org.apache.logging.log4j.core.lookup
Class WebLookup

java.lang.Object
  extended by org.apache.logging.log4j.core.lookup.WebLookup
All Implemented Interfaces:
StrLookup

public class WebLookup
extends Object
implements StrLookup


Constructor Summary
WebLookup()
           
 
Method Summary
protected  javax.servlet.ServletContext getServletContext()
           
 String lookup(LogEvent event, String key)
          Looks up a String key to a String value possibly using the current LogEvent.
 String lookup(String key)
          Looks up a String key to a String value.
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

WebLookup

public WebLookup()
Method Detail

getServletContext

protected javax.servlet.ServletContext getServletContext()

lookup

public String lookup(String key)
Description copied from interface: StrLookup
Looks up a String key to 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.

The StrLookup.lookup(String) method always returns a String, regardless of the underlying data, by converting it as necessary. For example:

 Map map = new HashMap();
 map.put("number", new Integer(2));
 assertEquals("2", StrLookup.mapLookup(map).lookup("number"));
 

Specified by:
lookup in interface StrLookup
Parameters:
key - the key to be looked up, may be null
Returns:
the matching value, null if no match

lookup

public String lookup(LogEvent event,
                     String key)
Description copied from interface: StrLookup
Looks up a String key to a String value possibly using the current LogEvent.

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.

The StrLookup.lookup(String) method always returns a String, regardless of the underlying data, by converting it as necessary. For example:

 Map map = new HashMap();
 map.put("number", new Integer(2));
 assertEquals("2", StrLookup.mapLookup(map).lookup("number"));
 

Specified by:
lookup in interface StrLookup
Parameters:
event - The current LogEvent.
key - the key to be looked up, may be null
Returns:
the matching value, null if no match


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