Apache POI 官方文档解析和趣谈

yywx001

　　我希望看到这篇文章大家不要转载
　　在这里我想说明一下，我接触POI也是不太时间，有句话大家都会说，“如果有什么不对的地方，希望大家包涵”，哈哈
　　我这里也引用一下，如果有错误的地方，希望大家指出来，我非常高兴
　　我这篇文章不想长篇大论的讲POI是什么，题目为趣谈，那么当然是开开心心的学习一门新技术，哈哈，好吧，废话就不说了，现在开始

Apache POI - the Java API for Microsoft Documents
　　官方的大题目，哇，好大，哈哈，很明显POI是什么 就是java API ，什么API，是为了解析微软文档文件的，哈哈我说了一堆废话，哈哈，简直就是在翻译吗。。。翻译也罢，反正POI就是这个意思
　　官网大篇幅的讲述POI是做什么的，这里我不想当interpreter，所以这里就不翻译了，我建议大家读读，为了更加了解POI，这里我提供链接
　　官网： http://poi.apache.org/index.html
　　至于下载吗，哈哈，我想做技术的，不用我叫怎么下载吧，你们懂的
　　既然POI是解析MD(Microsoft Document)，那么我们对MD分别分析
　　Excel 
　　我把官网给的图图做了处理，让大家看的更加清晰：

 

上面的图已经很清晰的说明Excel2003和Excel2003的基本区别和相同点，POI对Excel2010其实和2007出不多，但有的时候会出现bug。我没有做尝试，这里暂不说明

 

基本操作：

 

1.创建Excel文件

 

 

Workbook wb = new HSSFWorkbook();
FileOutputStream fileOut = new FileOutputStream("excel.xls");
wb.write(fileOut);
fileOut.close();

Workbook wb = new XSSFWorkbook();
FileOutputStream fileOut = new FileOutputStream("excel.xlsx");
wb.write(fileOut);
fileOut.close();

 

noite： 第一HSSF只能创建后缀名为.xls文件，XSSF只能创建xlsx文件 互换的，生成的excel打不开

 

2.创建sheet

 

 

   Workbook wb = new HSSFWorkbook();  // or new XSSFWorkbook();
Sheet sheet1 = wb.createSheet("new sheet");
Sheet sheet2 = wb.createSheet("second sheet");
// Note that sheet name is Excel must not exceed 31 characters
// and must not contain any of the any of the following characters:
// 0x0000
// 0x0003
// colon (:)
// backslash (\)
// asterisk (*)
// question mark (?)
// forward slash (/)
// opening square bracket ([)
// closing square bracket (])
// You can use org.apache.poi.ss.util.WorkbookUtil#createSafeSheetName(String nameProposal)}
// for a safe way to create valid names, this utility replaces invalid characters with a space (' ')
String safeName = WorkbookUtil.createSafeSheetName("[O'Brien's sales*?]"); // returns " O'Brien's sales   "
Sheet sheet3 = wb.createSheet(safeName);
FileOutputStream fileOut = new FileOutputStream("workbook.xls");
wb.write(fileOut);
fileOut.close();
 

这是官网给力例子，我这里直接写出，嘿嘿，趣谈来了，要注意哦名字就有限制的，所以最好用createSafeSheetName

 

3.创建cell

 

 

Workbook wb = new HSSFWorkbook();
//Workbook wb = new XSSFWorkbook();
CreationHelper createHelper = wb.getCreationHelper();
Sheet sheet = wb.createSheet("new sheet");
// Create a row and put some cells in it. Rows are 0 based.
Row row = sheet.createRow((short)0);
// Create a cell and put a value in it.
Cell cell = row.createCell(0);
cell.setCellValue(1);
// Or do it on one line.
row.createCell(1).setCellValue(1.2);
row.createCell(2).setCellValue(
createHelper.createRichTextString("This is a string"));
row.createCell(3).setCellValue(true);
// Write the output to a file
FileOutputStream fileOut = new FileOutputStream("workbook.xls");
wb.write(fileOut);
fileOut.close();

 

官网给的小例子真是刚猛，太经典了

 

4.创建时间类型的cell

 

 

Workbook wb = new HSSFWorkbook();
//Workbook wb = new XSSFWorkbook();
CreationHelper createHelper = wb.getCreationHelper();
Sheet sheet = wb.createSheet("new sheet");
// Create a row and put some cells in it. Rows are 0 based.
Row row = sheet.createRow(0);
// Create a cell and put a date value in it.  The first cell is not styled
// as a date.
Cell cell = row.createCell(0);
cell.setCellValue(new Date());
// we style the second cell as a date (and time).  It is important to
// create a new cell style from the workbook otherwise you can end up
// modifying the built in style and effecting not only this cell but other cells.
CellStyle cellStyle = wb.createCellStyle();
cellStyle.setDataFormat(
createHelper.createDataFormat().getFormat("m/d/yy h:mm"));
cell = row.createCell(1);
cell.setCellValue(new Date());
cell.setCellStyle(cellStyle);
//you can also set date as java.util.Calendar
cell = row.createCell(2);
cell.setCellValue(Calendar.getInstance());
cell.setCellStyle(cellStyle);
// Write the output to a file
FileOutputStream fileOut = new FileOutputStream("workbook.xls");
wb.write(fileOut);
fileOut.close();
 

这里要注意cellStyle的运用，它可是POI的小画家啊，特别爱涂色

 

5.创建不同的行的cell

 

Workbook wb = new HSSFWorkbook();
Sheet sheet = wb.createSheet("new sheet");
Row row = sheet.createRow((short)2);
row.createCell(0).setCellValue(1.1);
row.createCell(1).setCellValue(new Date());
row.createCell(2).setCellValue(Calendar.getInstance());
row.createCell(3).setCellValue("a string");
row.createCell(4).setCellValue(true);
row.createCell(5).setCellType(Cell.CELL_TYPE_ERROR);
// Write the output to a file
FileOutputStream fileOut = new FileOutputStream("workbook.xls");
wb.write(fileOut);
fileOut.close();
 

6.设定单元格内的相对位置

 

 

public static void main(String[] args)  throws Exception {
Workbook wb = new XSSFWorkbook(); //or new HSSFWorkbook();
Sheet sheet = wb.createSheet();
Row row = sheet.createRow((short) 2);
row.setHeightInPoints(30);
createCell(wb, row, (short) 0, CellStyle.ALIGN_CENTER, CellStyle.VERTICAL_BOTTOM);
createCell(wb, row, (short) 1, CellStyle.ALIGN_CENTER_SELECTION, CellStyle.VERTICAL_BOTTOM);
createCell(wb, row, (short) 2, CellStyle.ALIGN_FILL, CellStyle.VERTICAL_CENTER);
createCell(wb, row, (short) 3, CellStyle.ALIGN_GENERAL, CellStyle.VERTICAL_CENTER);
createCell(wb, row, (short) 4, CellStyle.ALIGN_JUSTIFY, CellStyle.VERTICAL_JUSTIFY);
createCell(wb, row, (short) 5, CellStyle.ALIGN_LEFT, CellStyle.VERTICAL_TOP);
createCell(wb, row, (short) 6, CellStyle.ALIGN_RIGHT, CellStyle.VERTICAL_TOP);
// Write the output to a file
FileOutputStream fileOut = new FileOutputStream("xssf-align.xlsx");
wb.write(fileOut);
fileOut.close();
}
/**
* Creates a cell and aligns it a certain way.
*
* @param wb     the workbook
* @param row    the row to create the cell in
* @param column the column number to create the cell in
* @param halign the horizontal alignment for the cell.
*/
private static void createCell(Workbook wb, Row row, short column, short halign, short valign) {
Cell cell = row.createCell(column);
cell.setCellValue("Align It");
CellStyle cellStyle = wb.createCellStyle();
cellStyle.setAlignment(halign);
cellStyle.setVerticalAlignment(valign);
cell.setCellStyle(cellStyle);
}

 

这个很少用到，很少有人在单元格内设定位置。。。

 

7.给单元格加边框

 

 

Workbook wb = new HSSFWorkbook();
Sheet sheet = wb.createSheet("new sheet");
// Create a row and put some cells in it. Rows are 0 based.
Row row = sheet.createRow(1);
// Create a cell and put a value in it.
Cell cell = row.createCell(1);
cell.setCellValue(4);
// Style the cell with borders all around.
CellStyle style = wb.createCellStyle();
style.setBorderBottom(CellStyle.BORDER_THIN);
style.setBottomBorderColor(IndexedColors.BLACK.getIndex());
style.setBorderLeft(CellStyle.BORDER_THIN);
style.setLeftBorderColor(IndexedColors.GREEN.getIndex());
style.setBorderRight(CellStyle.BORDER_THIN);
style.setRightBorderColor(IndexedColors.BLUE.getIndex());
style.setBorderTop(CellStyle.BORDER_MEDIUM_DASHED);
style.setTopBorderColor(IndexedColors.BLACK.getIndex());
cell.setCellStyle(style);
// Write the output to a file
FileOutputStream fileOut = new FileOutputStream("workbook.xls");
wb.write(fileOut);
fileOut.close();

