This class represents the simplest form of a string to string map. It has a benefit over a map in that it can create the result on demand based on the key.
For example, it would be possible to implement a lookup that used the key as a primary key, and looked up the value on demand from the database.
Like BiFunction is a variant of Function, this BiStringLookup is a variant of
StringLookup.
| Modifier and Type | Method and Description |
|---|---|
| public default String |
| lookup | back to summary |
|---|---|
| public default String lookup(final String key, final U object) Looks up a String key to provide a String value. The internal implementation may use any mechanism to return the value. The simplest implementation is to use a Map. However, virtually any implementation is possible. For example, it would be possible to implement a lookup that used the key as a primary key, and looked up the value on demand from the database Or, a numeric based implementation could be created that treats the key as an integer, increments the value and return the result as a string - converting 1 to 2, 15 to 16 etc. This method always returns a String, regardless of the underlying data, by converting it as necessary. For example:
Map<String, Object> map = new HashMap<String, Object>();
map.put("number", Integer.valueOf(2));
assertEquals("2", StringLookupFactory.biFunctionStringLookup(map).lookup("number", "A context object"));
| |