Java怎么导出Excel
内容摘要
java实现Excel数据导出：（推荐：java视频教程）目前，比较常用的实现Java导入、导出Excel的技术有两种Jakarta POI和Java ExcelJakarta POI 是一套用于访问微软格式文档的Java API。J
文章正文
java实现Excel数据导出：（推荐：java视频教程）
目前，比较常用的实现Java导入、导出Excel的技术有两种Jakarta POI和Java Excel
Jakarta POI 是一套用于访问微软格式文档的Java API。Jakarta POI有很多组件组成，其中有用于操作Excel格式文件的HSSF和用于操作Word的HWPF，在各种组件中目前只有用于操作Excel的HSSF相对成熟。
Jakarta POI HSSF API组件
HSSF（用于操作Excel的组件）提供给用户使用的对象在rg.apache.poi.hssf.usermodel包中,主要部分包括Excel对象，样式和格式，还有辅助操作。有以下几种对象：
基本操作步骤
首先，理解一下一个Excel的文件的组织形式，一个Excel文件对应于一个workbook(HSSFWorkbook)，一个workbook可以有多个sheet（HSSFSheet）组成，一个sheet是由多个row（HSSFRow）组成，一个row是由多个cell（HSSFCell）组成。
基本操作步骤：
下面来看一个动态生成Excel文件的例子：
//创建HSSFWorkbook对象
HSSFWorkbook wb = new HSSFWorkbook();
//创建HSSFSheet对象
HSSFSheet sheet = wb.createSheet("sheet0");
//创建HSSFRow对象
HSSFRow row = sheet.createRow(0);
//创建HSSFCell对象
HSSFCell cell=row.createCell(0);
//设置单元格的值
cell.setCellValue("单元格中的中文");
//输出Excel文件
FileOutputStream output=new FileOutputStream("d:workbook.xls");
wkb.write(output);
output.flush();HSSF读取文件同样还是使用这几个对象，只是把相应的createXXX方法变成了getXXX方法即可。可见只要理解了其中原理，不管是读还是写亦或是特定格式都可以轻松实现，正所谓知其然更要知其所以然。
导出表格的工具类：
excelUtil:
package com.zhl.push.Utils;
import com.google.common.base.Strings;
import org.apache.poi.hssf.usermodel.*;
import org.apache.poi.hssf.util.HSSFColor;
import org.apache.poi.ss.usermodel.VerticalAlignment;
import org.apache.poi.ss.util.CellRangeAddress;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.OutputStream;
import java.math.BigDecimal;
import java.util.List;
import java.util.Map;
public class ExcelExportUtil {
//表头
private String title;
//各个列的表头
private String[] heardList;
//各个列的元素key值
private String[] heardKey;
//需要填充的数据信息
private List<Map> data;
//字体大小
private int fontSize = 14;
//行高
private int rowHeight = 30;
//列宽
private int columWidth = 200;
//工作表
private String sheetName = "sheet1";
public String getTitle() {
return title;
}
public void setTitle(String title) {
this.title = title;
}
public String[] getHeardList() {
return heardList;
}
public void setHeardList(String[] heardList) {
this.heardList = heardList;
}
public String[] getHeardKey() {
return heardKey;
}
public void setHeardKey(String[] heardKey) {
this.heardKey = heardKey;
}
public List<Map> getData() {
return data;
}
public void setData(List<Map> data) {
this.data = data;
}
public int getFontSize() {
return fontSize;
}
public void setFontSize(int fontSize) {
this.fontSize = fontSize;
}
public int getRowHeight() {
return rowHeight;
}
public void setRowHeight(int rowHeight) {
this.rowHeight = rowHeight;
}
public int getColumWidth() {
return columWidth;
}
public void setColumWidth(int columWidth) {
this.columWidth = columWidth;
}
public String getSheetName() {
return sheetName;
}
public void setSheetName(String sheetName) {
this.sheetName = sheetName;
}
/**
* 开始导出数据信息
*
*/
public byte[] exportExport(HttpServletRequest request, HttpServletResponse response) throws IOException {
