java jee - Java Discussion Boards

Richard MacCutchan21-Nov-17 4:38

21-Nov-17 4:38

That seems like a lot of overkill just to learn Java; JDK 8 and Notepad is all you really need. Android studio is only required for building Android apps, and you need a solid grounding in Java before attempting it. Take a look at The Java™ Tutorials[^] where you can learn all you need.

Connection to server

Member 1351533210-Nov-17 23:42

Member 13515332

10-Nov-17 23:42

I want to send my html form data to the server(using servlet) using Json And retrieve the data from server and represent it in graph.
How can i do that,Please help me Am a fresher and i dont have any idea about server communication ,its urgent as i have to complete my project.

Re: Connection to server

Richard MacCutchan11-Nov-17 1:06

Richard MacCutchan

11-Nov-17 1:06

Member 13515332 wrote:
,its urgent

Member 13515332 wrote:
i dont have any idea

These two statements do not really fit together. You should have learned about server communication at the beginning of your project.

You need to be more specific about which parts of this you do not understand, and exactly what help you need.

Re: Connection to server

Member 1351533211-Nov-17 1:14

Member 13515332

11-Nov-17 1:14

Yeah

Please give me an idea about how to do it...So that i can learn For My Project.

Re: Connection to server

Member 1351533211-Nov-17 1:18

Member 13515332

11-Nov-17 1:18

I Have html form data that needs to be stored in server and fetch the data from server and represent it in graph. how can i do it.
please help me.

Re: Connection to server

Richard MacCutchan11-Nov-17 3:10

Richard MacCutchan

11-Nov-17 3:10

Sorry, but you are asking for a complete tutorial on communication between a client and web server; you cannot learn that in a few hours.

Re: Connection to server

jschell15-Nov-17 8:48

jschell

15-Nov-17 8:48

Member 13515332 wrote:
,its urgent as i have to complete my project.

I suspect you are out of luck then.

You have specified something that requires quite a bit of code and knowledge. Presumably you need to create both ends.

If you had time I would suggest that you learn one side first and use something simple like a hello world example. You can find examples of that by googling.

But either your class is poorly designed (teacher fault) or you haven't been keeping up (your fault) if this is the project and you have no idea how to do it.

java jee

Member 135124279-Nov-17 5:14

Member 13512427

9-Nov-17 5:14

Hello
I am a beginner in programming java jee, I am currently working on an application and I hangs the derapt how to establish a connection between eclipse and mysql 2014, I also ask if you have links and even book that explains how program with jee (jsf and primefaces also spring for security),

excuse me I do not speak well English

Re: java jee

Richard MacCutchan9-Nov-17 5:29

Richard MacCutchan

9-Nov-17 5:29

See The Java™ Tutorials[^]. Also, you do not want a connection between eclipse and mysql, but between your Java application and MySql. See the section in the tutorials on Data Bases. You can also find lots of useful information from Google.

Re: java jee

Member 135124279-Nov-17 5:57

Member 13512427

9-Nov-17 5:57

thank you for the information

Re: java jee

Manish K. Agarwal9-Nov-17 6:10

Manish K. Agarwal

9-Nov-17 6:10

Java Connectivity with MySQL[^]

Connect Java to a MySQL database[^]

Java Code using the List Interface not Compiling

BobInNJ8-Nov-17 11:14

BobInNJ

8-Nov-17 11:14

Please consider the following Java fragment where there are two classes defined: Tire and Radial. The class Radial has Tire has its super class. That is, Radial extends Tire.

    public static void addBrandTires(List<Radial> parts1, List<? extends Tire> parts2,
            String brand)
    {
        ListIterator<Radial> li = parts1.listIterator();
        while ( li.hasNext() ) {
            Radial t1 = li.next();
            if ( t1.getBrand().equals( brand) ) {
                parts2.add( t1 );
            }
        }
    }

The call to add generates the following compiler error:
error: no suitable method found for add(Radial)
parts2.add( t1 );
Since t1 is of type Radial, it is of type Tire therefore I expected it to work. I tired putting in a cast of t1 but that did not work either.

Bob

-- modified 8-Nov-17 16:23pm.

Re: Java Code using the List Interface not Compiling

Afzaal Ahmad Zeeshan8-Nov-17 14:47

Afzaal Ahmad Zeeshan

8-Nov-17 14:47

It might be that you are missing the fact that Java requires you to pass an index for the element to be inserted at as well.

