JavaのHashMap使用例
HashMapSample.java を用意します。空だったら追加、すでにあったら、WordListのcntを1増加。
public class HashMapSample {
private HashMap<String, WordInfo> map = new HashMap<String, WordInfo>();
class WordInfo {
int cnt = 0;
String basicString;
public String toString() {
return cnt + " " + basicString;
}
}
public void exec() {
String[] ss = {"Java", "Ruby", "Java", "JavaScript"};
for (String s : ss) {
WordInfo wi = map.get(s);
if (wi == null) {
wi = new WordInfo();
wi.cnt = 1;
wi.basicString = s;
map.put(s, wi);
} else {
wi.cnt++;
}
}
for (String s: map.keySet()) {
WordInfo wordInfo = map.get(s);
System.out.println(s + ":" + wordInfo);
}
}
public static void main(String[] args) {
HashMapSample app = new HashMapSample();
app.exec();
}
}
実行結果は次の通り。
Ruby:1 Ruby
JavaScript:1 JavaScript
Java:2 Java