【java8】配列を区切り文字列に変換する

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import java.util.*;
import java.util.stream.Collectors;
import java.util.stream.*;

public class Main {
    public static void main(String[] args) throws Exception {

        String []stringArray = {"aaa", "bbb", "cccc" };

         // 文字列配列をstreamに変換
         Stream<String> stringStream = Arrays.stream(stringArray);

         //streamから区切り文字列に変換
         String joined1 = stringStream.collect(Collectors.joining(","));

        //一文で書くパターン  
        String joined2 = Arrays.stream(stringArray).collect(Collectors.joining(","));

        System.out.println(joined1);
        System.out.println(joined2);

    }
}
// 実行結果
// aaa,bbb,cccc

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import java.util.*;
import java.util.stream.Collectors;
import java.util.stream.*;

public class Main {
    public static void main(String[] args) throws Exception {

        String []stringArray = {"aaa", "bbb", "cccc" };

        // 配列からListへ変換
        List<String>stringList = Arrays.asList(stringArray);

        // Listから区切り文字列へ
        String joined3 = stringList.stream().collect(Collectors.joining(":"));

        // 1文で書く
        String joined4 = Arrays.asList(stringArray).stream().collect(Collectors.joining(":"));

        System.out.println(joined3);
        System.out.println(joined4);

    }
}
// 実行結果
// aaa:bbb:cccc