java 实现导出excel报表

1.场景描述

　　使用java实现导出excel报表。使用Apache POI。

　　Apache POI是Apache软件基金会的开源项目，POI提供API给Java程序对Microsoft Office格式档案读和写的功能。

2.Maven依赖

<dependency>
    <groupId>org.apache.poi</groupId>
    <artifactId>poi</artifactId>
    <version>3.9</version>
</dependency>
<dependency>
     <groupId>org.apache.poi</groupId>
    <artifactId>poi-ooxml</artifactId>
    <version>3.9</version>
</dependency>
<dependency>
    <groupId>commons-lang</groupId>
    <artifactId>commons-lang</artifactId>
    <version>2.3</version>
</dependency>

3.代码编写

3.1导出报表类

import com.nnkc.util.ExcelUtil;
import org.apache.commons.lang.StringUtils;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.xssf.streaming.SXSSFWorkbook;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.OutputStream;
import java.net.URLEncoder;
import java.util.List;

/**
 *功能描述：导出报表
 */
public class ReportExcel {
    /**
     * 功能: Excel导出公共方法
     * 记录条数大于50000时 导出.xlsx文件(excel07+)  小于等于50000时导出 .xls文件(excel97-03)
     * 开发：wangkecheng
     * @param list            需要导出的列表数据
     * @param title            导出文件的标题
     * @param className        导出对象的类名
     * @param exportType    针对同一个pojo可能有多个不同的导出模板时,可以通过此属性来决定导出哪一套模板，默认第一套
     * @param response         用来获取输出流
     * @param request       针对火狐浏览器导出时文件名乱码的问题,也可以不传入此值
     * @throws IOException
     */
    public void excelExport(List list, String title, Class className, Integer exportType, HttpServletResponse response, HttpServletRequest request) throws IOException {
        OutputStream out = response.getOutputStream();
        try {
            ExcelUtil excel = new ExcelUtil();
            if(list!=null && list.size()>ExcelUtil.EXPORT_07_LEAST_SIZE){
                dealBigNumber(list, title, className, exportType, response, request, out, excel);
            }else{
                HSSFWorkbook hss = new HSSFWorkbook();
                if(exportType==null){
                    hss = excel.exportExcel(list,title,className,0);
                }else{
                    hss = excel.exportExcel(list, title, className, exportType);
                }
                String disposition = "attachment;filename=";
                if(request!=null&&request.getHeader("USER-AGENT")!=null&& StringUtils.contains(request.getHeader("USER-AGENT"), "Firefox")){
                    disposition += new String((title+".xls").getBytes(),"ISO8859-1");
                }else{
                    disposition += URLEncoder.encode(title+".xls", "UTF-8");
                }

                response.setContentType("application/vnd.ms-excel;charset=UTF-8");
                response.setHeader("Content-disposition", disposition);
                hss.write(out);
            }
        } catch (Exception e) {
            System.out.println(e.getMessage());
        } finally {
            out.close();
        }
    }

    private void dealBigNumber(List list, String title, Class className, Integer exportType,
                               HttpServletResponse response, HttpServletRequest request, OutputStream out, ExcelUtil excel)
            throws Exception{
        SXSSFWorkbook hss;
        if(exportType==null){
            hss = excel.exportExcel07S(list,title,className,0);
        }else{
            hss = excel.exportExcel07S(list, title, className, exportType);
        }

        String disposition = "attachment;filename=";
        if(request!=null && request.getHeader("USER-AGENT") != null && StringUtils.contains(request.getHeader("USER-AGENT"), "Firefox")){
            disposition += new String((title+".xlsx").getBytes(),"ISO8859-1");
        }else{
            disposition += URLEncoder.encode(title+".xlsx", "UTF-8");
        }

        response.setContentType("application/vnd.openxmlformats-officedocument.spreadsheetml.sheet;charset=UTF-8");
        response.setHeader("Content-disposition", disposition);
        hss.write(out);
    }
}

3.2工具类

import org.apache.poi.hssf.usermodel.*;
import org.apache.poi.hssf.util.HSSFColor;
import org.apache.poi.ss.usermodel.*;
import org.apache.poi.ss.util.CellRangeAddress;
import org.apache.poi.xssf.streaming.SXSSFWorkbook;
import org.apache.poi.xssf.usermodel.XSSFRichTextString;

import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.text.SimpleDateFormat;
import java.util.*;


