java poi分批次導入Excel

時間 2019-12-11

標籤 java poi 批次導入 excel 欄目 Java 简体版

原文原文鏈接

最近換了新工做，公司要求導入Excel要分批次導入，而且是多線程的狀況下執行導入，查了不少資料，沒看到比較複合的，就打算本身寫一個吧，可能有不足，但願指出。java

上面說到多線程，這邊就不貼出代碼了，具體思路就是一個導入開闢一個線程，下面主要寫一下個人分批次的代碼思路：c++

分批次導入-方法一

先介紹我一開始的寫法：apache

經過一個（最大行數/設置讀取的行數）的餘數向上取整來控制循環次數。多線程

 1 package oldboy;
 2 
 3 import org.apache.poi.hssf.usermodel.HSSFWorkbook;
 4 import org.apache.poi.ss.usermodel.Cell;
 5 import org.apache.poi.ss.usermodel.Row;
 6 import org.apache.poi.ss.usermodel.Sheet;
 7 
 8 import java.io.File;
 9 import java.io.FileInputStream;
10 
11 /**
12  * Created by peng on 18/9/12.
13  */
14 public class ExcelDemo {
15 
16     public static int READ_INDEX = 10;//這裏設置每次讀取的行數
17 
18     public static void main(String[] args) throws Exception {
19         testImport();
20     }
21 
22     public static void testImport() throws Exception {
23         boolean flag = true;
24         //cycleNum 循環讀取次數
25         int cycleNum = read("/Users/peng/Desktop/20180912/111.xls", 0);
26         while (flag) {
27             if (cycleNum != 0) {
28                 cycleNum = read("/Users/peng/Desktop/20180912/111.xls", cycleNum);
29             } else {
30                 flag = false;
31             }
32         }
33     }
34 
35     /**
36      * 讀取Excel
37      *
38      * @param localPath 文件路徑
39      * @param cycleNum  剩餘的讀取次數
40      * @return
41      * @throws Exception
42      */
43     public static int read(String localPath, int cycleNum) throws Exception {
44         File file = new File(localPath);
45         FileInputStream inputStream = new FileInputStream(file);
46         HSSFWorkbook book = new HSSFWorkbook(inputStream);
47         Sheet sheet = book.getSheetAt(0); //sheet 從0開始
48         Row row = sheet.getRow(0);      //獲取第一行
49         int rowEndNum = getRow();  //取得最後一行的行號
50         //向上取整
51         int cycleIndex = (int) (Math.ceil((double) rowEndNum / (double) READ_INDEX));
52         int cycleStartNum, cycleEndNum;
53         if (cycleNum == 0) {//第一次循環進來
54             cycleNum = cycleIndex;
55             cycleStartNum = 1;
56             if (rowEndNum > READ_INDEX) {
57                 cycleEndNum = READ_INDEX + 1;
58             } else {//第一次循環若是最大行數小於設定的讀取行數
59                 cycleEndNum = rowEndNum;
60             }
61         } else {
62             if (cycleNum == 1) {//最後一次循環的時候
63                 cycleStartNum = READ_INDEX * (cycleIndex - cycleNum) + 1;
64                 cycleEndNum = rowEndNum;
65             } else {
66                 cycleStartNum = READ_INDEX * (cycleIndex - cycleNum) + 1;
67                 cycleEndNum = READ_INDEX + READ_INDEX * (cycleIndex - cycleNum) + 1;
68             }
69         }
70         cycleNum -= 1;
71         //每次循環的開始行數和結束行數
72         System.out.println(cycleStartNum + "=======" + cycleEndNum);
73         //System.out.println(rowEndNum);
74         for (int i = cycleStartNum; i < cycleEndNum; i++) {//跳過第一行從第二行開始循環
75             row = sheet.getRow(i);
76             for (int j = 0; j < row.getLastCellNum(); j++) {//列循環開始,從第0列開始
77                 Cell cell = row.getCell(j);
78                 //ExcelUtils.getCellValue獲取單元格內容，這裏忽略
79                 String cellValue = ExcelUtils.getCellValue(cell);
80                 //System.out.print(cellValue.concat("   |  "));
81             }
82             //System.out.println();
83         }
84         //返回剩餘循環次數
85         return cycleNum;
86     }
87 
88     //這裏獲取Excel的真實行數
89     public static int getRow() {
90         return 47;
91     }
92 
93 }

