+
+ /**
+ * Method (copied from put) added for Jalview to efficiently increment a key's
+ * value if present, else add it with the given value. This avoids a double
+ * binary search (once to get the value, again to put the updated value).
+ *
+ * @param key
+ * @oparam toAdd
+ * @return the new value of the count for the key
+ * @throw ArithmeticException if the result would exceed the maximum value of
+ * an int
+ */
+ public int add(int key, int toAdd)
+ {
+ int newValue = toAdd;
+ int i = ContainerHelpers.binarySearch(mKeys, mSize, key);
+ if (i >= 0)
+ {
+ checkOverflow(mValues[i], toAdd);
+ mValues[i] += toAdd;
+ newValue = mValues[i];
+ }
+ else
+ {
+ i = ~i;
+ if (mSize >= mKeys.length)
+ {
+ int n = idealIntArraySize(mSize + 1);
+ int[] nkeys = new int[n];
+ int[] nvalues = new int[n];
+ System.arraycopy(mKeys, 0, nkeys, 0, mKeys.length);
+ System.arraycopy(mValues, 0, nvalues, 0, mValues.length);
+ mKeys = nkeys;
+ mValues = nvalues;
+ }
+ if (mSize - i != 0)
+ {
+ System.arraycopy(mKeys, i, mKeys, i + 1, mSize - i);
+ System.arraycopy(mValues, i, mValues, i + 1, mSize - i);
+ }
+ mKeys[i] = key;
+ mValues[i] = toAdd;
+ mSize++;
+ }
+ return newValue;
+ }
+
+ /**
+ * Throws ArithmeticException if adding addend to value would exceed the range
+ * of int
+ *
+ * @param value
+ * @param addend
+ */
+ static void checkOverflow(int value, int addend)
+ {
+ /*
+ * test cases being careful to avoid overflow while testing!
+ */
+ if (addend > 0)
+ {
+ if (value > 0 && Integer.MAX_VALUE - value < addend)
+ {
+ throw new ArithmeticException(
+ "Integer overflow adding " + addend + " to " + value);
+ }
+ }
+ else if (addend < 0)
+ {
+ if (value < 0 && Integer.MIN_VALUE - value > addend)
+ {
+ throw new ArithmeticException(
+ "Integer underflow adding " + addend + " to " + value);
+ }
+ }
+ }