4日目奇数と偶数の前に配列順序を調整

/**
 *   14  
 *  
 *  2014-1-18
 */
public class ReorderArray {
	
	public int[] reorderArray(int[] arr) {
		if (arr == null || arr.length <= 0) {
			throw new NullPointerException();
		}
		
		int left = 0;
		int right = arr.length - 1;
		while (left < right) {
			//  
			while (left < arr.length && !moveToLeft(arr[left])) {
				left++;
			}
			while (right >= 0 && moveToLeft(arr[right])) {
				right--;
			}
			if (left < right) {
				swap(arr, left, right);
				left++;
				right--;
			}
			
		}
		
		return arr;
	}
	
	public boolean equal(int[] arr1, int[] arr2) {
		for (int i = 0; i < arr1.length; i++) {
			if (arr1[i] != arr2[i]) {
				return false;
			}
		}
		return true;
	}
	
	/**
	 *  ， ， 
	 * 
	 * @param value
	 * @return
	 */
	private boolean moveToLeft(int value) {
		return (value & 0x1) == 0;
	}
	
	private void swap(int[] arr, int indexOne, int indexTwo) {
		int temp = arr[indexOne];
		arr[indexOne] = arr[indexTwo];
		arr[indexTwo] = temp;
	}
	
	

	public static void main(String[] args) {
		
		boolean flag = true;
		ReorderArray reorderArray = new ReorderArray();
		
		//  
		int[] arr1 = {1};
		int[] result1 = {1};
		reorderArray.reorderArray(arr1);
		flag &= reorderArray.equal(arr1, result1);

		//  
		int[] arr2 = {1, 1, 1, 1};
		int[] result2 = {1, 1, 1, 1};
		reorderArray.reorderArray(arr2);
		flag &= reorderArray.equal(arr2, result2);
		
		//  
		int[] arr3 = {8, 8, 8};
		int[] result3 = {8, 8, 8};
		reorderArray.reorderArray(arr3);
		flag &= reorderArray.equal(arr3, result3);
		
		//  
		int[] arr4 = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10};
		int[] result4 = {1, 9, 3, 7, 5, 6, 4, 8, 2, 10};
		reorderArray.reorderArray(arr4);
		flag &= reorderArray.equal(arr4, result4);
		
		//  
		boolean tryFlag = false;
		try {
			reorderArray.reorderArray(null);
		} catch (NullPointerException e) {
			tryFlag = true;
		} finally {
			//  
			flag = tryFlag;
		}
		
		
		System.out.println(flag);
	}

}