I am a beginner and self learning web development for my personal interest, and I have a general question.
I developed a Dynamic Web application in eclipse which uses index.php (or .html ; I can choose) to make a call to javascript file, the JS file calls a java servlet for some optimization and internal calculations through AJAX call, and returns back data to JS and later to the HTML form on index.php. All the paths and mappings are done on web.xml file, and everything works perfectly! The project involves some external google libraries as well, which I have included in eclipse through Build Path.
Then I installed Wordpress locally through Xampp and copied all these files (including all the java classes and external JARs) keeping the folder structure same. Here, index.php does make the call to javascript file, but for AJAX call to java it shows me network error 404. So I have 2 questions:
Does the Wordpress doesn't accept mapping through web.xml? Should I only use absolute paths? I am avoiding absolute paths since I want flexibility in moving files around and I don't know how it will work online when I upload my project somewhere.
Or is the Wordpress/ Xampp not building/ compiling Java classes and external JARs somehow like it is done in Eclipse? I have no idea how this works! I did copy all the updated class files and stuff to the wordpress folders.
Please let me know how to proceed from here, or any suggestions in things I need to learn! I am keen to use Wordpress since it will save me lot of time in writing all the page codes for my website but the java file is also integral to it since it does lot of backend work. I saw lot of comments online that wordpress and java don't go together since it being a PHP based (I actually learned PHP due to this), but it works in eclipse using these 2 languages, so I am hopeful!! So any guidance will be really appreciated!
Thank you! :D
Anang
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As a project, I wanted to build a personal website using Java for the server-side code. I am very new to Java and wanted to know if it was possible to write Java using a simple text editor, upload the file into a file directory in Apache Tomcat where the corresponding JS and HTML file sits (for practice purposes only), and then run the web project through the HTML file.
I do this with php through LAMP all of the time, and was hoping Java might work that way as well.
Yes its very much possible. Even though you may find it bit difficult without the help of IDE, this should not make any difference. Convert the files to proper class files and upload it, that should do
Though i agree with above answer.But you can also go for hot deployment plugins for example mvn:jetty plugin for hot deployment of your website, but for that it needs to be maven project.Also grails and many other framework has this features inbuilt.
I've been doing some research into how to make Apple flat packages from a Java webapp. There doesn't seem to be much out on the subject. I found a website that details the contents of a flat package but it seems like a bit of a project to start from scratch. Anyone have any experience building PKGs? Does anyone know of any libraries to aid in the process?
EDIT:
It seems I may not have been clear in my request. My goal is to have users go to a website that requires them to enter some information. After they've entered their information my code would create a PKG for them that contains some information about them. For example, maybe the postinsall script would run the command "say 'Hello USERNAME_THEY_ENTERED'". Silly example but it's the general idea. The user would then be able to run the PKG and the install that takes place would be customized with their information.
Why would you want a web application in a pkg file? What servlet container accepts pkg files?
Web applications are meant to be packaged as WAR or EAR files (since we are talking about Java) and to be deployed on a servlet container like tomcat, jetty, websphere, glassfish, jboss, ... running on a server. The client computer then uses a browser to access to web application on the server.
PKG files can be compared to MSI files. These are meant to facilitate the installation of software (or libraries) on a client. For that the website you linked seems to have valid information.
I am not sure why you want to do that for a webapp but we have done it for a standalone Java App (which actually was a collection of webapps including the server).
If this works for you, try to prepare your application.app folder using jarBundler. It provides an Ant task that will make things much easier.
If this does not work for you (as unfortunately was the case for us), then you have to prepare the application.app folder by hand and script adding the java resources. Start from an existing app, generated with Jar Bundler for instance, and adjust accordingly.
Then you need to install XCode and get PackageMaker. This app has a GUI but you really need to read the doc. The biggest issue we have met is that you cannot script the package build process.
I need to add that, unless you need to run some post-install scripts, building a DMG is probably much easier.