/**
 * excel工具类
 * @author wangkecheng
 * @param <T>
 */
public class ExcelUtil<T> {

    public static final int EXPORT_07_LEAST_SIZE = 50000;
    /**
     * 功能 :获取表单导出数据
     * 开发：wangkecheng
     * @param list        数据列表
     * @param title     首行标题
     * @param className 实体对象class
     * @param exportType         模板标号
     * @return
     * @throws Exception
     */
    public HSSFWorkbook exportExcel(List<T> list, String title, Class className,Integer exportType) throws Exception {
        // 获取属性
        Field[] fields = className.getDeclaredFields();
        List<Field> fieldList = new ArrayList<Field>();
        for (Field fie : fields) {
            if (fie.isAnnotationPresent(ExcelAnnotation.class)) {
                fieldList.add(fie);
            }
        }
        // 按照id进行排序
        Collections.sort(fieldList, new Comparator<Field>() {
            public int compare(Field f1, Field f2) {
                return f1.getAnnotation(ExcelAnnotation.class).id() - f2.getAnnotation(ExcelAnnotation.class).id();
            }
        });
        int columnsize = fieldList.size(), rowindex = 0;
        // 创建一个HSSFWorbook对象（excel的文档对象）
        HSSFWorkbook hWorkbook = new HSSFWorkbook();
        // 创建一个HSSFSheet对象（excll的表单）
        HSSFSheet hSheet = hWorkbook.createSheet();
        // 创建行（excel的行）
        HSSFRow hRow = hSheet.createRow(rowindex++);
        //设置行高度
        hRow.setHeight((short)380);
        // 创建单元格（从0开始）
        HSSFCell hCell = hRow.createCell((short) 0);
        //样式对象
        HSSFCellStyle cellStyle = getCellStyle(hWorkbook, (short) 300, (short) 500);
        // 将上面获得的样式对象给对应单元格
        hCell.setCellStyle(cellStyle);
        //设置标题行
        hCell.setCellValue(title);

        if (getHuoResult(fieldList.isEmpty(),list == null,list.isEmpty())) {
            return hWorkbook;
        }

        //创建第二行，代表列名
        hRow = hSheet.createRow(rowindex++);
        cellStyle = getCellStyle(hWorkbook, (short) 270, (short) 500);
        generateTitle(exportType, fieldList, columnsize, hSheet, hRow, cellStyle);

        //组装excel的数据
        cellStyle = getCellStyle(hWorkbook, (short) 220, (short) 500);// 设置单元格格式
        generateData(list, fieldList, columnsize, rowindex, hSheet, cellStyle);

        /**
         * 第1个参数：从哪一行开始
         * 第2个参数：到哪一行结束
         * 第3个参数：从哪一列开始
         * 第4个参数：到哪一列结束
         */
        hSheet.addMergedRegion(new CellRangeAddress(0,0,0,columnsize-1));

        // 固定表头（前一个参数代表列，后一个参数单表行）
        hSheet.createFreezePane(0, 1);
        return hWorkbook;
    }

    /**
     * 功能：組裝列明
     * @param exportType 模板编号
     * @param fieldList 列名
     * @param columnsize 列数
     * @param hSheet sheet页
     * @param hRow  行
     * @param cellStyle 样式
     */
    private void generateTitle(Integer exportType, List<Field> fieldList, int columnsize, HSSFSheet hSheet, HSSFRow hRow,
            HSSFCellStyle cellStyle) {
        HSSFCell hCell;
        for (int i = 0; i < columnsize; i++) {
            Field field = fieldList.get(i);
            if (field.isAnnotationPresent(ExcelAnnotation.class)) {
                // 获取该字段的注解对象
                ExcelAnnotation anno = field.getAnnotation(ExcelAnnotation.class);
                hCell = hRow.createCell((short) i);
                String colName = field.getAnnotation(ExcelAnnotation.class).name().length>exportType
                                ?field.getAnnotation(ExcelAnnotation.class).name()[exportType]
                                :field.getAnnotation(ExcelAnnotation.class).name()[0];
                hCell.setCellValue(colName);
                hCell.setCellStyle(cellStyle);
                hSheet.setColumnWidth((short) i, (short) anno.width());
            }
        }
    }