Try this,

Java

// Inserts at location 0.
parts2.add(0, t1);

Also, if you need some other logic then implement that and change the "0" to a dynamic and controlled variable.
Java.util.ArrayList.add(int index, E elemen) Method Example

As to why you are facing this problem, read about the Capture Conversion, What is a capture conversion in Java and can anyone give me examples? - Stack Overflow
java - How can I add to List<? extends Number> data structures? - Stack Overflow

Lastly, it is much simpler to work with ArrayList<T> in Java as compared to working with List<T> in Java. ArrayList<T> would be much better alternative to your types in the code above. ArrayList<T> contains List<T> in the inheritance chain. See the documentation for more on that.
ArrayList (Java Platform SE 8 )

The sh*t I complain about
It's like there ain't a cloud in the sky and it's raining out - Eminem
~! Firewall !~

Re: Java Code using the List Interface not Compiling

Richard MacCutchan8-Nov-17 23:10

Richard MacCutchan

8-Nov-17 23:10

List (Java Platform SE 7 )[^].

Re: Java Code using the List Interface not Compiling

Afzaal Ahmad Zeeshan9-Nov-17 1:22

Afzaal Ahmad Zeeshan

9-Nov-17 1:22

Missed that casting requirement. Sigh | :sigh:

The sh*t I complain about
It's like there ain't a cloud in the sky and it's raining out - Eminem
~! Firewall !~

Re: Java Code using the List Interface not Compiling

Richard MacCutchan9-Nov-17 2:12

Richard MacCutchan

9-Nov-17 2:12

Probably the first time I've seen you make a mistake.

Re: Java Code using the List Interface not Compiling

Richard MacCutchan8-Nov-17 23:06

Richard MacCutchan

8-Nov-17 23:06

You cannot add a Radial object to a List of Tires, only a Tire object. If you were allowed to then you could start trying to call Radial methods, or access Radial properties on Tire objects, which is not possible.

Re: Java Code using the List Interface not Compiling

vishaljamdagni7-Feb-18 2:21

vishaljamdagni

7-Feb-18 2:21

Hey there, it seems like you're using the wildcard operator "?" and trying to use a method which is modifying the list at the same time.
Now I am no expert but I think the above combination cannot be used since if you want to add something to a generic collection then as far as I remember you have to use the "super" keyword with the wildcard operator to let the compiler stop bothering you from adding modifying your collection and with the keyword super you'll have to change the declaration to one hierarchical level lower as well.
Hope this helps, pardon me if I got it wrong though.
Cheers.

modified 8-Feb-18 1:11am.

Error Trapping this statement

Member 135080347-Nov-17 3:59

Member 13508034

7-Nov-17 3:59

I'm slowly learning Javascript, and am trying to error trap this statement to determine if the file exists. My webcam writes a snapshot every x amount of seconds and I want to try to display the latest snapshot. Synchronizing the time from camera to server, to user is impossible, so I want to run a loop to check for the latest file, then display it.

Anyway, error trap for this statement. That would throw an error if the file didn't exist
document.write('')

I played with the TRY function, but it didn't detect an error.

dsp

Re: Error Trapping this statement

Richard MacCutchan7-Nov-17 4:31

Richard MacCutchan

7-Nov-17 4:31

Member 13508034 wrote:
I'm slowly learning Javascript

Well the first thing you need to learn is that Javascript is not the same as Java.

Re: Error Trapping this statement

Member 135080347-Nov-17 6:28

Member 13508034

7-Nov-17 6:28

yea, figured that out, but still hoping there is a way.

Re: Error Trapping this statement

Richard MacCutchan7-Nov-17 7:56

Richard MacCutchan

7-Nov-17 7:56

And this still has nothing to do with Java. Please use the correct forum.

Re: Error Trapping this statement

Member 135080347-Nov-17 8:23

Member 13508034

7-Nov-17 8:23

apologies

Re: Error Trapping this statement

jschell8-Nov-17 8:29

jschell

8-Nov-17 8:29

Javascript forum

JavaScript Discussion Boards[^]

Re: Error Trapping this statement

ZurdoDev8-Nov-17 8:44

ZurdoDev

8-Nov-17 8:44

No, because JavaScript cannot access the hard drive so it won't be able to determine if the file exists or not.

There are two kinds of people in the world: those who can extrapolate from incomplete data.

There are only 10 types of people in the world, those who understand binary and those who don't.

Use Ctrl+Left/Right to switch messages, Ctrl+Up/Down to switch threads, Ctrl+Shift+Left/Right to switch pages.