How do I unpack an ISO 8583 message?

By I Wayan Saryada in jPOS 15 Comments

The code snippet below will show you how to unpack ISO 8583 message.

package org.kodejava.jpos;

import org.jpos.iso.ISOException;
import org.jpos.iso.ISOMsg;
import org.jpos.iso.packager.GenericPackager;

import java.io.InputStream;

public class UnpackISOMessage {
    public static void main(String[] args) {
        UnpackISOMessage iso = new UnpackISOMessage();
        try {
            ISOMsg isoMsg = iso.parseISOMessage();
            iso.printISOMessage(isoMsg);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    private ISOMsg parseISOMessage() throws Exception {
        String message = "02003220000000808000000010000000001500120604120000000112340001840";
        System.out.printf("Message = %s%n", message);
        try {
            // Load package from resources directory.
            InputStream is = getClass().getResourceAsStream("/fields.xml");
            GenericPackager packager = new GenericPackager(is);
            ISOMsg isoMsg = new ISOMsg();
            isoMsg.setPackager(packager);
            isoMsg.unpack(message.getBytes());
            return isoMsg;
        } catch (ISOException e) {
            throw new Exception(e);
        }
    }

    private void printISOMessage(ISOMsg isoMsg) {
        try {
            System.out.printf("MTI = %s%n", isoMsg.getMTI());
            for (int i = 1; i <= isoMsg.getMaxField(); i++) {
                if (isoMsg.hasField(i)) {
                    System.out.printf("Field (%s) = %s%n", i, isoMsg.getString(i));
                }
            }
        } catch (ISOException e) {
            e.printStackTrace();
        }
    }
}

When you run the program you’ll get the following output:

Message = 02003220000000808000000010000000001500120604120000000112340001840
MTI = 0200
Field (3) = 000010
Field (4) = 000000001500
Field (7) = 1206041200
Field (11) = 000001
Field (41) = 12340001
Field (49) = 840

The xml packager (fields.xml) can be downloaded from the following link: fields.xml.

Maven Dependency

<dependency>
    <groupId>org.jpos</groupId>
    <artifactId>jpos</artifactId>
    <version>2.1.8</version>
</dependency>

Maven Central

How do I pack an ISO 8583 message?

By I Wayan Saryada in jPOS 30 Comments

The code snippet below show you how to pack an ISO 8583 message.

package org.kodejava.jpos;

import org.jpos.iso.ISOException;
import org.jpos.iso.ISOMsg;
import org.jpos.iso.packager.GenericPackager;

import java.io.InputStream;

public class PackISOMessage {
    public static void main(String[] args) {
        PackISOMessage iso = new PackISOMessage();
        try {
            String message = iso.buildISOMessage();
            System.out.printf("Message = %s", message);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    private String buildISOMessage() throws Exception {
        try {
            // Load package from resources directory.
            InputStream is = getClass().getResourceAsStream("/fields.xml");
            GenericPackager packager = new GenericPackager(is);

            ISOMsg isoMsg = new ISOMsg();
            isoMsg.setPackager(packager);
            isoMsg.setMTI("0200");

            isoMsg.set(3, "000010");
            isoMsg.set(4, "1500");
            isoMsg.set(7, "1206041200");
            isoMsg.set(11, "000001");
            isoMsg.set(41, "12340001");
            isoMsg.set(49, "840");
            printISOMessage(isoMsg);

            byte[] result = isoMsg.pack();
            return new String(result);
        } catch (ISOException e) {
            throw new Exception(e);
        }
    }

    private void printISOMessage(ISOMsg isoMsg) {
        try {
            System.out.printf("MTI = %s%n", isoMsg.getMTI());
            for (int i = 1; i <= isoMsg.getMaxField(); i++) {
                if (isoMsg.hasField(i)) {
                    System.out.printf("Field (%s) = %s%n", i, isoMsg.getString(i));
                }
            }
        } catch (ISOException e) {
            e.printStackTrace();
        }
    }
}

When you run the program you’ll get the following output:

MTI = 0200
Field (3) = 000010
Field (4) = 1500
Field (7) = 1206041200
Field (11) = 000001
Field (41) = 12340001
Field (49) = 840
Message = 02003220000000808000000010000000001500120604120000000112340001840

The xml packager (fields.xml) can be downloaded from the following link: fields.xml.

Maven Dependency

<dependency>
    <groupId>org.jpos</groupId>
    <artifactId>jpos</artifactId>
    <version>2.1.8</version>
</dependency>

Maven Central

How do I define a filter using @WebFilter annotation?

