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--- java:7 [2011/09/14 22:32]
kwon37xi
+++ java:7 [2018/10/17 17:46] (현재)
kwon37xi [ThreadLocalRandom]
@@ 줄 171: / 줄 171: @@
     }
-    public static void main(String[] args) throws NoSuchMethodException, IllegalAccessException, Throwable {
+    public static void main(String[] args) throws Throwable {
         Lookup lookup = MethodHandles.lookup();
@@ 줄 185: / 줄 185: @@
 </code>
+===== ThreadLocalRandom =====
+  * [[https://docs.oracle.com/javase/7/docs/api/java/util/Random.html|Random]]을 멀티쓰레드로 접근하면 ''synchronized'' 때문에 성능이 저하됨.
+  * 쓰레드별로 Random 객체를 따로 생성하는 [[https://docs.oracle.com/javase/7/docs/api/java/util/concurrent/ThreadLocalRandom.html|ThreadLocalRandom]]을 사용하면 된다.
+<code java>
+// 대부분 아래와 같은 형태로 사용하면 된다.
+ThreadLocalRandom.current().nextX(...)
+</code>
+  * [[http://java-performance.info/java-util-random-java-util-concurrent-threadlocalrandom-multithreaded-environments/|java.util.Random and java.util.concurrent.ThreadLocalRandom in multithreaded environments  - Java Performance Tuning Guide]]
 ===== 기타 =====
   * 모든 Reflection 관련 예외들은 [[http://download.oracle.com/javase/7/docs/api/java/lang/ReflectiveOperationException.html|java.lang.ReflectiveOperationException]]를 상속하도록 되었다.
   * [[http://download.oracle.com/javase/7/docs/api/java/lang/Byte.html#compare%28byte,%20byte%29|Byte]], [[http://download.oracle.com/javase/7/docs/api/java/lang/Character.html#compare%28char,%20char%29|Character]], [[http://download.oracle.com/javase/7/docs/api/java/lang/Short.html#compare%28short,%20short%29|Short]], [[http://download.oracle.com/javase/7/docs/api/java/lang/Integer.html#compare%28int,%20int%29|Integer]], [[http://download.oracle.com/javase/7/docs/api/java/lang/Long.html#compare%28long,%20long%29|Long]] 에 static compare(x,y) 메소드가 추가되었다. 박싱 오버헤드 없이 원시값을 비교할 수 있게 되었다.
+  * [[http://java.dzone.com/articles/jdk-7-additions-currency-class|Java 7 Currency]]
+  * [[http://weblogs.java.net/blog/fabriziogiudici/archive/2012/05/07/understanding-subtle-new-behaviours-jdk-7|Understanding subtle new behaviours of JDK 7]] - JDK 7과 AspectJ 구 버전을 사용할 경우 Bytecode Verifier에 문제가 발생할 수 있다. ''-XX:-UseSplitVerifier'' 옵션을 주면 일단 넘어갈 수 있다.
+  * [[http://java.dzone.com/articles/java-7-how-write-really-fast|Java 7: How to write really fast Java code]]
+  * [[http://java.dzone.com/articles/java-7s-support-suppressed|Java 7 Support for suppressed exceptions]]
+  * [[http://java.dzone.com/articles/java-7-complete-invokedynamic|Java 7: A complete invokedynamic example]]
+  * [[http://java.dzone.com/articles/garbage-collection-automatic|Garbage Collection with Automatic Resource Management in Java 7]]
 ===== 참조 =====
+  * [[http://www.slideshare.net/boulderjug/55-things-in-java-7|55 New Features in Java 7]]
+  * [[http://code.google.com/p/java7examples/|java7examples - Documentation and examples for new Java 7 features]]
   * [[http://java.dzone.com/articles/java-7-small-language-changes|Java 7 Small Language Changes Screencast | Javalobby]]
   * [[http://download.oracle.com/javase/7/docs/technotes/guides/language/enhancements.html#javase7|Java Programming Language Enhancements]]
   * [[http://blogs.oracle.com/darcy/entry/jdk_7_library_treats|JDK 7: Small Library Treats (Joseph D. Darcy's Oracle Weblog)]]
   * [[http://jaxenter.com/java-7-the-top-8-features-37156.html|Java 7: The Top 8 Features]]
+  * [[http://www.hanb.co.kr/network/view.html?bi_id=1780|[한빛 네트워크] Java 7의 새로운 특징 : Java7에서의 중요한 변화들과 업데이트된 항목에 대한 조사.]]
+  * [[http://java.dzone.com/articles/java-7-understanding-phaser|Java 7: Understanding the Phaser]]

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