In the Java install directory, why are there multiple java.exe files?

Question

Just curious about the directory layout for the JDK . So there are two separate java.exe files - one is in:

C:\Program Files (x86)\Java\jdk1.7.0_45\bin

and one is in:

C:\Program Files (x86)\Java\jdk1.7.0_45\jre\bin

Why does there need to be two files ? The motivation for this question arises from some challenge I'm having installing a program(SQL Developer).

Answer 1

Here a link to the official Oracle documentation.

The binaries in jdk/bin and jdk/jre/bin are identical. According to the documentation, the PATH should point to jdk/bin.

Answer 2

There's a difference between installing the jdk vs. the jre.

The jdk package is the developer package and includes tools such as the compiler (javac).

The jre package is the core runtime package, and includes the JVM / runtime environment / whatever you need to run software written in JVM languages.