How to use processing sketch in a web app - java

Good day, i have a Processing sketch that i want to use in a web application
i am using jsp and servlets in my web app with tomcat as a server. I am using netbeans and i tried using < applet > tag but i can't get it to work, please help.
CODE:
import processing.core.*;
public class MyProcessingSketch extends PApplet {
public static void main(String args[]) {
PApplet.main(new String[] { "MyProcessingSketch" });
}
public void setup() {
}
#Override
public void draw() {
background (200,0,0);
}
public void settings(){
size(600,240);
}
public void mousePressed(){
exit();
}
}

Applets are not really supported anymore... But you might try p5js. Your HTML page would look like this:
<html>
<script src="http://cdnjs.cloudflare.com/ajax/libs/p5.js/0.4.6/p5.js"></script>
<script>
function setup() {
createCanvas(600, 240);
background(200,0,0);
}
function draw() {
// ...
}
</script>

Like the other answer says, applets are pretty much dead. They currently require you to have a paid signed certificate or for your users to change their security settings. And even then they show a bunch of scary warning dialogs, and it's just a pain in the neck for everybody. Chrome has dropped support for applets, and they'll be deprecated in the next version of Java.
If you're using eclipse, you've got three options:
Deploy as a runnable jar.
Deploy as a packaged executable.
Deploy using webstart.
None of these are embedding an applet in a webpage.
However, if you're using the Processing editor, you can use Processing.js to write the same Processing code but have it deployed as JavaScript, which you can embed in a webpage. Processing.js does the translation for you, so you don't have to change your code into JavaScript code.
You can also use p5.js, but that will require you to completely rewrite your syntax into JavaScript syntax.
In either case, you'll no longer be able to use Java libraries in your code. You'll have to find a JavaScript library that does the same things and use that instead. If you really need to use the Java libraries, then you have to go with deploying using one of the first three options.

Related

Get a copy of the source code that the user sees

I search the web for hours, but could not find a helpful direction.
I need to use Java to create a code that "catches" the source code
that the user is asking from the browser.
The application: (the basic idea)
public static void main(String[] args) {
String sourceCode;
initialize();
start();
waitingForSourceCode();
sourceCode = catchingTheSourceCode();
System.out.println(sourceCode);
}
Behind the scenes:
the application "catches" the source code of the web page.
And print it to console.
How to implement these methods?
waitingForSourceCode();
catchingTheSourceCode();
If you are using a WebDriver, you can get the page source using the getPageSource() method:
catchingTheSourceCode(){
System.out.println(driver.getPageSource());
}

Input to JavaFX from JSP

I want to give dynamic input to Java FX application from a JSP page. I am not able to find any suitable way.
Dynamic in the sense that I want to give input to JavaFX application based on user input in a JSP page. I am embedding the same Java FX application in the same JSP page.
Any help is welcome regarding the same.
I want to give input to Java FX application when it is running through JSP page.
See the JavaFX deployment topic: Accessing a JavaFX Application from a Web Page.
The JavaScript => JavaFX interface in JavaFX is the same as that used for a traditional Java applet - it makes use of a technology known as LiveConnect. Further documentation on using LiveConnect is in the LiveConnect documentation topic: Calling from JavaScript to Java.
The JavaFX documentation provides the following sample code:
Java Code
package testapp;
public class MapApp extends Application {
public static int ZOOM_STREET = 10;
public static class City {
public City(String name) {...}
...
}
public int currentZipCode;
public void navigateTo(City location, int zoomLevel) {...}
....
}
JavaScript Code
function navigateTo(cityName) {
//Assumes that the Ant task uses "myMapApp" as id for this application
var mapApp = document.getElementById("myMapApp");
if (mapApp != null) {
//City is nested class. Therefore classname uses $ char
var city = new mapApp.Packages.testapp.MapApp$City(cityName);
mapApp.navigateTo(city, mapApp.Packages.testapp.MapApp.ZOOM_STREET);
return mapApp.currentZipCode;
}
return "unknown";
}
window.alert("Area zip: " + navigateTo("San Francisco"));
Note the important comment in the JavaScript code "Assumes that the Ant task uses "myMapApp" as id for this application". The id referred to is the placeholderid parameter of the fx:deploy task.
Now, because you are using a JSP, presumably the html page containing the application is dynamically generated by the JSP processor. So, what you may want to do is make use of the fx:template task to generate modified jsp source which invokes the dtjava deployment script to embed your target JavaFX application.
I'm not sure, but try: HostServices.getWebContext

