Netbeans 无法找到 java

Question

I am setting up a new machine after a long time.

I installed java using home brew:

brew install openjdk

In my .zshrc file I added:

export PATH="/usr/local/opt/openjdk/bin:$PATH"

Running 'java -version' gives the following output:

openjdk version "18.0.1.1" 2022-04-22 OpenJDK Runtime Environment Homebrew (build 18.0.1.1+0) OpenJDK 64-Bit Server VM Homebrew (build 18.0.1.1+0, mixed mode, sharing)

When I try to run the netbeans 13 installer pkg, I get the following message:

No Java Found NetBeans IDE cannot be installed. This software can be installed with Java 8 or newer. Please download and install the latest update of Java 8 from http://www.oracle.com/technetwork/java/javase/downloads/index.html and restart NetBeans installation.

I figured maybe I need to set the java home variable. But not sure where the correct location is. I tried:

export JAVA_HOME=/usr/local/Cellar/openjdk/18.0.1.1/libexec/openjdk.jdk/Contents/Home

But the error is still there.

1. Have I set my JAVA_HOME variable correctly ? How can I make sure that I have set the correct location ?

2. How can I get the Netbeans installer to install ? Why does it not see the JDK ?

EDIT:

If I run the following command:

/usr/libexec/java_home

Then I get the output:

The operation couldn't be completed. Unable to locate a Java Runtime. Please visit http://www.java.com for information on installing Java.

Answer 1

This is because I installed java via homebrew and did not see this message output in the end:

For the system Java wrappers to find this JDK, symlink it with sudo ln -sfn /usr/local/opt/openjdk/libexec/openjdk.jdk /Library/Java/JavaVirtualMachines/openjdk.jdk

Run the command above to create the symlink, then netbeans installation proceeds. Wasn't necessary to set path or home. Set cpp flags because cpp is cool.

Even for other versions such as 11 it may be necessary to run a similar command. Homebrew mentions it, but unless you're paying attention may not notice it at the end of the installation.

Answer 2

I suspect the problem is that the NetBeans 13 installer does not support the use of JDK 18, because NetBeans 13 itself does not officially support JDK 18. From the Release Notes (with my emphasis added):

The Apache NetBeans 13 binary releases require JDK 11+, and officially support running on JDK 11 and JDK 17 .

Also, note that:

• NetBeans 13 was released on March 4, 2022.
• JDK 18 was released 18 days later, on March 22, 2022.

So while NetBeans 13 may appear to run fine with JDK 18, it seems probable that the installer does not support the use of JDK 18, which didn't even exist when the installer was released. Unfortunately the installer is providing a very poor error message when you attempt that:

No Java Found NetBeans IDE cannot be installed. This software can be installed with Java 8 or newer. Please download and install the latest update of Java 8 from http://www.oracle.com/technetwork/java/javase/downloads/index.html and restart NetBeans installation.

The installer's error message is highly misleading for two reasons:

• Instead of "No Java Found" it would be more accurate if the error was "No supported version of Java found" .
• The advice "Please download and install the latest update of Java 8" makes no sense because NetBeans 13 doesn't even support the use of JDK 8.

So this looks like an issue with the NetBeans Installer rather than NetBeans or Java 18. You have a couple of workarounds:

• Run the installer using JDK 17 instead of JDK 18. Once you have NetBeans installed and running on JDK 17, you can then add JDK 18 as a second Java Platform, or edit netbeans.conf so that NetBeans will use JDK 18 instead of JDK 17 after a restart.
• Don't use the installer at all. Instead, just download the zip of NetBeans named netbeans-13-bin.zip , unzip it, and then edit netbeans.conf so that NetBeans will use JDK 18.