Questions tagged as 'java'

Tagged questions
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Can you specify the database in a query in Java?

I need to connect to a different database at runtime and I do not have the slightest idea how to do it in JPA. I have a database that tells me which one I should connect to according to some parameters to follow. I make my query in the first dat...
asked by 30.05.2017 / 15:43
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Pdf not valid in Acrobat Reader with itext

I am implementing the digital signature with itextpdf. I have already signed the document with a .p12 certificate but, when I open the PDF and validate with Adode Reader, I get the message that the certificate is invalid. I have verified the sam...
asked by 30.05.2017 / 16:26
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Problem with serialization in java

I have a program, in which each user has some fixed data: ID, name, password .. and only has one that varies during the execution of the program: the balance. I have managed to serialize the fixed data, when I start the program I load them fr...
asked by 29.05.2017 / 17:02
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reading by keyboard of a registration of eight characters, the first being obligatory a letter

public ExMatricula() { } ExMatricula(String s){ super(s); } ExMatricula(int mal_formada){ this();mal_formada=mal_formada; } public int DimeProblema(){ return mal_formada; } private...
asked by 29.05.2017 / 16:58
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anonymous class implements interface; can not have arguments

I'm trying spark on maven but I get this problem I want to show me the port but the runable shows me this error    "anonymous class implements interface; can not have arguments" Code public class HelloWorldSparkStyle { publ...
asked by 04.06.2017 / 15:05
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problem with SELECT in java

I have a small code in java that before entering information in the database, search through a code if the record is already included in the database or not. If it is, it updates it and inserts it. boolean isInsert; boolean precio_...
asked by 04.06.2017 / 11:02
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Add serialized data to a JTable JTable

I have this fragment of code where the if question if it was not written in all the JTextField and if it does it creates the file (the file saves an arraylist) .. now, my doubt comes from how I do to show the data of the file in a JTable that is...
asked by 03.06.2017 / 15:39
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How to use a domain instead of an IP in Java

I have an application that works very well in Local(área local) but when I use it outside of my Local Network, I can not because I need to use a domain. So I wanted to edit it and make it functional so that it works from outside LAN...
asked by 25.05.2017 / 20:54
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Android Parcelable object when returning loses its value

hoping they are well, I have a concern. I have two activities 1) List of courses and their children are the activities - 2) Data and evaluation of the course activity The process is as follows. I select a course activity from a Expanda...
asked by 25.05.2017 / 20:12
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Problem when filling JTable with Query?

Hello Colleagues, I am programming in java in MVC pattern and I run into this loop inside my code. I'm using arraylist //Arraylist para llenar una jtable con arreglos public ArrayList<String[]> Select(){ try{...
asked by 24.05.2017 / 14:20