//检查参数配置信息
checkConfig();
//创建工作簿
HSSFWorkbook wb = new HSSFWorkbook();
//创建工作表
HSSFSheet wbSheet = wb.createSheet(this.sheetName);
//设置默认行宽
wbSheet.setDefaultColumnWidth(20);
// 标题样式（加粗，垂直居中）
HSSFCellStyle cellStyle = wb.createCellStyle();
cellStyle.setAlignment(HSSFCellStyle.ALIGN_CENTER);//水平居中
cellStyle.setVerticalAlignment(VerticalAlignment.CENTER);//垂直居中
HSSFFont fontStyle = wb.createFont();
fontStyle.setBoldweight(HSSFFont.BOLDWEIGHT_BOLD);
fontStyle.setBold(true); //加粗
fontStyle.setFontHeightInPoints((short)16); //设置标题字体大小
cellStyle.setFont(fontStyle);
//在第0行创建rows (表标题)
HSSFRow title = wbSheet.createRow((int) 0);
title.setHeightInPoints(30);//行高
HSSFCell cellValue = title.createCell(0);
cellValue.setCellValue(this.title);
cellValue.setCellStyle(cellStyle);
wbSheet.addMergedRegion(new CellRangeAddress(0,0,0,(this.heardList.length-1)));
//设置表头样式，表头居中
HSSFCellStyle style = wb.createCellStyle();
//设置单元格样式
style.setAlignment(HSSFCellStyle.ALIGN_CENTER);
style.setVerticalAlignment(HSSFCellStyle.VERTICAL_CENTER);
//设置字体
HSSFFont font = wb.createFont();
font.setFontHeightInPoints((short) this.fontSize);
style.setFont(font);
//在第1行创建rows
HSSFRow row = wbSheet.createRow((int) 1);
//设置列头元素
HSSFCell cellHead = null;
for (int i = 0; i < heardList.length; i++) {
cellHead = row.createCell(i);
cellHead.setCellValue(heardList[i]);
cellHead.setCellStyle(style);
}
//设置每格数据的样式 （字体红色）
HSSFCellStyle cellParamStyle = wb.createCellStyle();
HSSFFont ParamFontStyle = wb.createFont();
cellParamStyle.setAlignment(HSSFCellStyle.ALIGN_CENTER);
cellParamStyle.setVerticalAlignment(HSSFCellStyle.VERTICAL_CENTER);
ParamFontStyle.setColor(HSSFColor.DARK_RED.index); //设置字体颜色 (红色)
ParamFontStyle.setFontHeightInPoints((short) this.fontSize);
cellParamStyle.setFont(ParamFontStyle);
//设置每格数据的样式2（字体蓝色）
HSSFCellStyle cellParamStyle2 = wb.createCellStyle();
cellParamStyle2.setAlignment(HSSFCellStyle.ALIGN_CENTER);
cellParamStyle2.setVerticalAlignment(HSSFCellStyle.VERTICAL_CENTER);
HSSFFont ParamFontStyle2 = wb.createFont();
ParamFontStyle2.setColor(HSSFColor.BLUE.index); //设置字体颜色 (蓝色)
ParamFontStyle2.setFontHeightInPoints((short) this.fontSize);
cellParamStyle2.setFont(ParamFontStyle2);
//开始写入实体数据信息
int a = 2;
for (int i = 0; i < data.size(); i++) {
HSSFRow roww = wbSheet.createRow((int) a);
Map map = data.get(i);
HSSFCell cell = null;
for (int j = 0; j < heardKey.length; j++) {
cell = roww.createCell(j);
cell.setCellStyle(style);
Object valueObject = map.get(heardKey[j]);
String value = null;
if (valueObject == null) {
valueObject = "";
}
if (valueObject instanceof String) {
//取出的数据是字符串直接赋值
value = (String) map.get(heardKey[j]);
} else if (valueObject instanceof Integer) {
//取出的数据是Integer
value = String.valueOf(((Integer) (valueObject)).floatValue());
} else if (valueObject instanceof BigDecimal) {
//取出的数据是BigDecimal
value = String.valueOf(((BigDecimal) (valueObject)).floatValue());
