I teach very early coders using Eclipse, so it's imperative that I minimize distractions for them. I have all my preferences correct in Eclipse except for one: when I select "New Class", the name of the current Java Project autofills into the package field. See the image below. This is a problem because if they don't delete that content (every time!) it automatically creates a line
package my_package_name;
at the beginning of their new classes. While I know this isn't a huge deal, I worry that it's just one more thing for them to worry about ("Is that why my code is wrong?"). Is there any way to change the default content of the "Package" field in the New Class window to be blank (so it wouldn't create the package line in their source code files)?
Related
Using Alt+Enter, I can ask Intellij Idea to apply the intention action for the code under the caret. For example, if the cursor is on a class name and I have not yet imported the class, it will allow me to import the class.
Is there a way to do the same if I am somewhere else on the line (like using Control+1 in eclipse) ? Or maybe there is a shortcut to go to the next problem ?
I have written a project that includes a Character class. In this project, in a different package, I have another class that's trying to use it:
for (int i = 0; i < NUM_CHARACTERS; i++) {
Character c = new Character(10);
}
The problem is that Eclipse is automatically trying to use java.lang.Character:
What I would like to do, is find a way either via the contextual menu, keyboard shortcut, Quick Fix menu, etc. to have Eclipse provide me with alternate imports.
The issue is obviously that the class is part of the standard API, otherwise it would certainly ask me which Character class to import. Normally if you've imported the wrong one accidentally, you can just delete it from your import block at the top, and use Quick Fix to pick the right one.
But how, in this case, can I easily tell Eclipse I want to use a different class, without having to manually type the import into the top? I have a number of classes that will be named similarly to the java.lang classes, so I'm looking for a time-saving solution.
Ctrl+Space will give you an option to select the required package.
Just place the cursor at end like Character^ and press Ctrl+Space
where ^ show your cursor position. For example
Date class is present in java.util as well as java.sql, so when you will type
Date^ Ctrl + Space, it will pop-up with all the packages where Date class is present and you can choose your desired import from there.
Another way, Just delete all the auto imports & press Ctrl + Shift + O to organize imports. Eclipse will prompt you for all the place wherever there is any ambiguity in identifying the right package.
I have an existing project for which i have decided to create a GUI for in Netbeans. The problem I am encountering is the fact that every component that i drag-and-drop is private in the source and is unmodifiable. Must i create getters for everything?
I mainly just need this problem resolved for appending to the TextArea.
Thank you in advance
If you want to change that globally, go to the options dialog, then select miscellaneous, and pick the gui builder tab. You can configure the default modifier there.
By right clicking on a component in the Inspector panel, you can influence the generated code, even though it is in an editor-fold and not directly editable. For example, right click on a JList and edit the Properties > model to add text entries; right click on Code > Post Creation Code to add a code snippet affecting the selection model:
itemList.setSelectionMode(ListSelectionModel.MULTIPLE_INTERVAL_SELECTION);
Examine the code in the editor-fold to see the generated changes.
See also Introduction to GUI Building.
You should see some tags in the code, something to do with begin and end of variable area. Usually there are 2 different sets of tags, any code between those tags will regenerate when you modify the gui with the form builder.
You can write your own code outside of those tags and it should remain even after you make changes. Getters and setters are a good idea if you need to update your object from another class. I've done that before with some text areas where I had a utility class update the text in it.
Create a project in NetBeans and create a new JFrame.
Use the GUI Builder to drag some components like a button or label onto the frame and look and the source. You'll see by default that the member variables are private in the frame class.
Now go to Tools -> Options -> Misc -> GUI Builder and change something like the variables modifier to protected instead of private.
Now how do you apply those changes to the already generated code? I've tried several things like format code, fix code, etc. I've even tried cutting all the components off of the frame and then repasting them hoping to fix the issue, but it still uses the old settings.
When I create a new JFrame in the project and perform step 2 again, the changes have taken effect. Any new code generated on a new frame or file works as expected, but not the original.
