JAVA instances Excel spreadsheet format to read and write xls

Project directory

file

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">
    <parent>
        <artifactId>helloworld</artifactId>
        <groupId>com.ydfind</groupId>
        <version>1.0-SNAPSHOT</version>
    </parent>
    <modelVersion>4.0.0</modelVersion>

    <artifactId>excel-demo</artifactId>

    <build>
        <resources>
            <resource>
                <directory>src/main/resources</directory>
                <filtering>true</filtering>
            </resource>
        </resources>
    </build>

    <dependencies>
        <!-- 日志 -->
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.16.20</version>
        </dependency>
        <dependency>
            <groupId>org.slf4j</groupId>
            <artifactId>slf4j-simple</artifactId>
            <version>1.7.25</version>
        </dependency>
        <!-- xml依赖 -->
        <dependency>
            <groupId>org.apache.poi</groupId>
            <artifactId>poi</artifactId>
            <version>3.8</version>
        </dependency>
        <dependency>
            <groupId>org.apache.poi</groupId>
            <artifactId>poi-ooxml</artifactId>
            <version>3.8</version>
        </dependency>
        <!-- test -->
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.12</version>
            <scope>test</scope>
        </dependency>
    </dependencies>

</project>

ExcelReadWrite.java

package com.ydfind.excel;

import lombok.extern.slf4j.Slf4j;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
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 java.io.*;
import java.util.Objects;

@Slf4j
public class ExcelReadWrite {

    /**
     * 通过复制格子的形式，作为读写的例子
     * 将excel文件sourceFilename的内容，复制到targetFilename
     * @param sourceFilename
     * @param targetFilename
     */
    public static void copyExcel(String sourceFilename, String targetFilename) throws IOException {
        FileInputStream inputStream = null;
        FileOutputStream outputStream = null;
        try{
            log.info("start to copy excel from {} to {}", sourceFilename, targetFilename);
            // 源文件
            File inFile = new File(sourceFilename);
            inputStream = new FileInputStream(inFile);
            Workbook inWork = new HSSFWorkbook(inputStream);
            // 目标
            File outFile = new File(targetFilename);
            outputStream = new FileOutputStream(outFile);
            Workbook outWork = new HSSFWorkbook();
            // 复制
            copyExcel(inWork, outWork);
            // 保存到目标文件
            outWork.write(outputStream);
            log.info("copy success");
        }finally {
            if(outputStream != null){
                try {
                    outputStream.close();
                }catch (Exception e){
                    log.warn("outputStream close error!");
                }
            }
            if(inputStream != null) {
                try {
                    inputStream.close();
                } catch (Exception e) {
                    log.warn("inputStream close error!");
                }
            }
        }
    }

    private static void copyExcel(Workbook source, Workbook target){
        // 遍历复制
        int sheetCount = source.getNumberOfSheets();
        for(int i = 0; i < sheetCount; i++){
            Sheet inSheet = source.getSheetAt(i);
            Sheet outSheet = target.createSheet(inSheet.getSheetName());
            int rowCount = inSheet.getLastRowNum() + 1;
            for(int j = 0; j < rowCount; j++){
                Row inRow = inSheet.getRow(j);
                Row outRow = outSheet.createRow(j);
                if(Objects.isNull(inRow)){
                    continue;
                }
                int colNum = inRow.getLastCellNum() + 1;
                for(int coli = 0; coli < colNum; coli++){
                    Cell inCell = inRow.getCell(coli);
                    Cell outCell = outRow.createCell(coli);
                    if(Objects.isNull(inCell)){
                        continue;
                    }
                    String text = inCell.toString();
                    if(Objects.isNull(text)){
                        continue;
                    }
                    outCell.setCellValue(text.trim());
                }
            }
        }
    }
}

FileUtil.java

package com.ydfind.util;

import lombok.extern.slf4j.Slf4j;

import java.io.*;

@Slf4j
public class FileUtil {

    public static void writeFile(String path, String str) throws IOException {
        try {
            File file = new File(path);
            if(!file.exists()) {
                file.createNewFile();
            }
            FileOutputStream out = new FileOutputStream(file);
            StringBuffer sb = new StringBuffer();
            sb.append(str + "\r\n");
            out.write(sb.toString().getBytes("utf-8"));
            out.close();
        } catch(IOException ex) {
            throw new IOException("writeFile " + path + " error", ex);
        }
    }

    public static String readFile(String path) throws IOException {
        return readFile(path, "utf-8");
    }

    public static String readFile(String path, String encode) throws IOException {
        StringBuffer sb=new StringBuffer();
        String tempstr=null;
        try {
            File file=new File(path);
            if(!file.exists()) {
                throw new FileNotFoundException();
            }
            FileInputStream fis=new FileInputStream(file);
            BufferedReader br=new BufferedReader(new InputStreamReader(fis, encode));
            while((tempstr=br.readLine())!=null) {
                sb.append(tempstr + "\r\n");
            }
        } catch(IOException ex) {
            throw new IOException("readFile " + path + " error", ex);
        }
        return sb.toString();
    }

}

ExcelReadWriteTest.java

import com.ydfind.excel.ExcelReadWrite;
import lombok.extern.slf4j.Slf4j;
import org.junit.Test;

import java.io.IOException;

@Slf4j
public class ExcelReadWriteTest {

    @Test
    public void testCopyExcel() throws IOException {
        String source = ExcelReadWriteTest.class.getClassLoader().getResource("source.xls").getFile();
        String target = ExcelReadWriteTest.class.getClassLoader().getResource("target.xls").getFile();
        ExcelReadWrite.copyExcel(source, target);
        log.info("打开 \".\\excel-demo\\target\\test-classes\\target.xls\", 查看是否复制成功！");
    }
}

test

Two new excel file, the resource into the test folder (can also be placed elsewhere, absolute path), run the test, you can copy the contents of the target.xls in source.xls