Questions tagged as 'java'

Tagged questions
2
answers

java.lang.NumberFormatException: Invalid double: ""

I am new to this android studio and I try to make a temperature converter the problem is that no matter how hard I try to get this error it is assumed that the whole program should do object oriented    01-29 07: 44: 26.967 12711-12711 / com....
asked by 29.01.2018 / 14:54
1
answer

JPA - Problems with persist of @ManyToOne

I am working on an application that requires data from faculties and careers to be saved and I have created the following entities:    Faculty @Entity @Table(name = "uc_facultades", schema = "uc") @SequenceGenerator(name = "Facultades_id_s...
asked by 28.01.2018 / 00:06
1
answer

Identification Submenu (Group and child) selected in a Navigation Drawer on Android

Recently I have been working with Android therefore I am still a newbie as far as this is concerned. I wanted to make a small application with a Navegation Drawer taking as an example the following project: link It works very well and...
asked by 09.01.2018 / 22:40
3
answers

I can not update a field in my MySql database from Java

Hi, I'm having a problem when updating a field in my database, it does not throw me any errors, it just does not update the field in the database. I have the Product Class and a constructor that is as follows: public Producto(String strNomb...
asked by 29.12.2017 / 16:41
1
answer

Autoincrement error in jpa

This message I get when you perform the insert in the database and it does not give any errors, it only gives this message of warning .    Warning: The class RepeatableWriteUnitOfWork is already flushing. The query will be executed without...
asked by 11.12.2017 / 22:45
2
answers

Problem with combobox and duplicate items

I have a combobox that I fill it with data from mysql , the problem that I currently have is that the combobox doubles the values, for example, if I add 5 items, it will show me 5 and 5 others that are copies of the first, I leave...
asked by 27.11.2017 / 06:22
2
answers

Avoid blank lines when reading a .csv with opencsv in Java Android

I use the opencsv library to read the contents of a .csv file I have the following: String fileName = "file:///storage/sdcard1/maptest/cvs_test1.cvs"; final File file = new File(Uri.parse(fileName).getPath()); try { CSVReader reader =...
asked by 18.11.2017 / 17:50
2
answers

how to put in an array the result of the use of information of two arrays?

Hi I'm learning java, I'm doing a program where I talk about the birthdays of 5 people on days of the year (I only take the 365 days I do not take into account leap years) but I'm stuck I have the days and months in two arrays after I use those...
asked by 09.01.2018 / 18:59
1
answer

Split into special characters like '\' in java [duplicate]

Hello, I would like to know how I make a split to special characters. What I'm trying to do is take away the \ these numbers. String octa = "454246"; String[] prueba = octa.split("\"); for (int i = 0; i < prueba.length; i++) {...
asked by 08.01.2018 / 22:25
1
answer

Spring security- Sessions?

I have a project created with Spring Security and Spring MVC, and I have a url in the following way: universidad/acceso/infoNotas?idEstudiante=20 It turns out that when defining access to the URL, it is defined for the role of teacher in th...
asked by 12.02.2018 / 03:13