Implement HashMap Put And Get Methods Without Using Java Collection Framework?
Feb 11, 2014How to implement HashMap put and get methods without using Java Collection framework?
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Populate Data In JSP Page - Collection Framework
Feb 20, 2015I have one table in DB i.e. emp. I want to perform all CRUD (insertion,selection,deletion,updation) in DB. Now i want to populate that data in jsp page. Which Collection framework?
View Replies View RelatedWhich Collection Framework Class Will Delete Data
Jun 19, 2014I got a question , which collection framework class will delete data if we call "get".
View Replies View RelatedWhich Two Method HashMap Key Object Should Implement
Jul 25, 2014Which two method HashMap key object should implement?..
View Replies View RelatedCreate A Class Which When Implemented Requires To Have HashMap And Methods
Oct 13, 2014I want to make several classes which extend different objects and add additional functions to simplify them and make their purpose in my projects more narrow and make their instances easier to use. So an example, Image class which extends BufferedImage and the constructor in Image class directly loads the file without having to create it first and then have to use Try Catch and all that additional code. Now, here is where my question comes in. Can I make an class, an abstract class or something which can be IMPLEMENTED into these several classes such as the Image class, and in doing so those several classes will have to have (like unimplemented methods) a HashMap<String key, ChildClass instance_as_value>, child class being the Image class as an example.
So I would have something like public class Image extends BufferedImage implements Library, and this class, because it implements Library will have a HashMap<String key, Image value> in it or it's parent class.
Implement And Compare Reverse Methods From List
Oct 5, 2014What approach Collections.reverse() uses to reverse list? My task is to implement and compare reverse methods from list and i already did reveres with Recursion, Swap, Reading backward with creating reversed copy.
Does Collections.reverse() use different approach from those i already did?
Java Exception Handler Framework
Dec 30, 2014I have a Query, what is the exception handling framework used my project, but we actually did not use any framework ,we used just normal try catch and throws, so what is the exception handling framework, when I browsed through net I found something like JEHA, so is there any other framework available.
View Replies View RelatedAdditional Methods From Specific Classes That Implement Interface
Jan 8, 2014I am writing a game in Java for Android (although my question isn't Android or Game Dev specific).
I have a SceneManager class and a Scene interface and then various other classes that implement the Scene interface (Code at the end of this post).
Basically, in my MainGame class (which also implements the Scene Interface for Touch Event capturing purposes) I hold the bulk of my game code. Methods in this class are then called from my Level classes. (most of these are needed in all levels so it makes sense to hold them here and call them from the levels to eliminate unnecessary code duplication)
So, I have Level1, Level2......... Level20 classes which all implement Scene.
Now, the problem comes because in only 2 of my Levels something can happen (that can't in the other 18) and I need to run a response method in these 2 levels (the method isn't exactly the same, the response to this event happening is different for both levels).
To run common methods from my classes, I use my Scene Manager like this:
SceneManager.getInstance().getCurrentScene().updateLogic();
SceneManager.getInstance().getCurrentScene().render();
(The above is from my gameloop) - So it will run the updateLogic(); and render(); methods from whichever is the current scene (Level).
Scene is changed like so:
SceneManager.getInstance().setCurrentScene(LevelX);
This works great as all Level's have an updateLogic(); and render(); method.
So from my mainGame class, I am doing something like : (pseudo code)
public void checkIfSomethingHappened(){
if (something happens){
if (currentLevel==5){
Level5.response();}
[Code]....
The above would be called from my 2 level classes. So something like:
MainGame.checkIfSomethingHappened(); //Called in addition to the normal methods that make up that level
I don't really want to have this (second) 'if' statement here in the middle of my performance critical game loop.
What I'm after is something like this:
if (something happens){
SceneManager.getInstance().getCurrentScene().response();
}
However, this would require me to put stubs in the other 18 classes.
I'm thinking there must be a way to do this as the SceneManager already knows the current scene so it seems a waste checking it again via an if (or switch) statement. What is the best way to do this without having to put stubs into classes that don't require this method?
Java Collection Date Sorting
Apr 20, 2015I have Date as listed below:
17/03/2015 09:38:39 AM
17/03/2015 10:52:26 AM
10/03/2015 08:30:56 AM
02/03/2015 09:18:10 AM
02/03/2015 09:37:23 AM
02/03/2015 11:25:01 AM
02/03/2015 11:29:00 AM
02/03/2015 11:42:38 AM
02/03/2015 12:04:39 PM
02/03/2015 12:09:05 PM
02/03/2015 01:17:09 PM
02/03/2015 01:29:08 PM
I want them to sort them as per below result: (Same date one should be sort by timestamp)
17/03/2015 10:52:26 AM
17/03/2015 09:38:39 AM
10/03/2015 08:30:56 AM
02/03/2015 01:29:08 PM
02/03/2015 01:17:09 PM
02/03/2015 12:09:05 PM
02/03/2015 12:04:39 PM
02/03/2015 11:42:38 AM
02/03/2015 11:29:00 AM
02/03/2015 11:25:01 AM
02/03/2015 09:37:23 AM
02/03/2015 09:18:10 AM
I tried using Collection.sort using compareTo but result is not expected...
