fetch image from excel using java - java

I am working with Apache POI. I am able to read data from excel, but unable to read image from the excel. How to read image from excel.


Instead of puzzling around let's have a complete example.
import org.apache.poi.ss.usermodel.WorkbookFactory;
import org.apache.poi.ss.usermodel.Workbook;
import org.apache.poi.ss.usermodel.PictureData;
import java.io.InputStream;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.util.List;
import java.util.Iterator;
class ReadExcelImages {
public static void main(String[] args) throws Exception{
InputStream inp = new FileInputStream("test.xls");
//InputStream inp = new FileInputStream("test.xlsx");
Workbook workbook = WorkbookFactory.create(inp);
List lst = workbook.getAllPictures();
int i = 1;
for (Iterator it = lst.iterator(); it.hasNext(); ) {
PictureData pict = (PictureData)it.next();
String ext = pict.suggestFileExtension();
byte[] data = pict.getData();
if (ext.equals("png")){
FileOutputStream out = new FileOutputStream("pict" + i++ + ".png");
out.write(data);
out.close();
} else if (ext.equals("jpeg")) {
FileOutputStream out = new FileOutputStream("pict" + i++ + ".jpeg");
out.write(data);
out.close();
}
}
}
}
Works for me with HSSF (*.xls) as well as with XSSF (*.xlsx).

Related

Problem with formula when clone from a workbook to another workbook

The formula didn't work at new workbook when I try to clone an old workbook to new workbook. it just displayed value of 0. It might only work when I double-click on it and enter :(
package com.poi.xssf;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
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 Application {
public static void main(String[] args) throws Exception {
FileInputStream fisOld = null;
FileInputStream fisNew = null;
FileOutputStream fos = null;
//initialize vars
File fileOld = new File("test/copied.xlsx");
File fileNew = new File("test/test.xlsx");
fisOld = new FileInputStream(fileOld); // input: access A
//fisNew = new FileInputStream(fileNew);
XSSFWorkbook oldworkbook = new XSSFWorkbook(fisOld);
XSSFWorkbook newworkbook = oldworkbook;
XSSFSheet spreadsheet = newworkbook.getSheet("DeXuat");
Row row = spreadsheet.getRow(0);
Cell cell = row.getCell(0);
cell.setCellFormula("B1-C1");
fos = new FileOutputStream(fileNew);
newworkbook.write(fos);
}
}

how to reconstruct an org.archive.io.warc.WARCRecordInfo from an org.archive.io.ArchiveRecord?

Using java, I need to read a warc archive file, filter it depending on the content of the html page, and write a new archive file.
the following code reads the archive. how to reconstruct an org.archive.io.warc.WARCRecordInfo from an org.archive.io.ArchiveRecord?
import org.apache.commons.io.IOUtils;
import org.archive.io.ArchiveRecord;
import org.archive.io.warc.*;
import org.archive.wayback.resourcestore.resourcefile.WarcResource;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.io.OutputStream;
import java.util.Iterator;
import java.util.concurrent.atomic.AtomicInteger;
public class Test126b {
public static void main() throws Exception {
File out = new java.io.File("out.warc.gz");
OutputStream bos = new BufferedOutputStream(new FileOutputStream(out));
WARCWriterPoolSettings settings = ...
WARCWriter writer = new WARCWriter(new AtomicInteger(), bos, out, settings);
File in = new java.io.File("in.warc.gz");
WARCReader reader = WARCReaderFactory.get(in);
Iterator<ArchiveRecord> it = reader.iterator();
while (it.hasNext()) {
ArchiveRecord archiveRecord = it.next();
if (archiveRecord.getHeader().getHeaderValue("WARC-Type") == "response") {
WARCRecord warcRecord = (WARCRecord) archiveRecord;
WarcResource warcResource = new WarcResource(warcRecord, reader);
warcResource.parseHeaders();
String url = warcResource.getWarcHeaders().getUrl();
System.out.println("+++ url: " + url);
byte[] content = IOUtils.toByteArray(warcResource);
String htmlPage = new String(content);
if (htmlPage.contains("hello world")) {
writer.writeRecord(warcRecordInfo) // how to reconstruct the WARCRecordInfo
}
}
}
reader.close();
writer.close();
}
}