} else {
value = valueObject.toString();
}
//设置单个单元格的字体颜色
if(heardKey[j].equals("ddNum") || heardKey[j].equals("sjNum")){
if((Long)map.get("ddNum")!=null){
if((Long)map.get("sjNum")==null){
cell.setCellStyle(cellParamStyle);
} else if((Long) map.get("ddNum") != (Long) map.get("sjNum")){
if ((Long) map.get("ddNum") > (Long) map.get("sjNum")) {
cell.setCellStyle(cellParamStyle);
}
if ((Long) map.get("ddNum") < (Long) map.get("sjNum")) {
cell.setCellStyle(cellParamStyle2);
}
}else {
cell.setCellStyle(style);
}
}
}
cell.setCellValue(Strings.isNullOrEmpty(value) ? "" : value);
}
a++;
}
//导出数据
try {
//设置Http响应头告诉浏览器下载这个附件
response.setHeader("Content-Disposition", "attachment;Filename=" + System.currentTimeMillis() + ".xls");
OutputStream outputStream = response.getOutputStream();
wb.write(outputStream);
outputStream.close();
return wb.getBytes();
} catch (Exception ex) {
ex.printStackTrace();
throw new IOException("导出Excel出现严重异常，异常信息：" + ex.getMessage());
}
}
/**
* 检查数据配置问题
*
* @throws IOException 抛出数据异常类
*/
protected void checkConfig() throws IOException {
if (heardKey == null || heardList.length == 0) {
throw new IOException("列名数组不能为空或者为NULL");
}
if (fontSize < 0 || rowHeight < 0 || columWidth < 0) {
throw new IOException("字体、宽度或者高度不能为负值");
}
if (Strings.isNullOrEmpty(sheetName)) {
throw new IOException("工作表表名不能为NULL");
}
}
}service :
@Override
public void queryProjectInfoBySchemeId(HttpServletResponse response, HttpServletRequest request,
String schemeId, String pushDate) throws IOException {
List<Map> maps = pushMonitorDao.queryProjectInfoBySchemeId(schemeId, pushDate);
if(maps!=null && maps.size()>0){
String companyName = pushMonitorDao.queryCompanyNameBySchemeId(schemeId);
String sheetTitle = companyName;
String [] title = new String[]{"城市","项目名字","合同","实际"}; //设置表格表头字段
String [] properties = new String[]{"city","projectName","ddNum","sjNum"}; // 查询对应的字段
ExcelExportUtil excelExport2 = new ExcelExportUtil();
excelExport2.setData(maps);
excelExport2.setHeardKey(properties);
excelExport2.setFontSize(14);
excelExport2.setSheetName(sheetTitle);
excelExport2.setTitle(sheetTitle);
excelExport2.setHeardList(title);
excelExport2.exportExport(request, response);
}
}Excel格式
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.lang.reflect.Field;
import java.util.List;
import java.util.logging.Level;
import java.util.logging.Logger;
import org.apache.poi.hssf.usermodel.HSSFCell;
import org.apache.poi.hssf.usermodel.HSSFCellStyle;
import org.apache.poi.hssf.usermodel.HSSFFont;
import org.apache.poi.hssf.usermodel.HSSFRow;
import org.apache.poi.hssf.usermodel.HSSFSheet;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.ss.usermodel.VerticalAlignment;
import org.apache.poi.ss.util.CellRangeAddress;
/**
* @作者 yan
* @创建日期
* @版本 V1.0
* @描述 Excel 导出通用工具类
*/
public class ExcelUtil {
public static byte[] export(String sheetTitle, String[] title, List<Object> list) {
