我想要使用Java读取和写入一个具有3列和N行的Excel文件,并将每个单元格中的一个字符串打印出来。是否可以给我提供简单的代码片段?我需要使用任何外部库还是Java内置支持它?
我想要做以下事情:
for(i=0; i <rows; i++)
//read [i,col1] ,[i,col2], [i,col3]
for(i=0; i<rows; i++)
//write [i,col1], [i,col2], [i,col3]
要从 .xlsx 工作簿中读取数据,我们需要使用 XSSFworkbook 类。
XSSFWorkbook xlsxBook = new XSSFWorkbook(fis);
XSSFSheet sheet = xlsxBook.getSheetAt(0);
等等。
我们需要使用 Apache-poi 3.9 @ http://poi.apache.org/
有关详细信息和示例,请访问:http://java-recent.blogspot.in
if (fileName.endsWith(".xls")) {
File myFile = new File("file location" + fileName);
FileInputStream fis = new FileInputStream(myFile);
org.apache.poi.ss.usermodel.Workbook workbook = null;
try {
workbook = WorkbookFactory.create(fis);
} catch (InvalidFormatException e) {
e.printStackTrace();
}
org.apache.poi.ss.usermodel.Sheet sheet = workbook.getSheetAt(0);
Iterator<Row> rowIterator = sheet.iterator();
while (rowIterator.hasNext()) {
Row row = rowIterator.next();
Iterator<Cell> cellIterator = row.cellIterator();
while (cellIterator.hasNext()) {
Cell cell = cellIterator.next();
switch (cell.getCellType()) {
case Cell.CELL_TYPE_STRING:
System.out.print(cell.getStringCellValue());
break;
case Cell.CELL_TYPE_BOOLEAN:
System.out.print(cell.getBooleanCellValue());
break;
case Cell.CELL_TYPE_NUMERIC:
System.out.print(cell.getNumericCellValue());
break;
}
System.out.print(" - ");
}
System.out.println();
}
}
try {
POIFSFileSystem fs = new POIFSFileSystem(new FileInputStream(Dir));
HSSFWorkbook wb = new HSSFWorkbook(fs);
HSSFSheet sheet = wb.getSheetAt(0);
HSSFRow row;
HSSFCell cell;
int rows; // No of rows
rows = sheet.getPhysicalNumberOfRows();
int cols = 0; // No of columns
int tmp = 0;
int cblacks=0;
// This trick ensures that we get the data properly even if it doesn't start from first few rows
for(int i = 0; i <= 10 || i <= rows; i++) {
row = sheet.getRow(i);
if(row != null) {
tmp = sheet.getRow(i).getPhysicalNumberOfCells();
if(tmp >= cols) cols = tmp;else{rows++;cblacks++;}
}
cols++;
}
cols=cols+cblacks;
for(int r = 0; r < rows; r++) {
row = sheet.getRow(r);
if(row != null) {
for(int c = 0; c < cols; c++) {
cell = row.getCell(c);
if(cell != null) {
System.out.print(cell+"\n");//Your Code here
}
}
}
}} catch(Exception ioe) {
ioe.printStackTrace();}
package com.org.tests;
import org.apache.poi.xssf.usermodel.*;
import java.io.FileInputStream;
import java.io.IOException;
public class ExcelSimpleTest
{
String path;
public FileInputStream fis = null;
private XSSFWorkbook workbook = null;
private XSSFSheet sheet = null;
private XSSFRow row =null;
private XSSFCell cell = null;
public ExcelSimpleTest() throws IOException
{
path = System.getProperty("user.dir")+"\\resources\\Book1.xlsx";
fis = new FileInputStream(path);
workbook = new XSSFWorkbook(fis);
sheet = workbook.getSheetAt(0);
}
public void ExelWorks()
{
int index = workbook.getSheetIndex("Sheet1");
sheet = workbook.getSheetAt(index);
int rownumber=sheet.getLastRowNum()+1;
for (int i=1; i<rownumber; i++ )
{
row = sheet.getRow(i);
int colnumber = row.getLastCellNum();
for (int j=0; j<colnumber; j++ )
{
cell = row.getCell(j);
System.out.println(cell.getStringCellValue());
}
}
}
public static void main(String[] args) throws IOException
{
ExcelSimpleTest excelwork = new ExcelSimpleTest();
excelwork.ExelWorks();
}
}
相应的Maven依赖项可以在这里找到
你需要使用Apache POI库,以下代码应该能帮到你
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.Iterator;
//*************************************************************
