Book VIII 1 in Java

Creation PDF 417 in Java Book VIII 1

Most hosting services use Linux or Unix These operating systems have a more sophisticated file permission mechanism than the Windows file system does At some point, you may need to manipulate file permissions Essentially, the universe is divided into three populations: Yourself, your group, and everybody else You can allow each group to have different kinds of permission for each file Each of the permissions is a Boolean (true or false) value:

Permissions are typically treated as binary numbers: 111 means read, write, execute This (111 value) is also a 7 permission because 111 binary translates to 7 in base ten (or base eight, but let s skip that detail for now) A permission is read as three digits, each one a number indicating the permissions, so 644 permission means rw- r-- r-- This example can be translated as The owner should be able to read and write this file Everyone else can read it Nobody can execute it If you don t understand this concept, don t worry about it The guidelines are very simple: Make sure that each of your files has 644 permission and that each directory has 755 permission That s all you really need to know

Read permission: The file can be read Typically, you want everybody to be able to read your files, or else you wouldn t put them on the Web server Write permission: The file can be written, changed, and deleted Obviously, only you should have the ability to write to your files Execute permission: Indicates that the file is an executable program or a directory that can be passed through Normally, none of your files is considered executable, although all your directories are

Most of the work is done on a local machine and then sent to the server in a big batch (That s how I did everything in this book) The standard Webbased file management tools are pretty frustrating when you want to efficiently upload a large number of files Fortunately, most hosts have the FTP (File Transfer Protocol) system available FTP is a client/server mechanism for transferring files efficiently To use it, you may have to configure some sort of FTP server on the host to find out which settings, username, and password you should use Figure 1-10 shows the Free Hostia Control Panel with this information displayed You also need an FTP client Fortunately, many free clients are available I like FireFTP, for a number of reasons: It s free and open source That s always a bonus It works as a Firefox plugin I always know where it is It s easy to use It feels just like a file manager Figure 1-11 shows FireFTP running in my browser

If you want to connect to your server with FTP, follow these steps:

You may have to dig around in the server documentation, but you should find the server name, username, and password to access your server Sometimes, you have to configure these elements yourself

Use the Manage Accounts feature to create a profile using the FTP settings Figure 1-12 shows a profile for my aharrisbooks account

FTP programs look a lot like the Windows Explorer you might have on your machine, except that they usually have two file panels The left panel represents the files on your local system, and the right panel shows files on the remote system

If you want to move a file from the local system to the remote one, use the two file explorers to find the appropriate directory on each system

It usually takes some time to transfer a large number of files Be sure the transfer is complete before you close the FTP window