如何从中比较列表的对象并删除重复项

时间:2019-12-06 11:21:55

标签: java excel list duplicates apache-poi

我有一个列表,其中有一些对象是从Excel文件中检索的。 这些对象是文件的行,由行定义: F_Name (名字), L_Name (姓氏), data_nascita (即出生日期)和 data_sinistro (即车祸发生日期)。

Excel文件用于模拟从数据库(具有更多字段)中提取查询,该数据库从前三个字段中唯一识别人员: F_Name L_Name data_nascita

文件中有8行; 前四行具有与后四行中的前三个字段相同的前三个字段; 该列表由这8行填充。

我的需要是: 如果在Excel文件中有一行,其前三个字段与另一行相同,则该列表必须仅包含具有最后一个日期的第四个字段( data_sinistro )的行。

这里有我的类(1 =应用所描述逻辑的ReadExcelDemo),(2 =数据,包含Excel文件四个字段的setter和getter)。

我试图对字段列表进行排序或比较,但没有成功...

请帮助我,谢谢大家!

(1)

package com.testing;

import java.io.File;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Comparator;
import java.util.Iterator;

import org.apache.poi.EncryptedDocumentException;
import org.apache.poi.openxml4j.exceptions.InvalidFormatException;
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.usermodel.WorkbookFactory;

public class ReadExcelDemo {

    public static void main(String[] args) throws EncryptedDocumentException, InvalidFormatException, IOException {
        String path = "C:\\Users\\CorsoUser08\\Documents\\DXC Technology\\tabellaAssicuratoEstrazioneJsonSigim.xlsx";
        ReadExcelDemo(path);
    }

    public static void ReadExcelDemo(String path) throws EncryptedDocumentException, InvalidFormatException, IOException {
           File file = new File(path);

           Workbook workbook = WorkbookFactory.create(file);
           Sheet sheet = workbook.getSheetAt(0);

           Iterator<Row> rowIterator = sheet.rowIterator();

           checkRows(rowIterator);
       }

    private static void checkRows(Iterator<Row> rowIterator) {
        // TODO Auto-generated method stub
        ArrayList<Datas> list = new ArrayList<Datas>();

        Datas obj = new Datas();

        while (rowIterator.hasNext()) {
            Row row = rowIterator.next();

            for (int i = 0; i < 4; i++) {
                obj.setF_Name(row.getCell(0).toString());
                obj.setL_Name(row.getCell(1).toString());
                obj.setData_nascita(row.getCell(2).toString());
                obj.setData_sinistro(row.getCell(3).toString());
            }
            list.add(obj); 
            System.out.println(obj.toString());
       }

//Start of comment//
            /*
            list.sort(new Comparator<Datas>() {

                public int compare(Datas o1, Datas o2) {
                    // TODO Auto-generated method stub
                    if (o1.getData_sinistro().compareTo(o2.getData_sinistro()) >= 0) {

                        return 0;
                    }
                    return 0;
                }       
            });

        Iterator<Datas> datasList = list.iterator();
        while (datasList.hasNext()) {
            Datas dat = datasList.next();
            System.out.println(dat.getF_Name());
            System.out.println(dat.getL_Name());
            System.out.println(dat.getData_nascita());
            System.out.println(dat.getData_sinistro());
        }
        */  
//End of comment//

    } 

}

(2)

package com.testing;

import java.util.Date;

public class Datas {

        String data_sinistro;
        String F_Name;
        String L_Name;

        String data_nascita;
        public String getData_nascita() {
            return data_nascita;
        }
        public void setData_nascita(String data_nascita) {
            this.data_nascita = data_nascita;
        }
        public String getData_sinistro() {
            return data_sinistro;
        }
        public void setData_sinistro(String data_sinistro) {
            this.data_sinistro = data_sinistro;
        }
        public String getF_Name() {
            return F_Name;
        }
        public void setF_Name(String f_Name) {
            F_Name = f_Name;
        }
        public String getL_Name() {
            return L_Name;
        }
        public void setL_Name(String l_Name) {
            L_Name = l_Name;
        }
}

1 个答案:

答案 0 :(得分:1)

如果您使用的是Java 8或更高版本,请尝试此操作。我认为它将解决。

private static ArrayList<Datas> checkRows(Iterator<Row> rowIterator) {
        // TODO Auto-generated method stub
        ArrayList<Datas> list = new ArrayList<Datas>();


        while (rowIterator.hasNext()) {
            Row row = rowIterator.next();

            Datas obj = new Datas();
            obj.setF_Name(row.getCell(0).toString());
            obj.setL_Name(row.getCell(1).toString());
            obj.setData_nascita(row.getCell(2).toString());
            obj.setData_sinistro(row.getCell(3).toString());

            Optional<Datas> opt = list.stream().filter(data -> {
                return data.getF_Name().equals(obj.getF_Name()) && data.getL_Name().equals(obj.getL_Name())
                        && data.getData_nascita().equals(obj.getData_nascita());
            }).findFirst();

            if (opt.isPresent()) {
                Datas inList = opt.get();
                if (inList.getData_sinistro().compareTo(obj.data_sinistro) < 0) {
                    inList.setData_sinistro(obj.data_sinistro);
                }
            } else {
                list.add(obj);
            }

       }

       return list;

    }