POI導出EXCEL經典實作
在web開發中，有一個經典的功能，就是資料的導入導出。特别是資料的導出，在生産管理或者财務系統中用的非常普遍，因為這些系統經常要做一些報表列印的工作。而資料導出的格式一般是EXCEL或者PDF，我這裡就用兩篇文章分别給大家介紹下。(注意，我們這裡說的資料導出可不是資料庫中的資料導出！麼誤會啦^_^)
呵呵，首先我們來導出EXCEL格式的檔案吧。現在主流的操作Excel檔案的開源工具有很多,用得比較多的就是Apache的POI及JExcelAPI。這裡我們用Apache POI！我們先去Apache的大學營下載下傳POI的jar包：http://poi.apache.org/ ，我這裡使用的是3.0.2版本。
将3個jar包導入到classpath下，什麼？忘了怎麼導包？不會吧！好，我們來寫一個導出Excel的實用類(所謂實用，是指基本不用怎麼修改就可以在實際項目中直接使用的！)。我一直強調做類也好，做方法也好，一定要通用性和靈活性強。下面這個類就算基本貫徹了我的這種思想。那麼，熟悉許老師風格的人應該知道，這時候該要甩出一長串代碼了。沒錯，大夥請看：
package org.leno.export.util;
import java.util.Date;
public class Student {
private long id;
private String name;
private int age;
private boolean sex;
private Date birthday;
public Student() {
super();
// TODO Auto-generated constructor stub
}
public Student(long id, String name, int age, boolean sex, Date birthday) {
super();
this.id = id;
this.name = name;
this.age = age;
this.sex = sex;
this.birthday = birthday;
}
public long getId() {
return id;
}
public void setId(long id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
public boolean getSex() {
return sex;
}
public void setSex(boolean sex) {
this.sex = sex;
}
public Date getBirthday() {
return birthday;
}
public void setBirthday(Date birthday) {
this.birthday = birthday;
}
}
package org.leno.export.util;
public class Book {
private int bookId;
private String name;
private String author;
private float price;
private String isbn;
private String pubName;
private byte[] preface;
public Book() {
super();
}
public Book(int bookId, String name, String author, float price,
String isbn, String pubName, byte[] preface) {
super();
this.bookId = bookId;
this.name = name;
this.author = author;
this.price = price;
this.isbn = isbn;
this.pubName = pubName;
this.preface = preface;
}
public int getBookId() {
return bookId;
}
public void setBookId(int bookId) {
this.bookId = bookId;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getAuthor() {
return author;
}
public void setAuthor(String author) {
this.author = author;
}
public float getPrice() {
return price;
}
public void setPrice(float price) {
this.price = price;
}
public String getIsbn() {
return isbn;
}
public void setIsbn(String isbn) {
this.isbn = isbn;
}
public String getPubName() {
return pubName;
}
public void setPubName(String pubName) {
this.pubName = pubName;
}
public byte[] getPreface() {
return preface;
}
public void setPreface(byte[] preface) {
this.preface = preface;
}
}
上面這兩個類一目了然，就是兩個簡單的javabean風格的類。再看下面真正的重點類：
package org.leno.export.util;
import java.io.*;
import java.lang.reflect.*;
import java.util.*;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import java.text.SimpleDateFormat;
import javax.swing.JOptionPane;
import org.apache.poi.hssf.usermodel.*;
import org.apache.poi.hssf.util.HSSFColor;
public class ExportExcel {
public void exportExcel(Collection dataset, OutputStream out) {
exportExcel("測試POI導出EXCEL文檔", null, dataset, out, "yyyy-MM-dd");
}
public void exportExcel(String[] headers, Collection dataset,
OutputStream out) {
exportExcel("測試POI導出EXCEL文檔", headers, dataset, out, "yyyy-MM-dd");
