Java tutorial
/* * To change this license header, choose License Headers in Project Properties. * To change this template file, choose Tools | Templates * and open the template in the editor. */ package com.firstbanknigeria.ofsaaenhancers.UI; import com.logix.utils.excel.ExcelProcessor; import com.vaadin.ui.Upload; import java.io.ByteArrayInputStream; import java.io.ByteArrayOutputStream; import java.io.IOException; import java.io.OutputStream; import java.util.List; import java.util.logging.Level; import java.util.logging.Logger; import org.apache.poi.openxml4j.exceptions.InvalidFormatException; /** * * @author mex */ public class AdjustmentFileProcessor implements Upload.Receiver, Upload.SucceededListener { ByteArrayOutputStream outStream; AdjustmentUI adjustmentUI; @Override public OutputStream receiveUpload(String filename, String mimeType) { System.out.println("byte stream"); outStream = new ByteArrayOutputStream(); return outStream; } @Override public void uploadSucceeded(Upload.SucceededEvent event) { try { ExcelProcessor excel = new ExcelProcessor(new ByteArrayInputStream(outStream.toByteArray())); List<List<String>> excelSheet = excel.getExcelSheet(0); adjustmentUI.setExcelContents(excelSheet); } catch (IOException ex) { Logger.getLogger(AdjustmentFileProcessor.class.getName()).log(Level.SEVERE, null, ex); } catch (InvalidFormatException ex) { Logger.getLogger(AdjustmentFileProcessor.class.getName()).log(Level.SEVERE, null, ex); } } public void setAdjustmentUI(AdjustmentUI adjustmentUI) { this.adjustmentUI = adjustmentUI; } }