Lanzar un navegador desde java

Bare Bones Browser
Launch for Java

Use Default Browser to Open a Web Page from a Swing Application

Java is often touted as the programing language of the Internet, so you would think Java might include a standard platform-independent mechanism to launch the user's default web browser. Unfortunately, this commonly needed feature is left to the application developer to build, and it's not easy. Two open source projects exist specifically to address this problem -- BrowserLauncher and BrowserLauncher2. The BrowserLauncher2 project is more current and is an industrial strength solution packed with advanced features and even supports old browsers and old OSes.

Bare Bones

The Bare Bones Browser Launch solution, on the other hand, is intended for those with much simpler requirements or those just looking for an educational "Hello, World" type tutorial on the subject. This solution is appropriate when a compact lightweight method will suffice which limits support to the most current browsers and OSes. Bare Bones is free and works on Mac OS X, GNU/Linux, Unix (Solaris), and Windows XP.

Let's jump straight to the code:

BareBonesBrowserLaunch.java

///////////////////////////////////////////////////////// // Bare Bones Browser Launch // // Version 1.5 // // December 10, 2005 // // Supports: Mac OS X, GNU/Linux, Unix, Windows XP // // Example Usage: // // String url = "http://www.centerkey.com/"; // // BareBonesBrowserLaunch.openURL(url); // // Public Domain Software -- Free to Use as You Like // ///////////////////////////////////////////////////////// import java.lang.reflect.Method; import java.util.Arrays; import javax.swing.JOptionPane; public class BareBonesBrowserLaunch { private static final String errMsg = "Error attempting to launch web browser"; public static void openURL(String url) { String osName = System.getProperty("os.name"); try { if (osName.startsWith("Mac OS")) { Class fileMgr = Class.forName("com.apple.eio.FileManager"); Method openURL = fileMgr.getDeclaredMethod("openURL", new Class[] {String.class}); openURL.invoke(null, new Object[] {url}); } else if (osName.startsWith("Windows")) Runtime.getRuntime().exec("rundll32 url.dll,FileProtocolHandler " + url); else { //assume Unix or Linux String[] browsers = { "firefox", "opera", "konqueror", "epiphany", "mozilla", "netscape" }; String browser = null; for (int count = 0; count < browser ="="" browser =" browsers[count];" browser ="="">

view/download

Launch the user's default browser from your Java Swing application with the following line of code:

BareBonesBrowserLaunch.openURL(urlStr);

This is a fire and forget method -- no further communication or confirmation is provided. However, a pop-up error message will be displayed to the user in most cases if a failure is encountered.

MyApp Test Program

You can try out the cross-platform Bare Bones Browser Launch with this small standalone test program:

MyApp.java

import java.awt.event.*; import javax.swing.*; public class MyApp { public static void main(String[] args) { JFrame frame = new JFrame(); JPanel panel = new JPanel(); final JTextField urlField = new JTextField("http://www.centerkey.com "); JButton webButton = new JButton("Web Trip"); webButton.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent e) { BareBonesBrowserLaunch.openURL(urlField.getText().trim()); } } ); frame.setTitle("Bare Bones Browser Launch"); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); panel.add(new JLabel("URL:")); panel.add(urlField); panel.add(webButton); frame.getContentPane().add(panel); frame.pack(); frame.setVisible(true); } }

view/download

Tutorial

Put both the "BareBonesBrowserLaunch.java" and "MyApp.java" files into a folder, and issue the following command line instructions:

$ javac *.java
$ java MyApp

The first command compiles the two Java files into class files, and the second command runs the test program.

A window like the following will be displayed:

Click the "Web Trip" button to launch the default browser.

Of course, you'll need the Java JDK for this work, and you may also need to specify the full path to the Java commands. On Windows for example, the "javac" command above would become something like:

> "\Program Files\Java\jdk1.5.0_06\bin\javac" *.java

That's it.

JAR Library

Instead of putting the Bare Bones Browser Launch code directly in your project, you can alternatively use it as an external JAR library [file: BareBonesBrowserLaunch.jar, v1.5, 21KB] complete with source code and Javadoc. Tell your IDE, such as Eclipse or NetBeans, to include the JAR file into your project and then add the following "import" statement to the class responsible for opening a web page:

import com.centerkey.utils.BareBonesBrowserLaunch;

The code completion feature in most IDEs will automatically create the above "import" statement for you.

The steps for including an external JAR into your project will vary depending on your IDE. In Eclipse, open your project and navigate through these menus and options (screenshot):

Project → Properties → Java Build Path → Libraries → Add External JARs...

Now link to the Javadoc included within the JAR (screenshot):

Expand "BareBonesBrowserLaunch.jar" → Select "Javadoc location: (None)" → Edit... → Select "Javadoc in archive" → Browse... to BareBonesBrowserLaunch.jar → 2nd Browse... to doc

Finish the configuration process and you're ready to use the Bare Bones Browser Launch including the help activated with the F1 key.