New ArrayList Java Collection Types
Jun 26, 2014I am looking at a snippet of code in my "learning Java 4th edition" by Orielly and there is a small snipped of code which says:
Java Code: Date date = new Date();
List list = new ArrayList();
list.add( date );
..
Date firstElement = (Date)list.get(0); // Is the cast correct? Maybe. mh_sh_highlight_all('java'); so I am typing the same thing in my compiler in a small Driver class and for some reason I have an error and Im dumbfounded...
Java Collection Date Sorting
Apr 20, 2015I have Date as listed below:
17/03/2015 09:38:39 AM
17/03/2015 10:52:26 AM
10/03/2015 08:30:56 AM
02/03/2015 09:18:10 AM
02/03/2015 09:37:23 AM
02/03/2015 11:25:01 AM
02/03/2015 11:29:00 AM
02/03/2015 11:42:38 AM
02/03/2015 12:04:39 PM
02/03/2015 12:09:05 PM
02/03/2015 01:17:09 PM
02/03/2015 01:29:08 PM
I want them to sort them as per below result: (Same date one should be sort by timestamp)
17/03/2015 10:52:26 AM
17/03/2015 09:38:39 AM
10/03/2015 08:30:56 AM
02/03/2015 01:29:08 PM
02/03/2015 01:17:09 PM
02/03/2015 12:09:05 PM
02/03/2015 12:04:39 PM
02/03/2015 11:42:38 AM
02/03/2015 11:29:00 AM
02/03/2015 11:25:01 AM
02/03/2015 09:37:23 AM
02/03/2015 09:18:10 AM
I tried using Collection.sort using compareTo but result is not expected.
Java Iterate Over Collection Not Working As Expected
Aug 6, 2014I am currently working on a Java project, below are my attempts at coding so far:
public class MyZoo
{
// zoo identifier
private String zooId;
// a number used in generating a unique identifier for the next animal to be added to the zoo
private int nextAnimalIdNumber;
// zstorage for the Animal objects
private TreeMap<String, Animal> animals;
[Code] ....
I currently cannot get the printAllAnimals() method to work as it should.
When executing the method printAllAnimals(), it does not do anything, when it is supposed to use the Collection object c, so that animals stored in the zoo can easily be checked.
Java EE SDK :: CDI Bean Cannot Access Public Method Of Unmodifiable Collection
Jan 10, 2010I've got a CDI bean which is a facade for a JPA entity. Such entity has got a many to one relationship with itself and I've got the following method:
public Set<Account> getChildren() {
return this.children;
}
which is called in a JSF/Facelets page:
<h:commandLink action="#{accountController.destroy}" value="#{bundle.ListAccountDestroyLink}" rendered="#{item.children.size() == 0}"/>I then decided to return an unmodifiable set and changed getChildren() accordingly:
public Set<Account> getChildren() {
return Collections.unmodifiableSet(children);
}
The page now reports this error:
java.lang.IllegalAccessException: Class javax.el.BeanELResolver can not access a member of class java.util.Collections$UnmodifiableCollection with modifiers "public"
at sun.reflect.Reflection.ensureMemberAccess(Reflection.java:65)
at java.lang.reflect.Method.invoke(Method.java:588)
[Code] ....
javax.el.BeanELResolver is incorrectly failing because it's trying to invoke the size() method using reflection without correctly taking into account the method visibility (which is indeed invokable programmatically). I'm running NetBeans 6.8, Glassfish 3.0 and jdk1.6.0_17.
Is this a bug in BeanELResolver?
Java Topological Suite (JTS) - Retrieve Intermediate Lines From Geometrical Collection
Apr 25, 2014I need to retrieve all Line Strings from a Geometrical Collection(of line strings) lying between two coordinates (Coordinates are taken from existing Line Strings in the Geometrical Collection).
I am using JTS library. I tried intersection() function but it worked only for linear geometries not for curved. How to get the output in the most efficient way.
Convert JSON String To HashMap In Java
Sep 9, 2014How can I convert JSON string to HashMap. My JSON string is like
{
"AvailableDeliveries": {
"500": {
"code": "INOFFICE",
"desc": "In Office",
"id": 500,
[code]....