Reading and writing excel sheet using java apache POI

I am reading excel sheet using java apache POI. After reading i want to write on the same row, The ode is reading perfectly but not writing I want to create 6th column in every row in each iteration.... here is the code
/**
* Created by Muhammad Hussain on 26/10/2016.
*/
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.Iterator;
import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.ss.usermodel.Sheet;
import org.apache.poi.ss.usermodel.Workbook;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;
import java.util.Scanner;
/**
* A dirty simple program that reads an Excel file.
* #author www.codejava.net
*
*/
public class ReadExcel {
public static void main(String[] args) throws IOException {
String excelFilePath = "C:\\Users\\Muhammad Hussain\\Desktop\\Data-Collection.xlsx";
FileInputStream inputStream = new FileInputStream(new File(excelFilePath));
Workbook workbook = new XSSFWorkbook(inputStream);
Sheet firstSheet = workbook.getSheetAt(4);
Scanner input =new Scanner(System.in);
for (int rowIndex = 1; rowIndex <= 5; rowIndex++) {
Row row = firstSheet.getRow(rowIndex);
Cell cell = row.getCell(3);
String review = cell.getStringCellValue();
System.out.println(review);
String label =input.next();
row.createCell(6).setCellValue(label);
}
inputStream.close();
inputStream.close();
}
}

You are only reading the file and not writing it. You have to put something like this in the end:
FileOutputStream out = new FileOutputStream(new File("..."));
workbook.write(out);
out.close();

How to hide the data between the two tags(<hidden> .. </hidden>) in Word document

I am able to Read the input document using Apache POI and also able to find the data between the tags(What to be hidden) but the problem is i'm unable to write the data in the output file. How can i do the same to write the data and hide it in the output generated file..
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import org.apache.poi.hwpf.HWPFDocument;
import org.apache.poi.hwpf.extractor.WordExtractor;
import org.apache.poi.hwpf.usermodel.CharacterRun;
import org.apache.poi.hwpf.usermodel.Range;
public class Hidden {
public static void main(String args[]) throws Exception
{
File file = new File("D://me1.doc");
FileInputStream fin = new FileInputStream(file);
FileOutputStream fout = new FileOutputStream("D://Test.doc");
HWPFDocument doc = new HWPFDocument(fin);
Range range = doc.getRange();
WordExtractor extractor = new WordExtractor(doc);
String para[] = extractor.getParagraphText();
String output="";
String hidden="";
for (String p : para) {
String[] w = p.split("[<\\>]");
for(int k=0 ;k<w.length;k++){
if(w[k]!=null && !"".equalsIgnoreCase(w[k])){
if("hidden".equalsIgnoreCase(w[k])){
k++;
CharacterRun run = range.getCharacterRun(k);
hidden= w[k];
k++;
System.out.println(hidden);
run.setVanished(true);
doc.write(fout);
}else{
}
}
}
}
fout.close();
fin.close();
}
}

Overwriting an excel file using Java POI

I am new to Java POI and i am trying to overwrite an excel file using Java POI.Let me make it clear, i don't want to open a new .xls file every time time i build the code however the code i wrote does it that way.The purpose for this is to, i will build the chart on excel and read the values for the chart from the database and write it to the excel file by using Java POI.Here is my code:
HSSFWorkbook workbook = new HSSFWorkbook();
HSSFSheet firstSheet = workbook.createSheet("oldu");
HSSFSheet secondSheet = workbook.createSheet("oldu2");
HSSFRow rowA = firstSheet.createRow(6);
HSSFCell cellA = rowA.createCell(3);
cellA.setCellValue(new HSSFRichTextString("100"));
cellA.setCellValue(100);
HSSFRow rowB = secondSheet.createRow(0);
HSSFCell cellB = rowB.createCell(0);
cellB.setCellValue(new HSSFRichTextString("200"));
FileOutputStream fos = null;
try {
fos = new FileOutputStream(new File("CreateExcelDemo.xls"));
workbook.write(fos);
} catch (IOException e) {
e.printStackTrace();
} finally {
if (fos != null) {
try {
fos.flush();
fos.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}

Always use the same filename and when you run the program it will overwrite the file.
EDIT
If you want to modify an existing excel file then have a look HERE and scroll down to the section on "Reading or Modifying an existing file".

The problem is Apache POI doesn't support all features of Excel file format, including charts. So can not generate a chart with POI and when opening an existing Excel file with POI and modifying it, some of the current "objects" in the Excel file could be lost, as POI can't handle it and when writing, writes only the new information generated and existing one that can handle.
This is assumed by Apache as one of the flaws of POI.
We done similar processing of existing Excel file, filling new data onto it, but the existing Excel file contains only formatting styles and they are preserved using POI, but I think charts are very problematic. Trying ti filling data to update an existing chart is not possible with POI.

