I've created a Java project from existing source with an Ant build script in Eclipse. I cannot run my project because Eclipse tells me that there is at least one error in it.
Now, I know that the project runs fine on the command line, so I suspect an Eclipse configuration error.
As far as I can tell, the only feedback that I have from Eclipse is
a little red X on my project in the Package Explorer window
(source: gregmattes.com)
and dialog window when I try to run the project says there are errors in the project
(source: gregmattes.com)
This is all wonderful, but what is the error?
Is there a "show me the next error" button somewhere?
In the past, on other Eclipse projects, I've notice other little red X's on folders containing source files with errors, the little red X's appear on the source files as well. I scanned (manually) through all of the source files and I haven't found any other red X's (again, where is the "next error" button?).
If I select the "Proceed" button I am greeted with a java.lang.NoClassDefFoundError for my main class, which makes me suspect a classpath issue. I've checked the classpath, and I'm fairly certain that it's correct. Is there a way to see the exact jvm command line that Eclipse is invoking? I realize that it might be invoking the JVM programmatically, and not on a "real" command line. In any case, is there a way, other than the run configuration dialog, to see what is actually happening when I hit the "Proceed" button?
The errors are shown in the Problems view. If it is not opened, go to:
Window > Show View > Problems
Also accessible with the keyboard shortcut Alt+Shift+Q,X
Selecing Window -> Show View -> Problems will open the Problems view, that should have a list of all problems, their location and nature (it can be configured to show only project- or file-local problems, so you may also have to click on the project). Most likely you have a config error in your project, e.g. a reference to a JAR library that cannot be found.
View Errors/Warnings Project based
if you get that kind of an error which shows a red cross on the project folder just refresh that project right clicking on it i was having the same problem as above so try and see...
Related
Using eclipse to build a java project, I hit the Build Project button, there is no discerneable feedback/output whatsoever?
How can I tell that a build, happend and succeeded?
I have looked that in the filesystem the Project directory has indeed a /bin directories with compiled *.class files, so I now that something was build, but I look for a way to have eclipse give me that information.
How to configure eclipse to give output (i.e. to the console, status bar, if necessary message popupbox) about that some building happend.
As such you should get a popup window (shown in my last screenshot) showing the progress of your build, but in case if you are not getting then you can follow below steps to get "Progress" view of the Eclipse which shows progress of everything in the Eclipse.
And then build the project:
And you should get the progress information
As an aside: how to identify if Eclipse project has error? - If you project has build errors (it could be Java build problems, or JS or XML issues) then in the "Project Explorer" you will see a cross-mark-inside-red-square against that project, see a sample below:
Update: Another possibility to double check - make sure you are not running progress bars in the background, to verify that go to Window --> Preferences --> General and make sure "Always run in background" is NOT checked.
Further reading: this
I am new to Java programming language and the IntelliJ IDEA 2017.1 IDE.
I just installed the IDE and I activated all the various inspections but the IDE is unable to detect the errors any time I make a mistake such as omitting a bracket or a semicolon.
This image displays the activated inspections:
This is a screenshot of my code with multiple errors but no detected by the IDE:
Kindly help me solve this problem.
Java file is not analyzed since it's located outside of the source root. You need to either relocate the file or reconfigure your content roots so that it resides under the folder configured as the Sources root.
Sources root is marked in blue in the project view. Here is the example of the properly configured project (notice the class icon is different than on your screenshot):
One more reason could be IntelliJ is running on power saver mode, this could be disabled following way:
File Menu -> Power Saver Mode
This is finally what worked for me! Phew!
My Problem: Whenever I exit Intellij and try to open up an old/existing project, I have trouble getting the builds and execute to work on my localhost. I'm just using localhost.
Here are the steps that finally worked on my localhost environment:
1. Go to Project Structure and Select Project
a. Set the SDK to 10 (“Java Version 10.0.2”) or whatever you are using.
b. (I think this was the main step I was missing) Set the project compiler output to point to where I want the compiled output to sit: C:\Users\kbala\OneDrive - MatrixCare\SoftWLearnings\Javamyfun\NewHelloWorld\out
c. Project Language Level: I chose “SDK Default”
2. Go to Project Structure and Select Modules
a. Click on src (this is where my source code sits).
b. Then, Click on the “Sources” folder icon on the top. This adds src to the “Source folders” on the right. You will see the color change to Blue
c. Click ok.