執行結果：spa

分批次導入-方法二

這個方法是我比較推薦的，最後我也是採用這種寫法，一次讀一行，每次讀到設定的行數就保存一次，讀到空行中止。線程

 1 package oldboy;
 2 
 3 import org.apache.poi.hssf.usermodel.HSSFWorkbook;
 4 import org.apache.poi.ss.usermodel.Cell;
 5 import org.apache.poi.ss.usermodel.Row;
 6 import org.apache.poi.ss.usermodel.Sheet;
 7 
 8 import java.io.File;
 9 import java.io.FileInputStream;
10 import java.util.ArrayList;
11 import java.util.List;
12 
13 /**
14  * Created by peng on 18/9/12.
15  */
16 public class ExcelDemo1 {
17 
18     public static int READ_INDEX = 10;//這裏設置每次讀取的行數
19 
20     public static void main(String[] args) throws Exception {
21         testNewImport();
22     }
23 
24 
25     public static void testNewImport() throws Exception {
26         String localPath = "/Users/peng/Desktop/20180912/111.xls";
27         //每次讀READ_INDEX的量
28         File file = new File(localPath);
29         List<List<Object>> list = new ArrayList<>();
30         int i = 0;
31         while (true) {
32             //若是是讀到下一行爲空
33             //每一行的list
34             List<Object> rowList = readRow(file, i++);
35             if (rowList != null) {
36                 list.add(rowList);
37             } else {
38                 System.out.println("===================退出導入=============");
39                 System.out.println("===================保存剩下的=============" + i);
40                 //作保存動做
41                 list.clear();
42                 break;
43             }
44             if (list.size() == READ_INDEX) {
45                 //作保存動做
46                 System.out.println("===================保存=============" + i);
47                 list.clear();
48             }
49         }
50     }
51 
52     public static List<Object> readRow(File file, int rowNum) throws Exception {
53         FileInputStream inputStream = new FileInputStream(file);
54         HSSFWorkbook book = new HSSFWorkbook(inputStream);
55         Sheet sheet = book.getSheetAt(0);//sheet 從0開始
56         List<Object> list = new ArrayList<>();
57         Row row = sheet.getRow(rowNum);
58         if (!isRowEmpty(row)) {
59             for (int j = 0; j < row.getLastCellNum(); j++) {//列循環開始,從第0列開始
60                 Cell cell = row.getCell(j);
61                 if (cell == null) {
62                     continue;
63                 }
64                 String cellValue;
65                 if (ExcelUtils.isMergedRegion(sheet, cell)) {
66                     cellValue = ExcelUtils.getMergedRegionValue(sheet, cell);
67                 } else {
68                     cellValue = ExcelUtils.getCellValue(cell);
69                 }
70                 list.add(cellValue);
71                 //System.out.print(cellValue.concat("   |  "));
72             }
73             //System.out.println();
74         } else {
75             return null;
76         }
77 
78         return list;
79     }
80 
81     /**
82      * 判斷是否爲空行
83      *
84      * @param row
85      * @return
86      */
87     public static boolean isRowEmpty(Row row) {
88         if (row == null) {
89             return true;
90         }
91         for (int c = row.getFirstCellNum(); c < row.getLastCellNum(); c++) {
92             Cell cell = row.getCell(c);
93             if (cell != null && cell.getCellType() != Cell.CELL_TYPE_BLANK)
94                 return false;
95         }
96         return true;
97     }
98 
99 }