Update

src/java_common/Common_Bool.java

@@ -0,0 +1,10 @@
+package java_common;
+
+/**
+ * true and false
+ * @author ÌÆÁú
+ */
+public class Common_Bool {
+	public final static boolean TRUE = true;
+	public final static boolean FALSE = false;
+}

src/java_common/TimeNow.java

@@ -1,15 +1,16 @@
-/**
- * 获取系统当前时间
- * 以yyyy-MM-dd HH:mm:ss格式返回
- */
-
 package java_common;
 
 import java.text.SimpleDateFormat;
 import java.util.Date;
 
+/**
+ * 获取系统当前时间
+ * 以yyyy-MM-dd HH:mm:ss格式返回
+ * @author 唐龙
+ */
 public class TimeNow {
-	public static String getTimeNow(){
+	public static final String TIME_NOW = getTimeNow();
+	private static String getTimeNow(){
 		SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
 		return sdf.format(new Date());
 	}

src/java_thread/PrintLog.java

@@ -5,6 +5,6 @@
 public class PrintLog {
 	//´òÓ¡µ±Ç°Ê±¼äϵÄÐÅÏ¢
 	public static void log(String msg) {
-		System.out.printf("%s %s %s%n", TimeNow.getTimeNow(), Thread.currentThread().getName(), msg);
+		System.out.printf("%s %s %s%n", TimeNow.TIME_NOW, Thread.currentThread().getName(), msg);
 	}
-}
+}