Handling CSS and JavaScript when building a Java browser - java

My task is to create a simple web browser in Java.
So far it can only read HTML pages.
I'm using standard JEditorPane component to display webpages.
Now I was wondering is there any way you could explain me how can I manage to display at least some simple pages that contain CSS/Javascript.
If you could point me to some useful links or appropriate examples I would be very happy.

Well, my advice would be to look at open source rendering engines such as Gecko - https://developer.mozilla.org/en/Gecko_FAQ
You can embed Gecko with Java using the JREX library - http://jrex.mozdev.org/
Starting from scratch with a problem like this is a very big task, and as your username is AmateurProgrammer, I wouldn't recommend it.

There alrady is some prior art for the Java browser segment.
concerning javascript, you will have to use a javascript interpreter in Java. A renowned one is Rhino (by Mozilla). Its integration may reveals to be an interesting challenge.
concerning CSS, it seems the question has already been asked ...

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prerequisites for developing a web browser in java [duplicate]

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How to get started building a web browser?
I have a basic understanding of the Java language and also some knowledge about applets.
I have to develop a basic Web Browser for my college project which can display simple websites along with Javascript components.
Could anyone tell me what are the prerequisites i.e, what topics should I read before doing this and how to do it?
Really appreciate the help
Writing a web browser is a major undertaking, depending on the level of functionality you want to include.
Things that need to go into a browser:
An HTTP client that can retrieve the page content from a server. Java includes something very basic inside java.net, but if you can, use the Apache Commons HTTPClient instead. Many browsers also have support for other protocols, such as ftp:// or local files (file://).
An HTML parser, which can read the returned HTML (or XHTML) into an in-memory structure. The hard part here is that not only has HTML evolved; there is also a lot of HTML out there that does not conform to any of the multiple HTML standards. People just tend to write something, see if it can be rendered on a specific browser (say, IE), and move on -- and certain browsers can render almost anything. You can use existing parser such as JSoup for this, which also has limited support for fixing mistakes.
A rendering engine. This would be, for me, the most complex step. You would need really in-depth reading to get any sort of CSS support working (major browsers had a hard time getting it right too), and even non-css rendering such as nested tables or complex forms would imply hard work (to calculate where each page component goes on the rendered page). There are no add-on rendering libraries that I know of, but there is minimal (HTML 3.2?) HTML rendering support inside the JEditorPane - you may be able to use that (forget about advanced CSS, thouth).
Scripting support. This would interpret JavaScript, and make your pages interactive. You can use Rhino for that (maintained by the folks at Mozilla, and very powerful).
(Plus internal caching to avoid making repeated requests; support for saving pages to files; support for 3rd party plugins/extensions such as Flash; security considerations to avoid cross-site scripting attacks on your users ... there are many more components or concerns that I have not bothered to include above).
Since you have only basic understanding of Java, and any of the above components are fairly complex projects in their own right, I would suggest choosing another project or delimiting a very small subset of what a commercial web browser does to try to implement that instead.

UIWebView-style Java component

I'm new to Java and Java Swing, and I'm creating an application that requires the presentation of web pages. I program for iOS a lot, and the simple solution here would be to load the page in a UIWebView. Is there an easy component for Java Swing? Or, is there an easy way to create something of the sort either in or outside of Swing?
I'm basically looking for something where you put in a URL, and a page loads in the application that looks like a normal page in a web browser.
If your Java program is a desktop application, the browse() method of java.awt.Desktop accepts a URI that may be obtained form a URL. The feature was added in Java SE 6. It's not embedded, but the user's chosen browser may be more appealing.
Addendum: See also How to open a URL in the default browser.
There's no single useful solution. There is the JEditorPane class, but it supports only HTML 4 and my experience with it is awful. For example, HTML comments showed up as plain-text.
If, however, you broaden the search to something outside Swing, there are plenty components that will do the job well. See this related question for a detailed discussion of these.

A java program to search in a certain website

I want to write a Java code to parse a certain website. Each result in the website appear in a specified URL.
How can I start? Is there a good library to use? Could I benefit from your experience in this field?
Search for "web crawler" and you'll find many examples (e.g. Crawler4J or Crawler), how to solve this.
Besides Java, you'll often stumple upon Python when it comes to grepping stuff from web pages - I'm not a Python guy, but it seems to fit for the task.

