whenever i have to run a java program in the command prompt i have to set the current directory to the bin folder inside the java folder's jdk folder.i also have to save my programs in the bin folder to run them.What should i do if i have to save my programs somewhere other than the bin folder in the java folder and also run these programs from command prompt.
You have to add the bin directory of the JDK to the PATH environment variable. You can read how to do that in the JDK installation instructions, step 4 (Update the PATH variable). Note that you have to close and re-open the command prompt window after changing the variable.