@Plugin(name="main", category="Lookup") public class MainMapLookup extends MapLookup
|Constructor and Description|
Constructor when used directly as a plugin.
|Modifier and Type||Method and Description|
Looks up a String key to a String value possibly using the current LogEvent.
Looks up a String key to a String value using the map.
public MainMapLookup(Map<String,String> map)
public static void setMainArguments(String... args)
public static main(String)method calls this method to make its main arguments available for lookup with the prefix
The map provides two kinds of access: First by index, starting at
"1" and so on. For
example, the command line
--file path/file.txt -x 2 can be accessed from a configuration file with:
Second using the argument at position n as the key to access the value at n+1.
Note: Many applications use leading dashes to identify command arguments. Specifying
would result in the lookup failing because it would look for a variable named "main" with a default
value of "-file". To avoid this the ":" separating the Lookup name from the key must be followed by
a backslash as an escape character.
args- An application's
public static main(String)arguments.
public String lookup(LogEvent event, String key)
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", new Integer(2)); assertEquals("2", StrLookup.mapLookup(map).lookup("number"));
public String lookup(String key)
If the map is null, then null is returned. The map result object is converted to a string using toString().
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