Excel：使用java進行對excel的讀取和寫入
阿新 • • 發佈：2018-12-12
excel：表格
可以作為一個數據庫使用
Pom.xml:
<?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>2.1.1.RELEASE</version> <relativePath/> <!-- lookup parent from repository --> </parent> <groupId>com.hczk</groupId> <artifactId>hczk</artifactId> <version>0.0.1-SNAPSHOT</version> <packaging>jar</packaging> <name>hczk</name> <description>Demo project for Spring Boot</description> <properties> <java.version>1.8</java.version> </properties> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-jdbc</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <dependency> <groupId>org.mybatis.spring.boot</groupId> <artifactId>mybatis-spring-boot-starter</artifactId> <version>1.3.2</version> </dependency> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <scope>runtime</scope> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-freemarker</artifactId> </dependency> <dependency> <groupId>org.apache.poi</groupId> <artifactId>poi-ooxml</artifactId> <version>3.14</version> </dependency> <dependency> <groupId>org.apache.poi</groupId> <artifactId>poi</artifactId> <version>3.16</version> </dependency> </dependencies> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> </plugins> </build> </project>
先在本地建立
E:/writeExcel.xlsx或者 E:\\hc.xls
然後進行java方操作
WriteExcel ：將資料寫入Excel
package com.hczk.controller; import java.io.File; import java.io.FileInputStream; import java.io.FileOutputStream; import java.io.IOException; import java.io.OutputStream; import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map; import org.apache.poi.ss.usermodel.Cell; 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.xssf.usermodel.XSSFWorkbook; import org.apache.poi.hssf.usermodel.HSSFWorkbook; /** * Created by Administrator on 2018/12/12 0012. */ public class WriteExcel { public static void main(String[] args) { Map<String, Object> dataMap = new HashMap<>(); dataMap.put("name", "張久風"); dataMap.put("age", 13); dataMap.put("score", 98); Map<String, Object> dataMap2 = new HashMap<>(); dataMap2.put("name", "張久yi"); dataMap2.put("age", 134); dataMap2.put("score", 298); List<Map> list = new ArrayList<>(); list.add(dataMap); list.add(dataMap2); writeExcel(list, dataMap.size(), "E:\\hc.xls"); } // dataMap.size()==cloumnCount 物件多少屬性 public static void writeExcel(List<Map> dataList, int cloumnCount, String finalXlsxPath) { OutputStream out = null; try { // 獲取總列數 int columnNumCount = cloumnCount; // 讀取Excel文件 File finalXlsxFile = new File(finalXlsxPath); Workbook workBook = getWorkbok(finalXlsxFile); // sheet 對應一個工作頁 Sheet sheet = workBook.getSheetAt(0); /** * 刪除原有資料，除了屬性列 */ int rowNumber = sheet.getLastRowNum();// 第一行從0開始算 // System.out.println("原始資料總行數，除屬性列：" + rowNumber); for (int i = 1; i <=rowNumber; i++) {//可能有漏網之魚 Row row = sheet.getRow(i); if (row != null) {//如果列為空，跳過 sheet.removeRow(row); } } // 建立檔案輸出流，輸出電子表格：這個必須有，否則你在sheet上做的任何操作都不會有效 out = new FileOutputStream(finalXlsxPath); workBook.write(out); //第一行 Row rows = sheet.createRow(0); Cell firsts = rows.createCell(0); firsts.setCellValue("name"); Cell seconds = rows.createCell(1); seconds.setCellValue("age"); Cell thirds = rows.createCell(2); thirds.setCellValue("score"); /** * 往Excel中寫新資料 */ for (int j = 0; j < dataList.size(); j++) { // 建立一行：從第二行開始，跳過屬性列 Row row = sheet.createRow(j + 1); // 得到要插入的每一條記錄 Map dataMap = dataList.get(j); String name = dataMap.get("name").toString(); int age = (int) dataMap.get("age"); int score = (int) dataMap.get("score"); for (int k = 0; k < columnNumCount; k++) { // 在一行內迴圈 Cell first = row.createCell(0); first.setCellValue(name); Cell second = row.createCell(1); second.setCellValue(age); Cell third = row.createCell(2); third.setCellValue(score); } } // 建立檔案輸出流，準備輸出電子表格：這個必須有，否則你在sheet上做的任何操作都不會有效 out = new FileOutputStream(finalXlsxPath); workBook.write(out); } catch (Exception e) { e.printStackTrace(); } finally { try { if (out != null) { out.flush(); out.close(); } } catch (IOException e) { e.printStackTrace(); } } // System.out.println("資料匯出成功"); } /** * 判斷Excel的版本,獲取Workbook * * @param //in * @param //filename * @return * @throws IOException */ // private static final String EXCEL_XLS = "xls"; // private static final String EXCEL_XLSX = "xlsx"; public static Workbook getWorkbok(File file) throws IOException { Workbook wb = null; FileInputStream in = new FileInputStream(file); if (file.getName().endsWith("xls")) { //Excel 2003 wb = new HSSFWorkbook(in); } else if (file.getName().endsWith("xlsx")) { // Excel 2007/2010 wb = new XSSFWorkbook(in); } return wb; } }
ReadExcel ：讀取Excel中的資料
package com.hczk.controller; import java.io.FileInputStream; import java.io.FileNotFoundException; import java.io.IOException; import java.io.InputStream; import java.util.ArrayList; import java.util.LinkedHashMap; import java.util.List; import java.util.Map; import java.util.Map.Entry; import org.apache.poi.ss.usermodel.Cell; import org.apache.poi.ss.usermodel.DateUtil; 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.xssf.usermodel.XSSFWorkbook; import org.apache.poi.hssf.usermodel.HSSFWorkbook; public class ReadExcel { public static void main(String[] args) { Workbook wb = null; Sheet sheet = null; Row row = null; List<Map<String, Object>> list = null; String cellData = null; String filePath = "E:\\hc.xls"; String columns[] = {"name", "age", "score"}; wb = readExcel(filePath); if (wb != null) { //用來存放表中資料 list = new ArrayList<>(); //獲取第一個sheet sheet = wb.getSheetAt(0); //獲取最大行數 int rownum = sheet.getPhysicalNumberOfRows(); //獲取第一行 row = sheet.getRow(0); //獲取最大列數 int colnum = row.getPhysicalNumberOfCells(); for (int i = 1; i < rownum; i++) { Map<String, Object> map = new LinkedHashMap<>(); row = sheet.getRow(i); if (row != null) { for (int j = 0; j < colnum; j++) { cellData = (String) getCellFormatValue(row.getCell(j)); map.put(columns[j], cellData); } } else { break; } list.add(map); } } //遍歷解析出來的list for (Map<String, Object> map : list) { for (Entry<String, Object> entry : map.entrySet()) { System.out.print(entry.getKey() + ":" + entry.getValue() + ";"); } System.out.println(); } } //讀取excel public static Workbook readExcel(String filePath) { Workbook wb = null; if (filePath == null) { return null; } String extString = filePath.substring(filePath.lastIndexOf(".")); InputStream is = null; try { is = new FileInputStream(filePath); if (".xls".equals(extString)) { return new HSSFWorkbook(is); } else if (".xlsx".equals(extString)) { return new XSSFWorkbook(is); } else { return null; } } catch (FileNotFoundException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } return wb; } public static Object getCellFormatValue(Cell cell) { Object cellValue = null; if (cell != null) { //判斷cell型別 switch (cell.getCellType()) { case Cell.CELL_TYPE_NUMERIC: { cellValue = String.valueOf(cell.getNumericCellValue()); break; } case Cell.CELL_TYPE_FORMULA: { //判斷cell是否為日期格式 if (DateUtil.isCellDateFormatted(cell)) { //轉換為日期格式YYYY-mm-dd cellValue = cell.getDateCellValue(); } else {//數字 cellValue = String.valueOf(cell.getNumericCellValue()); } break; } case Cell.CELL_TYPE_STRING: { cellValue = cell.getRichStringCellValue().getString(); break; } default: cellValue = ""; } } else { cellValue = ""; } return cellValue; } }
經實際檢驗，對xls、xlsx都操作有效
很nice！