}
public void exportExcel(String[] headers, Collection dataset,
OutputStream out, String pattern) {
exportExcel("測試POI導出EXCEL文檔", headers, dataset, out, pattern);
}
@SuppressWarnings("unchecked")
public void exportExcel(String title, String[] headers,
Collection dataset, OutputStream out, String pattern) {
// 聲明一個工作薄
HSSFWorkbook workbook = new HSSFWorkbook();
// 生成一個表格
HSSFSheet sheet = workbook.createSheet(title);
// 設定表格預設列寬度為15個位元組
sheet.setDefaultColumnWidth((short) 15);
// 生成一個樣式
HSSFCellStyle style = workbook.createCellStyle();
// 設定這些樣式
style.setFillForegroundColor(HSSFColor.SKY_BLUE.index);
style.setFillPattern(HSSFCellStyle.SOLID_FOREGROUND);
style.setBorderBottom(HSSFCellStyle.BORDER_THIN);
style.setBorderLeft(HSSFCellStyle.BORDER_THIN);
style.setBorderRight(HSSFCellStyle.BORDER_THIN);
style.setBorderTop(HSSFCellStyle.BORDER_THIN);
style.setAlignment(HSSFCellStyle.ALIGN_CENTER);
// 生成一個字型
HSSFFont font = workbook.createFont();
font.setColor(HSSFColor.VIOLET.index);
font.setFontHeightInPoints((short) 12);
font.setBoldweight(HSSFFont.BOLDWEIGHT_BOLD);
// 把字型應用到目前的樣式
style.setFont(font);
// 生成并設定另一個樣式
HSSFCellStyle style2 = workbook.createCellStyle();
style2.setFillForegroundColor(HSSFColor.LIGHT_YELLOW.index);
style2.setFillPattern(HSSFCellStyle.SOLID_FOREGROUND);
style2.setBorderBottom(HSSFCellStyle.BORDER_THIN);
style2.setBorderLeft(HSSFCellStyle.BORDER_THIN);
style2.setBorderRight(HSSFCellStyle.BORDER_THIN);
style2.setBorderTop(HSSFCellStyle.BORDER_THIN);
style2.setAlignment(HSSFCellStyle.ALIGN_CENTER);
style2.setVerticalAlignment(HSSFCellStyle.VERTICAL_CENTER);
// 生成另一個字型
HSSFFont font2 = workbook.createFont();
font2.setBoldweight(HSSFFont.BOLDWEIGHT_NORMAL);
// 把字型應用到目前的樣式
style2.setFont(font2);
// 聲明一個畫圖的頂級管理器
HSSFPatriarch patriarch = sheet.createDrawingPatriarch();
// 定義注釋的大小和位置,詳見文檔
HSSFComment comment = patriarch.createComment(new HSSFClientAnchor(0, 0, 0, 0, (short) 4, 2, (short) 6, 5));
// 設定注釋内容
comment.setString(new HSSFRichTextString("可以在POI中添加注釋！"));
// 設定注釋作者，當滑鼠移動到單元格上是可以在狀态欄中看到該内容.
comment.setAuthor("leno");
//産生表格标題行
HSSFRow row = sheet.createRow(0);
for (short i = 0; i < headers.length; i++) {
HSSFCell cell = row.createCell(i);
cell.setCellStyle(style);
HSSFRichTextString text = new HSSFRichTextString(headers[i]);
cell.setCellValue(text);
}
//周遊集合資料，産生資料行
Iterator it = dataset.iterator();
int index = 0;
while (it.hasNext()) {
index++;
row = sheet.createRow(index);
T t = (T) it.next();
//利用反射，根據javabean屬性的先後順序，動态調用getXxx()方法得到屬性值
Field[] fields = t.getClass().getDeclaredFields();
for (short i = 0; i < fields.length; i++) {
HSSFCell cell = row.createCell(i);
cell.setCellStyle(style2);
Field field = fields[i];
String fieldName = field.getName();
String getMethodName = "get"
+ fieldName.substring(0, 1).toUpperCase()
+ fieldName.substring(1);
try {
Class tCls = t.getClass();
Method getMethod = tCls.getMethod(getMethodName,
new Class[] {});
Object value = getMethod.invoke(t, new Object[] {});
//判斷值的類型後進行強制類型轉換
String textValue = null;