    /**
     * 组装excel的数据
     * @param list 具体数据
     * @param fieldList 列名
     * @param columnsize 列数
     * @param rowindex 行数计数
     * @param hSheet sheet页
     * @param cellStyle 样式
     * @return
     * @throws NoSuchMethodException
     * @throws IllegalAccessException
     * @throws InvocationTargetException
     */
    private int generateData(List<T> list, List<Field> fieldList, int columnsize, int rowindex, HSSFSheet hSheet,
            HSSFCellStyle cellStyle) throws NoSuchMethodException, IllegalAccessException, InvocationTargetException {
        HSSFRow hRow;
        HSSFCell hCell;
        for (Object model : list) {
            hRow = hSheet.createRow(rowindex++);
            //获取该类
            Class clazz = model.getClass();
            for (int i = 0; i < columnsize; i++) {
                Field field =fieldList.get(i);
                //获取方法名
                String methodName = "get" + field.getName().substring(0, 1).toUpperCase()+field.getName().substring(1);
                Method method = clazz.getMethod(methodName);
                try {
                    // 获取该字段的注解对象
                    Object result = method.invoke(model);
                    hCell = hRow.createCell((short) i);
                    if (result != null) {
                        if (result.getClass().isAssignableFrom(Date.class)) {
                            SimpleDateFormat format = new SimpleDateFormat("yyyy年MM月dd日");
                            result = format.format(result);
                        }
                        hCell.setCellValue(new HSSFRichTextString(result.toString()));
                    } else {
                        hCell.setCellValue(new HSSFRichTextString("-"));
                    }
                    hCell.setCellStyle(cellStyle);
                } catch (IllegalArgumentException e) {
                    System.out.println(e.getMessage());
                }
            }
        }
        return rowindex;
    }
    /**
     * 生成07格式的excel对象 使用流方式防止内存溢出
     * @param list
     * @param title
     * @param className
     * @param exportType
     * @return
     * @throws Exception
     */
    public SXSSFWorkbook exportExcel07S(List<T> list, String title, Class className,Integer exportType) throws Exception {
        // 获取属性
        Field[] fields = className.getDeclaredFields();
        List<Field> fieldList = new ArrayList<Field>();
        for (Field fie : fields) {
            if (fie.isAnnotationPresent(ExcelAnnotation.class)){
                fieldList.add(fie);
            }
        }
        // 按照id进行排序
        Collections.sort(fieldList, new Comparator<Field>() {
            public int compare(Field f1, Field f2) {
                return f1.getAnnotation(ExcelAnnotation.class).id() - f2.getAnnotation(ExcelAnnotation.class).id();
            }
        });

        int columnsize = fieldList.size(), rowindex = 0;
        // 创建一个HSSFWorbook对象s
        SXSSFWorkbook hWorkbook = new SXSSFWorkbook();
        // 创建一个HSSFSheet对象（sheet页）
        Sheet hSheet =  hWorkbook.createSheet();
        // 创建第一行(此行作为头)
        Row hRow = hSheet.createRow(rowindex++);
        hRow.setHeight((short)380);
        // 创建单元格（第一（0）个）
        Cell hCell = hRow.createCell((short) 0);
        // 设置样式
        CellStyle cellStyle = getCellStyle07S(hWorkbook, (short) 300, (short) 500);
        // 将上面获得的样式对象给对应单元格
        hCell.setCellStyle(cellStyle);
        //设置标题行
        hCell.setCellValue(title);

        if (getHuoResult(fieldList.isEmpty(),list == null,list.isEmpty())) {
            return hWorkbook;
        }

        // 创建第二列，列名
        hRow = hSheet.createRow(rowindex++);
        cellStyle = getCellStyle07S(hWorkbook, (short) 270, (short) 500);
        createTitle07S(exportType, fieldList, columnsize, hSheet, hRow, cellStyle);

