The Dreaded Classpath & Packages
Hi,
I'm semi new to Java (I just finished my first intro class), and to my surprise the prof. did not go into detail regarding classpaths and how to use them, blasphemy, I know. He had everyone rely on an IDE for this�
I have three problems compiling with packages.
1) I don�t use an IDE, but instead compile at the command line.
2) I am fairly new to the Mac (OS X), and don�t quite understand what the root directory is. I know on my windows machine it�s C:\, but on my Mac I�m not sure if it is User/ or something else.
3) In regards to #2, I don�t know where my import statement should start. At Users/ , or somewhere else?
Lets say I have one package called Phone.java located here:
Users/JohnSmith/JavaLibrary/packages/PhonePackage
Then I have the main program which references this package located here:
Users/JohnSmith/JavaLibrary/applications/AddressBook/address.java
How do I get the main program to compile the Phone Package? I�ve tried everything but can�t get it to work. I am assuming it�s something like javac �classpath �enter path� address.java. But I don�t know what the root should be, which throws off my claspath and my import statements.
Any help would be greatly appreciated!!!
Kevin
You need to compile both the files (Phone.java and address.java). First compile Phone.java by going to the directory:
Users/JohnSmith/JavaLibrary/packages/PhonePackage
And type in:javac -classpath . Phone.javathen go to
Users/JohnSmith/JavaLibrary/applications/AddressBook/
and type in:javac -classpath Users/JohnSmith/JavaLibrary/packages:. address.javaTo run, type:java -classpath Users/JohnSmith/JavaLibrary/packages:Users/JohnSmith/JavaLibrary/applications AddressBook.addressAll this assumes that the class Phone (contained in Phone.java) is in a package called PhonePackage and that the class address (contained in address.java) is in a a package called AddressBook.
A little nitpick: it's convention to use all lowercase letters for packages and capitalize the initial letter of each word in the name of a class. Following that rule, PhonePackage should be phonepackage, AddressBook should be addressbook and address should be Address.
ps. Not sure whether the multiple path seperator is : or ; in mac osx but since it's unix based I'm guessing it's :
Good luck.
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