Map has two meanings, tools for navigating on planet earth, and tools to let you lookup Objects by key.
Geographical Maps
- Yahoo has zoomable online street maps of Canada, USA,
France, Germany, Italy, Spain and the UK, but no latitude/longitude. The maps are very buggy and crash
frequently because they rely on JavaScript and IE-specific coding. You may post dynamic links to their maps, but you may not cut and paste the results to your website. Their scheme to
generate HTML (Hypertext Markup Language) is pretty shaky. Instead, just paste the URL (Uniform Resource Locator) after you home in on the desired location.
- Mapquest Lets you enter originating and destination
address and it will generate a set of navigation instructions.
- Google:Maps lets you home in visually or by keying an
address.
- GlobeExporer.com will display a map given an
American address. It has Canadian maps too, but does not have Canadian addresses.
- Google:local lets you home in on
business listings in a given geographic location.
- worldweb: used by businesses to help customers
find them.
Java Maps
In Java, java.util.Map is the interface that Collections implement when they
are capable of looking something up by unique key.
Many classes implement it including: AbstractMap, Attributes, AuthProvider, ConcurrentHashMap,
EnumMap, HashMap, Hashtable,
IdentityHashMap, LinkedHashMap, PrinterStateReasons, Properties, Provider,
RenderingHints, TabularDataSupport, TreeMap, UIDefaults and WeakHashMap.
All Maps support put( key,
value) and get( key).
Note that Collections that look up by an int index
such as ArrayList and Vector are not considered
Maps. They are Lists.
Learning More
Oracle’s Javadoc on
Map interface : available:
Oracle’s Javadoc on
Collections.unmodifiableMap : available:
Oracle’s Javadoc on
Collections.emptyMap() : available: