2017年2月23日
Java Garbage Collectors
摘要： Generational Collectors (分代收集器) GC algos optimised based on two hypotheses / observations: Most objects soon become unreachable - short lived. Referen 阅读全文
posted @ 2017-02-23 21:55 小张的练习室 阅读(347) 评论(0) 推荐(0)
Intellij Shortcuts
摘要： ctrl+shift+F : search in whole project ctrl+hover : check the field info in brief ctrl+Q : check the field info in detail ctrl+P: show the parameter i 阅读全文
posted @ 2017-02-23 17:55 小张的练习室 阅读(170) 评论(0) 推荐(0)
Linux Academy Learn Notes
摘要： Linux Essentials Certification Globbing ls ?.txt ? stands for one character while * means one or more characters ls [F]*.txt list file starting with F 阅读全文
posted @ 2017-02-23 17:48 小张的练习室 阅读(807) 评论(0) 推荐(0)
Unix Shortcuts
摘要： find . -name "*.java" -type f find all the files within a director and its sub-directory ended with .java rm *~ delete all the files ended with ~ grep 阅读全文
posted @ 2017-02-23 17:45 小张的练习室 阅读(221) 评论(0) 推荐(0)
Java Maps
摘要： HashMap 是线程不安全的，主要对于写操作来说，两个以上线程同时写入Map会被互相覆盖。线程安全指的保证对同一个map的写入操作按照顺序进行，一次只能一个线程更改。比如向HashMap里put(key, value1)有可能key对应的是其他线程同时写入的value2 HashMap的遍历有两种 阅读全文
posted @ 2017-02-23 17:26 小张的练习室 阅读(1124) 评论(0) 推荐(0)