Gradle finds wrong JAVA_HOME even though it's

问题:

When trying to run gradle, I get the following error:

# gradle

ERROR: JAVA_HOME is set to an invalid directory: /usr/lib/jvm/default-java

Please set the JAVA_HOME variable in your environment to match the
location of your Java installation.

However, when I check the JAVA_HOME variable I get:

# echo $JAVA_HOME 
/usr/lib/jvm/java-7-oracle

My JAVA_HOME is defined in .bashrc and I have double checked that it is set as the source.

Running java -version also confirms that JAVA_HOME is set correctly and is on the PATH.

# java -version
java version "1.7.0_51"
Java(TM) SE Runtime Environment (build 1.7.0_51-b13)
Java HotSpot(TM) 64-Bit Server VM (build 24.51-b03, mixed mode)

I have also checked that /usr/bin/java symlinks to /etc/alternatives/java which in turn correctly symlinks to /usr/lib/jvm/java-7-oracle/jre/bin/java

Additionally I've checked that there are no duplicate JAVA_HOME definitions in .bash_profile or /etc/profile.

So my question is how/why does Gradle find /usr/lib/jvm/default-java, and more importantly how do I point it to the correct directory?

Other programs which require the JDK work fine, so I think its a Gradle issue. I've also tried reinstalling Gradle which made no difference.

I'm running 64bit Xubuntu (Ubuntu 13.10 base)

回答1:

Turns out that the particular Gradle binary I downloaded from the Ubuntu 13.10 repository itself tries to export JAVA_HOME. Thanks to Lucas for suggesting this.

/usr/bin/gradle line 70:

export JAVA_HOME=/usr/lib/jvm/default-java

Commenting this line out solves the problem, and Gradle finds the correct path to the Java binary.

If you just download the binary from their website it does not have this problem, It's an issue with the Ubuntu repo version. There also seem to be some other issues with 13.10 version.

回答2:

add a symbolic link

sudo ln -s /usr/lib/jvm/java-7-oracle /usr/lib/jvm/default-java

回答3:

For me this error was due to the reason Gradle as installed as sudo and I was trying as default user to run Gradle.

Try:

sudo gradle -version

or

sudo gradle -v

回答4:

Solution is to make JAVA_HOME == dir above bin where javac lives as in

type javac

javac is /usr/bin/javac   # now check if its just a symlink

ls -la /usr/bin/javac 

/usr/bin/javac -> /etc/alternatives/javac   # its a symlink so check again

ls -la /etc/alternatives/javac  # now check if its just a symlink

/etc/alternatives/javac -> /usr/lib/jvm/java-8-openjdk-amd64/bin/javac

OK so finally found the bin above actual javac so do this

export JAVA_HOME=/usr/lib/jvm/java-8-openjdk-amd64
export PATH=$JAVA_HOME/bin:$PATH

above can be simplified and generalized to

which javac >/dev/null 2>&1 || die "ERROR: no 'javac' command could be found in your PATH"
export JAVA_HOME=$(dirname $(dirname $(readlink -f $(which javac)  )))

回答5:

Try installing latest version of gradle,

sudo add-apt-repository ppa:cwchien/gradle

sudo apt-get update

sudo apt-get install gradle

If we install from ubuntu repo, it will install the old version , (for me it was gradle 1.4). In older version, it sets java home from gradle as export JAVA_HOME=/usr/lib/jvm/default-java. Latest version don't have this issue.

回答6:

Did you export your JAVA_HOME? Without export, the setting will not be propagated to the commands started inside of that shell. Also, java -version does not use JAVA_HOME, rather it uses the first java found in your path. Make sure your .bashrc looks something like this:

JAVA_HOME=/path/to/java/home
export JAVA_HOME

回答7:

I faced this issue when I run the following command on Ubuntu:

ionic build android

To solve this issue, I did the following steps:

ln -sf /usr/lib/jvm/java-7-openjdk-amd64/jre/bin/java /usr/lib/jvm/default-java

Add JAVA_HOME to /etc/environment:

vi /etc/environment

Add:

JAVA_HOME="/usr/lib/jvm/default-java"

After saving, read it:

source /etc/environment

Finally, you can run build command.

回答8:

I had the same problem, but I didnt find export command in line 70 in gradle file for the latest version 2.13, but I understand a silly mistake there, that is following,

If you don't find line 70 with export command in gradle file in your gradle folder/bin/ , then check your ~/.bashrc, if you find export JAVA_HOME==/usr/lib/jvm/java-7-openjdk-amd64/bin/java, then remove /bin/java from this line, like JAVA_HOME==/usr/lib/jvm/java-7-openjdk-amd64, and it in path>>> instead of this export PATH=$PATH:$HOME/bin:JAVA_HOME/, it will be export PATH=$PATH:$HOME/bin:JAVA_HOME/bin/java. Then run source ~/.bashrc.

The reason is, if you check your gradle file, you will find in line 70 (if there's no export command) or in line 75,

JAVACMD="$JAVA_HOME/bin/java"
    fi
    if [ ! -x "$JAVACMD" ] ; then
        die "ERROR: JAVA_HOME is set to an invalid directory: $JAVA_HOME

That means /bin/java is already there, so it needs to be substracted from JAVA_HOME path.

That happened in my case.

回答9:

For me an explicit set on the arguments section of the external tools configuration in Eclipse was the problem.

回答10:

You can also go to the bin folder inside your gradle installation folder and correct the JAVA_HOME parameter in gradle.bat file. In my case, my JAVA_HOME was set to c:\Program files\java\bin The JAVA_HOME in gradle.bat was set to %JAVA_HOME%\bin\java.exe.

I corrected the JAVA_HOME in gradle.bat and it worked.

Thank you!!!

回答11:

sudo ln -s /usr/lib/jvm/java-7-oracle/jre /usr/lib/jvm/default-java

Create a symbolic link to the default-java directory.

You can find your java directory by

readlink -f $(which java) 
# outputs: /usr/lib/jvm/java-7-oracle/jre/bin/java
# Remove the last `/bin/java` and use it in above symbolic link command.

回答12:

I had a problem with this too. It said wrong directory when it was correct. So I just created a local variable with the name of JAVA_HOME omitting the final /bin/java. It worked fine for me.

回答13:

In my dockercontainer (being minimal the problem of not finding java) was, that "which" was not installed. Comipling a project using gradlew used which in ./gradlew to find java Installing which solved the problem.

回答14:

If your GRADLE_HOME and JAVA_HOME environment are set properly then check your JDK directory and make sure you have java.exe file under below path.

C:\Program Files (x86)\Java\jdk1.8.0_181\bin

As error mentioned in gradle.bat file

:findJavaFromJavaHome
set JAVA_HOME=%JAVA_HOME:"=%
set JAVA_EXE=%JAVA_HOME%/bin/java.exe

if exist "%JAVA_EXE%" goto init

echo.
echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME%
echo.
echo Please set the JAVA_HOME variable in your environment to match the
echo location of your Java installation.

It is not able to locate your java installation. So find and set

java.exe

under %JAVA_HOME%/bin if everything is correct.

This works for me (my account got disabled by client and their admin has removed java.exe from my directory.)