import org.apache.poi.openxml4j.exceptions.InvalidFormatException;
import org.apache.poi.ss.usermodel.*;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.HashMap;
import java.util.Map;
public class UserInput {
public static Map getUserInput() throws InvalidFormatException, IOException {
String userName = System.getProperty("user.name");
String path = "";
int indexofColumn = 10;
Map inputFromExcel = new HashMap();
InputStream inp = new FileInputStream(path);
int ctr = 4;
Workbook wb = WorkbookFactory.create(inp);
Sheet sheet = wb.getSheetAt(0); // Mention Sheet no. which you want to read
Row row = null;
Cell cell = null;
try{
row = sheet.getRow(ctr);
cell = row.getCell(indexofColumn); //Mention column no. which you want to read
inputFromExcel.put("NBKID",cell.toString()) ;
row = sheet.getRow(ctr+1);
cell = row.getCell(indexofColumn);
inputFromExcel.put("Password", cell.toString());
row = sheet.getRow(ctr+2);
cell = row.getCell(indexofColumn);
inputFromExcel.put("NBKIDEmail",cell.toString());
row = sheet.getRow(ctr+3);
cell = row.getCell(indexofColumn);
inputFromExcel.put("sourceExcel" ,cell.toString());
} catch(Exception e) {
}
return inputFromExcel;
}
}

import java.util;
public class Main {
public static void main(String[] args) {
List<String> partyIdList = new ArrayList<String>();
List<String> phNoList = new ArrayList<String>();
String userName = System.getProperty("user.name");
String path = "";
try {
Map data = new HashMap(UserInput.getUserInput());
partyIdList = ReadExcel.getContentFromExcelSheet(data.get("sourceExcel").toString(),0);
phNoList = ReadExcel.getContentFromExcelSheet(data.get("sourceExcel").toString(),1);
WriteExcel.writeFile1(partyIdList, path,0,1);
WriteExcel.writeFile1(phNoList,path,1,0);
} catch (Exception e) {
throw new RuntimeException("Error while read excel Sheet" + e);
}
}
}

import org.apache.poi.openxml4j.exceptions.InvalidFormatException;
import org.apache.poi.ss.usermodel.*;
import java.io.*;
import java.util.List;
public class WriteExcel {
public static void writeFile1(List dataList , String path , int columnCount,int forwardIndex) throws InvalidFormatException, IOException {
try {
FileInputStream inputStream = new FileInputStream(new File(path));
Workbook workbook = WorkbookFactory.create(inputStream);
Sheet sheet = workbook.getSheetAt(0);
int rowCount = 1;
for ( int i = 0+forwardIndex ; i < dataList.size(); i++) {
Row row = sheet.createRow(++rowCount);
// int columnCount = 0;
Cell cell = row.createCell(columnCount);
cell.setCellValue((String) dataList.get(i));
}
inputStream.close();
FileOutputStream outputStream = new FileOutputStream(path);
workbook.write(outputStream);
workbook.close();
outputStream.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
import org.apache.poi.openxml4j.exceptions.InvalidFormatException;
import org.apache.poi.ss.usermodel.*;
import java.io.*;
import java.util.List;
public class WriteExcel {
public static void writeFile1(List dataList , String path , int columnCount,int forwardIndex) throws InvalidFormatException, IOException {
try {
FileInputStream inputStream = new FileInputStream(new File(path));
Workbook workbook = WorkbookFactory.create(inputStream);
Sheet sheet = workbook.getSheetAt(0);
int rowCount = 1;
for ( int i = 0+forwardIndex ; i < dataList.size(); i++) {
Row row = sheet.createRow(++rowCount);
// int columnCount = 0;
Cell cell = row.createCell(columnCount);
cell.setCellValue((String) dataList.get(i));
}
inputStream.close();
FileOutputStream outputStream = new FileOutputStream(path);
workbook.write(outputStream);
workbook.close();
outputStream.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}

import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.ArrayList;
import java.util.List;
import org.apache.poi.openxml4j.exceptions.InvalidFormatException;
import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.ss.usermodel.Sheet;
import org.apache.poi.ss.usermodel.Workbook;
import org.apache.poi.ss.usermodel.WorkbookFactory;
public class ReadExcel {
public static List getContentFromExcelSheet(String path ,int indexofColumn) throws InvalidFormatException, IOException {
//System.out.println(path);
List<String> ItemList = new ArrayList();
InputStream inp = new FileInputStream(path);
int ctr = 0;
Workbook wb = WorkbookFactory.create(inp);
Sheet sheet = wb.getSheetAt(0); // Mention Sheet no. which you want to read
Row row = null;
Cell cell = null;
boolean isNull = false;
do{
try{
row = sheet.getRow(ctr);
cell = row.getCell(indexofColumn); //Mention column no. which you want to read
ItemList.add(cell.toString());
// System.out.println(cell.toString());
ctr++;
} catch(Exception e) {
isNull = true;
}
}while(isNull!=true);
inp.close();
return ItemList;
}
}

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