首先,jar

maven 添加依赖

<!-- https://mvnrepository.com/artifact/org.apache.poi/poi-ooxml --><dependency> <groupId>org.apache.poi</groupId> <artifactId>poi-ooxml</artifactId> <version>3.15</version></dependency>

开始以为是poi，然后就直接加poi的依赖，谁知道并没有所需要的类。查了查才发现是poi-ooxml

要用到的类

XSSFWorkbook ， 代表一个excel文档

XSSFSheet ， 代表文档中的一个sheet

XSSFRow ， 代表sheet中的一行

XSSFCell ， 代表row中的每一项的值

最最基本的使用

//创建excel文档XSSFWorkbook workbook = new XSSFWorkbook();//创建sheetXSSFSheet sheet = workbook.createSheet("sheetName");int rownum=0;//创建首行XSSFRow firstrow = sheet.createRow(rownum++);int cellnum = 0;//把保存在titles中的各个列名，分别在row中创建cellfor(String key : titles){ XSSFCell cell = firstrow.createCell(cellnum++); cell.setCellValue(key);}//下面可以继续创建行//把excel写到要写的outputStream中workbook.write(output);//最后关闭workbook.close();

小例子一枚

利用反射，把bean类中各属性（用getXxx取出），写入到excel中

ExcelUtil.java

package me.paul.excelDemo;import java.io.IOException;import java.io.OutputStream;import java.lang.reflect.InvocationTargetException;import java.lang.reflect.Method;import java.util.LinkedHashMap;import java.util.List;import java.util.Map;import java.util.regex.Matcher;import java.util.regex.Pattern;import org.apache.poi.xssf.usermodel.XSSFCell;import org.apache.poi.xssf.usermodel.XSSFRow;import org.apache.poi.xssf.usermodel.XSSFSheet;import org.apache.poi.xssf.usermodel.XSSFWorkbook;public class ExcelUtil { public <T> void getExcel(List<T> list,Class<T> c,OutputStream output) throws IOException, IllegalAccessException, IllegalArgumentException, InvocationTargetException{ Map<String,Method> methodMap = new LinkedHashMap<>(); Method[] methods = c.getDeclaredMethods(); for(int i=0;i<methods.length;i++){ Method method = methods[i]; String name = method.getName(); Pattern pattern = Pattern.compile("get(.*)"); Matcher matcher = null; if((matcher = pattern.matcher(name)).matches()){ name = matcher.group(1); char ch = name.charAt(0); char newch = (char) (ch + 32); name = name.replace(ch,newch); methodMap.put(name, method); } } XSSFWorkbook workbook = new XSSFWorkbook(); XSSFSheet sheet = workbook.createSheet(c.getCanonicalName()); int rownum=0; XSSFRow firstrow = sheet.createRow(rownum++); int cellnum = 0; for(String key : methodMap.keySet()){ XSSFCell cell = firstrow.createCell(cellnum++); cell.setCellValue(key); } for(T t : list){ XSSFRow row = sheet.createRow(rownum++); cellnum = 0; for(String key:methodMap.keySet()){ Method method = methodMap.get(key); //设置可访问，之前不知道这方法，所以关于反射那篇文章有错误，见谅见谅 method.setAccessible(true); Object obj = method.invoke(t); XSSFCell cell = row.createCell(cellnum++); cell.setCellValue(obj== null ? "":obj.toString()); } } workbook.write(output); workbook.close(); } }

App.java 进行测试使用

package me.paul.excelDemo;import java.io.FileOutputStream;import java.io.IOException;import java.io.OutputStream;import java.lang.reflect.InvocationTargetException;import java.util.ArrayList;import java.util.List;public class App { public static void main(String[] args) throws IllegalAccessException, IllegalArgumentException, InvocationTargetException, IOException { List<User> list = new ArrayList<>(); User u = new User(); u.setId(1); u.setName("Paul"); u.setAge(18); list.add(u); u = new User(); u.setId(2); u.setName("Johnson"); u.setAge(20); list.add(u); u = new User(); u.setId(3); u.setName("David"); u.setAge(22); list.add(u); OutputStream output = new FileOutputStream("/home/paul/user.xlsx"); new ExcelUtil().getExcel(list, User.class,output); output.close(); }}

测试结果截图

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持。