Java's ArrayList cannot be duplicated, using HashSet

ArrayList can only use the Contains method to judge all objects that are read into memory at once, thus removing duplicates.

list<string> seqId = new arraylist<string> (); for (int i = 0; i < alllines.length; i++) {string[            ] Eachline = Alllines[i].split ("[\ t]");            System.out.println (Eachline[0]);            if (!seqid.contains (eachline[0))) {Seqid.add (eachline[0]); }}

HashSet can remove repetition;

And to specify the object type,

hashset<string> seqidset = new hashset<string> ();iterator<string> IdS = Seqidset.iterator (); while (            Ids.hasnext ()) {String tmpid = Ids.next ();            string tmp = new string (tmpid);            String Eachidinset = tmp.substring (0,tmp.indexof ("."));            System.out.println ("..." +eachidinset); System.out.println (Eachidinset);}

And iterator can only generate one iteration object and cannot be reused.

iterator<string> IdS = Seqidset.iterator (); This sentence if you do not specify a <String> object of this type, the following String tmpid = Ids.next (); will be changed to Object tmpid = Ids.next ();

The Java classes you need to import are as follows:

/** import java.io.file;import java.io.fileinputstream;import java.io.filereader;import Java.io.IOException;import Java.io.bufferedreader;import Java.util.Scanner; */import java.util.iterator;import java.util.hashmap;import Java.util.set;import java.util.HashSet;import Java.util.arraylist;import java.util.List;

This article is from the "R Language Learning history" blog, please be sure to keep this source http://matrix6ro.blog.51cto.com/1746429/1773312

Java's ArrayList cannot be duplicated, using HashSet