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I really don't understand, this is currently beyond me at the moment.
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Well, object oriented programming is not easy at first. Socket/network programming is also hard. Threading is another beast. And you are mixing all of these, are you sure this is what you wanna do?
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I'm committed to learn it and since I'm self taught, I've decided to throw myself in and learn how it all works then learn in more depth.
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I don't recommend doing so, but good luck!
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how to make session in beanshell ??
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Please try a better title, and a clearer question. You should first try typing this question into Google to see what you get.
One of these days I'm going to think of a really clever signature.
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jsp里边有一个内置的对象叫做session，不需要创建直接用就行，调用方法比如session.setAttribute("name","value");
you needn't create but it exeists.
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Hi,
i have a main webpage with this code
<input type="button" value="Maak een bord positie code" onClick="window.open('makeboard.html','makeposition',' width=500,height=700');">
my form is, i think well formed
<form name="post" action="add.php" method="post" name="myform" id="myform"> and also closed
On the child form I have some code
var pa=parent.document.getElementById('myform')
However the var pa is empty.
has someone an idee what is wrong?
Jan
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Are you sure this is java? Looks more like javascript.
Panic, Chaos, Destruction. My work here is done.
Drink. Get drunk. Fall over - P O'H
OK, I will win to day or my name isn't Ethel Crudacre! - DD Ethel Crudacre
I cannot live by bread alone. Bacon and ketchup are needed as well. - Trollslayer
Have a bit more patience with newbies. Of course some of them act dumb - they're often *students*, for heaven's sake - Terry Pratchett
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Your right. It's javascript. I didn't know there is another forum for javascript. However I found it after days of looking I posted the question and today I found that I must use 'window.opener.document'
Jan
PS: If there is an admin he/she may move the message to the correct forum 
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Okay. The admins may or may not move this, it depends on getting them sober enough for long enough. 
BTW, I did not 1 vote your question, I will counter it as it is not deserved.
Panic, Chaos, Destruction. My work here is done.
Drink. Get drunk. Fall over - P O'H
OK, I will win to day or my name isn't Ethel Crudacre! - DD Ethel Crudacre
I cannot live by bread alone. Bacon and ketchup are needed as well. - Trollslayer
Have a bit more patience with newbies. Of course some of them act dumb - they're often *students*, for heaven's sake - Terry Pratchett
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hello
I wanna make session between two field in code .bsh (BeanShell) : is sample java code
Internet pages contain the same field Example: Field Name
When entering values in the first field in the first page and move on to the second page must be entered the same values found in the other the right
please i want that code ???
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I want the code to generate everything I need for the project I'm working on, but that doesn't mean I'll get it.
Try to rephrase the question as a first step to make it clearer (I don't understand very much of what you're asking to be honest). And as a second step, try at least to come up with a solution all by yourself, post what you've come up with, and where you got stuck. People will try to help you, but only if you show that you're willing to help yourself.
In the current form of your question, you're highly unlikely to get an answer.
Full-fledged Java/.NET lover, full-fledged PHP hater.
Full-fledged Google/Microsoft lover, full-fledged Apple hater.
Full-fledged Skype lover, full-fledged YM hater.
modified 2-Aug-12 7:03am.
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Hai,can any one help me in this querry.
I am calling a function 'A' which is in a class 'CA', from a function 'B' which is in the Class 'CB'.If there is any exception produced in function 'A' it will generate an error code(intiger Value)in Catch block.How can i get that error code from the Function A to function B only if the exception had occured.
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If the error code generated by method A on exception is unique (meaning that no normal output from A will ever match that error code), you can simply do this (assuming that error code returned on exception is -1):
if(ca.A() == -1) {
}
Conversely, if you have access to the sources and you are allowed to modify them, don't catch the exception. Modify the CA.A() method signature and add throws ExceptionThrownFromCA (just an example). Like this, you don't even need to check the error code, and you can do this:
public void B() {
CA ca = new CA();
try {
ca.A();
} catch(ExceptionThrownFromCA e) {
}
}
Full-fledged Java/.NET lover, full-fledged PHP hater.
Full-fledged Google/Microsoft lover, full-fledged Apple hater.
Full-fledged Skype lover, full-fledged YM hater.
modified 1-Aug-12 10:07am.
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Further to the earlier answer:
0. There are no functions. In the OO world, an object supports methods and, in some cases but not Java, properties.
1. If a class throws an exception it must declare it in it's signature:
void methodName() throws MethodException {
...
}
2. An exception is not an error. An exception should be used when you don't know what to do or cannot continue processing. As an example, if you insert a row into a table and it violates a unique constraint then that is an exception. If you try to read a value from a table and it does not exist that is an error.
3. It is advisable to not use an exception to pass results. The choice should be that if an exception is thrown the calling method defaults a result or the called method's return values must include an error range.
Panic, Chaos, Destruction. My work here is done.
