Java Mapping : Base64 Zipped CSV to XML Conversion

[former_member184944]

Introduction

 

In my recent client project i had a requirement where the incoming file was a csv file zipped and Base64 encoded. Source system was Ariba and Target was ECC.

My aim at writing this blog is to provide you with a reusable Java Mapping for similar requirements.

 

Description

 

Ariba sends file to PI using webservice. The encoded file is within a tag named "Header".

Following actions are required to be performed by PI before sending the file to ECC for further processing .

 

1. Decode base64 file

2. Unzip the content

3. Convert the unzipped CSV file into XML

 

In order to achive the above i have created a Java Mapping.

 

Incoming Payload

 

Encoded file is is within the "HeaderExport" Tag

 



 

CSV file after unzipping

 



 

 

Source Code : Please see attachment.

 

Output of the Mapping

 



 



 

package com.map;



import java.io.ByteArrayInputStream;

import java.lang.Object;

import java.io.ByteArrayOutputStream;

import java.io.InputStream;

import java.io.OutputStream;

import java.util.zip.ZipEntry;

import java.util.zip.ZipInputStream;



import org.w3c.dom.Element;

import javax.xml.bind.DatatypeConverter;

import javax.xml.parsers.DocumentBuilder;

import javax.xml.parsers.DocumentBuilderFactory;

import org.w3c.dom.Document;

import org.w3c.dom.NodeList;



import au.com.bytecode.opencsv.CSVReader;



import com.sap.aii.mapping.api.AbstractTransformation;

import com.sap.aii.mapping.api.StreamTransformationException;

import com.sap.aii.mapping.api.TransformationInput;

import com.sap.aii.mapping.api.TransformationOutput;





//csv start

import java.io.BufferedReader;

import java.io.ByteArrayInputStream;

import java.io.File;

import java.io.FileInputStream;

import java.io.FileOutputStream;

import java.io.IOException;

import java.io.InputStream;

import java.io.InputStreamReader;

import java.io.OutputStream;

import java.io.UnsupportedEncodingException;

import java.util.Map;

import java.util.Properties;

import java.util.StringTokenizer;



import com.sap.aii.mapping.api.AbstractTrace;

import com.sap.aii.mapping.api.DynamicConfiguration;

import com.sap.aii.mapping.api.DynamicConfigurationKey;

import com.sap.aii.mapping.api.StreamTransformation;

import com.sap.aii.mapping.api.StreamTransformationConstants;

import com.sap.aii.mapping.api.StreamTransformationException;



import javax.xml.transform.Result;

import javax.xml.transform.Source;

import javax.xml.transform.Transformer;

import javax.xml.transform.TransformerFactory;

import javax.xml.transform.dom.DOMSource;

import javax.xml.transform.Result;

import javax.xml.transform.Source;

import javax.xml.transform.Transformer;

import javax.xml.transform.TransformerFactory;

import javax.xml.transform.dom.DOMSource;

import javax.xml.transform.stream.StreamResult;



import org.w3c.dom.Document;



import org.w3c.dom.Node;

import org.w3c.dom.NodeList;



import com.sap.aii.mapping.api.AbstractTransformation;

import com.sap.aii.mapping.api.StreamTransformationException;

import com.sap.aii.mapping.api.TransformationInput;

import com.sap.aii.mapping.api.TransformationOutput;





//csv end



public class Base64DecodeAndUnzip extends AbstractTransformation {

	@SuppressWarnings("null")

	@Override

	public void transform(TransformationInput input, TransformationOutput output) throws

	StreamTransformationException {

		try {

			// Get base64 string from DOM input

			InputStream is = input.getInputPayload().getInputStream();

			DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();

			DocumentBuilder builder = factory.newDocumentBuilder();

			Document docIn = builder.parse(is);

			NodeList details = docIn.getElementsByTagName("HeaderExportFile");

			String b64 = details.item(0).getFirstChild().getNodeValue();

			//First decode the base 64 string

			byte[] decoded = DatatypeConverter.parseBase64Binary(b64);

			//Next, unzip the file (assumption only 1 entry in zip file)

			ZipInputStream zis = new ZipInputStream(new ByteArrayInputStream(decoded));

			ByteArrayOutputStream baos = new ByteArrayOutputStream();









			ZipEntry ze = zis.getNextEntry();

			if (ze != null) {

				byte[] buffer = new byte[1024];

				int read = 0;

				while ((read = zis.read(buffer, 0, buffer.length)) != -1) {

					baos.write(buffer, 0, read);

				}

				baos.flush();

				zis.closeEntry();

			}

			zis.close();





			//			//csvstart

			BufferedReader br = null;

			int rowsCount = -1;

			String line = "";

			String cvsSplitBy = ",";

			String result = "";

			String fresult = "";

			String[] records = null;

			String[] csvFields = null;

			int fieldCount = 0;

			InputStream inputStream = new ByteArrayInputStream(baos.toByteArray());

			String startElement =  "ContractId";

			DocumentBuilderFactory domFactory = null;

			DocumentBuilder domBuilder = null;

			StringTokenizer stringTokenizer = null;



			domFactory = DocumentBuilderFactory.newInstance();

			domBuilder = domFactory.newDocumentBuilder();





			Document newDoc = domBuilder.newDocument();

			Element rootElement = newDoc.createElement("Record");

			newDoc.appendChild(rootElement);

            



         

			br = new BufferedReader(new InputStreamReader(inputStream, "UTF-8"));



//			CSVReader readerCsv = new CSVReader(br, cvsSplitBy.charAt(0));

			

			if ((line = br.readLine()) != null)

			{



				//records = line.split(cvsSplitBy);

				stringTokenizer = new StringTokenizer(line, cvsSplitBy, false);

				

				if (stringTokenizer.countTokens() > 0 )

					while (stringTokenizer.hasMoreElements()){

						int i = 0 ;

						try{  



							result = stringTokenizer.nextElement().toString();

							i++;

						}

						catch(Exception e){

						}	

						break;

					}





			}



			if ((line = br.readLine()) != null)

			{



				//records = line.split(cvsSplitBy);

				stringTokenizer = new StringTokenizer(line, cvsSplitBy);

				if (stringTokenizer.countTokens() > 0 )

					csvFields = new String[stringTokenizer.countTokens()];

				int i = 0 ;

				while (stringTokenizer.hasMoreElements()){





					csvFields[i++] = String.valueOf(stringTokenizer.nextElement()).replaceAll(" ","" );



				}



			}



			// At this point the coulmns are known, now read data by lines

			while ((line = br.readLine()) != null) {

				stringTokenizer = new StringTokenizer(line, cvsSplitBy);

				fieldCount = stringTokenizer.countTokens();

				if (fieldCount > 0) {

					Element rowElement =  newDoc.createElement("row");

					int i = 0;

					while (stringTokenizer.hasMoreElements()) {

						try {

							String curValue = String.valueOf(stringTokenizer.nextElement()).replaceAll("\"","");

							

							Element curElement = newDoc.createElement(csvFields[i++]);

							

							curElement.appendChild(newDoc.createTextNode(curValue));

							rowElement.appendChild(curElement);

						} catch (Exception exp) {

						}

					}

					rootElement.appendChild(rowElement);

					rowsCount++;

				}

			}

			br.close();



			Transformer transformer = TransformerFactory.newInstance().newTransformer();

			Source source = new DOMSource(newDoc);

			Result outpayload = new StreamResult(output.getOutputPayload().getOutputStream());

			transformer.transform(source,outpayload);

			

		} catch (Exception e) {

			throw new StreamTransformationException("Exception: " + e.getMessage(), e);

		}

	}

}