3. Then, click on “Add Configuration” (top right corner of Intellij)
a. Select + at the top left hand corner.
b. Select “Application”
c. Change the name to “Main”
d. Now click on the Ellipsis (three dots) in “Main Class”. You should now see your Main Class. Select it.
e. You should now see the execute arrow at that top right of Intellij. And you should see the build icon (Hammer).
This should work!
If you use a build system (Maven, Gradle, etc.):
Open its panel in IntelliJ, then click the reimport button. For Gradle, this button looks like a sync icon and its hovertext says "Reload All Gradle Projects".
Why it works:
Since the build system is in charge of compiling your code, it knows which files are source code. It would be a waste of computing power to look for missing semicolons in a compiled binary file, so IntelliJ won't try to find errors until it knows the file is source code.
Most build systems, Maven and Gradle included, are also dependency managers. When you write code that uses libraries or depends on a different module, IntelliJ needs to be able to understand the dependency to tell you whether your code makes sense, or whether you made a mistake like forgetting an import statement or passing the wrong type of argument into a library function. When IntelliJ doesn't understand your dependencies, it displays all your uses of imported code in red text.
I was getting the same issue, I just clicked on the re-import button on the maven panel and it solved the problem .
I had the same issue and here it is how I solved it:
Some files where ignored and I Unignored them. To do this go to Maven tab on the right panel -> right click on each project that is in grey color and click Unignore projects.
I'll add an another reason for it. For me it was Reader mode enabled. I was not even been aware of its existence. Can be disabled in Settings -> Editor -> Reader mode.
In my case was a maven option!
When you open the proyect in intellij, it create a notification.
Am having problems with development in android as all my lines of code in all the files in the src folder where am placing my java files have errors on them. I do not know where the problem is coming from!
First had problems where 'R' was underlined in red. then after Ctrl+Shift+O, I exited my eclipse and on opening it, that's what I saw on my java files
Go to
Project Properties>Java Build Path>Libraries tab
and make sure JRE is added, if not, click "Add Library..." and add it.
All errors seems related to Android's specific classes:
you may have a problem with you Eclipse+ADT installation
you may have pasted the code into the wrong type of project
you may simple missing the corrisponding import
Last is simplier to verify, just hover with mouse over the error and see if Eclipse suggests you to add a specific import
I am working on a project in Eclipse. Usually, whenever there are compilation errors in a particular file, the file name in the Package Explorer view is shown with a red box and a cross. This helps to find files with compilation errors easily.However, in one particular project, I have some files with compilation problems, but those are not shown with red in the package explorer. Only when I open the files in eclipse, do I see the compilation errors. Also, this behavior is happening only in one project. Other projects are showing compilation errors properly in the package view. Any idea why this is happening ?
Is there an error red cross on the project?
Check the Problems view. (Window -> Show View -> Problems)
It could be that there is a build path error, or another error at the project level.
Often I've found that "cleaning" the project helps show those errors in the package explorer. Go to Project -> Clean... and select the projects you want to recompile.
Also it might even be easier to use the error view to jump directly to the source of your error without the lengthy way using the package explorer.
I am writing the code in eclipse. In my project explorer there is an error(red x mark) displayed on my project name. But there are no errors in the other sub folders.Can any one say where can i find those errors.? What is to be done to find the problem. Thanks in advance
The errors from Eclipse are usually avaiable from Error Log View
Window -> Show View -> Erro Log View
Also you can try to clean and rebuild the project.
One possible cause for such thing is build path issues. Go to your project build path and look at the list of included jars: check if you have any jar marked with the same red x. Also, check the eclipse "Problems" tab.
Go to the 'Problems' tab (hit Ctrl-3, then start typing Problems). It will give a description of what's wrong.