        //生成数据
        cellStyle = getCellStyle07S(hWorkbook, (short) 220, (short) 500);// 设置单元格格式
        dealCreateRow07S(list, fieldList, columnsize, rowindex, hSheet, cellStyle);

        /**
         * 第1个参数：从哪一行开始
         * 第2个参数：到哪一行结束
         * 第3个参数：从哪一列开始
         * 第4个参数：到哪一列结束
         */
        hSheet.addMergedRegion(new CellRangeAddress(0,0,0,columnsize-1));

        // 固定表头（前一个参数代表列，后一个参数单表行）
        hSheet.createFreezePane(0, 1);
        return hWorkbook;
    }

    private int dealCreateRow07S(List<T> list, List<Field> fieldList, int columnsize, int rowindex, Sheet hSheet,
            CellStyle cellStyle) throws NoSuchMethodException, IllegalAccessException, InvocationTargetException {
        Row hRow;
        Cell hCell;
        for (Object model : list) {
            hRow = hSheet.createRow(rowindex++);
            // 获取该类 并获取自身方法
            Class clazz = model.getClass();
            for (int i = 0; i < columnsize; i++) {
                Field field = fieldList.get(i);
                String methodName = "get" + field.getName().substring(0, 1).toUpperCase()
                + field.getName().substring(1);
                Method method = clazz.getMethod(methodName);
                try {
                    // 获取该字段的注解对象
                    Object result = method.invoke(model);
                    hCell = hRow.createCell((short) i);
                    if (result != null) {
                        if (result.getClass().isAssignableFrom(Date.class)) {
                            SimpleDateFormat format = new SimpleDateFormat("yyyy年MM月dd日");
                            result = format.format(result);
                        }
                        hCell.setCellValue(new XSSFRichTextString(result.toString()));
                    } else {
                        hCell.setCellValue(new XSSFRichTextString("-"));
                    }
                    hCell.setCellStyle(cellStyle);
                } catch (IllegalArgumentException e) {
                    System.out.println(e.getMessage());
                }
            }
        }
        return rowindex;
    }

    /**
     * 生成列名
     * @param exportType 模板编号
     * @param fieldList 列名
     * @param columnsize 列数
     * @param hSheet
     * @param hRow
     * @param cellStyle
     */
    private void createTitle07S(Integer exportType, List<Field> fieldList, int columnsize, Sheet hSheet, Row hRow,
            CellStyle cellStyle) {
        Cell hCell;
        for (int i = 0; i < columnsize; i++) {
            Field field = (Field) fieldList.get(i);
            if (field.isAnnotationPresent(ExcelAnnotation.class)) {
                // 获取该字段的注解对象
                ExcelAnnotation anno = field.getAnnotation(ExcelAnnotation.class);
                hCell = hRow.createCell((short) i);
                String colName = field.getAnnotation(ExcelAnnotation.class).name().length>exportType
                ?field.getAnnotation(ExcelAnnotation.class).name()[exportType]
                                                                   :field.getAnnotation(ExcelAnnotation.class).name()[0];
                hCell.setCellValue(colName);
                hCell.setCellStyle(cellStyle);
                hSheet.setColumnWidth((short) i, (short) anno.width());
            }
        }
    }

    /**
     * 功能 :设置excel表格默认样式
     * @param hWorkbook     需导出Excel数据
     * @param fontHeight     字体粗度
     * @param boldWeight    表格线的粗度
     * @return
     */
    public HSSFCellStyle getCellStyle(HSSFWorkbook hWorkbook, short fontHeight, short boldWeight) {
        HSSFCellStyle cellStyle;
        HSSFFont font;
        cellStyle = hWorkbook.createCellStyle();
        cellStyle.setBorderBottom(HSSFCellStyle.BORDER_THIN);
        cellStyle.setBorderLeft(HSSFCellStyle.BORDER_THIN);
        cellStyle.setBorderRight(HSSFCellStyle.BORDER_THIN);
        cellStyle.setBorderTop(HSSFCellStyle.BORDER_THIN);
        cellStyle.setTopBorderColor(HSSFColor.BLACK.index);
        cellStyle.setLeftBorderColor(HSSFColor.BLACK.index);
        cellStyle.setRightBorderColor(HSSFColor.BLACK.index);
        cellStyle.setBottomBorderColor(HSSFColor.BLACK.index);
        font = hWorkbook.createFont();
        font.setFontHeight(fontHeight);
        font.setBoldweight(boldWeight);
        font.setFontName("宋体");
        cellStyle.setFont(font);
        cellStyle.setWrapText(true);
        cellStyle.setAlignment(HSSFCellStyle.ALIGN_CENTER);
        cellStyle.setVerticalAlignment(HSSFCellStyle.VERTICAL_CENTER);
        return cellStyle;
    }