Drink. Get drunk. Fall over - P O'H
OK, I will win to day or my name isn't Ethel Crudacre! - DD Ethel Crudacre
I cannot live by bread alone. Bacon and ketchup are needed as well. - Trollslayer
Have a bit more patience with newbies. Of course some of them act dumb - they're often *students*, for heaven's sake - Terry Pratchett
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Thankyou for your reply .
So what you suggest to do for the above case
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I do not have your code so I cannot possibly say which way is better, that is up to the implementation. If the called method knows what to do irrespective of the caller then the exception should not be thrown up the stack.
Panic, Chaos, Destruction. My work here is done.
Drink. Get drunk. Fall over - P O'H
OK, I will win to day or my name isn't Ethel Crudacre! - DD Ethel Crudacre
I cannot live by bread alone. Bacon and ketchup are needed as well. - Trollslayer
Have a bit more patience with newbies. Of course some of them act dumb - they're often *students*, for heaven's sake - Terry Pratchett
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Can i make that error code variable as global and when ever i am calling any fuction after that itself i will access the error code and check it.
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There is no such thing as 'global' in java.
One approach is to have an error state within a class, but this may not be appropriate. I would suggest that if you need to have a return code AND an exception then you can always return a composite class:
public class ReturnState {
private final int code;
private final String description;
private final Object object;
private final Exception exception;
public ReturnState (int code,
String description,
Object object,
Exception exception) {
this.code = code;
this.description = description;
this.object = object;
this.exception = exception;
}
public int getCode() {
return this.code;
}
public Exception getException() {
return this.exception;
}
...
}
That said, it is rare that you need BOTH so either have the return codes include errors or use exceptions.
Panic, Chaos, Destruction. My work here is done.
Drink. Get drunk. Fall over - P O'H
OK, I will win to day or my name isn't Ethel Crudacre! - DD Ethel Crudacre
I cannot live by bread alone. Bacon and ketchup are needed as well. - Trollslayer
Have a bit more patience with newbies. Of course some of them act dumb - they're often *students*, for heaven's sake - Terry Pratchett
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k
Got it thanks a lot, i will return the exception,according to the exception i will generate the error code in my calling function.
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I work with jee and JSF2.0 and hibernate
I want to access my data in my xhtml page my data are stored in hashset in the managedBean
I don't find how to access this data in html
in java I use this :
public void SaveCommande(Commande c) {
try {
org.hibernate.Transaction tx = session.beginTransaction();
session.save(c);
Iterator it = c.getFichiers().iterator();
while(it.hasNext())
session.save((Fichier)it.next());
tx.commit();
} catch (Exception e) {
e.printStackTrace();
}
}
do you have any idea
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I have this error when I run my project jsf2.0
Avertissement: StandardWrapperValve[Faces Servlet]: PWC1406: Servlet.service() for servlet Faces Servlet threw exception
java.lang.NullPointerException
at com.sun.enterprise.v3.services.impl.monitor.MonitorableSelectionKeyHandler$CloseHandler.notifyClosed(MonitorableSelectionKeyHandler.java:94)
at com.sun.enterprise.v3.services.impl.monitor.MonitorableSelectionKeyHandler$CloseHandler.remotlyClosed(MonitorableSelectionKeyHandler.java:90)
at com.sun.grizzly.BaseSelectionKeyHandler.notifyRemotlyClose(BaseSelectionKeyHandler.java:233)
at com.sun.grizzly.util.OutputWriter.notifyRemotelyClosed(OutputWriter.java:353)
at com.sun.grizzly.util.OutputWriter.flushChannel(OutputWriter.java:148)
at com.sun.grizzly.util.OutputWriter.flushChannel(OutputWriter.java:76)
at com.sun.grizzly.http.SocketChannelOutputBuffer.flushChannel(SocketChannelOutputBuffer.java:326)
at com.sun.grizzly.http.SocketChannelOutputBuffer.flushBuffer(SocketChannelOutputBuffer.java:398)
at com.sun.grizzly.http.SocketChannelOutputBuffer.endRequest(SocketChannelOutputBuffer.java:389)
at com.sun.grizzly.http.ProcessorTask.action(ProcessorTask.java:1090)
at com.sun.grizzly.tcp.Response.action(Response.java:268)
at com.sun.grizzly.tcp.Response.finish(Response.java:412)
at org.apache.catalina.connector.OutputBuffer.close(OutputBuffer.java:341)
at org.apache.catalina.connector.CoyoteOutputStream.close(CoyoteOutputStream.java:187)
at java.nio.channels.Channels$WritableByteChannelImpl.implCloseChannel(Channels.java:469)
at java.nio.channels.spi.AbstractInterruptibleChannel.close(AbstractInterruptibleChannel.java:115)
at com.sun.faces.application.resource.ResourceHandlerImpl.handleResourceRequest(ResourceHandlerImpl.java:296)
at javax.faces.application.ResourceHandlerWrapper.handleResourceRequest(ResourceHandlerWrapper.java:125)
at org.primefaces.application.PrimeResourceHandler.handleResourceRequest(PrimeResourceHandler.java:85)
at javax.faces.webapp.FacesServlet.service(FacesServlet.java:591)