Kind of hard to explain in one line but my problem is essentially like this:
I made a java applet that I want to run on a web page that I packaged into a .jar file. I'm able to get the applet working fine using the <applet> tag but the problem is, if the user views the page source, they will see:
<applet archive="directory/program.jar">
Assuming .jar files can be easily opened and all the class files decompiled, all the user would have to do is go to www.url.com/directory/program.jar to download my .jar and they would have all my source code :(
So I'm wondering if there is either a way to protect my code/jar from being decompiled (other than obfuscation) or to use some kind of server-side script to feed the contents of the .jar directly to the browser from a server-side location not publically visible.
Any help is appreciated.
This is fundamentally impossible.
Java applets run the client.
Anything that runs on the client can be disassembled and modified by a sufficiently advanced user.
You should move your sensitive logic to the server and invoke it using HTTP requests ( and remember that the user can use Fiddler).
While you're at it, you should probably replace your applet with HTML and Javascript.
Other than obfuscation or encryption, no--one way or the other, the browser will have access to the jar.
You might be able to create an applet that loads more functionality at runtime.
There is no effective way to block access to the source code of any page; for the page to be readable by browsers and search engines, the source code has to be accessible, and therefore can be viewed and/or copied. That's just how the web works. HTML is sent as a text document and interpreted client-side.
Disabling the right-click is little more than an annoyance, and it works sporadically in alternative browsers. Even if you succeed, the View Source option in the menu is always present. The viewer could also use a download tool such as Wget, or even get the page from the Google cache without visiting your site at all.
Edit: Oops! I misunderstood your question. You should follow #SLaks advice and "move your sensitive logic to the server and invoke ot using HTTP requests ( and remember that the user can use Fiddler)."
While quantum mechanics do rule the universe, they have less of a grip on your code than you might suspect. You cannot both deploy code to the client browser and not deploy code to the client browser. You have the option of doing one or the other.
You can prevent direct browsing to your .jar file by locating it beneath the WEB-INF directory in your WAR file. This will also prevent <applet archive="directory/program.jar"> from working.
Once the jar is beneath the WEB-INF directory you will need something to feed the resource to the client browser; the Spring resources servlet is good for this (If you are using Java and Spring). I feel confident that other such tools exist. With the Sprint resours servlet, your would deploy your applet with something like this: <applet archive="resource/program.jar".
If you write your own resource distributor, you can add security to make it harder to get the jar file; perhaps add a header to your requests like IRGud: <user_id here> and fail any request that does not have that header (or acceptable contents in the header).
I just needed to create a little interface for a project. So I decided to take given code and to run it on Google AppEngine. My problem is, that I'm experienced in JavaScript and got some basic knowledge of Java, but I got no clue how a Java webapp has to be structured. I started Eclipse and installed the AppEngine-addon, downloaded Rhino and env.js (which is necessary for the bunch of code I need to run) but then found me in the situation of sitting on this files not knowing where to put them.
It would be great if someone could tell me in which directory to put which files for Rhino (I assume it's "/war/WEB-INF/lib/"), how to add the env.js-file and how to access all these files inside the .java-file which is the index of the app.
I don't know about app engine in particular, but I have had good success using Rhino jsc to compile script files which extend the Servlet API. The end result is a nice WAR file which you can deploy in any servlet container, and perhaps App Engine as well. See here for my relevant blog post about this technique, and here for a sample Eclipse project.
Have you taken a look at this tutorial on running Rhino on GAE?
It's a link from the official "Will it play in App Engine?" thread.
http://www.appenginejs.org/ may be of interest as well.
so now i think i have learned all basics and terminology for java. but what i don´t know is how to code and display a web page with Netbeans in Java.
the most tutorials contains lots of talks about different technologies "Java uses Java Beans, JSP and servlets" and so on. Where can i find short practical tutorials that actually teach me where to code what and then compile and where to put all the files (war, jar, ear..) in Glassfish to be able to see the output from a Web browser. Simples things that makes one understand all these different "layers" which are just classes using classes. Feels like i never get to know how i can put up a web server with Java cause I can´t find this kind of tutorials.
Would be great if someone could send some links to such practical stuff.
Thanks.
