Basic PI Java Mapping to copy the input to the output - identity mapping! #Java #mapping. The JavaMapCopy.java file shows how to copy to the input to the output with an InputStreamReader and a Stringbuffer. The IdentityMapWithXSL.java file includes a buildMessage() method which shows the same thing but with an XML Transformer instead. The benefi…

IdentityMapWithXSL.java

package au.com.inpex.mapping.lib;

import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.transform.OutputKeys;
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 au.com.inpex.mapping.lib.exceptions.BuildMessagePayloadException;
import au.com.inpex.mapping.lib.exceptions.SessionKeyResponseException;

import com.sap.aii.mapping.api.AbstractTrace;
import com.sap.aii.mapping.api.TransformationInput;
import com.sap.aii.mapping.api.TransformationOutput;
import com.sap.aii.mapping.lookup.Payload;


/**
 * Copy the input to the output and wrap in a soap header with the session key.
 * The soap header fields are defined by variables node and fieldName. These are
 * extracted from PI mapping parameters and are used as follows:
 * 
 * <node><fieldName>---sessionkey---</fieldName></node>
 * 
 * This scenario requires the receiver adapter to be in nosoap mode to allow us
 * manually construct the soap header. You cannot alter the soap header
 * otherwise.
 * 
 */
public class SessionMessageSoapHeaderImpl extends SessionMessage {
	private String prefix = "<?xml version=\"1.0\" encoding=\"UTF-8\"?>"
		+ "<soapenv:Envelope xmlns:soapenv=\"http://schemas.xmlsoap.org/soap/envelope/\" xmlns:urn=\"urn:pi:session:key\" xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\">"
		+ "<soapenv:Header>" + "<urn:SessionHeader>" + "<urn:sessionId>";
	private String suffix = "</urn:sessionId></urn:SessionHeader></soapenv:Header><soapenv:Body>";
	private String envelope = "</soapenv:Body></soapenv:Envelope>";
	
	private String nodeName = "";
	protected String newSessionIdFieldName = "";
	protected String sessionKeyResponseFieldName = "";
	
	
	SessionMessageSoapHeaderImpl(
		TransformationInput in,
		TransformationOutput out,
		String businessComponentName,
		String channelName,
		AsmaParameter dc,
		AbstractTrace trace,
		String payloadXml,
		String newSessionIdField,
		String sessionIdResponseField) {
		
		super(in, out, businessComponentName, channelName, dc, trace, payloadXml);
		
		try {
			this.nodeName = newSessionIdField.split("/")[0];
			this.newSessionIdFieldName = newSessionIdField.split("/")[1];
			
		} catch(ArrayIndexOutOfBoundsException e) {
			throw new RuntimeException("For SOAP_HEADER processing the newSessionIdField must be passed in the form: 'node/field'! You provided: " + newSessionIdField + ". " + e.getMessage());
		} 
		
		this.sessionKeyResponseFieldName = sessionIdResponseField;
	}
	
	@Override
	protected String getSessionKeyFromResponse(Payload response) {
		String sessionId = null;
		
		InputStream is = response.getContent();
		DocumentBuilderFactory docFactory = DocumentBuilderFactory.newInstance();
		try {
			DocumentBuilder builder = docFactory.newDocumentBuilder();
			Document document;
			document = builder.parse(is);
			NodeList nodes = document.getElementsByTagName(this.sessionKeyResponseFieldName);
			Node node = nodes.item(0);
			
			if (node != null) {
				node = node.getFirstChild();
				if (node != null) {
					sessionId = node.getNodeValue();
				}
			}
			
		} catch (Exception e) {
			throw new SessionKeyResponseException(e.getMessage());
		}
		
		return sessionId;
	}

	/**
	 * Copy input to output then wrap it in a soap envelope with
	 * the session Id in the soap header.
	 * Note: requires comm.channel to be in 'nosoap' mode.
	 */
	@Override
	protected void buildMessage(String sessionId) {		
		try {
			DocumentBuilderFactory docFactory = DocumentBuilderFactory.newInstance();
			ByteArrayOutputStream os = new ByteArrayOutputStream();
			
			try {
				DocumentBuilder builder = docFactory.newDocumentBuilder();
				Document document = builder.parse(this.messageInputstream);
				
				DOMSource source = new DOMSource(document);
				TransformerFactory transformerFactory = TransformerFactory.newInstance();
				Transformer transformer = transformerFactory.newTransformer();
				transformer.setOutputProperty(OutputKeys.OMIT_XML_DECLARATION, "yes");
				
				StreamResult streamResult = new StreamResult(os);
				transformer.transform(source, streamResult);
				
			} catch (Exception e) {
				throw new BuildMessagePayloadException(e.getMessage());
			}
			
			//Wrap payload in soap envelope/header
			prefix.replaceAll("SessionHeader", this.nodeName);
			prefix.replaceAll("sessionId", this.newSessionIdFieldName);
			
			this.messageOutputStream.write(prefix.getBytes());
			this.messageOutputStream.write(sessionId.getBytes());
			this.messageOutputStream.write(suffix.getBytes());
			this.messageOutputStream.write(os.toByteArray());
			this.messageOutputStream.write(envelope.getBytes());
			
		} catch (IOException e) {
			throw new BuildMessagePayloadException(e.getMessage());
		}
	}

}

JavaMapCopy.java

/* PI Java Mapping to copy the input to the output */
public class JavaMapCopy extends AbstractTransformation {
    InputStream is = null;
	
	public void transform(TransformationInput arg0, TransformationOutput arg1) 
		throws StreamTransformationException {
		
		execute(arg0.getInputPayload().getInputStream(), arg1.getOutputPayload().getOutputStream());
	}
	
	public void execute(InputStream is, OutputStream os) throws StreamTransformationException {
		
		// Copy input to output
		
		try {
			getTrace().addInfo("java mapping - processing start...");
		}
		catch (Exception e) { }

		char[] buffer = new char[100];
		StringBuilder str = new StringBuilder();
		
		Reader reader = new InputStreamReader(is);
		
		try {
			for (;;) {
				int read_size = reader.read(buffer, 0, buffer.length);
				if (read_size < 0) {
					break;
				}
				str.append(buffer, 0, read_size);
			}
		}
		catch (IOException e) {
			
		}
		finally {
			try {
				reader.close();
			}
			catch (IOException e) {
				
			}
		}
		
		PrintStream ps = new PrintStream(os);
		ps.print(str.toString());
	}
	
	public static void main(String[] args) {
		try {
			InputStream in = new FileInputStream(new File("C:\\in.xml"));
			OutputStream out = new FileOutputStream(new File("C:\\out.xml"));
			JavaMapCopy ident = new JavaMapCopy();
			indent.execute(in, out);
		}
		catch (Exception e) {
			e.printStackTrace();
		}
	}
}

And here's a better way:

import org.apache.commons.io.IOUtils;

//copy input to output
IOUtils.copy(arg0.getInputPayload().getInputStream(), arg1.getOutputPayload().getOutputStream());