I looked on other examples which have collection of object but I have this extra top level object "AvailableDeliveries" not sure how to handle that level.
How To Use Regex As A Key In Hashmap To Match Given String With Key In Java
Apr 3, 2014I have a table which contains list of regular expression and its corresponding value.I have to fetch those value and put it HASHMAP where regex as key.I have to compare the each key with the given string(input) and If matches I have to get the corresponding Value for the regex.
View Replies View RelatedEfficient XML Parsing For Count Using Java Hashmap?
Aug 20, 2014I am kind of new to Java. I have a query.. look at it. Have an xml like
<ProductList>
<Product Quality='Good' color='Blue'>
<Details ItemID='1001'/>
</Product>
...
..
</ProductList>
The <Product> tags can run into hundreds or thousands. Quality can have values like Good, Bad, Damaged. Color can also have various values (Blue, Red ..)
ItemID can repeat or can be different. So I want group by ItemID->Color->Good count or BadCount and TotalCount as below.
I want to get a sum like
<ProductList>
<ProductType ItemID="1001">
<Product_Detail CountGood="1" CountBad="2" CountTotal="3" Type="Blue"/>
</ProductType>
...
...
</ProductList>
I think using Hashmaps (Hashmap1 for ItemID, Hashmap2 for color, Hashmap3 for quality) may do the work. But I have to parse the xml number of ItemID's multiply-by number of colors multiply by various colors times for this.
Any better algorithm is there in performance perspective using Java.
Servlets :: URL Routing Without Using A Framework
Feb 18, 2015I am seen that ASP.NET apps have a handy feature called URL Routing. How will one implement this in Java without the use of heavy frameworks like Spring MVC ? How do you even begin writing a URL Router if there isn't anything available?
View Replies View RelatedServlets :: Which Framework To Choose
Aug 11, 2014I have good knowledge of servlet,jsp. I've also worked on mvc pattern and now looking to learn a web framework but i'm not sure which to choose between spring mvc OR struts.Should i first do struts and then go for spring or can i choose spring directly?
View Replies View RelatedServlets :: J2EE Without Particular Framework
Jul 24, 2014Is it possible to develop huge enterprise applications without any particular framework?
Just with JSP, Servlets and Javascript/Ajax stuffs?
Swing/AWT/SWT :: Implement CSS In Java Via A JEditorPane
Aug 5, 2014I'm trying to implement CSS in Java via a JEditorPane and an HTMLEditorKit. The CSS is included below. It *should* create a container with one on the left, small, and one on the right, large. It works flawlessly on JSFiddle [URL] ...., but on Java, it won't put the two divs next to each other. Is this a problem in Java/Netbeans or is it my problem? It creates the divs, but beneath each other. The JEditorPane is wide enough for all of them to fit.
Coding:
Java:
private void loadBulletins() {
//<editor-fold defaultstate="collapsed" desc="HTML/CSS Script">
String eBullStyles = "#divMsgs{ "
+ "height: 99px; "
+ "margin: auto; "
+ "background-color: #3399FF; "
[code]....
How To Implement Clock / Timer In Java
Jun 10, 2015How do I impliment a clock/timer in Java? The program saves files in memory for future use. I've included part of the program below I'd like to add a timer to check if the file was changed every 10 minutes. I have included part of the program below.
static FastDateFormat fastDateFormat = FastDateFormat.getInstance("MM/dd/yy HH:mm:ss");
private static final class FileContentsObject {
private long cachedTime; // currentTime
private long lastModifiedTimestamp;
private List<String> contents;
[Code] .....
Difference Between Multithreading With / Without Executor Framework
Mar 16, 2015Difference between multithreading with and without executor framework.
View Replies View RelatedConnecting Library And Swing Framework
Nov 8, 2014May I know what it means when you say "What is the OOP mechanism is used to link the library and the swing framework?"
What are the examples of OOP mechanisms? Is there a website explaining this in detail?
On Play Framework Connecting To Eclipse
Nov 6, 2014Question 1: Upon importing the Play Framework content in Eclipse there's a default codes as localhost:9000 is immediately routed to play framework website controllers, checked and running fine test, checked and running fine conf, checked and running fine the problem is the views under app on all youtube tutorials and other websites, the contents of views is editable but when my brother tried to, he cant edit it
Question 2: Is there an easy tutorial on POST, PUT, GET, and DELETE for eclipse-playframework
Question 3:my brother is using POSTMAN - RESTCLIENT to test his HTTP METHODS (post, put, get, and delete)and is there a tutorial where they also test the HTTP METHODS using POSTMAN?
Implement Multiple Inheritance In Java Using Interfaces?
Jan 12, 2014how can i implement multiple inheritance in java using interfaces. if interfaces have some methods having same name then how to distinguish that ?
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