Java putting Hashmap into Treemap

java hashmap treemap
BeyondProgrammer picture BeyondProgrammer · Oct 22, 2013 · Viewed 30.4k times · Source

I am currently reading 2 million lines from a textfile as asked in the previous question Java Fastest way to read through text file with 2 million lines

Now I store these information into HashMap and I want to sort it via TreeMap because I want to use ceilingkey. Is the following method correct?

private HashMap<Integer, String> hMap = new HashMap();

private TreeMap<Integer, String> tMap = new TreeMap<Integer, String>(hMap);

Answer

Akkusativobjekt picture Akkusativobjekt · Oct 22, 2013 
HashMap<Integer, String> hashMap = new HashMap<Integer, String>();
TreeMap<Integer, String> treeMap = new TreeMap<Integer, String>();
treeMap.putAll(hashMap);

Should work anyway.

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