자바 기초 NCS교육과정(44)-컬렉션3

 1 배열 구조로 데이터 관리 : Vector, ArrayList
   ArrayList -추가-(순차적으로 처리할때 사용)

 2 링크로 데이터 관리 : LinkedList
   삽입, 삭제-(비순차적으로 처리할때 사용)

 

 3 List을 구현해놓은 컬렉션
   Vector,ArrayList,LinkedList은 add()해준 순서대로 데이터 관리를 해준다.

 

Java190_LinkedList.java

public class Java190_LinkedList {
 
	public static void main(String[] args) {
		ArrayList<String> aList= new ArrayList<String>();
		aList.add(new String("java"));
		aList.add(new String("jsp"));
		aList.add(new String("spring"));
		System.out.println(aList);
		System.out.println("//////////////////////");
		
		LinkedList<String> aNode = new LinkedList<String>();
		aNode.add(new String("java"));
		aNode.add(new String("jsp"));
		aNode.add(new String("spring"));
		System.out.println(aNode);
		
		//삽입
		aNode.add(1, new String("ajax"));
		System.out.println(aNode);
		
		//삭제
		aNode.remove(2);
		System.out.println(aNode);
 
	}
 
}

출력결과

 

Java191_LinkedList.java

public class Java191_LinkedList {
 
	public static void main(String[] args) {
		LinkedList<String> aNode = new LinkedList<String>();
		//추가
		aNode.add(new String("java"));
		aNode.add(new String("jsp"));
		aNode.add(new String("spring"));
		System.out.println(aNode);
		
		ListIterator<String> ite=aNode.listIterator();
		System.out.println("앞->뒤");
		while(ite.hasNext())
			System.out.println(ite.next());
 
		System.out.println("뒤->앞");
		while(ite.hasPrevious())
			System.out.println(ite.previous());
 
	}
 
}

출력결과

 

 

 

stack(스택)
  1 LIFO(Last In First Out) : 마지막에 저장된 요소를 먼저 꺼낸다.
  2 수식계산, 수식괄호검사, undo/redo, 뒤로/앞으로

 

Java192_LinkedList.java

public class Java192_LinkedList {
 
	public static void main(String[] args) {
		LinkedList<String> nStack = new LinkedList<String>();
		//추가
		nStack.push(new String("java"));
		nStack.push(new String("jsp"));
		nStack.push(new String("spring"));
 
		while (!nStack.isEmpty())
			System.out.println(nStack.pop());
 
	}
 
}

출력결과

 

 

Queue(큐)
  1. FIFO(First in First Out) : 제일 먼저 저장한 요소를 제일 먼저 꺼내온다.
  2. 최근사용문서, 인쇄작업대기목록, 버퍼

 

Java193_LinkedList.java

public class Java193_LinkedList {
 
	public static void main(String[] args) {
		LinkedList<String> nQueue=new LinkedList<String>();
		//추가
		nQueue.offer(new String("java"));
		nQueue.offer(new String("jsp"));
		nQueue.offer(new String("spring"));
		
		//
		System.out.println(nQueue.get(1));
		
		while(!nQueue.isEmpty())
			System.out.println(nQueue.poll()); //index 가능, 메모리에서 아예 지우면서 꺼냄
		
	}
 
}

출력결과