excel有四个主要对象:工作薄、工作表、行、单元格
1.POI的写操作
创建一个maven项目,需要引入POI的一些包
<!--xls(03)-->
<dependency>
<groupId>org.apache.poi</groupId>
<artifactId>poi</artifactId>
<version>3.9</version>
</dependency>
<!--xls(07)-->
<dependency>
<groupId>org.apache.poi</groupId>
<artifactId>poi-ooxml</artifactId>
<version>3.9</version>
</dependency>
写操作基本包括如下步骤(针对03年Excel):
- 创建工作薄
//创建一个工作簿
Workbook workbook = new HSSFWorkbook();
- 创建工作表
//创建一个工作表
Sheet sheet = workbook.createSheet("学生统计表");
- 创建行
//创建一个行
Row row1 = sheet.createRow(0);
- 创建单元格,并赋值
//创建一个单元格
Cell cell = row1.createCell(0);
cell.setCellValue("1,1");
- 生成表
//生成一张表
FileOutputStream fileOutputStream = new FileOutputStream(path+"学生统计表.xls");
workbook.write(fileOutputStream);
//关闭
fileOutputStream.close();
07版和03版操作一样,就是工作簿对象不一样,同时也是文件后缀不一样
@Test
//针对07版Excel
public void test07() throws Exception {
//创建一个工作簿
Workbook workbook = new XSSFWorkbook();
//创建一个工作表
Sheet sheet = workbook.createSheet("学生统计表");
//创建一个行
Row row1 = sheet.createRow(0);
//创建一个单元格
Cell cell = row1.createCell(0);
cell.setCellValue("1,1");
//生成一张表
FileOutputStream fileOutputStream = new FileOutputStream(path+"学生统计表.xlsx");
workbook.write(fileOutputStream);
//关闭
fileOutputStream.close();
}
2. POI大数据量写入
03版:只能导65536行数据
@Test
//针对03版Excel
public void test03BigData() throws Exception {
long begin = System.currentTimeMillis();
//创建一个工作簿
Workbook workbook = new HSSFWorkbook();
//创建一个工作表
Sheet sheet = workbook.createSheet("学生统计表");
//大数据导入
for(int rowNum=0;rowNum<65536;rowNum++) {
Row row = sheet.createRow(rowNum);
for (int column = 0; column < 10; column++) {
Cell cell = row.createCell(column);
cell.setCellValue(column);
}
}
//生成一张表
FileOutputStream fileOutputStream = new FileOutputStream(path+"学生统计表.xls");
workbook.write(fileOutputStream);
//关闭
fileOutputStream.close();
long end = System.currentTimeMillis();
System.out.println("时间"+(end-begin)/1000+"s");
}
07版:无行数限制速度慢
@Test
//针对03版Excel
public void test07BigData() throws Exception {
long begin = System.currentTimeMillis();
//创建一个工作簿
Workbook workbook = new XSSFWorkbook();
//创建一个工作表
Sheet sheet = workbook.createSheet("学生统计表");
//大数据导入
for(int rowNum=0;rowNum<65536;rowNum++) {
Row row = sheet.createRow(rowNum);
for (int column = 0; column < 10; column++) {
Cell cell = row.createCell(column);
cell.setCellValue(column);
}
}
//生成一张表
FileOutputStream fileOutputStream = new FileOutputStream(path+"学生统计表.xlsx");
workbook.write(fileOutputStream);
//关闭
fileOutputStream.close();
long end = System.currentTimeMillis();
System.out.println("时间"+(end-begin)/1000+"s");
}
加速版:
@Test
//针对07版Excel
public void test07BigDataS() throws Exception {
long begin = System.currentTimeMillis();
//创建一个工作簿
Workbook workbook = new SXSSFWorkbook();
//创建一个工作表
Sheet sheet = workbook.createSheet("学生统计表");
//大数据导入
for(int rowNum=0;rowNum<100000;rowNum++) {
Row row = sheet.createRow(rowNum);
for (int column = 0; column < 10; column++) {
Cell cell = row.createCell(column);
cell.setCellValue(column);
}
}
//生成一张表
FileOutputStream fileOutputStream = new FileOutputStream(path+"学生统计表.xlsx");
workbook.write(fileOutputStream);
//关闭
fileOutputStream.close();
//清除临时文件
((SXSSFWorkbook)workbook).dispose();
long end = System.currentTimeMillis();
System.out.println("时间"+(end-begin)/1000+"s");
}
3. poi读操作
步骤:
- 获取文件流
FileInputStream fileInputStream = new FileInputStream(path + "学生统计表.xlsx");
- 根据文件流创建工作薄
//创建工作薄
Workbook workbook = new HSSFWorkbook(fileInputStream);
- 得到工作表
//获得工作表
Sheet sheet = workbook.getSheetAt(0);
- 得到行
//获得行
Row row = sheet.getRow(0);
- 得到单元格并输出,读取值要保证类型相同
//获得单元格
Cell cell = row.getCell(0);
System.out.println(cell.getStringCellValue());
- 关闭文件流
fileInputStream.close();
4.读取不同类型的数据
先获取标题,再获取内容
@Test
public void readCellType() throws Exception {
FileInputStream fileInputStream = new FileInputStream(path + "test.xls");
//创建工作薄
Workbook workbook = new HSSFWorkbook(fileInputStream);
//获得工作表
Sheet sheet = workbook.getSheetAt(0);
//获取标题内容(第一行)
Row rowHead = sheet.getRow(0);
if (rowHead != null) {
//获取总数目
int cellCount = rowHead.getPhysicalNumberOfCells();
for (int cellNum = 0; cellNum < cellCount; cellNum++) {
Cell cell = rowHead.getCell(cellNum);
if (cell != null) {
String cellValue = cell.getStringCellValue();
System.out.print(cellValue + " | ");
}
}
System.out.println();
//读取表中内容
int rowCount = sheet.getPhysicalNumberOfRows();
for (int rowNum = 1; rowNum < rowCount; rowNum++) {
Row rowData = sheet.getRow(rowNum);
if (rowData != null) {
for (int cellNum=0;cellNum<cellCount;cellNum++){
Cell cell = rowData.getCell(cellNum);
//匹配列的数据类型
if(cell!=null){
int cellType = cell.getCellType();
String cellValue = "";
switch (cellType){
case CELL_TYPE_STRING:System.out.println("string类型");
cellValue = cell.getStringCellValue();
break;
case CELL_TYPE_BOOLEAN:System.out.println("boolean类型");
cellValue = String.valueOf(cell.getBooleanCellValue());
break;
case CELL_TYPE_NUMERIC:System.out.println("数字类型");
if(HSSFDateUtil.isCellDateFormatted(cell)){
System.out.println("日期");
Date date = cell.getDateCellValue();
cellValue =new DateTime(date).toString("yyyy-MM-dd");
}
else{
cellValue = String.valueOf(cell.getNumericCellValue());
}
break;
case CELL_TYPE_FORMULA:System.out.println("formula类型");
break;
case CELL_TYPE_BLANK:System.out.println("空");
break;
case CELL_TYPE_ERROR:System.out.println("类型错误");
break;
}
System.out.print(cellValue+" ");
}
}
System.out.println();
}
}
}
}
}