Develop Reference

IntelliJ Cannot start under Java 1.8.0: Java 11 or later is required

I had some problems with JRE versions, so I tried to change it using the plugin Choose Runtime. I changed it to Java 1.8.0_112-release-287-b2. Now, when trying to start IntelliJ, i get an unsupported Java version error: Cannot start under Java 1.8.0_112-release-287-b2: Java 11 or later is required. I have tried to modify the runtime path in the ide64.exe.jdk file, but it seems like the old jdk IntelliJ ran on has been deleted. I also tried reinstalling intellij, no luck either. Anyone know how to get back the JDK? do I just download it from oracle and install it in the IdeaIC2020.3\jdks\ folder?
Thanks,
Jakob

I went to the jdks folder and deleted all contents. This fixed the issue. IntelliJ started without a problem.

Java 9 and JavaFX on Fedora 27 "runtime components are missing"

I work on java project in eclipse using javafx and java-9 but i got an error:
Error: JavaFX runtime components are missing, and are required to run this application
I have installed:
java-9-openjdk.x86_64
java-9-openjdk-devel-9.0.4.11-4.fc27.x86_64
openjfx-8.0.152-12.b04.fc27.x86_64
openjfx-devel-8.0.152-12.b04.fc27.x86_64
I tried removing and installing these libs again using yum and also from .rpm packages but it didn't solve that problem.
In eclipse I specified build path in project like on screen here:
Eclipse Build Path
I tried to fix it by adding external jars: ant-java.jar, javafx-mx.jar, packager.jar but this didn't solve the issue.
My version of eclipse is Eclipse Oxygen.2 Release (4.7.2) and i got e(fx)clipse 3.0.0 . My kernel is: Linux 4.15.9-300.fc27.x86_64 I have no problem on Win 10 but i really want to work on my Fedora. I spent huge amount of time but I didn't find the solution.

I am not a Linux user but I wonder how java-9... and openjfx-8... are supposed to go together. They are just incompatible versions. You will have to find a Java distro which already contains JavaFX like the Oracle JDKs.
Update:
You find the latest version including JavaFX here:
http://www.oracle.com/technetwork/java/javase/downloads/jdk10-downloads-4416644.html

JavaFX on Android - Gradle can't find JDK

I'm trying to get JavaFX applications to run on Android by using the Dalvik JavaFX-Android SDK (provided by the JavaFX Android porting team). So I downloaded the samples provided by the JavaFX Android porting team and have been trying to run one of them on Android without much success.
Using Eclipse with the Gradle plugin I imported the "HelloWorldFxml" sample project. Then I ran the Gradle task "./gradlew androidInstall" on the project like the README file told me. But unfortunately the task cannot execute because Gradle cannot locate my JDK:
(source: forumbilder.se)
Even though my JAVA_HOME system variable is correctly set and I havn't had a problem with it before:
(source: forumbilder.se)
Anyone that can provide some insight as to how I can fix this?
Versions: Eclipse Luna Service Release 1a (4.4.1), Gradle 2.2, dalvik-sdk-8u40-ea3, Android SDK Build-tools 21.1.2, Android SDK Tools 24.0.2
Edit: The console output when running "gradlew androidinstall" on a sample project:

Even though the error message doesn't specify it, maybe it's looking for javac in your PATH? In case it's not in there try adding ;%JAVA_HOME%\bin to the end of your PATH variable (and restart Eclipse afterwards, I've had the problem of running processes not getting changes to environment variables before).

Check the Java setting in Eclipse:
Window -> Preferences
Java -> Installed JREs
Make sure that your JDK 1.8 is listed there. If it's not, add it using the Add... button.
Once the JDK is known to Eclipse, make sure that your project's settings use that JDK as a compiler, and the Gradle plugin should be able to pick up the setting from there.
In a pinch, you should also be able to run Gradle from the command line, and it should work fine since you already set the %JAVA_HOME% variable.

Basic Note
Since the release of dalvik-sdk-8u40-ea3, and in very short time, the JavaFXPorts team has released a few new versions, all of them simplifying all the process of porting a JavaFX application to Android or iOS.
They released dalvik-sdk-8u40-ea4 and they announced the release of a new plugin, that will simplify to the minimum the steps to create a mobile application from JavaFX.
While this answer may not help the OP in his particular problem, definitely it will help him and others, since everything is really simplified.
New approach
With this plugin, there's a new way of creating the HelloWorldFxml application for Android.
The new javafxmobile-plugin allows you to generate the apk with a single 'build.gradle' file.
You can find this an other basic samples here, and download the repository here.
You won't need to edit a single line, just type this on the command line, on the root of the sample, with your device connected:
gradlew androidInstall
As for previous releases, you will need JDK8u40 and Android SDK installed. No need for dalvik-sdk though, it's retrieved by the plugin.
Notice that you can open these samples from your IDE, so you will be able to modify them, and run them locally or build again the apk for your device.

Had this problem, too.
My proberties:
-Windows 7
-Dalvik SDK (dalvik-sdk-8u60-b5)
-JDK 8 (newest Version 8_60 / IMPORTANT: JDK not JRE)
-And I tried also the HelloAndroid project provided by the Dalvik-SDK-download.
So i execute the command line: gradlew installDebug
My probelm was nearly the same.
"Fail to find JDK. Please make sure there is a JAVA_HOME or JAVA8_HOME systemvariable."
#1
Created these proberties. Just like described in this post:
How to set java_home on Windows 7?
So to make everything sure, I created both with the same path. Cause I don't know exactly which one is used by gradle.
#2
This is really the hack that helps me out. Found this also in StackOverflow.
Write in your build.gradle under the android{..} stuff this line:
retrolambda {
jdk 'C:/Program Files/Java/jdk1.8.0_60' //<--your JDK-path
}
it looks like that
Then execute the same command line again and it worked for me.
I think only the 2. steps was the solution, cause I guess gradle don't look for the variable if there is a direct path to the jdk.

