[JAVA] Array<->Vector<->HashMap<->ArrayList 변환

Array<->ArrayList 변환 ( Array -> List -> ArrayList )

	public static void main(String[] args) {
		String[] arrColors = {"white", "orange", "black"};
		List<String> lst = Arrays.asList(arrColors); // List는 인터페이스
		ArrayList<String> aLst = new ArrayList(lst);
		System.out.println("ArrayList contains"+aLst);
		
		String[] temp = aLst.toArray(new String[aLst.size()]);
		for(String t : temp)
			System.out.print(t+" ");
		
	}

 

실행 결과

 

 

Array<->Vector 방법(1)

public class Extest{
	public static void main(String[] args) {
		String[] arrColors = {"white","orange","black"};
		List<String> lst = Arrays.asList(arrColors);
		Vector<String> v = new Vector(lst);
		System.out.println("Vector contains:"+v);
		
		String[] temp = v.toArray(new String[v.size()]);
		for(String t : temp)
			System.out.print(t+" ");
	}
}

 

 

Array<->Vector 방법(2)

public class Extest{
	public static void main(String[] args) {
		String[] strColors = {"white","orange","black"};
		Vector<String> vColors = new Vector<String>();
		Collections.addAll(vColors, strColors);
		System.out.println("Vector contains: "+vColors);

		String[] temp = vColors.toArray(strColors);
		for(String t : temp)
			System.out.print(t+" ");
	}
}

 

 

HashMap의 Value -> Collection -> Array

( HashMap<String,Score> apply; )

Collection<Score> vs = apply.values(); // 예로 개인적으로 만든 Score 클래스
Score v[] = vs.toArray( new Score[apply.size()] );
for( Score x : v )
	System.out.println(x);

 

HashMap의 Value -> Collection -> ArrayList

ArrayList<Score> lst = new ArrayList<Score>( apply.values() );

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