One Way Tweet a Java App

Siriquelle — Fri, 31 Jul 2009 09:33:31 +0000

One way tweet is a sending application for twitter. In this tutorial you will see/learn how to send stuff to twitter by writing a java desktop UI. You will create a new project in NetBeans and choose java application, and create a new package called org.me.owt.

Then, create a new java source file and call it main.java, and another called tweet.java. Two simple classes and you’ve got yourself a twitter client. The end result will look like this:

/*
 * Main.java
 *
 * Created on 23-Jul-2009, 11:57:04
 */
package org.me.owt;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;

/**
 *
 * @author Siriquelle
 */
public class Main extends javax.swing.JFrame {

    private JButton button;

    /** Creates new form Main*/
    public Main() {
        initComponents();
    }

    /** This method is called from within the constructor to
     * initialize the form.
     * WARNING: Do NOT modify this code. The content of this method is
     * always regenerated by the Form Editor.
     */
    @SuppressWarnings("unchecked")
    // 
    private void initComponents() {

        jPanel1 = new javax.swing.JPanel();
        usernamelabel = new java.awt.Label();
        username = new java.awt.TextField();
        passwordlabel = new java.awt.Label();
        password = new java.awt.TextField();
        status = new java.awt.TextArea();
        tweet = new java.awt.Button();

        setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
        setTitle("One Way Tweet");
        setBackground(new java.awt.Color(204, 255, 255));
        setBounds(new java.awt.Rectangle(0, 0, 0, 0));
        setCursor(new java.awt.Cursor(java.awt.Cursor.DEFAULT_CURSOR));
        setForeground(new java.awt.Color(204, 255, 255));
        setName("One Way Tweet"); // NOI18N
        setResizable(false);

        jPanel1.setBackground(new java.awt.Color(204, 255, 255));
        jPanel1.setBorder(new javax.swing.border.SoftBevelBorder(javax.swing.border.BevelBorder.RAISED));
        jPanel1.setAlignmentX(getWidth() / 2);
        jPanel1.setAlignmentY(getHeight() / 2);

        usernamelabel.setFont(new java.awt.Font("Dialog", 1, 14)); // NOI18N
        usernamelabel.setForeground(new java.awt.Color(0, 102, 102));
        usernamelabel.setName("usernameLabel"); // NOI18N
        usernamelabel.setText("Username");

        username.setForeground(new java.awt.Color(51, 51, 51));
        username.setName("username"); // NOI18N
        username.addFocusListener(new java.awt.event.FocusAdapter() {

            public void focusGained(java.awt.event.FocusEvent evt) {
                Main.this.focusGained(evt);
            }

            public void focusLost(java.awt.event.FocusEvent evt) {
                Main.this.focusLost(evt);
            }
        });

        passwordlabel.setFont(new java.awt.Font("Dialog", 1, 14)); // NOI18N
        passwordlabel.setForeground(new java.awt.Color(0, 102, 102));
        passwordlabel.setName("passwordLabel"); // NOI18N
        passwordlabel.setText("Password");

        password.setEchoChar('*');
        password.setForeground(new java.awt.Color(51, 51, 51));
        password.setName("password"); // NOI18N
        password.addFocusListener(new java.awt.event.FocusAdapter() {

            public void focusGained(java.awt.event.FocusEvent evt) {
                Main.this.focusGained(evt);
            }

            public void focusLost(java.awt.event.FocusEvent evt) {
                Main.this.focusLost(evt);
            }
        });

        status.setForeground(new java.awt.Color(51, 51, 51));
        status.setName("status"); // NOI18N
        status.addFocusListener(new java.awt.event.FocusAdapter() {

            @Override
            public void focusGained(java.awt.event.FocusEvent evt) {
                Main.this.focusGained(evt);
            }

            @Override
            public void focusLost(java.awt.event.FocusEvent evt) {
                Main.this.focusLost(evt);
            }
        });

        tweet.setActionCommand("tweet");
        tweet.setBackground(new java.awt.Color(153, 255, 255));
        tweet.setFont(new java.awt.Font("Impact", 1, 48)); // NOI18N
        tweet.setForeground(new java.awt.Color(0, 102, 102));
        tweet.setLabel("tweet");
        tweet.setName("tweet"); // NOI18N
        tweet.addMouseListener(new java.awt.event.MouseAdapter() {

            public void mouseClicked(java.awt.event.MouseEvent evt) {
                tweetMouseClicked(evt);
            }
        });