    /**
     * 功能 :设置excel 07表格默认样式
     * @param hWorkbook     需导出Excel数据
     * @param fontHeight     字体粗度
     * @param boldWeight    表格线的粗度
     * @return
     */
    public CellStyle getCellStyle07S(SXSSFWorkbook hWorkbook, short fontHeight, short boldWeight) {
        CellStyle cellStyle;
        Font font;
        cellStyle = hWorkbook.createCellStyle();
        cellStyle.setBorderBottom(HSSFCellStyle.BORDER_THIN);
        cellStyle.setBorderLeft(HSSFCellStyle.BORDER_THIN);
        cellStyle.setBorderRight(HSSFCellStyle.BORDER_THIN);
        cellStyle.setBorderTop(HSSFCellStyle.BORDER_THIN);
        cellStyle.setTopBorderColor(HSSFColor.BLACK.index);
        cellStyle.setLeftBorderColor(HSSFColor.BLACK.index);
        cellStyle.setRightBorderColor(HSSFColor.BLACK.index);
        cellStyle.setBottomBorderColor(HSSFColor.BLACK.index);
        font = hWorkbook.createFont();
        font.setFontHeight(fontHeight);
        font.setBoldweight(boldWeight);
        font.setFontName("宋体");
        cellStyle.setFont(font);
        cellStyle.setWrapText(true);
        cellStyle.setAlignment(HSSFCellStyle.ALIGN_CENTER);
        cellStyle.setVerticalAlignment(HSSFCellStyle.VERTICAL_CENTER);
        return cellStyle;
    }

    /*
     * 获取或运算结果
     */
    private static boolean getHuoResult(Boolean... bs){
        for(boolean b:bs){
            if(b){
                return b;
            }
        }
        return false;
     }
}

3.3注解类

import java.lang.annotation.*;


/**
 * <p>
 *  功能：excel模板设置
 * </p>
 */
@Documented  
@Retention(RetentionPolicy.RUNTIME)  
@Target(ElementType.FIELD)
public @interface ExcelAnnotation {
    //Excel列ID(Excel列排序序号)
    int id();
    //Excel列名
    String[] name();
    //Excel列宽
    int width() default 5000;
}

3.4pojo对象

import com.nnkc.util.ExcelAnnotation;

import java.util.Date;

/**
 * Created by chengcheng on 2017/12/5.
 */
public class Product {

    @ExcelAnnotation(id=1,name={"产品名称","商品名称"},width = 5000)
    private String name;
    @ExcelAnnotation(id=2,name={"产品价格","商品价格"},width = 5000)
    private double price;
    @ExcelAnnotation(id=3,name={"生产日期"},width = 5000)
    private Date date;

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public double getPrice() {
        return price;
    }

    public void setPrice(double price) {
        this.price = price;
    }

    public Date getDate() {
        return date;
    }

    public void setDate(Date date) {
        this.date = date;
    }
}

3.5测试类

import com.nnkc.pojo.Product;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;

/**
 * Created by chengcheng on 2017/12/5.
 */
public class ReportExcelTest extends HttpServlet {

    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        System.out.println("调用成功");
    }

    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        List<Product> list = new ArrayList<Product>();

        for (int i = 0 ; i<60000 ; i++) {
            //组装测试数据
            Product product = new Product();
            product.setName("爱奇艺会员"+i);
            product.setPrice(9.99);
            product.setDate(new Date());
            list.add(product);
        }

        ReportExcel reportExcel = new ReportExcel();
        reportExcel.excelExport(list,"测试",Product.class,1,resp,req);
    }
}

3.5测试结果

4.特别说明

源码仓库地址：https://github.com/nn-kc/reportexcel.git