引入相关依赖
<!--数据导出excel-->
<!-- https://mvnrepository.com/artifact/org.apache.poi/poi -->
<dependency>
<groupId>org.apache.poi</groupId>
<artifactId>poi</artifactId>
<version>3.17</version>
</dependency>
<!-- https://mvnrepository.com/artifact/org.apache.poi/poi-ooxml -->
<dependency>
<groupId>org.apache.poi</groupId>
<artifactId>poi-ooxml</artifactId>
<version>3.17</version>
</dependency>
<!-- https://mvnrepository.com/artifact/org.apache.poi/poi-ooxml-schemas -->
<dependency>
<groupId>org.apache.poi</groupId>
<artifactId>poi-ooxml-schemas</artifactId>
<version>3.17</version>
</dependency>Controller
package com.huang.controller;
import com.huang.mapper.UsersMapper;
import com.huang.util.excelExport.ExcelExport2;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import javax.annotation.Resource;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
/**
* @Author：huang
* @Date：2019-09-21 13:13
* @Description：<描述>
*/
@Controller
public class TestController {
@Resource
private UsersMapper usersMapper;
@RequestMapping("/test")
public void testExprotExcel(HttpServletResponse response){
String[] arr = new String[]{"ID","用户名","账号","密码","备注"};
ExcelExport2.export(response,usersMapper.selectAll(),arr);
}
}
工具类
文件导出excel工具类
package com.huang.util.excelExport;
import org.apache.poi.hssf.usermodel.*;
import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.CellType;
import org.apache.poi.ss.usermodel.Row;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.List;
/**
* @Author：haung
* @Date：2019-09-21 11:21
* @Description：Excel导出工具类，依赖于ClassUtil工具类
*/
public final class ExcelExport2 {
/**
* 将传入的数据导出excel表并下载
* @param response 返回的HttpServletResponse
* @param importlist 要导出的对象的集合
* @param attributeNames 含有每个对象属性在excel表中对应的标题字符串的数组（请按对象中属性排序调整字符串在数组中的位置）
*/
public static void export(HttpServletResponse response, List<?> importlist, String[] attributeNames) {
//获取数据集
List<?> datalist = importlist;
//声明一个工作薄
HSSFWorkbook workbook = new HSSFWorkbook();
//生成一个表格
HSSFSheet sheet = workbook.createSheet();
//设置表格默认列宽度为15个字节
sheet.setDefaultColumnWidth((short) 18);
//获取字段名数组
String[] tableAttributeName = attributeNames;
//获取对象属性
Field[] fields = ClassUtil.getClassAttribute(importlist.get(0));
//获取对象get方法
List<Method> methodList = ClassUtil.getMethodGet(importlist.get(0));
//循环字段名数组，创建标题行
Row row = sheet.createRow(0);
for (int j = 0; j< tableAttributeName.length; j++){
//创建列
Cell cell = row.createCell(j);
//设置单元类型为String
cell.setCellType(CellType.STRING);
cell.setCellValue(transCellType(tableAttributeName[j]));
}
//创建普通行
for (int i = 0;i<datalist.size();i++){
//因为第一行已经用于创建标题行，故从第二行开始创建
row = sheet.createRow(i+1);
//如果是第一行就让其为标题行
Object targetObj = datalist.get(i);
for (int j = 0;j<fields.length;j++){
//创建列
Cell cell = row.createCell(j);
cell.setCellType(CellType.STRING);
//
try {
Object value = methodList.get(j).invoke(targetObj, new Object[]{});
cell.setCellValue(transCellType(value));
} catch (IllegalAccessException e) {
e.printStackTrace();
} catch (InvocationTargetException e) {
e.printStackTrace();
}
}
}
response.setContentType("application/octet-stream");
//默认Excel名称
response.setHeader("Content-Disposition", "attachment;fileName="+"test.xls");
try {
response.flushBuffer();
workbook.write(response.getOutputStream());
} catch (IOException e) {
e.printStackTrace();
}
}
private static String transCellType(Object value){
String str = null;
if (value instanceof Date){
Date date = (Date) value;
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
str = sdf.format(date);
}else{
str = String.valueOf(value);
if (str == "null"){
str = "";
}
}
return str;
}
}
类操作工具类
package com.huang.util.excelExport;
import org.springframework.stereotype.Component;
import java.lang.reflect.Field;
import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.List;
/**
* @Author：huang
* @Date：2019-09-21 13:41
* @Description：关于类的操作的工具类
*/
public final class ClassUtil {
private ClassUtil() {
throw new Error("工具类不允许实例化！");
}
/**
* 获取类属性
* @param targetObj 要获取属性的类
* @return 含有类属性的集合
*/
public static Field[] getClassAttribute(Object targetObj){
Class<?> objectClass = targetObj.getClass();
return objectClass.getDeclaredFields();
}
/**
* 获取对象的所有get或set方法
* @param targetObj 要获取属性的类
* @param methodKeyword get或者set关键字
* @return 含有类get或set方法的集合
*/
public static List<Method> getMethod(Object targetObj,String methodKeyword){
List<Method> methodList = new ArrayList<>();
Class<?> objectClass = targetObj.getClass();
Field[] field = objectClass.getDeclaredFields();
for (int i = 0;i<field.length;i++){
//获取属性名并组装方法名
String fieldName = field[i].getName();
String getMethodName = methodKeyword
+ fieldName.substring(0, 1).toUpperCase()
+ fieldName.substring(1);
try {
Method method = objectClass.getMethod(getMethodName,new Class[]{});
methodList.add(method);
} catch (NoSuchMethodException e) {
e.printStackTrace();
}
}
return methodList;
}
/**
* 获取对象的所有get方法
* @param targetObj 要获取属性的类
* @return 含有类方法的集合
*/
public static List<Method> getMethodGet(Object targetObj){
return getMethod(targetObj,"get");
}
/**
* 获取对象的所有set方法
* @param targetObj 要获取属性的类
* @return 含有类方法的集合
*/
public static List<Method> getMethodSet(Object targetObj){
return getMethod(targetObj,"set");
}
}
原文地址：https://www.cnblogs.com/Createsequence/p/11563460.html
时间： 2024-08-26 13:03:45