Introduction

2020/4/16 update The original article was quite error-prone, so I drastically corrected the article. Thank you for pointing out.

Only the part of the experience story that there was a way to find and a stumbling point when rolling the JDK in various places Please for your reference.

Also, as is well known, the Oracle JDK "It can be used free of charge for personal use and development use."

It should only be considered for commercial and associated environments.

Reference article

-Guide to switching to OpenJDK due to the charge for Oracle Java SE -Three JDKs to consider when using Java for free for commercial use

The following is a modified version of the original article

Background

When creating an in-house development environment on a Windows PC, the procedure was to install the Oracle JDK, but I heard that this time it was charged. [^ 1]

However, if you look closely at the test environment, it was OpenJDK [^ 2], so I thought about migrating Java 8 to OpenJDK on Windows. [^ 1]: The pages around here are easy to understand because they include interpretations. https://www.orangeitems.com/entry/2018/09/26/152343 [^ 2]: Since the OS on the server side uses Redhat Enterprise linux, I wonder if it is a set license form. (I haven't seen the material) https://access.redhat.com/ja/articles/1457743

Step

First from the pre-state

Environment variable --path is set to % JAVA_HOME% \ bin.

C:\>echo %JAVA_HOME%
C:\Program Files\Java\jdk1.8.0_161

--javac version

C:\>javac -version
javac 1.8.0_161

--java version

C:\>java -version
java version "1.8.0_211"
Java(TM) SE Runtime Environment (build 1.8.0_211-b12)
Java HotSpot(TM) 64-Bit Server VM (build 25.211-b12, mixed mode)

that? The version of java is different ...% JAVA_HOME% I wonder if the old settings remain because they haven't seen it ... Well, what?

Guguru for the time being

Basically, do not perform the following procedure. The reason will be described later. --apt-get yum Farewell to the environment where you can use it https://openjdk.java.net/install/

we are windows! https ://jdk.java.net/ ――Yeah, you can put the latest version, 8 where? -> https://jdk.java.net/java-se-ri/8-MR3

Install & deploy

Make an Accept License Agreement and download the zip. The oracle JDK folder was organized as shown below, so I put it here. --oracle: jdk1.8.0_161 (the one that runs when javac), jre1.8.0_211 (the one that runs when java) --open: java-se-8u40-ri (the one I want you to run when javac``java)

Path setting

javac First of all, if you change % JAVA_HOME%, you can get javac.

C:\>echo %JAVA_HOME%
C:\Program Files\Java\java-se-8u40-ri

--javac version

C:\>javac -version
javac 1.8.0_40

It's changed

java

C:\>java -version
java version "1.8.0_211"
Java(TM) SE Runtime Environment (build 1.8.0_211-b12)
Java HotSpot(TM) 64-Bit Server VM (build 25.211-b12, mixed mode)

So, it didn't change, so if you look closely at % PATH% ...

C:\ProgramData\Oracle\Java\javapath
C:\Program Files (x86)\Common Files\Oracle\Java\javapath

There was such a thing. what's this → Guguru http://ooltcloud.sakura.ne.jp/blog/201802/article_09182611.html

 C:\ProgramData\Oracle\Java\javapath directory

2018/04/24  08:54    <DIR>          .
2018/04/24  08:54    <DIR>          ..
2018/04/24  08:53           207,816 java.exe
2018/04/24  08:53           208,328 javaw.exe
2018/04/24  08:53           354,248 javaws.exe
3 files 770,392 bytes
2 directories 349,382,586,368 bytes of free space

C:\ProgramData\Oracle\Java\javapath>

 C:\Program Files (x86)\Common Files\Oracle\Java\javapath directory

2019/04/18  09:01    <DIR>          .
2019/04/18  09:01    <DIR>          ..
2019/04/18  08:59           207,736 java.exe
2019/04/18  08:59           208,248 javaw.exe
2019/04/18  08:59           354,168 javaws.exe
3 files 770,152 bytes
2 directories 349,428,879,360 bytes of free space

C:\Program Files (x86)\Common Files\Oracle\Java\javapath>

Apparently, it seems that java.exe here and there was used & it was set arbitrarily when JRE was installed. → Never delete (or lower the order in % PATH%).

C:\>java -version
openjdk version "1.8.0_40"
OpenJDK Runtime Environment (build 1.8.0_40-b25)
OpenJDK Client VM (build 25.40-b25, mixed mode)

I got it

Bad place

https://jdk.java.net/java-se-ri/8-MR3 These binaries are for reference use only!

I was ignoring what was written as big. It was inappropriate because it should be used for reference.

What to really do

For example, in this case, do you have a Red Hat license first? It was good to hear that. If not, I should have searched for the article of the ancestor. Most people should be stuck.

[JAVA] [Summary] What I noticed and did when I was told that the Oracle JDK was paid