Android Studio Gradle project sync failed

I'm getting error:
"Gradle project sync failed. Basic functionality (e.g. eiditing) will not work properly."
And Error Log:
Error:Unable to start the daemon process.
This problem might be caused by incorrect configuration of the daemon.
For example, an unrecognized jvm option is used.
Please refer to the user guide chapter on the daemon at http://gradle.org/docs/1.10/userguide/gradle_daemon.html
Please read below process output to find out more:
-----------------------
Error occurred during initialization of VM Could not reserve enough space for object heap Error: Could not create the Java Virtual Machine.
Error: A fatal exception has occurred. Program will exit.
I was trying to delete .gradle folder as I read here. This worked yesterday but today when I started Android Studio the error showed again and deleting .gradle folder doesn't help.
I realy don't know what to do.
Does anyone have any suggestions?

Just a blind guess: try to add something like this to your gradle.properties file in the project:
org.gradle.jvmargs=-Xmx512m -XX:MaxPermSize=512m

Same issue solve in Android studio by
File -> Settings -> Compiler (Gradle-based Android Projects)
Change the "**VM options**" to
-Xmx512m -XX:MaxPermSize=512m
It worked for me .

The only way I've been able to fix this when it happens is by doing
./gradlew clean
and
./gradlew --refresh-dependencies
and then restarting Android Studio.
If that doesn't work I usually resort to reimporting the project.

I had the Same Issue, and Searched for almost 4 Days but can't able to solve the problem.
But at Last I can able to solve the problem, and for that please follow the steps.
Step 1: Check Your Java Version.
Step 2: If It is 1.7 then Download the New Version i.e JDK 1.8
Step 3: Install JDK 1.8
Step 4: Change the Java Version of Android Studio to 1.8 and the
problem solved...
It Worked for me.

changing compile setting to this worked for me

I was getting the same error in version 2.2.3,So I downloaded the latest Android Studio version 2.3.3, even in the latest version, I was getting the same error, below is my solution :-
Download the latest version of Android Studio from the official site.
In File>Project Structure>SDK Location, JDK Location should refer a 64-bit JDK ex. C:\Program Files\Java\jdk1.8.0_131, even after this, error was not fixed completely.
I checked the project structure, In the File>Project Structure>Project , the Android Plugin version was still 2.2.3, I changed it to 2.3.3 and the build is successful and everything is working smoothly.

This one worked for me.
Close the Android Studio
Delete .gradle folder from c:\users\{username}\.gradle
Open the Android Studio
Clean Project
Rebuild Project
Sync Project with gradle files. See screen shot
Cheers!

Check if the gradle path in File -> Settings -> Build, Execution -> Gradle is correct. I had incorrect path to local gradle distribution there.

None of these worked for me, so this is how I eventually solved my problem:
In the top-level build build.gradle file, remove
'classpath 'com.android.tools.build:gradle:some version number'
sync your project and make sure your gradle location is pointing at the correct directory

Updating Java and the problem is solved!
Control panel > Java > Update Now

I was in that situation, finding near no solution; finally I realized that my firewall was blocking java executable from opening ports/connecting. Try adding a firewall exception for the Java executable. This solved the problem for me.

Install trouble for Android SDK in Eclipse Helios

EDIT: I fixed it by not installing the NDK Development stuff. I don't know what it is, or what it does, but it fixed my problem.
I'm on Windows 64-bit, using Eclipse Helios, and trying to install the latest Android SDK. So far, I've been able to download and install the SDK Manager and successfully ran through its stuff.
The trouble comes in when I try to install inside of Eclipse (Help -> Install New Software). Every time I try to install using either the URL address (http://developer.android.com/sdk/installing/installing-adt.html) or the .zip file I get this error:
An error occurred while collecting items to be installed
session context was:(profile=SDKProfile, > phase=org.eclipse.equinox.internal.p2.engine.phases.Collect, operand=, action=).
Comparison method violates its general contract!
Comparison method violates its general contract!
The internet doesn't seem to have any answers that I can find. Thanks!

Late to the conversation...
But I have found this error when trying to install packages, not at all associated with Android, from older Eclipse versions, which by now includes Helios. It actually took me a while to figure out all those Eclipse project names are actually versions. At the time of this writing, Eclipse Kepler is the latest, once I upgraded (pretty much a fresh install) to Kepler and tried again to install the packages, everything worked fine.
Hopes this is helpful to somebody.

Run eclipse as administrator and install Android SDK.
You must use https://dl-ssl.google.com/android/eclipse/ for SDK installation.
See Install ADT Plugin
By the way, which version of java are you using? I reckon the error is possibly an eclipse bug, related to Java 1.7.
Try JRE 1.6 and see if it works!

You need the following tool for starting the android devolopment
(1) Eclipse ide
(2) ADT for eclipse (android plugin for eclipse)
(3) Android SDK
You get a brief idea about each of these steps from the following link
http://codeglympse.blogspot.in/2012/10/installing-eclipse-and-android-sdk.html