import org.apache.poi.ss.usermodel.Sheet;
import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.ss.usermodel.Workbook;
import org.apache.poi.xssf.usermodel.XSSFSheet;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;
//*************************************************************
public class AdvUse {
private static Workbook wb ;
private static Sheet sh ;
private static FileInputStream fis ;
private static FileOutputStream fos ;
private static Row row ;
private static Cell cell ;
private static String ExcelPath ;
//*************************************************************
public static void setEcxelFile(String ExcelPath, String SheetName) throws Exception {
try {
File f= new File(ExcelPath);
if(!f.exists()){
f.createNewFile();
System.out.println("File not Found so created");
}
fis = new FileInputStream("./testData.xlsx");
wb = WorkbookFactory.create(fis);
sh = wb.getSheet("SheetName");
if(sh == null){
sh = wb.getSheet(SheetName);
}
}catch(Exception e)
{System.out.println(e.getMessage());
}
}
//*************************************************************
public static void setCellData(String text , int rowno , int colno){
try{
row = sh.getRow(rowno);
if(row == null){
row = sh.createRow(rowno);
}
cell = row.getCell(colno);
if(cell!=null){
cell.setCellValue(text);
}
else{
cell = row.createCell(colno);
cell.setCellValue(text);
}
fos = new FileOutputStream(ExcelPath);
wb.write(fos);
fos.flush();
fos.close();
}catch(Exception e){
System.out.println(e.getMessage());
}
}
//*************************************************************
public static String getCellData(int rowno , int colno){
try{
cell = sh.getRow(rowno).getCell(colno);
String CellData = null ;
switch(cell.getCellType()){
case STRING :
CellData = cell.getStringCellValue();
break ;
case NUMERIC :
CellData = Double.toString(cell.getNumericCellValue());
if(CellData.contains(".o")){
CellData = CellData.substring(0,CellData.length()-2);
}
break ;
case BLANK :
CellData = ""; break ;
}
return CellData;
}catch(Exception e){return ""; }
}
//*************************************************************
public static int getLastRow(){
return sh.getLastRowNum();
}
另一种读写Excel文件的方法是使用Windmill。它提供了一个流畅的API来处理Excel和CSV文件。
try (Stream<Row> rowStream = Windmill.parse(FileSource.of(new FileInputStream("myFile.xlsx")))) {
rowStream
// skip the header row that contains the column names
.skip(1)
.forEach(row -> {
System.out.println(
"row n°" + row.rowIndex()
+ " column 'User login' value : " + row.cell("User login").asString()
+ " column n°3 number value : " + row.cell(2).asDouble().value() // index is zero-based
);
});
}
Windmill
.export(Arrays.asList(bean1, bean2, bean3))
.withHeaderMapping(
new ExportHeaderMapping<Bean>()
.add("Name", Bean::getName)
.add("User login", bean -> bean.getUser().getLogin())
)
.asExcel()
.writeTo(new FileOutputStream("Export.xlsx"));
try
{
FileInputStream x = new FileInputStream(new File("/Users/rajesh/Documents/rajesh.xls"));
//Create Workbook instance holding reference to .xlsx file
Workbook workbook = new HSSFWorkbook(x);
//Get first/desired sheet from the workbook
Sheet sheet = workbook.getSheetAt(0);
//Iterate through each rows one by one
for (Iterator<Row> iterator = sheet.iterator(); iterator.hasNext();) {
Row row = (Row) iterator.next();
for (Iterator<Cell> iterator2 = row.iterator(); iterator2
.hasNext();) {
Cell cell = (Cell) iterator2.next();
System.out.println(cell.getStringCellValue());
