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Java:ConcurrentHashMap的ConcurrencyLevel值(Java: ConcurrencyLevel value for ConcurrentHashMap)
Java:ConcurrentHashMap的ConcurrencyLevel值(Java: ConcurrencyLevel value for ConcurrentHashMap)
ConcurrencyLevel是否有一些最佳值,超过该值,ConcurrentHashMap的性能开始降级?
如果是,那该值是什么,以及性能下降的原因是什么? (这个问题来源于试图找出ConcurrentHashMap可能具有的任何实际限制)。
Is there some optimal value for ConcurrencyLevel beyond which ConcurrentHashMap's performance starts degrading?
If yes, what's that value, and what's the reason for performance degradation? (this question orginates from trying to find out any practical limitations that a ConcurrentHashMap may have).
原文:https://stackoverflow.com/questions/9465636
更新时间:2022-05-27 21:05
最满意答案
您可以先将整个文件存储到字符串中,然后将其拆分:
... String whole = ""; while (x.hasNext()) { String a = x.next(); whole = whole + " " + a; } String[] array = whole.split(" "); ...
或者您可以使用
ArrayList
,这是一个“更清洁”的解决方案:... ArrayList<String> words= new ArrayList<>(); while (x.hasNext()) { String a = x.next(); words.add(a); } //get an item from the arraylist like this: String val=words.get(index); ...
You could store the whole file into a string first, then split it:
... String whole = ""; while (x.hasNext()) { String a = x.next(); whole = whole + " " + a; } String[] array = whole.split(" "); ...
Or you could use an
ArrayList
, which is a 'cleaner' solution:... ArrayList<String> words= new ArrayList<>(); while (x.hasNext()) { String a = x.next(); words.add(a); } //get an item from the arraylist like this: String val=words.get(index); ...
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