包含标签：Java 的文章
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Java – about sorting algorithms applied to stacks and queues
I wonder why we always use sorting algorithms (such as insert sorting or merge sorting,...) only for lists and arrays?…… -
Why does Java require char variables to use single quotes?
Why does Java require char variables to contain anything in single quotes instead of double? An example: char s = 's';…… -
Java – when using thymeleaf, the spring security sessionscope appears to be null
When the login fails with spring security, it will throw an exception and display it in my JSP, as shown below: <c:…… -
Thread contention in Java
I want to know the following procedure If I call new readerthread() Start() it works normally, but if I call new reade…… -
Java inheritance problem
Suppose I extend a class and override the methods in that class What is wrong with calling rewriting from my new class…… -
Java – use system out. Println() creates a border
Anyway, has this arrangement been created, and no string variable SH3 affects the boundary? I'm really sorry that my k…… -
Remove the JFrame from the taskbar in Java
I made a quick theme look, but I didn't find anything similar My query is: how do I prevent child windows from appeari…… -
Java – why not always increase the operator’s work on chars?
Why char c = 5; int i = c++; However, this causes a compiler error (invalid arguments / –) for the operator: int i = a…… -
Java – why does eclipse display errors in the play framework rendering method?
I received an error: public static Result home(String name) { return ok(home.render(name)); } Eclipse s…… -
Java – how to get parameters from the URL in Liferay portlet?
I used something like feed in Liferay 6 JSP of out of the box portlet such as jspf: String articleId =null; HttpServle…… -
Failed: metadata error: Java Lang.runtimeexception: unable to instantiate org apache. hadoop. hive. metastore. HiveMetaStoreClient
I closed my HDFS client while HDFS and hive instances were running Now, when I re-enter hive, I cannot perform any DDL…… -
Java – find the size of the file in the gzip file
Is there any way to find out the size of the original file in the gzip file in Java? As in, I have a 15 MB file a.txt,…… -
Storing DPI and paper size information in JPEG using java
I have the following code: ImageIO.write(originalImage,OUTPUT_TYPE,resultOutput); This is for the following javax imag…… -
For multiple lock attempts, use Java concurrent. ReentrantLock
I noticed the following code block: final Lock s = new reentrantlock(); for(int i = 0 ; i < 1000 ; i++) { …… -
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Java – how to convert dates to UTC
I need to change the date format to UTC format … I need to convert the LastModified date of the file in UTC format Sol…… -
Java – style EditText for Android
I ran Android 2.3 on my phone and noticed many applications that use ICs to edit text fields, such as square up and Tu…… -
Java – use thread. Java in my main code currentThread. Is sleep () dangerous?
In my code I'm using Thread.currentThread().sleep(sleepTime); In the main (non thread object) part of the code It seem…… -
Using threads in swing GUI in Java
I use the following code to replace a jlabel every 0.5 seconds, using the same sentence, but using another point Runna…… -
Java – how to detect the last character
I have a string. I want to know what the last character in my string is# String test="test my String #"; Solution Only…… -
Java what does it mean to call repaint () instead of calling paint (?) directly in Applet?
We override this paint method public void paint(Graphics g) { g.drawString(msg,xpos,ypos); } If we have another met…… -
Java – how to schedule a task every “n” seconds in the spring framework
How to connect to my web XML task occurs every N seconds In addition, I need to refresh the server method every 5 seco…… -
Java – why does this nested ArrayList code throw an exception?
ArrayList<ArrayList<Integer>> a = new ArrayList<ArrayList<Integer>>(5); ArrayList<ArrayList…… -
Java – why does concurrentmodificationexception appear when deleting from HashMap?
I want to delete a project from HashMap by applying criteria Consider the following codes: Set<Foo> set = myMap.…… -
Java Naming Convention
I've been studying Java hard for the past week, and so far I've been able to generate reasonable code However, I seem …… -
Dynamic array in Java
What I want to do is ... int sum[]; ... for(int z.....){ ... sum[z] = some_random_value; ... } But it gives a…… -
Loop problem in Java
What is the error in the following code? while ((char t==(char) system.in.read())!='0') Solution You cannot declare a …… -
Java – how to generate a unique ID on a web server cluster
In the following scenarios: 1 database 4 web servers How does the web server generate unique IDs for databases to make…… -
Why doesn’t Java use the out parameter in c#’s language syntax?
Although I'm not a big fan of using the out parameter in c#, I wonder why Java chose not to include it in its language…… -
How many threads run in Java?
I have this wonderful idea to speed up the time required to generate 36 files: use 36 threads! Unfortunately, if I sta…… -
Java – is it acceptable to always use ‘this’ as a monitor lock?
For example, I have a class with 2 counters (in a multithreaded environment): public class MyClass { private int cou…… -
Call the child method when converting to the parent type in Java
I am trying to complete some course work. Any help will be appreciated! I have three types of accounts that extend the……