        javax.swing.GroupLayout jPanel1Layout = new javax.swing.GroupLayout(jPanel1);
        jPanel1.setLayout(jPanel1Layout);
        jPanel1Layout.setHorizontalGroup(
                jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING).addGroup(jPanel1Layout.createSequentialGroup().addContainerGap().addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING).addComponent(status, javax.swing.GroupLayout.PREFERRED_SIZE, 266, javax.swing.GroupLayout.PREFERRED_SIZE).addGroup(jPanel1Layout.createSequentialGroup().addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING, false).addComponent(passwordlabel, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE).addComponent(usernamelabel, javax.swing.GroupLayout.PREFERRED_SIZE, 83, javax.swing.GroupLayout.PREFERRED_SIZE)).addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED).addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING).addComponent(username, javax.swing.GroupLayout.PREFERRED_SIZE, 173, javax.swing.GroupLayout.PREFERRED_SIZE).addComponent(password, javax.swing.GroupLayout.PREFERRED_SIZE, 173, javax.swing.GroupLayout.PREFERRED_SIZE))).addComponent(tweet, javax.swing.GroupLayout.PREFERRED_SIZE, 266, javax.swing.GroupLayout.PREFERRED_SIZE)).addContainerGap()));
        jPanel1Layout.setVerticalGroup(
                jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING).addGroup(jPanel1Layout.createSequentialGroup().addContainerGap().addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.TRAILING).addComponent(usernamelabel, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE).addComponent(username, javax.swing.GroupLayout.PREFERRED_SIZE, 20, javax.swing.GroupLayout.PREFERRED_SIZE)).addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED).addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING).addComponent(passwordlabel, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE).addComponent(password, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)).addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED).addComponent(status, javax.swing.GroupLayout.PREFERRED_SIZE, 91, javax.swing.GroupLayout.PREFERRED_SIZE).addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED).addComponent(tweet, javax.swing.GroupLayout.PREFERRED_SIZE, 79, javax.swing.GroupLayout.PREFERRED_SIZE).addContainerGap()));

        usernamelabel.getAccessibleContext().setAccessibleName("usernameLabel");
        username.getAccessibleContext().setAccessibleName("username");
        password.getAccessibleContext().setAccessibleName("password");
        status.getAccessibleContext().setAccessibleName("status");
        tweet.getAccessibleContext().setAccessibleName("tweet");

        javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
        getContentPane().setLayout(layout);
        layout.setHorizontalGroup(
                layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING).addComponent(jPanel1, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE));
        layout.setVerticalGroup(
                layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING).addComponent(jPanel1, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE));

        getAccessibleContext().setAccessibleName("One Way Tweet");
        getAccessibleContext().setAccessibleDescription("One Way Tweet");

        pack();
    }// 

    private void tweetMouseClicked(java.awt.event.MouseEvent evt) {
        Tweet tw = new Tweet(username.getText(), password.getText(), status.getText());
        if (tw.sendTweet())
        {
            this.ShowMessageDialog("Tweet Win");
        } else
        {
            this.ShowMessageDialog("Tweet Fail");
        }
    }

    private void focusGained(java.awt.event.FocusEvent evt) {
        evt.getComponent().setBackground(new java.awt.Color(255, 255, 215));
    }

    private void focusLost(java.awt.event.FocusEvent evt) {
        evt.getComponent().setBackground(new java.awt.Color(255, 255, 255));
    }

    public void ShowMessageDialog(String msg) {
        final JFrame frame = new JFrame(msg);
        button = new JButton("OK");
        button.addMouseListener(new java.awt.event.MouseAdapter() {

            public void mouseClicked(java.awt.event.MouseEvent evt) {
                frame.dispose();
            }
        });

        JPanel panel = new JPanel();
        panel.add(button);
        panel.add(button);
        frame.add(panel);
        frame.setSize(220, 80);
        frame.setLocation(220, 80);
        frame.setVisible(true);
        frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
    }

    /**
     * @param args the command line arguments
     */
    public static void main(String args[]) {
        java.awt.EventQueue.invokeLater(new Runnable() {

            public void run() {
                new Main().setVisible(true);
            }
        });
    }

    // Variables declaration - do not modify
    private javax.swing.JPanel jPanel1;
    private java.awt.TextField password;
    private java.awt.Label passwordlabel;
    private java.awt.TextArea status;
    private java.awt.Button tweet;
    private java.awt.TextField username;
    private java.awt.Label usernamelabel;
    // End of variables declaration
}

The following code is a class that handles the tweet. create a new java source file in the org.me.owt package and call it tweet.java. It’s methods are used to create and send the tweet and handle the response from the twitter api:

/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */
package org.me.owt;

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.net.URL;
import java.net.URLConnection;
import java.net.URLEncoder;

/**
 *
 * @author Siriquelle
 */
public class Tweet {

    private String twitteruser;
    private String twitterpass;
    private String status;
    private String response;

    public Tweet(String u, String p, String s) {
        twitteruser = u;
        twitterpass = p;
        status = s;
    }

    public boolean sendTweet() {
        try
        {
            String encodedData = URLEncoder.encode(status, "UTF-8");

            String credentials = twitteruser + ":" + twitterpass;
            String encodecredentials = new sun.misc.BASE64Encoder().encode(credentials.getBytes());

            URLConnection connection = null;
            URL url = new URL("http://twitter.com/statuses/update.xml");
            connection = url.openConnection();
            connection.setRequestProperty("Authorization", "Basic " + encodecredentials);
            connection.setDoOutput(true);

            OutputStreamWriter output = new OutputStreamWriter(connection.getOutputStream());
            output.write("status=" + encodedData);
            output.close();

            BufferedReader in = new BufferedReader(new InputStreamReader(connection.getInputStream()));
            String decodedString;
            while ((decodedString = in.readLine()) != null)
            {
                response = decodedString;
            }
            in.close();
            return true;
        } catch (Exception e)
        {
            response = e.toString();
            return false;
        }
    }
}

And thats the code, right click your project and choose run. After you examine this code you’ll discover how, with a little parsing you can turn this application into a fully fledged thwirl competitor. :) If you’ve any questions I’d love a go at answering.

This application was created in netbeans using the swing UI builder. In a future post I will describe the process to building an application using the NetBeans IDE and it’s UI builders in design view.

Creating a PDF Programmatically with iText

Siriquelle — Wed, 08 Jul 2009 17:00:29 +0000

All will agree that pdf’s are cool, right? So, In this brief tutorial I will be describing how to create a pdf programmaticallywith NetBeans and how to add the iText library to your NetBeans projects. As is always the case this tutorial is intended to wet your appetite for the iText library. When you get serious you’ll want to create shapes and play with colors. In this tutorial I will show you how to create a pdf that shows a big Hello World at the top and draws eight squares underneath it. Here is the finished product, you can play around with the collors and draw loop to add more effects.

First thing you will need to have a copy of NetBeans. And also a copy of the iText Core jar. In Netbeans you will want to create a new project, call it “HelloWorld”. A this point you should create a new package, call it “pdfbuilder”.

Right click the package pdfbuilder you’ve just created and select New > Java Class:

You will need to give the class a name so for this example you should call it HelloWorld then hit finish:

Before we continue with the fun part we need to create a library for our iText jar and add it to the project. To do this all you have to do is Right Click on the libraries icon and select Add Library:

Create a new Library and name it iText:

Add the iText Core jar that was downloaded earlier:

Now your HelloWorld.java is ready to accept the following code:

package pdfbuilder;

import java.io.FileOutputStream;
import com.lowagie.text.Document;
import com.lowagie.text.Element;
import com.lowagie.text.pdf.BaseFont;
import com.lowagie.text.pdf.PdfContentByte;
import com.lowagie.text.pdf.PdfWriter;

public class HelloWorld {

    public static void main(String[] args) {
        try
        {
            //
            Document document = new Document();
            PdfWriter writer = PdfWriter.getInstance(document, new FileOutputStream("c:/world.pdf"));
            document.open();

            //
            PdfContentByte cb = writer.getDirectContent();
            cb.beginText();
            BaseFont bf = BaseFont.createFont(BaseFont.HELVETICA,
                    BaseFont.CP1252, BaseFont.NOT_EMBEDDED);
            cb.setFontAndSize(bf, 39);
            cb.setRGBColorFill(0xcc, 0x66, 0x66);
            cb.showTextAligned(Element.ALIGN_LEFT, "Hello World :)", 36, 788, 0);
            cb.endText();

            //
            cb.setRGBColorFill(0x9a, 0xe4, 0xe8);
            for (int i = 0, j = 55; i < (j * 8); i += j)
            {
                cb.roundRectangle(36 + i, 718, 50, 50, 5);
            }
            cb.eoFill();

            //
            document.close();
        } catch (Exception e)
        {
            System.out.println(e);
        }
    }
}

What you get after you run this program is a file named world.pdf in the root of your c:/ drive.

Threadbare Canvas Productions » Java

One Way Tweet a Java App

Creating a PDF Programmatically with iText