This is very strange behavior, and I have to imagine there's an easy straight forward way to regenerate this code. Am I missing something?
I'm using NetBeans 7.1 and Java 7u2. Thanks in advance!
As you have already alluded to, the GUI Builder options are defaults only, for the creation of the form.
You can change most things about already-generated GUI elements.
To change the GUI components 'access' from private to protected, right-click the component in the GUI designer and select "Customize Code". At the bottom of the "Code Customizer" dialog you can change just about any aspect of the declaration of the GUI element. That dialog also lets you customise things like the constructor used for the element.
I would recommend you leave the access default at private, and only change the elements that you really need to be protected or even public.
And don't listen to the doom-sayers. We have over 600 GUI-designed forms in our application, we use the GUI designer every day, with multiple developers, and we very rarely have any issues at all.
By the way, we are using version 6.9.1 of NetBeans with Java6, so YMMV.
I had created a GUI in Netbeans through Netbeans Swing GUI creator. So I just dragged and dropped the Swing Components from the "palette" window and all the code was generated by netbeans.
Now the code is too long to maintain (approx. 10,000 lines). So some experts on SO suggested me to refactor my code.
I can refactor the code that was generated by me but I don't know how to refactor the code generated by the Netbeans as It doesn't allow editing in its generated code.
Any suggestions?
10.000 lines of code sounds like you have everything in that single class.
Start by splitting your source into Model, View and Control (MVC).
You might also be able to extract some JPanels into separate classes. One way to do this is to create a new JPanel (new file), and cut/paste your compoments from one main panel into that new JPanel. Save and compile your new panel.
Then go back to your main frame, select Beans -> Choose Bean from your Palette and choose the newly created class (com.example.YourPanel for example).
Make sure to have a backup of your application before you try this.
Well - if the code is generated, I don't see any advantages in refactoring it as long as the tool which generated it can handle it. The tool (meaning the designer in this case) will "destroy" all your refactoring work as soon as it updates the code.
However, you should split your Control/Window/... into multiple controls - then the code will automatically get shorter and you will be able to maintain your UI more easily.
As a conclusion: Do not refactor the generated code but do refactor your control.
Handcode the GUI code with layoutmanagers.
Using GUI builder tools, makes it nearly impossible to refactor GUI code. I have to use these idiotic Intellij Swing GUI designer forms. I now cannot even rename my packages in Eclipse because it wont be updated in the forms.XML file.
Stay away from GUI builders. If you want to build really complex, maintainable GUIs then do it by hand by using GridBagLayout and all the rest.
If you have to use netbeans, because of project limitations (e.g the rest of the team is, or requirements say to) then use Matisse to break up the huge form into smaller panels, each of which the designer can edit. You can do that by creating a new form, and cutting and pasting panels from the big form into the new form.
But at the same time, make sure all the business logic is moved out of the UI classes.
If you do not have to use matisse / netbeans, you can open the project in Eclipse, and edit the forms using WindowBuilder, it will do it in real java code instead of the uneditable form, so you can then chop and edit it to your heart's content.
You can extract the application logic into a separate subclass. Then, directly use the subclass. I succeeded with the following method.
Members defined by us that are relevant to the application logic moved to the newly created subclass.
Components access modifier made "protected" (they are "private" by
default). To do so: Right click -> Properties -> Code (tab) -> Set
"Variable modifier" to "protected"
Event handling methods moved to the subclass - When you are adding events to a component using properties pane it changes initComponents() function by adding the relevant code like in the following code sample. Here definition of btnNum6ActionPerformed() is added to the class with an empty body. Unfortunately btnNum6ActionPerformed() is private and no way to change the access modifier using NetBeans IDE. Hence, they cannot be overridden. To get rid of this, you can define another intermediary function and call it inside btnNum6ActionPerformed(). It is better to make the base class and its intermediary event handling functions abstract.
btnNum6.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
btnNum6ActionPerformed(evt);//Definition of this method is added too
}
});