Using java to create a web browser

Is it possible to use Java to build a web browser like Internet Explorer that will open all the web pages and display all the contents?
The only valid answer to that question is:
Yes, it's possible to use Java to build a web browser.
However, a web browser is an exceptionally complex piece of software. Even Google, when building its Google Chrome browser, used existing technology to do it, rather than inventing their own browser from scratch.
If your goal is anything other than building and marketing your own browser, you may want to reconsider what exactly you want to accomplish, in order to find a more direct approach.
I advise you to take a look at the Lobo Browser project, an open-source java-written web browser. Take a look at the source and see how they did it.
Yes, it is possible. JWebPane is a work in progress migration of Webkit. It is supposed to be included in JDK7 but I wouldn't hold my breath.
JWebPane browser = new JWebPane();
new JFrame("Browser").add(browser);
browser.load(someURL);
Yes, it's possible, and here's what you would need to start looking at.
First, search for an HTML renderer in Java. An example would be JWebEngine. You can start by manually downloading HTML pages and verifying that you can view them.
Second, you need to handle the networking piece. Read a tutorial on sockets, or use an HTTP Client such as the Apache HTTPClient project.
Edit:
Just to add one more thought, you should be honest with yourself about why you would work on this project. If it's to rebuild IE, FF, that is unrealistic. However, what you might get out of it is learning what the major issues are with browser development, and that may be worthwhile.
Take a look at the JEditorPane class. It can be used to render HTML pages and could form the basis of a simple browser.
Yes. One of the projects in Java After Hours shows you how to build a simple web browser. It's not nearly as full-featured as IE or Firefox of course (it's only one chapter in the book), but it will show you how to get started.
The hardest thing will be the rendering component. Java7 will include JWebPane, that internally uses WebKit. Here you can find some screenshots.
I develop this browser for my college project may be this helpful for you
My Button is open source java web browser.
Develop for school and college projects and learning purpose.
Download source code extract .zip file and copy “mybutton” folder from “parser\mybutton” to C:\
Import project “omtMyButton” in eclipse.
Require Java 6.
Download .exe and source code :
https://sourceforge.net/projects/omtmybutton/files/

How can a java library be ported to the web?

How do you take a java library that is for the desktop or an applet and make it so you can use its functions for a web page? I know not all things are meant for the web, but can you call a "regular" java class in an apache/tomcat setup server and it "work"? Do you have to so something to it to get it work with a web page?
I was interested in jgrapht for the web but it looks like all desktop or applet and I don't know that it would be possible to return its graphics to the browser, but maybe its libraries and a generated .png rendered by the browser.
Although there is debate on applets being alive or dead, I am not interested in using one at the moment, as it appears it is dead, albeit with new possible life in the latest update 6u10. I don't know that I want to invest in JavaFX either.
Johnny, the thing is that you have to decide what you mean to do. You could, for example, use JGraphT in server side code; the graph could be visualized in a bunch of different ways, like JGaph or graphviz. Then you would output the visualization in some form that works on the web and put it into your web page. In JGraph, that probably means a print interface that generates SVG or PNG.
Or you could emit the graph structure as JSON with a simple walk of the graph and interpret it on the fly in the browser using Javascript.
It's hard to answer the question generally, because it strongly depends on how you mean to use it.
Yes, it is possible to use a java class or jar file in a web appliaction, but it also depends on what you want to do with it.
For example if the library is for mathematics and you want to return results back to the users on a web based application, this is definitely possible. There are many other examples I can give but they are all the same.
As for displaying charts, I have successfully used JFreeChart in a web application using Apache Wicket (which rocks btw).
So to answer your question, you don't really need to "port" the library, you just need to use it and display it's output to a web page instead of a java desktop GUI.
Of course their might be some libraries that are specifically designed for Java GUI stuff like Swing or AWT. But for the most part there is no difference in using a Java library in a J2EE environment or a J2SE environment.
There isn't a closed-form answer to what you are suggesting: porting a Java Library to a browser's environment and using its functionality.
If you are interested in graphing things, here are a few things you can try:
Open Flash Chart - a scriptable flash app that will produce graphs
Bluff - a Javascript library that produces graphs
processing.js - a port of the excelling 'processing' library to Javascript
As for accessing Java-based functionality in the browser, there are some approaches for that. One is to use a toolset like GWT that complies java into an HTML/Javascript/Java application. Another is to use an AJAX-based technology like Direct Web Remoting. It really depends on what you are trying to accomplish.

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