Java
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Need help understanding the following Java syntax
public void printPixelARGB(int pixel){ public void printPixelARGB(int pixel){ int alpha = (pixel >> 24) & …… -
24 hours in simpledateformat() and milliseconds in Java
I'm building a DAQ software, and now I'm creating a log file I want to display the time on each item A simple code (un…… -
Java – how does Tomcat recognize servlets specified with annotations?
Before servlet 3.0, you need to provide URL patterns and servlet classes in web Configure servlet. XML Whenever a requ…… -
How do I format a date range in Java?
I have two appointments - start and end I want to format them so that when the month matches, they will crash to a sta…… -
Java – why does the execution order between printstacktrace () and other methods seem uncertain?
In the following code snippet, the printStackTrace () method is called in the catch block. After running the program, …… -
Java – why link string Will trim () throw an exception?
Sorry, if this is a stupid question, but I can't find an explanation I have a string like this: String str ="This is 5…… -
Java – override generic methods using non generic implementations
I was trying generics in Java and thought of this example If I have classA < T >, I can override it with Subclas…… -
Java – refresh the Android viewpager fragment on refresh
I'm new to Android. I really don't understand why the dynamically added fragment content (such as some images added af…… -
Java – calling the run method directly is not a good practice
In most cases, I want to run a piece of code in a new thread, which will take some time, but in some cases, I want to …… -
Java – develop a simple ORM
I want to develop a simple ORM that performs crud functions Shold, do I use reflection? Solution Yes, hibernate uses r…… -
Java – using import some directory.* Worse performance?
What is better performance use import some.directory.*; or import some.directory.classNeeded; Or is there no performan…… -
Java – Destroy () or finalize () is called first in the servlet?
In servlet, call destroy () before or after finalize (). Solution First call destroy() Servlet container will call des…… -
Java – what’s the difference between wrapping alfresco extensions as AMP and jar?
I want to understand the consequences of packaging alfresco extensions as jars rather than as amps I'm building alfesc…… -
Convert CIDR notation to IP range in Java
See the English answer > converting CIDR address to subnet mask and network address 11 For example, for CIDR 192.16…… -
Java – how to add icons to items in the navigation drawer
I want to place icons next to items in my navigation drawer. I have set such icons: Titles = getResources().getStringA…… -
How to interrupt a thread blocked by some socket IO operations without closing
I really want to know how to interrupt a thread blocked by some I / O operation? I / O is through socket, I don't want…… -
Java: what is the correct way to convert a string to a valid amount (BigDecimal)
I must convert the incoming string field to a BigDecimal field representing a valid amount, for example: String amount…… -
Java – how to perform ant path mapping in the ‘War’ task?
I have several jar file schema sets, such as <patternset id="common.jars"> <include name="external/castor-1.…… -
Is memory allocated for unused fields in Java?
I want to know how memory allocation works in Java I have a class duck with two instance variables int size and string…… -
Loading and saving block – based games in Java XML or txt?
I have been making a sim game based on 2D tiles for some time, and everything is going well! Thank you for this websit…… -
Java – PowerManager on Android devices WakeLock
I want to implement a wakelock in my Android application I have the following code in oncreat(): pm = (PowerManager) g…… -
JavaFX – how to add a container in the anchor pane
I have a simple project that contains fxml. XML with a splitter So fxml is like this: <AnchorPane id="AnchorPane" p…… -
Java – VTD – XML parsing performance (key factor of speed) Request feedback / comments
I'm about to use VTD XML (in http://vtd-xml.sourceforge.net/ Found), but I'm interested in getting feedback on any act…… -
How to truncate PostgreSQL tables from JDBC
I have a PostgreSQL database. I want to truncate some tables using JDBC What do I do? This is what I've tried, but the…… -
ORM – primary key – native, sequence or GUID key?
When I read this and this, and then read this (which ironically quotes the other two), I found that I wanted to know h…… -
Java – JSF – session scope beans shared by browsers on different machines
We have a search form where filters are bound to properties on managed beans (session scope) It is not a component bin…… -
Previous entry iterator – Java [copy]
See English answer > iterator has next() – is there a way to get the previous element instead of the next one? 10 I…… -
Java – how to implement some if then logic using JSF and facelets?
I have a bean with live state Depending on the status value, different CSS classes should be applied to render it So I…… -
Java parentheses flip string
How do I replace a string so that "(" becomes ")" and ")" becomes "("? Solution use. Replace (), but if you replace) (…… -
Java – how to use spring roo to create @ entity without @ version field?
I use spring roo and JPA (hibernate) as my entity model I don't want to have a @ version field in some entities How ca…… -
GUI Java program requiring action event button
I am making a simple java program representing the Microsoft Word menu bar. I add an exit button in the file menu... I…… -
Throw exceptions only in debug mode in Java
Even if there are problems, I want to avoid collapse That's why I don't want to throw exceptions that I know won't be ……