02 2017 档案
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
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
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
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
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