}
}
x.close();
}
catch (Exception e)
{
e.printStackTrace();
}
}
}
在并行中,你不能同时读写同一个文件(读写锁)。但是,我们可以对临时数据(即输入/输出流)进行并行操作。只有在关闭输入流之后才将数据写入文件。应按照以下步骤进行操作。
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.sql.Date;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;
import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.xssf.usermodel.XSSFSheet;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;
public class XLSXReaderWriter {
public static void main(String[] args) {
try {
File excel = new File("D://raju.xlsx");
FileInputStream fis = new FileInputStream(excel);
XSSFWorkbook book = new XSSFWorkbook(fis);
XSSFSheet sheet = book.getSheetAt(0);
Iterator<Row> itr = sheet.iterator();
// Iterating over Excel file in Java
while (itr.hasNext()) {
Row row = itr.next();
// Iterating over each column of Excel file
Iterator<Cell> cellIterator = row.cellIterator();
while (cellIterator.hasNext()) {
Cell cell = cellIterator.next();
switch (cell.getCellType()) {
case Cell.CELL_TYPE_STRING:
System.out.print(cell.getStringCellValue() + "\t");
break;
case Cell.CELL_TYPE_NUMERIC:
System.out.print(cell.getNumericCellValue() + "\t");
break;
case Cell.CELL_TYPE_BOOLEAN:
System.out.print(cell.getBooleanCellValue() + "\t");
break;
default:
}
}
System.out.println("");
}
// writing data into XLSX file
Map<String, Object[]> newData = new HashMap<String, Object[]>();
newData.put("1", new Object[] { 1d, "Raju", "75K", "dev",
"SGD" });
newData.put("2", new Object[] { 2d, "Ramesh", "58K", "test",
"USD" });
newData.put("3", new Object[] { 3d, "Ravi", "90K", "PMO",
"INR" });
Set<String> newRows = newData.keySet();
int rownum = sheet.getLastRowNum();
for (String key : newRows) {
Row row = sheet.createRow(rownum++);
Object[] objArr = newData.get(key);
int cellnum = 0;
for (Object obj : objArr) {
Cell cell = row.createCell(cellnum++);
if (obj instanceof String) {
cell.setCellValue((String) obj);
} else if (obj instanceof Boolean) {
cell.setCellValue((Boolean) obj);
} else if (obj instanceof Date) {
cell.setCellValue((Date) obj);
} else if (obj instanceof Double) {
cell.setCellValue((Double) obj);
}
}
}
// open an OutputStream to save written data into Excel file
FileOutputStream os = new FileOutputStream(excel);
book.write(os);
System.out.println("Writing on Excel file Finished ...");
// Close workbook, OutputStream and Excel file to prevent leak
os.close();
book.close();
fis.close();
} catch (FileNotFoundException fe) {
fe.printStackTrace();
} catch (IOException ie) {
ie.printStackTrace();
}
}
}
当使用Apache POI 4.1.2时,单元格类型会有所改变。以下是一个示例
try {
File excel = new File("/home/name/Downloads/bb.xlsx");
FileInputStream fis = new FileInputStream(excel);
XSSFWorkbook book = new XSSFWorkbook(fis);
XSSFSheet sheet = book.getSheetAt(0);
Iterator<Row> itr = sheet.iterator();
// Iterating over Excel file in Java
while (itr.hasNext()) {
Row row = itr.next();
Iterator<Cell> cellIterator = row.cellIterator();
while (cellIterator.hasNext()) {
Cell cell = cellIterator.next();
switch (cell.getCellType()) {
case STRING:
System.out.print(cell.getStringCellValue() + "\t");
break;
case NUMERIC:
System.out.print(cell.getNumericCellValue() + "\t");
break;
case BOOLEAN:
System.out.print(cell.getBooleanCellValue() + "\t");
break;
default:
}
}
System.out.println("");}
}catch (Exception e) {
// TODO: handle exception
e.printStackTrace();
}
ExcelCell.getValue()
。例如,请参阅此读取示例,对于写入,您可以查看此示例。 - bellpatricia