// if (value instanceof Integer) {
// int intValue = (Integer) value;
// cell.setCellValue(intValue);
// } else if (value instanceof Float) {
// float fValue = (Float) value;
// textValue = new HSSFRichTextString(
// String.valueOf(fValue));
// cell.setCellValue(textValue);
// } else if (value instanceof Double) {
// double dValue = (Double) value;
// textValue = new HSSFRichTextString(
// String.valueOf(dValue));
// cell.setCellValue(textValue);
// } else if (value instanceof Long) {
// long longValue = (Long) value;
// cell.setCellValue(longValue);
// }
if (value instanceof Boolean) {
boolean bValue = (Boolean) value;
textValue = "男";
if (!bValue) {
textValue ="女";
}
} else if (value instanceof Date) {
Date date = (Date) value;
SimpleDateFormat sdf = new SimpleDateFormat(pattern);
textValue = sdf.format(date);
} else if (value instanceof byte[]) {
// 有圖檔時，設定行高為60px;
row.setHeightInPoints(60);
// 設定圖檔所在列寬度為80px,注意這裡機關的一個換算
sheet.setColumnWidth(i, (short) (35.7 * 80));
// sheet.autoSizeColumn(i);
byte[] bsValue = (byte[]) value;
HSSFClientAnchor anchor = new HSSFClientAnchor(0, 0,
1023, 255, (short) 6, index, (short) 6, index);
anchor.setAnchorType(2);
patriarch.createPicture(anchor, workbook.addPicture(
bsValue, HSSFWorkbook.PICTURE_TYPE_JPEG));
} else{
//其它資料類型都當作字元串簡單處理
textValue = value.toString();
}
//如果不是圖檔資料，就利用正規表達式判斷textValue是否全部由數字組成
if(textValue!=null){
Pattern p = Pattern.compile("^""d+("".""d+)?$");
Matcher matcher = p.matcher(textValue);
if(matcher.matches()){
//是數字當作double處理
cell.setCellValue(Double.parseDouble(textValue));
}else{
HSSFRichTextString richString = new HSSFRichTextString(textValue);
HSSFFont font3 = workbook.createFont();
font3.setColor(HSSFColor.BLUE.index);
richString.applyFont(font3);
cell.setCellValue(richString);
}
}
} catch (SecurityException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (NoSuchMethodException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IllegalArgumentException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IllegalAccessException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (InvocationTargetException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} finally {
//清理資源
}
}
}
try {
workbook.write(out);
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public static void main(String[] args) {
// 測試學生
ExportExcel ex = new ExportExcel();
String[] headers = { "學号", "姓名", "年齡", "性别", "出生日期" };
List dataset = new ArrayList();
dataset.add(new Student(10000001, "張三", 20, true, new Date()));
dataset.add(new Student(20000002, "李四", 24, false, new Date()));
dataset.add(new Student(30000003, "王五", 22, true, new Date()));
// 測試圖書
ExportExcel ex2 = new ExportExcel();
String[] headers2 = { "圖書編号", "圖書名稱", "圖書作者", "圖書價格", "圖書ISBN",
"圖書出版社", "封面圖檔" };
List dataset2 = new ArrayList();
try {
BufferedInputStream bis = new BufferedInputStream(
new FileInputStream("book.jpg"));
byte[] buf = new byte[bis.available()];
while ((bis.read(buf)) != -1) {
//
}
dataset2.add(new Book(1, "jsp", "leno", 300.33f, "1234567",
"清華出版社", buf));
