/** * Compares the specified Object with the receiver. Returns true if and only if the specified * Object is also an ArrayList of the same type, both Lists have the same size, and all * corresponding pairs of elements in the two Lists are identical. In other words, two Lists are * defined to be equal if they contain the same elements in the same order. * * @param otherObj the Object to be compared for equality with the receiver. * @return true if the specified Object is equal to the receiver. */ public boolean equals(Object otherObj) { // delta // overridden for performance only. if (!(otherObj instanceof ByteArrayList)) return super.equals(otherObj); if (this == otherObj) return true; if (otherObj == null) return false; ByteArrayList other = (ByteArrayList) otherObj; if (size() != other.size()) return false; byte[] theElements = elements(); byte[] otherElements = other.elements(); for (int i = size(); --i >= 0; ) { if (theElements[i] != otherElements[i]) return false; } return true; }
/** * Removes from the receiver all elements that are contained in the specified list. Tests for * identity. * * @param other the other list. * @return <code>true</code> if the receiver changed as a result of the call. */ public boolean removeAll(AbstractByteList other) { // overridden for performance only. if (!(other instanceof ByteArrayList)) return super.removeAll(other); /* * There are two possibilities to do the thing a) use other.indexOf(...) * b) sort other, then use other.binarySearch(...) * * Let's try to figure out which one is faster. Let M=size, * N=other.size, then a) takes O(M*N) steps b) takes O(N*logN + M*logN) * steps (sorting is O(N*logN) and binarySearch is O(logN)) * * Hence, if N*logN + M*logN < M*N, we use b) otherwise we use a). */ if (other.size() == 0) { return false; } // nothing to do int limit = other.size() - 1; int j = 0; byte[] theElements = elements; int mySize = size(); double N = (double) other.size(); double M = (double) mySize; if ((N + M) * cern.jet.math.Arithmetic.log2(N) < M * N) { // it is faster to sort other before searching in it ByteArrayList sortedList = (ByteArrayList) other.clone(); sortedList.quickSort(); for (int i = 0; i < mySize; i++) { if (sortedList.binarySearchFromTo(theElements[i], 0, limit) < 0) theElements[j++] = theElements[i]; } } else { // it is faster to search in other without sorting for (int i = 0; i < mySize; i++) { if (other.indexOfFromTo(theElements[i], 0, limit) < 0) theElements[j++] = theElements[i]; } } boolean modified = (j != mySize); setSize(j); return modified; }
/** * Returns a deep copy of the receiver. * * @return a deep copy of the receiver. */ public Object clone() { // overridden for performance only. ByteArrayList clone = new ByteArrayList((byte[]) elements.clone()); clone.setSizeRaw(size); return clone; }