HSSFWorkbook wb = new HSSFWorkbook();//创建excel表
HSSFSheet sheet = wb.createSheet(sheetTitle);
sheet.setDefaultColumnWidth(20);//设置默认行宽
//表头样式（加粗，水平居中，垂直居中）
HSSFCellStyle cellStyle = wb.createCellStyle();
cellStyle.setAlignment(HSSFCellStyle.ALIGN_CENTER);//水平居中
cellStyle.setVerticalAlignment(VerticalAlignment.CENTER);//垂直居中
//设置边框样式
cellStyle.setBorderBottom(HSSFCellStyle.BORDER_THIN); //下边框
cellStyle.setBorderLeft(HSSFCellStyle.BORDER_THIN);//左边框
cellStyle.setBorderTop(HSSFCellStyle.BORDER_THIN);//上边框
cellStyle.setBorderRight(HSSFCellStyle.BORDER_THIN);//右边框
HSSFFont fontStyle = wb.createFont();
fontStyle.setBoldweight(HSSFFont.BOLDWEIGHT_BOLD);
cellStyle.setFont(fontStyle);
//标题样式（加粗，垂直居中）
HSSFCellStyle cellStyle2 = wb.createCellStyle();
cellStyle2.setVerticalAlignment(VerticalAlignment.CENTER);//垂直居中
cellStyle2.setFont(fontStyle);
//设置边框样式
cellStyle2.setBorderBottom(HSSFCellStyle.BORDER_THIN); //下边框
cellStyle2.setBorderLeft(HSSFCellStyle.BORDER_THIN);//左边框
cellStyle2.setBorderTop(HSSFCellStyle.BORDER_THIN);//上边框
cellStyle2.setBorderRight(HSSFCellStyle.BORDER_THIN);//右边框
//字段样式（垂直居中）
HSSFCellStyle cellStyle3 = wb.createCellStyle();
cellStyle3.setVerticalAlignment(VerticalAlignment.CENTER);//垂直居中
//设置边框样式
cellStyle3.setBorderBottom(HSSFCellStyle.BORDER_THIN); //下边框
cellStyle3.setBorderLeft(HSSFCellStyle.BORDER_THIN);//左边框
cellStyle3.setBorderTop(HSSFCellStyle.BORDER_THIN);//上边框
cellStyle3.setBorderRight(HSSFCellStyle.BORDER_THIN);//右边框
//创建表头
HSSFRow row = sheet.createRow(0);
row.setHeightInPoints(20);//行高
HSSFCell cell = row.createCell(0);
cell.setCellValue(sheetTitle);
cell.setCellStyle(cellStyle);
sheet.addMergedRegion(new CellRangeAddress(0,0,0,(title.length-1)));
//创建标题
HSSFRow rowTitle = sheet.createRow(1);
rowTitle.setHeightInPoints(20);
HSSFCell hc;
for (int i = 0; i < title.length; i++) {
hc = rowTitle.createCell(i);
hc.setCellValue(title[i]);
hc.setCellStyle(cellStyle2);
}
byte result[] = null;
ByteArrayOutputStream out = null;
try {
//创建表格数据
Field[] fields;
int i = 2;
for (Object obj : list) {
fields = obj.getClass().getDeclaredFields();
HSSFRow rowBody = sheet.createRow(i);
rowBody.setHeightInPoints(20);
int j = 0;
for (Field f : fields) {
f.setAccessible(true);
Object va = f.get(obj);
if (null == va) {
va = "";
}
hc = rowBody.createCell(j);
hc.setCellValue(va.toString());
hc.setCellStyle(cellStyle3);
j++;
}
i++;
}
out = new ByteArrayOutputStream();
wb.write(out);
result = out.toByteArray();
} catch (Exception ex) {
Logger.getLogger(ExcelUtil.class.getName()).log(Level.SEVERE, null, ex);
} finally{
try {
if(null != out){
out.close();
}
} catch (IOException ex) {
Logger.getLogger(ExcelUtil.class.getName()).log(Level.SEVERE, null, ex);
} finally{
try {
wb.close();
} catch (IOException ex) {
Logger.getLogger(ExcelUtil.class.getName()).log(Level.SEVERE, null, ex);
}
}
}
return result;
}
}更多java知识请关注java基础教程栏目。
代码注释
[!--zhushi--]