Call java method in javascript without html firebug extension

I'm trying to develop an extension for firebug. I want to call a java method in this extension but there is no html in it so I can't use the applet-html solution.
Here is my java Applet :
import java.applet.Applet;
import javax.swing.JOptionPane;
public class MyApplet extends Applet {
public void init() {
super.init();
System.out.println("init something");
}
public String jsCall(String hello) {
System.out.println("this method is called by a js function and say :"
+ hello);
Thread t = new Thread(new Runnable(){
public void run(){
JOptionPane jop1 = new JOptionPane();
jop1.showMessageDialog(null, "Message informatif", "Information", JOptionPane.INFORMATION_MESSAGE);
}
});
t.start();
return "lala";
}
}
I try this:
var applet = document.createElement("applet");
applet.setAttribute("code","file:///home/dacostam/z_test/firebug-extension-examples-0bdcf15/helloamd#janodvarko.cz/chrome/content/MyApplet.class");
applet.setAttribute("id","javaToJavascriptApplet");
applet.setAttribute("mayscript","true");
applet.jsCall("HelloWorld"); //jsCall not a function
And this:
var dom = document.implementation.createDocument('http://www.w3.org/1999/xhtml', 'html', null);
dom.appendChild(applet);
dom.javaToJavascriptApplet.jsCall("HelloWorld"); //jsCall not a function
The document is not like usual there is no body or html in it.
Is there an other way to call java in javascript instead of the applet-html solution?
Or is there a way to do it with this method but otherwise?
If you need more information, I'm here.
Thanks.
Edit:
It would be to long to explain you what the program do, just keep in mind that it's inevitably in java, I just need to call a method which take a parameter string and return a string or eventually void.
Edit2:
Sorry I have not thought of that, java needs to run on the client.
If your requirement is to make a call from JavaScript to your Java application, you need to clarify where does your Java app needs to run.
If Java needs to run on the client (same machine as your Firebug), it looks like you are either stuck with an applet or you need to be building a tiny webservice in your Java so you can talk to it through a web API on localhost.
If your Java can sit on a server somewhere, you could talk to your Java application through a web API (similarly to the second option above).

Java Applet/Web Browser Issue

I am new to Java (and programming in general) so I thought that making a simple test case applet would help to form a basic understanding of the language.
So, I decided to make a basic applet that would display a green rectangle. The code looks like:
import javax.swing.JApplet;
import java.awt.Color;
import java.awt.Graphics;
public class Box extends JApplet{
public void paint(Graphics page){
page.setColor(Color.green);
page.fillRect(0,150,400,50);
}
}
The HTML file (test.html) that I then embedded that into looks like:
<html>
<body>
<applet code="Box", height="200" width="400">
</applet>
</body>
</html>
I then compiled/saved the Java bit, and put the two into the same folder. However, when I attempt to view the html file, all I see is an "Error. Click for details" box. I tested this in both the most current version of Fire Fox and Opera, and too did I make sure that the Java plug-in was enabled and up to date for both.
So what exactly am I forgetting to do here?
It seems as if everything is close to OK.
Once the .class file is in the same folder as your HTML file it should come up. Your code might contain a typos (comma after "Box").
Example :
<Applet Code="MyApplet.class" width=200 Height=100>
See also :
http://www.echoecho.com/applets01.htm
#Juser1167589 I hope your not still having issues with this, but if you are, try going into your program files, delete the JAVA folder, then redownload java from the big red button on 'java.com'. If there is no JAVA folder then * FACEPALM * GO DOWNLOAD JAVA. another possible answer to why you were seeing the errors on the other sites is that they might not have the required resources to run it anymore.
Applets are not a good place to start.
They are a very old technology and really not very widely used compared to other parts of the Java technology stack.
If you're new to programming in general, I really wouldn't start with applets.
Instead, you should try learning basic programming and Java by building some simple console apps. I've added some general comments about how to do this. After your confidence rises, you can then start worrying about adding extra complexity, applets etc.
First of all download an IDE. Eclipse is one obvious choice (there are also NetBeans and IntelliJ). All modern developers work within an IDE - don't be tempted to try to muddle through without one.
Then, you should have a "scratchpad" - a class where you can try out some simple language features. Here's one which might be useful:
package scratch.misc;
public class ScratchImpl {
private static ScratchImpl instance = null;
// Constructor
public ScratchImpl() {
super();
}
/*
* This is where your actual code will go
*/
private void run() {
}
/**
* #param args
*/
public static void main(String[] args) {
instance = new ScratchImpl();
instance.run();
}
}
To use this, save this as a .java file. It can be a template for other simple experiments with Java. If you want to experiment with a language feature (inheritance, or polymorphism, or collections or whatever you want to learn) - then copy the template (use the copy and rename features inside your IDE, rather than manually copying the file and changing the type names) to a new name for your experiment.
You may also find some of my answer here to be useful.

