(text));
                j++;
            }
            i++;
        }
        print(array);
        return array;
    }

    private void print(String[][] array) {
        for (String[] row : array) {
            for (String data : row) {
                System.out.print(data + "\t");
            }
            System.out.println();
        }
    }
}

Main.java

com.test;

public class Main {

    public static void main(String[] args) throws Exception {
        ExcelParser parser = new ExcelParser();
        Composite root = parser.parse();
        System.out.println(root);
    }

}

輸出：

A   A_1 null    null    
null    A_2 null    null    
B   B_1 null    null    
C   null    null    null    
D   D_1 D_1_1   null    
null    null    D_1_2   D_1_2_1 
null    null    null    D_1_2_2 
null    null    null    D_1_2_3 
null    D_2 null    null    
null    D_3 null    null    
null    D_4 null    null    
E   null    null    null    
Composite [text=Root, children=[Composite [text=A, children=[Composite [text=A_1, children=[]], Composite [text=A_2, children=[]]]], Composite [text=B, children=[Composite [text=B_1, children=[]]]], Composite [text=C, children=[]], Composite [text=D, children=[Composite [text=D_1, children=[Composite [text=D_1_1, children=[]], Composite [text=D_1_2, children=[Composite [text=D_1_2_1, children=[]], Composite [text=D_1_2_2, children=[]], Composite [text=D_1_2_3, children=[]]]]]], Composite [text=D_2, children=[]], Composite [text=D_3, children=[]], Composite [text=D_4, children=[]]]], Composite [text=E, children=[]]]]