dataset2.add(new Book(2, "java程式設計思想", "brucl", 300.33f, "1234567",
"陽光出版社", buf));
dataset2.add(new Book(3, "DOM藝術", "lenotang", 300.33f, "1234567",
"清華出版社", buf));
dataset2.add(new Book(4, "c++經典", "leno", 400.33f, "1234567",
"清華出版社", buf));
dataset2.add(new Book(5, "c#入門", "leno", 300.33f, "1234567",
"湯春秀出版社", buf));
OutputStream out = new FileOutputStream("E:""a.xls");
OutputStream out2 = new FileOutputStream("E:""b.xls");
ex.exportExcel(headers, dataset, out);
ex2.exportExcel(headers2, dataset2, out2);
out.close();
JOptionPane.showMessageDialog(null, "導出成功!");
System.out.println("excel導出成功！");
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
不行，頭有點暈^_^。呵呵，又是泛型，又是反射，又是正規表達式，又是重載,還有多參數清單和POI API。一下子蹦出來，實在讓人吃不消。不管了，頂住看效果先。在本地運作後，我們發現在E:""下生成了兩份excel檔案：學生記錄和圖書記錄，并且中文，數字，顔色，日期，圖檔等等一且正常。恩，太棒了。有人看到這裡開始苦臉了：喂，我怎麼一運作就報錯啊！呵呵，看看什麼錯吧！哦，找不到檔案，也就是說你沒有book.jpg嘛。好，拷貝一張小巧的圖書圖檔命名為book.jpg放置到目前工程下吧。注意，您千萬别把張桌面大小的圖檔丢進去了^_^！看到效果了吧。現在我們再來簡單梳理一下代碼，實際上上面就做了一個導出excel的方法和一個本地測試main()方法。并且代碼的結構也很清晰，隻是涉及的知識點稍微多一點。大家細心看看注釋，結合要完成的功能，應該沒有太大問題的。好啦，吃杯茶，擦把汗，總算把這個類消化掉，你又進步了。咦，你不是說是在WEB環境下導出的嗎？别急，因為導出就是一個下載下傳的過程。我們隻需要在伺服器端寫一個Jsp或者Servlet元件完成輸出excel到浏覽器用戶端的工作就好了。我們以Servlet為例，還是看代碼吧：
package org.leno.export.util;
import java.io.*;
import java.util.ArrayList;
import java.util.List;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class Export extends javax.servlet.http.HttpServlet{
static final long serialVersionUID = 1L;
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
File file = new File(getServletContext().getRealPath("WEB-INF/book.jpg"));
response.setContentType("octets/stream");
response.addHeader("Content-Disposition", "attachment;filename=test.xls");
//測試圖書
ExportExcel ex = new ExportExcel();
String[] headers = { "圖書編号", "圖書名稱", "圖書作者", "圖書價格", "圖書ISBN",
"圖書出版社", "封面圖檔" };
List dataset = new ArrayList();
try {
BufferedInputStream bis = new BufferedInputStream(
new FileInputStream(file));
byte[] buf = new byte[bis.available()];
while ((bis.read(buf)) != -1) {
//将圖檔資料存放到緩沖數組中
}
dataset.add(new Book(1, "jsp", "leno", 300.33f, "1234567",
"清華出版社", buf));
dataset.add(new Book(2, "java程式設計思想", "brucl", 300.33f, "1234567",
"陽光出版社", buf));
dataset.add(new Book(3, "DOM藝術", "lenotang", 300.33f, "1234567",
"清華出版社", buf));
dataset.add(new Book(4, "c++經典", "leno", 400.33f, "1234567",
"清華出版社", buf));
dataset.add(new Book(5, "c#入門", "leno", 300.33f, "1234567",
"湯春秀出版社", buf));
OutputStream out = response.getOutputStream();
ex.exportExcel(headers, dataset, out);
out.close();
System.out.println("excel導出成功！");
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
doGet(request, response);
}
}
寫完之後，如果您不是用eclipse工具生成的Servlet,千萬别忘了在web.xml上注冊這個Servelt。而且同樣的，拷貝一張小巧的圖書圖檔命名為book.jpg放置到目前WEB根目錄的/WEB-INF/下。部署好web工程，用浏覽器通路Servlet看下效果吧！是不是下載下傳成功了。呵呵，您可以将下載下傳到本地的excel報表用列印機列印出來，這樣您就大功告成了。完事了我們就思考：我們發現，我們做的方法，不管是本地調用，還是在WEB伺服器端用Servlet調用；不管是輸出學生清單，還是圖書清單資訊，代碼都幾乎一樣，而且這些資料我們很容器結合背景的DAO操作資料庫動态擷取。恩，類和方法的通用性和靈活性開始有點感覺了。好啦，祝您學習愉快！
本文來自CSDN部落格，轉載請标明出處：http://blog.csdn.net/lenotang/archive/2008/08/24/2823230.aspx
posted on 2010-11-24 09:32 David1228 閱讀(967) 評論(0) 編輯 收藏