Relised list #1531
Relised list #1531
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Thank you for your hard work on this implementation! However, there are a few critical issues that need to be addressed to ensure the ArrayList functions correctly. The initial size and capacity management are incorrect, which affects several methods like add, addAll, get, set, and remove. These issues impact the core functionality of the list, such as incorrect size calculations and index validations. Please address these to meet the task requirements. Once resolved, your code will be much stronger! Keep up the great effort! 😊
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🔄 Fix the issues, commit the changes, and then re-request my review using the Re-request review button in the Reviewers tab.
| public class ArrayList<T> implements List<T> { | ||
| private Object[] array = new Object[10]; | ||
| private int size = 1; |
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The initial size is set to 1, which is incorrect. It should be initialized to 0 since the list is empty initially.
| System.arraycopy(array, 0, newArray, 0, array.length); | ||
| array = newArray; | ||
| } | ||
| array[size - 1] = value; |
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The assignment array[size - 1] = value; is incorrect. It should be array[size] = value; since size should represent the number of elements in the list, not the next available index.
| System.arraycopy(array, 0, newArray, 0, array.length); | ||
| array = newArray; | ||
| for (int i = 0; i < list.size(); i++) { | ||
| array[i + size - 1] = list.get(i); |
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The assignment array[i + size - 1] = list.get(i); is incorrect. It should be array[i + size] = list.get(i); to correctly place elements from the list being added.
| for (int i = 0; i < list.size(); i++) { | ||
| array[i + size - 1] = list.get(i); | ||
| } | ||
| size = tempSize + 1; |
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The size update size = tempSize + 1; is incorrect. It should be size = tempSize; since tempSize already accounts for the total number of elements after adding the list.
| public T get(int index) { | ||
| return null; | ||
| public T get(int index) throws ArrayListIndexOutOfBoundsException { | ||
| if (index >= size - 1 || index < 0) { |
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The condition index >= size - 1 is incorrect. It should be index >= size to correctly check if the index is within bounds.
| public void set(T value, int index) { | ||
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| public void set(T value, int index) throws ArrayListIndexOutOfBoundsException { | ||
| if (index >= size - 1 || index < 0) { |
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The condition index >= size - 1 is incorrect. It should be index >= size to correctly check if the index is within bounds.
| } | ||
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| @Override | ||
| public int size() { | ||
| return 0; | ||
| return size - 1; |
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The return statement return size - 1; is incorrect. It should be return size; since size should represent the number of elements in the list.
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Great job on your ArrayList implementation! 🎉 While there are several critical issues that need attention, such as the resizing logic in the add and addAll methods and the element shifting in the remove method, your effort is commendable. It's important to address these issues to ensure the ArrayList functions correctly.
Here are some key points to focus on:
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Resizing Logic: Ensure that the array resizes correctly when full. The condition should be
size >= array.lengthto trigger resizing at the right time. In theaddAllmethod, verify that the array can accommodate all new elements and resize accordingly. -
Element Shifting: In the
removemethod, usesize - index - 1inSystem.arraycopyto correctly shift elements and avoid out-of-bounds errors. -
Code Optimization: Extract the resizing logic into a separate method to adhere to the DRY principle, and avoid using utility classes like
Objects.equals(). -
Magic Numbers and Constants: Move hardcoded values like the initial capacity to a constant field for better readability and maintainability.
Remember, addressing these issues will not only improve your code but also enhance your understanding of data structures. Keep up the good work, and continue learning from these experiences! 🚀
✨ Please rate this review in the Platform's notification center. I will be grateful for your feedback! ✨
| @Override | ||
| public void add(T value) { | ||
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| if (size + 1 == array.length) { |
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The condition size + 1 == array.length should be size == array.length to ensure resizing occurs when the array is full, not when it's about to be full.
| if (index > size() || index < 0) { | ||
| throw new ArrayListIndexOutOfBoundsException("Index out of bounds"); | ||
| } | ||
| if (size + 1 >= array.length) { |
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The condition size + 1 >= array.length should be size >= array.length to ensure resizing occurs when the array is full.
| int summarySize = list.size() + size(); | ||
| final int tempSize = summarySize; | ||
| summarySize = summarySize + summarySize / 2; | ||
| Object[] newArray = new Object[summarySize]; | ||
| System.arraycopy(array, 0, newArray, 0, array.length); | ||
| array = newArray; |
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The resizing logic in addAll is incorrect. You should check if the current array can accommodate the new elements and resize accordingly. The calculation of summarySize is also incorrect; it should ensure the new array size is sufficient to hold all elements.
| throw new ArrayListIndexOutOfBoundsException("Index out of bounds"); | ||
| } | ||
| T result = (T) array[index]; | ||
| System.arraycopy(array, index + 1, array, index, array.length - index - 1); |
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The System.arraycopy call in remove should use size - index - 1 instead of array.length - index - 1 to correctly shift elements and avoid accessing out of bounds.
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