address : Java Glossary

address

Byte cells in physical RAM (Random Access Memory) are sequentially numbered starting at 0. The index number of a cell it called its address. At the machine code level the computer examines numbers in cells, and stores numbers in cells using their addresses to keep track of what information it keeps where. Sometime groups of cells are ganged together, e.g. 4 cells to form an int. In Intel CPUs (Central Processing Units) the low order byte comes first. This is called little-endian order. In IBM (International Business Machines) mainframes the high order bite comes first. This is called big-endian order. In either case, the first byte is considered the address of the group. Now-a-days programmers rarely get involved with addresses (usually specified as hexadecimal (base 16) numbers). Debugging and programming tools allow programers to assign easy-to-remember names to various addresses and use those instead.

Address can also refer to a mailing street address. It is formed of such things as apartment number, street number, Street name, street direction, street type (avenue/street etc.), city/town, State/Province, country and postal code. Unfortunately every country has its own format. They put the fields in different orders. The postal code is sometimes made of two parts. I have long advocated that an international street address should be treated almost like an atomic type, with the details of input, validation, printing, sorting and display (including cross checking postal code with other parts of the address) should not be the domain of application programs. I am sure this will get sorted out and perfected just as electric communication and courier services using GPS (Global Positioning System) coordinate addresses have obsoleted snail mail delivery.

AddressDoctor: information on address formats for various countries
endian
hexadecimal
RAM

CMP homejump to top

available on the web at:

http://mindprod.com/jgloss/address.html
  

optional Replicator mirror
of mindprod.com
on local hard disk J:

J:\mindprod\jgloss\address.html
logo
Please email your , letters to the editor, errors, omissions, typos, formatting errors, ambiguities, unclear wording, broken/redirected link reports, suggestions to improve this page or comments to Roedy Green : feedback email. If you want your message, your name or email kept confidential, not considered for public posting, please explicitly specify that. Unless you state otherwise, I will treat your message as a letter to the editor that I may or may not publish in the feedback section. After that, it will be too late to retract it. If you disagree with something I said, especially when sending an ad-hominem attack, a rant composed mainly of obscenities or a death threat, please quote the offending passage and cite the web page where you found it, tell me why you think it is wrong, and, if possible, provide some supporting evidence. I can’t very well fix erroneous or ambiguous text if I can’t find it.
Blog
IP:[65.110.21.43]
Your face IP:[23.20.196.179]
You are visitor number 11.