 8.遍历每个单元格

 

 

sheet sheet = wb.getsheetat(0);
for (iterator<row> rit = sheet.rowiterator(); rit.hasnext(); ) {
row row = rit.next();
for (iterator<cell> cit = row.celliterator(); cit.hasnext(); ) {
cell cell = cit.next();
// do something here
}
}

 

 

 

Sheet sheet = wb.getSheetAt(0);
for (Row row : sheet) {
for (Cell cell : row) {
// Do something here
}
}

 

9.填涂单元格颜色

 

 

Workbook wb = new XSSFWorkbook();
Sheet sheet = wb.createSheet("new sheet");
// Create a row and put some cells in it. Rows are 0 based.
Row row = sheet.createRow((short) 1);
// Aqua background
CellStyle style = wb.createCellStyle();
style.setFillBackgroundColor(IndexedColors.AQUA.getIndex());
style.setFillPattern(CellStyle.BIG_SPOTS);
Cell cell = row.createCell((short) 1);
cell.setCellValue("X");
cell.setCellStyle(style);
// Orange "foreground", foreground being the fill foreground not the font color.
style = wb.createCellStyle();
style.setFillForegroundColor(IndexedColors.ORANGE.getIndex());
style.setFillPattern(CellStyle.SOLID_FOREGROUND);
cell = row.createCell((short) 2);
cell.setCellValue("X");
cell.setCellStyle(style);
// Write the output to a file
FileOutputStream fileOut = new FileOutputStream("workbook.xls");
wb.write(fileOut);
fileOut.close();
 

10.合并单元格

 

Workbook wb = new HSSFWorkbook();
Sheet sheet = wb.createSheet("new sheet");
Row row = sheet.createRow((short) 1);
Cell cell = row.createCell((short) 1);
cell.setCellValue("This is a test of merging");
sheet.addMergedRegion(new CellRangeAddress(
1, //first row (0-based)
1, //last row  (0-based)
1, //first column (0-based)
2  //last column  (0-based)
));
// Write the output to a file
FileOutputStream fileOut = new FileOutputStream("workbook.xls");
wb.write(fileOut);
fileOut.close();
 

11.改变文字

 

 

Workbook wb = new HSSFWorkbook();
Sheet sheet = wb.createSheet("new sheet");
// Create a row and put some cells in it. Rows are 0 based.
Row row = sheet.createRow(1);
// Create a new font and alter it.
Font font = wb.createFont();
font.setFontHeightInPoints((short)24);
font.setFontName("Courier New");
font.setItalic(true);
font.setStrikeout(true);
// Fonts are set into a style so create a new one to use.
CellStyle style = wb.createCellStyle();
style.setFont(font);
// Create a cell and put a value in it.
Cell cell = row.createCell(1);
cell.setCellValue("This is a test of fonts");
cell.setCellStyle(style);
// Write the output to a file
FileOutputStream fileOut = new FileOutputStream("workbook.xls");
wb.write(fileOut);
fileOut.close();

 12.读excel文件

 

 

InputStream inp = new FileInputStream("workbook.xls");
//InputStream inp = new FileInputStream("workbook.xlsx");
Workbook wb = WorkbookFactory.create(inp);
Sheet sheet = wb.getSheetAt(0);
Row row = sheet.getRow(2);
Cell cell = row.getCell(3);
if (cell == null)
cell = row.createCell(3);
cell.setCellType(Cell.CELL_TYPE_STRING);
cell.setCellValue("a test");
// Write the output to a file
FileOutputStream fileOut = new FileOutputStream("workbook.xls");
wb.write(fileOut);
fileOut.close();

 13.添加新行

 

 

Workbook wb = new XSSFWorkbook();   //or new HSSFWorkbook();
Sheet sheet = wb.createSheet();
Row row = sheet.createRow(2);
Cell cell = row.createCell(2);
cell.setCellValue("Use \n with word wrap on to create a new line");
//to enable newlines you need set a cell styles with wrap=true
CellStyle cs = wb.createCellStyle();
cs.setWrapText(true);
cell.setCellStyle(cs);
//increase row height to accomodate two lines of text
row.setHeightInPoints((2*sheet.getDefaultRowHeightInPoints()));
//adjust column width to fit the content
sheet.autoSizeColumn((short)2);
FileOutputStream fileOut = new FileOutputStream("ooxml-newlines.xlsx");
wb.write(fileOut);
fileOut.close();

 以上是基本的常用的操作，我也给出代码出处：

 

http://poi.apache.org/spreadsheet/quick-guide.html#NewWorkbook