增加slf4j日志实现

src/main/java/com/alibaba/druid/support/logging/LogFactory.java

@@ -26,6 +26,7 @@ public class LogFactory {
         // TODO add slf4j logging
 
         // 优先选择log4j,而非Apache Common Logging. 因为后者无法设置真实Log调用者的信息
+		tryImplementation("org.slf4j.Logger", "com.alibaba.druid.support.logging.SLF4JImpl");
         tryImplementation("org.apache.log4j.Logger", "com.alibaba.druid.support.logging.Log4jImpl");
         tryImplementation("java.util.logging.Logger", "com.alibaba.druid.support.logging.Jdk14LoggingImpl");
         tryImplementation("org.apache.commons.logging.LogFactory",

src/main/java/com/alibaba/druid/support/logging/SLF4JImpl.java

@@ -0,0 +1,105 @@
+package com.alibaba.druid.support.logging;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.slf4j.spi.LocationAwareLogger;
+
+public class SLF4JImpl implements Log {
+	private static final String callerFQCN = SLF4JImpl.class.getName();
+	private static final Logger testLogger = LoggerFactory.getLogger(SLF4JImpl.class);
+	static {
+		//if the logger is not a LocationAwareLogger instance, it can not get correct stack StackTraceElement
+		//so ignore this implementation.
+		if (!(testLogger instanceof LocationAwareLogger)) {
+			throw new UnsupportedOperationException(testLogger.getClass()+" is not a suitable logger");
+		}
+	}
+	private int errorCount;
+	private int warnCount;
+	private int infoCount;
+	private LocationAwareLogger log;
+	
+	public SLF4JImpl(Class<?> clazz) {
+		Logger log = LoggerFactory.getLogger(clazz);
+		if (log instanceof LocationAwareLogger) {
+			this.log = (LocationAwareLogger) log;
+		}
+	}
+	
+	@Override
+	public boolean isDebugEnabled() {
+		return log.isDebugEnabled();
+	}
+	
+	@Override
+	public void error(String msg, Throwable e) {
+		log.log(null, callerFQCN, LocationAwareLogger.ERROR_INT, msg, null, e);
+		errorCount++;
+	}
+	
+	@Override
+	public void error(String msg) {
+		log.log(null, callerFQCN, LocationAwareLogger.ERROR_INT, msg, null, null);
+		errorCount++;
+	}
+	
+	@Override
+	public boolean isInfoEnabled() {
+		return log.isInfoEnabled();
+	}
+	
+	@Override
+	public void info(String msg) {
+		infoCount++;
+	}
+	
+	@Override
+	public void debug(String msg) {
+		log.log(null, callerFQCN, LocationAwareLogger.DEBUG_INT, msg, null, null);
+	}
+	
+	@Override
+	public void debug(String msg, Throwable e) {
+		log.log(null, callerFQCN, LocationAwareLogger.ERROR_INT, msg, null, e);
+	}
+	
+	@Override
+	public boolean isWarnEnabled() {
+		return log.isWarnEnabled();
+	}
+	
+	@Override
+	public void warn(String msg) {
+		log.log(null, callerFQCN, LocationAwareLogger.WARN_INT, msg, null, null);
+		warnCount++;
+	}
+	
+	@Override
+	public void warn(String msg, Throwable e) {
+		log.log(null, callerFQCN, LocationAwareLogger.WARN_INT, msg, null, e);
+		warnCount++;
+	}
+	
+	@Override
+	public int getErrorCount() {
+		return errorCount;
+	}
+	
+	@Override
+	public int getWarnCount() {
+		return warnCount;
+	}
+	
+	@Override
+	public int getInfoCount() {
+		return infoCount;
+	}
+	
+	@Override
+	public void resetStat() {
+		errorCount = 0;
+		warnCount = 0;
+		infoCount = 0;
+	}
+	
+}