在同一目录中使用java.exe运行Java程序，而无需安装

Question

I know there are lots of posts similar to this, but all of their answers require creating an .exe file. I want to know how to run a program in a folder without installing java.

I don't want to install Java 8 as it breaks some of my programs. I want to run a java program in a folder using a start.bat file that points to the java.exe file in the same directory. Like this:

"java.exe" -jar program.jar

The error is like this:

Error: Registry key 'Software\JavaSoft\Java Runtime Environment'\CurrentVersion'

has value '1.7', but '1.8' is required.
Error: could not find java.dll
Error: Could not find Java SE Runtime Environment.

Since the command window is opened in the same directory, "java.exe" should point to the java runtime.

Can I maybe copy java.dll to the directory to make it work? How can I do this without installing java 8? Could I use java ME?

Answer 1

Why don't you create a .bat file that declares a new JAVA_HOME and appends to the PATH just for this DOS/batch session, then you can point to a place where you have the required JRE (however, you kind of have to install it... it's a Windows thing).

I understand you are reluctant to install the JDK/JRE 8 on your Windows because of this: "I don't want to install Java 8 as it breaks some of my programs". But trust me, you can always change the JRE version on the Java Control Panel (windows >> control panel >> Java) and change the JAVA_HOME & PATH environment variables, you might have problems with your browser's plugins though, the Java install will affect them as well.. I guess, in that, case you can either try to skip this part of the install process or.. install JDK 7 again afterwards?

IF you just want to run this program, you can also install VirtualBox and create a VM with windows and install the JDK8 there, avoiding any problems in your OS.