By I Wayan Saryada in Servlet 0 Comment

The following example show you how to create a servlet filter using the @WebFilter annotation. We will create a simple filter that will check whether an attribute is exists in the http session object. If no attribute found this filter will redirect user into a login page.

package org.kodejava.filter;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

@WebFilter(urlPatterns = "/*", description = "Session Checker Filter")
public class SessionCheckerFilter implements Filter {
    private FilterConfig config = null;

    public void init(FilterConfig config) throws ServletException {
        this.config = config;
        config.getServletContext().log("Initializing SessionCheckerFilter");
    }

    public void doFilter(ServletRequest req, ServletResponse res,
                         FilterChain chain)
            throws ServletException, IOException {

        HttpServletRequest request = (HttpServletRequest) req;
        HttpServletResponse response = (HttpServletResponse) res;

        //
        // Check to see if user's session attribute contains an attribute
        // named AUTHENTICATED. If the attribute is not exists redirect
        // user to the login page.
        //
        if (!request.getRequestURI().endsWith("login.jsp") &&
                request.getSession().getAttribute("AUTHENTICATED") == null) {
            response.sendRedirect(request.getContextPath() + "/login.jsp");
        }
        chain.doFilter(req, res);
    }

    public void destroy() {
        config.getServletContext().log("Destroying SessionCheckerFilter");
    }
}

Before the birth of @WebFilter annotation as defined in the Servlet 3.0 Specification. To make the filter functional we must register it in the web.xml file by using the filter and the filter-mapping element. And once it active it will collaborate with the other filters in the filter chain for the current servlet context.

Maven dependencies

<dependency>
    <groupId>javax.servlet</groupId>
    <artifactId>javax.servlet-api</artifactId>
    <version>4.0.1</version>
</dependency>

Maven Central

How do I draw a vertical text in Java 2D?

By I Wayan Saryada in 2D API, Core API 0 Comment

To draw a text / string vertically we need to do a transform on the Graphics2D object. First, create an instance of AffineTransform and set the rotation using the setToRotation() method. And then pass this transform object into g2.setTransform() method.

package org.kodejava.awt.geom;

import javax.swing.*;
import java.awt.*;
import java.awt.geom.AffineTransform;

public class DrawVerticalText extends JPanel {
    public static void main(String[] args) {
        JFrame frame = new JFrame();
        frame.setTitle("Draw Vertical Text Demo");
        frame.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
        frame.add(new DrawVerticalText());
        frame.pack();
        frame.setSize(420, 350);
        frame.setVisible(true);
    }

    @Override
    public void paint(Graphics g) {
        Graphics2D g2 = (Graphics2D) g;

        // Define rendering hint, font name, font style and font size
        g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
        g2.setFont(new Font("Segoe Script", Font.BOLD, 22));
        g2.setColor(Color.RED);

        // Rotate 90 degree to make a vertical text
        AffineTransform at = new AffineTransform();
        at.setToRotation(Math.toRadians(90), 80, 100);
        g2.setTransform(at);
        g2.drawString("This is a vertical text", 10, 10);
    }
}

Run the snippet, and you’ll see the following screen:

Draw 2D Vertical Text

Draw 2D Vertical Text

How do I define a servlet with @WebServlet annotation?

By I Wayan Saryada in Servlet 0 Comment

Annotations is one new feature introduces in the Servlet 3.0 Specification. Previously to declare servlets, listeners or filters we must do it in the web.xml file. Now, with the new annotations feature we can just annotate servlet classes using the @WebServlet annotation.

package org.kodejava.servlet;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebInitParam;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.PrintWriter;

@WebServlet(
        name = "HelloAnnotationServlet",
        urlPatterns = {"/hello", "/helloanno"},
        asyncSupported = false,
        initParams = {
                @WebInitParam(name = "name", value = "admin"),
                @WebInitParam(name = "param1", value = "value1"),
                @WebInitParam(name = "param2", value = "value2")
        }
)
public class HelloAnnotationServlet extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        response.setContentType("text/html");

        PrintWriter out = response.getWriter();
        out.write("<html><head><title>WebServlet Annotation</title></head>");
        out.write("<body>");
        out.write("<h1>Servlet Hello Annotation</h1>");
        out.write("<hr/>");
        out.write("Welcome " + getServletConfig().getInitParameter("name"));
        out.write("</body></html>");
        out.close();
    }
}

After you’ve deploy the servlet you’ll be able to access it either using the /hello or /helloanno url.

The table below give brief information about the attributes accepted by the @WebServlet annotation and their purposes.

ATTRIBUTE DESCRIPTION
name The servlet name, this attribute is optional.
description The servlet description and it is an optional attribute.
displayName The servlet display name, this attribute is optional.
urlPatterns An array of url patterns use for accessing the servlet, this attribute is required and should at least register one url pattern.
asyncSupported Specifies whether the servlet supports asynchronous processing or not, the value can be true or false.
initParams An array of @WebInitParam, that can be used to pass servlet configuration parameters. This attribute is optional.
loadOnStartup An integer value that indicates servlet initialization order, this attribute is optional.
smallIcon A small icon image for the servlet, this attribute is optional.
largeIcon A large icon image for the servlet, this attribute is optional.

Maven dependencies

<dependency>
    <groupId>javax.servlet</groupId>
    <artifactId>javax.servlet-api</artifactId>
    <version>4.0.1</version>
</dependency>

Maven Central