Java Deep Copy, Shallow Copy

1. Deep copy (깊은 복사)

- 같은 내용의 새로운 객체를 생성, 원본의 변화에 복사본이 영향을 받지 않는다.

2. Shallow copy(얕은 복사)

- 참조변수만 복사, 원본의 변화에 복사본이 영향을 받는다.

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import java.util.Arrays;   public class CopyTest {     public static void main(String[] args) {         int[] data = { 0, 1, 2, 3, 4, 5 };         int[] sCopy = null;         int[] dCopy = null;           sCopy = shallowCopy(data);         dCopy = deepCopy(data);           System.out.println("Original : " + Arrays.toString(data));         System.out.println("Shallow : " + Arrays.toString(sCopy));         System.out.println("Deep : " + Arrays.toString(dCopy));         System.out.println();           data[0] = 5;         System.out.println("Original : " + Arrays.toString(data));         System.out.println("Shallow : " + Arrays.toString(sCopy));         System.out.println("Deep : " + Arrays.toString(dCopy));         System.out.println();     } // main       public static int[] shallowCopy(int[] arr) {         return arr;     } // shallowCopy       public static int[] deepCopy(int[] arr) {         if (arr == null)             return null;         int[] result = new int[arr.length];         System.arraycopy(arr, 0, result, 0, arr.length);         return result;     } // deepCopy       } // CopyTest   /*  * 결과  *  * Original : [0, 1, 2, 3, 4, 5]  * Shallow : [0, 1, 2, 3, 4, 5]  * Deep : [0, 1, 2, 3, 4, 5]  *  * Original : [5, 1, 2, 3, 4, 5]  * Shallow : [5, 1, 2, 3, 4, 5]  * Deep : [0, 1, 2, 3, 4, 5]  */

출처: http://gangzzang.tistory.com/entry/Java-Deep-Copy-Shallow-Copy