js.log

Interface LogContext

All Known Implementing Classes:

DefaultLogContext

public interface LogContext

Logger context stores named diagnostic context data to current thread. Thread named diagnostic data can be injected into every log message from thread till clear() is called. These class is specifically designed for multithreaded environments and allow to separate otherwise intermixed log messages. Implementation is expected to propagate this log context on child threads, most probable using InheritableThreadLocal.

Here is an example of a hypothetical servlet. On every request, service method stores context name and remote address with app, respective ip names, on log context; every log message will include context name and remote address no matter if called directly from servlet service or from a nested method.

 private static final LogContext logContext = LogFactory.getLogContext();
 
 protected void service(HttpServletRequest httpRequest, HttpServletResponse httpResponse) {
        // store request remote address to current thread
  logContext.put("app", httpRequest.getContextPath());
  logContext.put("ip", httpRequest.getRemoteHost());
        try {
                // log message can be configured to include request remote address
                log.debug(...);
        }
        finally {
                // takes care to cleanup request remote address from current thread since thread can be reused
                logContext.clear();
        }
 }
 

Version:

final

Author:

Iulian Rotaru

Method Summary

Modifier and Type	Method and Description
void	clear() Cleanup all diagnostic data from this logger context.
void	put(String name, Object value) Put named diagnostic context data on logger related to current thread.

Method Detail

put

void put(String name,
         Object value)

Put named diagnostic context data on logger related to current thread. Diagnostic data will reside on current thread till thread terminates or clear() is called on current thread. Override value if named diagnostic data already exists.

If given name is null or empty this method silently does nothing and if value is null remove named diagnostic context data.

Parameters:

name - name for diagnostic context data, not null,

value - diagnostic context value, possible null.

clear

void clear()

Cleanup all diagnostic data from this logger context.