Can I develop Java programs if I have only JRE installed?

Question

I have JRE 1.7 installed on my system. Due to some admin issues I don\'t have JDK on my system. is there any way I can develop Java programs with JRE only?

Answer 1

the answer is somehow "yes,but..."

java source code execution procedure is split into 2 steps :

1)compiling the source code into a byte-code,thus generating the .class file

2)interpreting the VM specific instructions from the .class file into native instructions

.java----javac---->.class----java---->native code

needless to mention that the "javac" , the compiler of the java source code is in not part of the JRE!

so in order to develop java programs without JDK you have to skip the first step and keep using exclusively the "java" tool,thus dealing directly with byte-code !

in some extent and if you're acquainted with the JVM internals,it's possible to write some lines of byte-code using hex or text editors and then running the .class file;but you will not go further then that specially when it comes to creating complex applications as this require super-human capabilities :that's a highly daunting task .

nevertheless,todays java frameworks almost all use direct byte-code manipulation and tools like the asm framework or javassit

javassist does not require the JDK and you can generate a class from scratch and then compile/run it

java -classpath .:javassist-x.x.jar test "some arguments"

(no need to compile classes)

but again,that is only for restricted use and in order to develop java applications you have to use some JDK... finally,you have to strive to acquire full control upon what is running in you machine;recent frameworks are resource-greedy and needs a huge amount of resources(disk space,memory...) and many tools and framworks require full control,i mean administrator right : for instance i remember that once a time borland delphi refused to start and i had to give it full access rights to start...