package test.singleton;
/**
* 文件日志类
*
*/
public class FileLogger implements Logger
{
private static FileLogger logger;
private FileLogger()
{
}
public static FileLogger getFileLogger()
{
if(logger==null)
{
logger = new FileLogger();
}
return logger;
}
public synchronized void log(String msg) {
FileUtil futil = new FileUtil();
futil.writeToFile("log.txt", msg);
}
}
package test.singleton;
import java.io.BufferedWriter;
import java.io.FileWriter;
import java.io.IOException;
public class FileUtil
{
/**
* 写文件
* @param fileName
* @param message
*/
public void writeToFile(String fileName,String message)
{
try
{
BufferedWriter out = new BufferedWriter(new FileWriter(fileName,true));
out.write(message);
out.write("\n");
out.close();
}
catch (IOException e)
{
e.printStackTrace();
}
}
}
package test.singleton;
/**
* 日志接口
*
*/
public interface Logger {
/**
* 日志方法
* @param msg
*/
public void log(String msg);
}
package test.singleton;
import java.io.IOException;
import java.util.Properties;
/**
* 日志工厂类
*/
public class LoggerFactory {
/**
* 文件日志是否启用
* @return true:启用 false:未启用
*/
public boolean isFileLoggingEnabled()
{
Properties p = new Properties();
try
{
p.load(ClassLoader.getSystemResourceAsStream("logger.properties"));
String fileLoggingValue = p.getProperty("FileLogging");
if(fileLoggingValue.equalsIgnoreCase("ON")==true)
{
return true;
}
else
{
return false;
}
}
catch (IOException e) {
return false;
}
}
/**
*
* @return
*/
public Logger getLogger()
{
if(isFileLoggingEnabled())
{
return FileLogger.getFileLogger();
}
return null;
}
}
package test.singleton;
public class LoggerTest {
public static void main(String[] args)
{
LoggerFactory factory = new LoggerFactory();
Logger logger = factory.getLogger();
logger.log("Test Message to Log1");
logger.log("Test Message to Log2");
logger.log("Test Message to Log3");
}
}
FileLogging=ON
