如何爲log4j編寫LogFactory？

Question

我一直在訓練自己的日誌記錄。我使用log4j庫進行日誌記錄，並且我是新設計模式。我想問的是如何創建一個工廠來獲取配置的記錄器？

Answer 1

這可能對你有幫助。

public class LogFactory { 

public static final String TOOLKIT = "logging.toolkit"; 
public static final String TOOLKITCLASS = "logging.toolkit.class"; 
public static final String Log4j = "log4j"; 

public static LogAdapter logAdapter; 
public static Object lock = new Object(); 

/** 
* Get specific Log implementation 
* @param name 
* @return 
*/ 
public static Log getLog(final String name) { 

    if (logAdapter == null) { 

     synchronized (lock) { 

      String toolkitClass = System.getProperty(TOOLKITCLASS); 

      if (toolkitClass != null) { 
       System.out.println("\n Logging toolkitClass:" + toolkitClass + "\n\n"); 
       logAdapter = createObject(toolkitClass); 
      } 
      else { 
       String toolkit = System.getProperty(TOOLKIT); 
       if (toolkit == null) { 
        toolkit = Log4j; 
       } 
       if (toolkit.equalsIgnoreCase(Log4j)) { 
        logAdapter = new Log4jAdapter(); 
       } 
      } 

      //Initialize adapter 
      logAdapter.init(); 
     } 
    } 

    return logAdapter.getLog(name); 
} 


public static Log getLog(final Class<?> clazz) { 

    return LogFactory.getLog(clazz.getName()); 
} 


/** 
* Create an instance of wrapper class using reflection 
* @param className 
* @return 
*/ 
private static LogAdapter createObject(final String className) { 

    Object o = null; 

    try { 
     Class<?> cl = Class.forName(className); 
     Constructor<?> c = cl.getConstructor(); 
     o = c.newInstance(); 
    } 
    catch (Exception e) { 
     e.printStackTrace(); 
    } 
    return (LogAdapter) o; 
} 

}