This is the first such document I found: http://www.java-tips.org/java-tutorials/tutorials/introduction-to-java-servlets-with-netbeans.html
More:
http://netbeans.org/kb/docs/web/quickstart-webapps.html
http://blogs.oracle.com/jonasdias/entry/webservices_with_jsp_on_netbeans
http://www.fuzzylizard.com/archives/2005/09/18/628/
http://cit.wta.swin.edu.au/cit/subjects/CITP0014/tutorials/netbeans/tomcat/Running_Tomcat_from_Netbeans.html
http://supportweb.cs.bham.ac.uk/documentation/java/servlets/netbeans-webapps/
I even found a small ebook on this (PDF!) http://www.comp.dit.ie/bduggan/Courses/projects/Getting%20Started%20with%20Tomcat%20&%20NetBeans.pdf
How do I code and display a web page with NetBeans in Java?
Let's go! Fire up NetBeans. I'm using NetBeans 6.7.1 with the Java EE stuff installed, and I've got a GlassFish installed and tied up, so I don't have to care about that stuff. Your setup might differ in the details.
Do a File->New Project, and pick "Java Web" from the categories. Select "Web Application" and hit Next. Enter a project name and tweak the location, if liked. Hit Next. The next page should have a server selection drop-down; as hinted above, mine has "GlassFIsh v2.1" selected. That's fine - as long as NetBeans can interact with a Java application server of some sort, this crash course will run okay.
Make a note of the "context path" - this will be based on the project name, and basically forms the base of the URL at which your application will reside. Hit Next. Ignore the next page, for now, which talks about various frameworks, and hit Finish.
Churn, churn. You should eventually see your web project created. It's a very simple application which contains a single JSP file, and that will be open in the main editor. It's got a bunch of HTML in it, and some JSP syntax.
Take a look at the project structure. You've got a "web pages" folder which contains a WEB-INF directory, and an index.jsp file. That's the same file you're looking at. WEB-INF is a standard directory which contains the metadata used to deploy your application, and also the compiled classes that power it.
The only thing you should need to do now, in order to get to the original objective, is to hit the big ol' Run button, or right-click on the project and select "Run" from the menu. NetBeans will compile, and then fire up your application server and deploy the application to it. Finally, your web browser should pop open a new tab with the classic "Hello, world" page in it.
At this point, what do you actually have? You've got an empty web project with a single JSP file in it. You could customise it, but that's maybe not very exciting. What you're really looking at is a basic framework in which you can apply your learning of JSP and of servlets as you get to grips with them.
How to proceed with said knowledge transfer? I recommend a decent book or two. The one I used to get going was "Beginning JSP, JSF and Tomcat Web Development: From Novice to Professional" (Zambon, Guilio; Apress; ISBN 1-59059-904-7), which has a decent beginner's guide to how JSP and servlets work together, and a handy reference guide for the former.
As soon as possible, you're going to want to migrate away from raw servlets and JSP to tying them together in a slightly more flexible way using one of the frameworks I skipped over earlier. I'm not going to tell you which one to learn; there are several pretty decent ones. Try Spring MVC, or Struts. Once again, I'd suggest getting a decent book.
I would start by taking a look at servlets and JSP. I found this book helpful when I read it: Head First Servlets and JSP
Netbeans comes with many sample projects, create a few and browse the source code.
A already working sample is always a good starting-point for your coding.
If you're also interested in using Eclipse, which makes it very simple to create and deploy web applications here's a nice tutorial - WTP Tutorials
Hi to start code and setting up web server with java follow the following procedure.
First you need to install Apache-Tomcat or Jetty any web container or servlet container.
And you have set the classpath of servlet-api.jar file.
Next you will have to save your web-page code stuff in web-apps folder of tomcat.In web-apps folder there you have to create a web-inf folder in which web.xml file is stored.And after writing servlet and jsp programs the compiled class files are stored in classes folder of web-inf folder.JSP files are stored along with WEB-INF folder.
You have to keep all the jar files in LIB folder of classes folder.
The web container will take care of initalizing servlet, loading class using inti method.Using service method it will create two objects request and response.
The Java EE stack is quite a mouthful. I suggest you just look at writing a Web Application (WAR), and deploy it to Tomcat.
Unfortunately doing a full WAR-file deployment is rather tedious so you generally want some help from your IDE or the web container.
The easiest place to start is probably installing and starting Tomcat and then fiddle with the files in the file system. There is an example application.