at org.apache.catalina.core.StandardWrapper.service(StandardWrapper.java:1539)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:343)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:217)
at org.primefaces.webapp.filter.FileUploadFilter.doFilter(FileUploadFilter.java:79)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:256)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:217)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:279)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175)
at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:655)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:595)
at com.sun.enterprise.web.WebPipeline.invoke(WebPipeline.java:98)
at com.sun.enterprise.web.PESessionLockingStandardPipeline.invoke(PESessionLockingStandardPipeline.java:91)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:162)
at org.apache.catalina.connector.CoyoteAdapter.doService(CoyoteAdapter.java:330)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:231)
at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:174)
at com.sun.grizzly.http.ProcessorTask.invokeAdapter(ProcessorTask.java:828)
at com.sun.grizzly.http.ProcessorTask.doProcess(ProcessorTask.java:725)
at com.sun.grizzly.http.ProcessorTask.process(ProcessorTask.java:1019)
at com.sun.grizzly.http.DefaultProtocolFilter.execute(DefaultProtocolFilter.java:225)
at com.sun.grizzly.DefaultProtocolChain.executeProtocolFilter(DefaultProtocolChain.java:137)
at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:104)
at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:90)
at com.sun.grizzly.http.HttpProtocolChain.execute(HttpProtocolChain.java:79)
at com.sun.grizzly.ProtocolChainContextTask.doCall(ProtocolChainContextTask.java:54)
at com.sun.grizzly.SelectionKeyContextTask.call(SelectionKeyContextTask.java:59)
at com.sun.grizzly.ContextTask.run(ContextTask.java:71)
at com.sun.grizzly.util.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:532)
at com.sun.grizzly.util.AbstractThreadPool$Worker.run(AbstractThreadPool.java:513)
at java.lang.Thread.run(Thread.java:722)
do you have an idea
thanks
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You are trying to invoke a method on an object that is referencing nothing.
Use the debug Luke.
Panic, Chaos, Destruction. My work here is done.
Drink. Get drunk. Fall over - P O'H
OK, I will win to day or my name isn't Ethel Crudacre! - DD Ethel Crudacre
I cannot live by bread alone. Bacon and ketchup are needed as well. - Trollslayer
Have a bit more patience with newbies. Of course some of them act dumb - they're often *students*, for heaven's sake - Terry Pratchett
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I have just heard about the 'Designing to Interfaces' concept.
I am required to implement this design methodology very soon, but I am not fully sure how it works.
What I learned so far is this:
Example A
-------------
Here, using a ShapeInterface decouples this Main app from any subshape object (Rectangle, Triangle, etc.).
So if I need to add a Shape type object in the future, I don't have to modify the client code because it's been 'coded to the interface'.
I only have to change the actual implementation in the concrete class itself.
ShapeInterface shape = ShapeFactory.getNewInstance("triangle");
shape.draw();
Example B
-------------
This code is easy to break because this Main app will be tightly coupled to every future shape object I need (if there comes a Rectangle, I will need to change the code to instantiate a Rectangle etc.).
Also, the implementations are different and so I have to apply the appropriate implementation (Rectangle.draw(), Triangle.draw(), etc.)
Triangle triangle = ShapeFactory.getNewInstance("triangle");
triangle.draw();
I understood this concept. Using an interface so that you won't have the change the code that uses the underlying concrete classes. Ok, understandable. I see the advantage.
Here's the concept that [b]I don't understand[/b]:
Example C
-------------
This example illustrates composition instead of inheritance (Object A has an Object B rather than IS-A B).
A can't print directly, it has to delegate to B. Fine, I understand that. What I don't understand is the advantage of this.
Couple of questions:
1) How was it decoupled?
2) Will putting the interface in between A and B decouple their relationship?
3) What if there was no interface between them? Then A would be tightly coupled to B?
4) If B disappears, can I simply replace it with a C class thanks to the interface?
If I don't understand these concepts then I can't move on in my design.
public interface ABInterface {
public void print();
}
public class A implements ABInterface {
private B b;
public A() {
b = new B();
}
public void print() {
b.print();
}
}
public class B implements ABInterface {
public void print(){
System.out.println("Testing B");
}
}
Ok, so that's that. However, I have another big problem:
Say I have a couple of classes that implement a particular interface. Now say that later, there is one method in that interface that I don't need anymore and thus need to delete.
Then it will cause a ripple-effect to the classes that implemented that interface because the implementation won't be correct anymore.
How do I avoid/deal with this?
It's quite a problem..
Any ideas on this?
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