I used to have JRE 7 before, and now I installed JDK 8 and deleted my JRE 7 folder. I'm using Eclipse Kepler, and I added JDK 1.8 to my installed JRE's. Can I delete the JRE 1.8 folder as it's taking up space in my computer? Will it cause any problems?
JRE is a part of JDK.
No need to have JRE when you have JDK. If you open JDK folder and see, you'll have JRE folder inside it which is the same of JRE folder initially you have.
As all have said that JDK includes JRE, that is perfectly right.
But let me add more on it to fulfill an industrial Structure.
While an employee works on some project, they need JDK for they need to write code as well as compile it.
But after the development process completes, the software is ready to deliver and the client's machine will have to choose whether JDK is needed or the JRE.
I would recommend to install JRE on clients' machines because clients don't have to compile the code. Clients always goes straight forward to execute it.
So, make sure to install JRE on clients' machines, not JDK. It will give the advantage of Memory - Utilization too.
Thanks.
You can delete JRE. JDK is a superset of JRE and contains everything already.
Related
So I'm trying to install Eclipse IDE for Java on my main pc.
I had no problem installing it on my laptop but when trying to install it on my PC I get JRE Missing webpage.
I've installed the JDK and JRE and they are both working. I could use some advice.
i also had the problem with eclipse and the JRE.
Try to delete the 2 Java versions and deinstall eclipse.
then install the JDK first and seccond the JRE. after the 2 installations install the new eclipse version(in the installer you chan choose between some installations take the first).
i hope I can help you.
Unless explicitly told in eclipse.ini Eclipse uses the system wide java command.
Easiest for you right now is to install a system wide JRE (same 32/64 bit flavor as eclipse).
I had the same issue. It was happening when installing different match of JDK version (11 in my case), with JRE (8 in my case).
So, in order to have this installation of Eclipse working make sure that you have both JDK and JRE referring to the same version. Installation will not work if they have different versions.
I have a JRE already installed on my system, but looks that I need to install JDK.
Is it possible to keep the JRE installed and install JDK also or I should to remove the JRE before.
any advice? because it should be better for me if I don't delete any old programme.
You can install JDK without uninstalling JRE. It will be ok and work fine.
BUT
You should note that JDK comes with JRE, so you no need to install it separately. Also, You can install different JDK versions (e.g. jdk1.7.0_51, jdk1.8.0_149, jdk1.8.0_151, jdk1.7.0_58) side by side and all will work fine.
So I installed the latest Java SE Development Kit (jdk1.8.0_112) that come with JRE (jre1.8.0_112) so I notice I now have two JREs one I got from java.com (jre1.8.0_111)
So what I did is I uninstalled the (jre1.8.0_111) but then when I tried to visit java.com to verify if my JRE is working it seems like it does not work. it just ask me to download it which is the version (jre1.8.0_111).
My question is does the JRE included in the SDK is for development purposes only? and is different from the JRE the end users get??
both JRE foot prints are same. only difference is additionally you get development libraries(+ JRE) with JDK(java development Kit) as opposed to standalone JRE installtion
My question is does the JRE included in the SDK is for development purposes only?
No.
and is different from the JRE the end users get??
No.
What has actually happened here is that your web browser's Java plugin apparently cannot find the previously configured Java installation anymore. The "verify" page is checking that the Java that your browser is using in its plugin is the right one.
If you don't have Java enabled in your browser (wise move!!) then it doesn't matter that it won't work (!)
If you do need the browser's Java plugin to work, the I suggest that you uninstall the JDK and reinstall it. If that fails, you will need to dig deeper to find out why the plugin is not working.
Alright, so reinstalling the SDK didn't actually solve my problem but I think I figured out what's wrong. So the JDK that I downloaded is for 64bit windows thus it includes 64bit JDK and JRE BUT the browser that I am using is 32bit! which is why it needs a 32bit JRE to run Java. So basically I need 32bit JRE for it to work on my browser.
(by default internet explorer and firefox uses 32bit regardless if u have 64bit OS, but u can freely switch to 64bit if you want but not recommended since some web content may not work properly in a 64-bit browser - got this info from this link)
I am just interested, as far as I know if you want do some Java programming, you will need to download a JDK. As part of the JDK, it comes with the JRE. However, I think most Windows OS has pre-installed JRE already. I have several questions:
Does this mean this pre-installed version will get overwritten by the freshly downloaded and installed JRE?
Does a JRE have a version e.g. JRE-7,JRE-8?
If there is version for the JRE and the pre-installed JRE gets overwritten, does that mean there is a risk that some old applications will not work anymore?
1) This depends on your installation directory choice.
2) JRE is just a runtime part of the JDK (no compilers and tools) and thus is has the same versioning scheme as JDK.
3) Java is developed in the way that guarantees backwards compatibility. However you can get incompatibility problems with tools like Maven or libraries like JAXB.
Go to the Windows control panel, click Java, click the Java tab and then View. You will see all of the versions of Java that have been installed.
I've read here that Intellj is written in java,
how then it can run without any JRE installed on the machine?
It cannot. Requirements clarifies that at least JDK 6 must be installed.
I guess some distributions might have it bundled but it is not the case for standard one version 12.
IntelliJ IDEA comes with JRE. Just look inside IDEA installation folder where you can find jre folder.