How can I fill out an online form with Java?

My cell phone provider offers a limited number of free text messages on their website. I frequently use the service although I hate constantly having a tab open in my browser.
Does anyone know/point me in the right direction of how I could create a jar file/command line utility so I can fill out the appropriate forms on the site. I've always wanted to code up a project like this in Java, just in case anyone asks why I'm not using something else.
Kind Regards,
Lar
Try with Webdriver from Google or Selenium.
Sounds like you need a framework designed for doing functional testing. These act as browsers and can navigate web sites for testing and automation. You don't need the testing functionality, but it would still serve your needs.
Try HtmlUnit, or LiFT, which is a higher-level abstraction built on HtmlUnit.
Use Watij with the Eclipse IDE. When your done, compile as an .exe or run with a batch file.
Here is some sample code I wrote for filling in fields for a Google search, which can be adjusted for the web form you want to control :
package goog;
import junit.framework.TestCase;
import watij.runtime.ie.IE;
import static watij.finders.SymbolFactory.*;
public class GTestCases extends TestCase {
private static watij.runtime.ie.IE activeIE_m;
public static IE attachToIE(String url) throws Exception {
if (activeIE_m==null)
{
activeIE_m = new IE();
activeIE_m.start(url);
} else {
activeIE_m.goTo(url);
}
activeIE_m.bringToFront();
return (activeIE_m);
}
public static String getActiveUrl () throws Exception {
String currUrl = activeIE_m.url().toString();
return currUrl;
}
public void testGoogleLogin() throws Exception {
IE ie = attachToIE("http://google.com");
if ( ie.containsText("/Sign in/") ) {
ie.div(id,"guser").link(0).click();
if ( ie.containsText("Sign in with your") ||
ie.containsText("Sign in to iGoogle with your")) {
ie.textField(name,"Email").set("test#gmail.com");
ie.textField(name,"Passwd").set("test");
if ( ie.checkbox(name,"PersistentCookie").checked() ){
ie.checkbox(name,"PersistentCookie").click();
}
ie.button(name,"signIn").click();
}
}
System.out.println("Login finished.");
}
public void testGoogleSearch() throws Exception {
//IE ie = attachToIE( getActiveUrl() );
IE ie = attachToIE( "http://www.google.com/advanced_search?hl=en" );
ie.div(id,"opt-handle").click();
ie.textField(name,"as_q").set("Watij");
ie.selectList(name,"lr").select("English");
ie.button(value,"Advanced Search").click();
System.out.println("Search finished.");
}
public void testGoogleResult() throws Exception {
IE ie = attachToIE( getActiveUrl() );
ie.link(href,"http://groups.google.com/group/watij").click();
System.out.println("Followed link.");
}
}
It depends on how they are sending the form information.
If they are using a simple GET request, all you need to do is fill in the appropriate url parameters.
Otherwise you will need to post the form information to the target page.
You could use Watij, which provides a Java/COM interface onto Internet Explorer. Then write a small amount of Java code to navigate the form, insert values and submit.
Alternatively, if it's simple, then check out HttpClient, which is a simple Java HTTP client API.
Whatever you do, watch out that you don't contravene your terms of service (easy during testing - perhaps you should work against a mock interface initially?)
WebTest is yet another webapp testing framework that may be easier to use than the alternatives cited by others.
Check out the Apache Commons Net Package. There you can send a POSt request to a page. This is quite low level but may do what you want (if not you might check out the functional testing suites but it is probably not as easy to dig into).
As jjnguy says, you'll need to dissect the form to find out all the parameters.
With them you can form your own request using Apache's HTTP Client and fire it off.

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