Java Code Examples for java.util.function.IntBinaryOperator#applyAsInt()

@Test(dataProvider="intSet")
public void testParallelPrefixForInt(int[] data, int fromIndex, int toIndex, IntBinaryOperator op) {
    int[] sequentialResult = data.clone();
    for (int index = fromIndex + 1; index < toIndex; index++) {
        sequentialResult[index ] = op.applyAsInt(sequentialResult[index  - 1], sequentialResult[index]);
    }

    int[] parallelResult = data.clone();
    Arrays.parallelPrefix(parallelResult, fromIndex, toIndex, op);
    assertEquals(parallelResult, sequentialResult);

    int[] parallelRangeResult = Arrays.copyOfRange(data, fromIndex, toIndex);
    Arrays.parallelPrefix(parallelRangeResult, op);
    assertEquals(parallelRangeResult, Arrays.copyOfRange(sequentialResult, fromIndex, toIndex));
}
 

@Test(dataProvider="intSet")
public void testParallelPrefixForInt(int[] data, int fromIndex, int toIndex, IntBinaryOperator op) {
    int[] sequentialResult = data.clone();
    for (int index = fromIndex + 1; index < toIndex; index++) {
        sequentialResult[index ] = op.applyAsInt(sequentialResult[index  - 1], sequentialResult[index]);
    }

    int[] parallelResult = data.clone();
    Arrays.parallelPrefix(parallelResult, fromIndex, toIndex, op);
    assertEquals(parallelResult, sequentialResult);

    int[] parallelRangeResult = Arrays.copyOfRange(data, fromIndex, toIndex);
    Arrays.parallelPrefix(parallelRangeResult, op);
    assertEquals(parallelRangeResult, Arrays.copyOfRange(sequentialResult, fromIndex, toIndex));
}
 

/**
 * Constructs a {@code TerminalOp} that implements a functional reduce on
 * {@code int} values.
 *
 * @param identity the identity for the combining function
 * @param operator the combining function
 * @return a {@code TerminalOp} implementing the reduction
 */
public static TerminalOp<Integer, Integer>
makeInt(int identity, IntBinaryOperator operator) {
    Objects.requireNonNull(operator);
    class ReducingSink
            implements AccumulatingSink<Integer, Integer, ReducingSink>, Sink.OfInt {
        private int state;

        @Override
        public void begin(long size) {
            state = identity;
        }

        @Override
        public void accept(int t) {
            state = operator.applyAsInt(state, t);
        }

        @Override
        public Integer get() {
            return state;
        }

        @Override
        public void combine(ReducingSink other) {
            accept(other.state);
        }
    }
    return new ReduceOp<Integer, Integer, ReducingSink>(StreamShape.INT_VALUE) {
        @Override
        public ReducingSink makeSink() {
            return new ReducingSink();
        }
    };
}
 

/**
 * Constructs a {@code TerminalOp} that implements a functional reduce on
 * {@code int} values.
 *
 * @param identity the identity for the combining function
 * @param operator the combining function
 * @return a {@code TerminalOp} implementing the reduction
 */
public static TerminalOp<Integer, Integer>
makeInt(int identity, IntBinaryOperator operator) {
    Objects.requireNonNull(operator);
    class ReducingSink
            implements AccumulatingSink<Integer, Integer, ReducingSink>, Sink.OfInt {
        private int state;

        @Override
        public void begin(long size) {
            state = identity;
        }

        @Override
        public void accept(int t) {
            state = operator.applyAsInt(state, t);
        }

        @Override
        public Integer get() {
            return state;
        }

        @Override
        public void combine(ReducingSink other) {
            accept(other.state);
        }
    }
    return new ReduceOp<Integer, Integer, ReducingSink>(StreamShape.INT_VALUE) {
        @Override
        public ReducingSink makeSink() {
            return new ReducingSink();
        }
    };
}
 

/**
 * Constructs a {@code TerminalOp} that implements a functional reduce on
 * {@code int} values, producing an optional integer result.
 *
 * @param operator the combining function
 * @return a {@code TerminalOp} implementing the reduction
 */
public static TerminalOp<Integer, OptionalInt>
makeInt(IntBinaryOperator operator) {
    Objects.requireNonNull(operator);
    class ReducingSink
            implements AccumulatingSink<Integer, OptionalInt, ReducingSink>, Sink.OfInt {
        private boolean empty;
        private int state;

        public void begin(long size) {
            empty = true;
            state = 0;
        }

        @Override
        public void accept(int t) {
            if (empty) {
                empty = false;
                state = t;
            }
            else {
                state = operator.applyAsInt(state, t);
            }
        }

        @Override
        public OptionalInt get() {
            return empty ? OptionalInt.empty() : OptionalInt.of(state);
        }

        @Override
        public void combine(ReducingSink other) {
            if (!other.empty)
                accept(other.state);
        }
    }
    return new ReduceOp<Integer, OptionalInt, ReducingSink>(StreamShape.INT_VALUE) {
        @Override
        public ReducingSink makeSink() {
            return new ReducingSink();
        }
    };
}
 

/**
 * Constructs a {@code TerminalOp} that implements a functional reduce on
 * {@code int} values, producing an optional integer result.
 *
 * @param operator the combining function
 * @return a {@code TerminalOp} implementing the reduction
 */
public static TerminalOp<Integer, OptionalInt>
makeInt(IntBinaryOperator operator) {
    Objects.requireNonNull(operator);
    class ReducingSink
            implements AccumulatingSink<Integer, OptionalInt, ReducingSink>, Sink.OfInt {
        private boolean empty;
        private int state;

        public void begin(long size) {
            empty = true;
            state = 0;
        }

        @Override
        public void accept(int t) {
            if (empty) {
                empty = false;
                state = t;
            }
            else {
                state = operator.applyAsInt(state, t);
            }
        }

        @Override
        public OptionalInt get() {
            return empty ? OptionalInt.empty() : OptionalInt.of(state);
        }

        @Override
        public void combine(ReducingSink other) {
            if (!other.empty)
                accept(other.state);
        }
    }
    return new ReduceOp<Integer, OptionalInt, ReducingSink>(StreamShape.INT_VALUE) {
        @Override
        public ReducingSink makeSink() {
            return new ReducingSink();
        }
    };
}
 

/**
 * Constructs a {@code TerminalOp} that implements a functional reduce on
 * {@code int} values, producing an optional integer result.
 *
 * @param operator the combining function
 * @return a {@code TerminalOp} implementing the reduction
 */
public static TerminalOp<Integer, OptionalInt>
makeInt(IntBinaryOperator operator) {
    Objects.requireNonNull(operator);
    class ReducingSink
            implements AccumulatingSink<Integer, OptionalInt, ReducingSink>, Sink.OfInt {
        private boolean empty;
        private int state;

        public void begin(long size) {
            empty = true;
            state = 0;
        }

        @Override
        public void accept(int t) {
            if (empty) {
                empty = false;
                state = t;
            }
            else {
                state = operator.applyAsInt(state, t);
            }
        }

        @Override
        public OptionalInt get() {
            return empty ? OptionalInt.empty() : OptionalInt.of(state);
        }

        @Override
        public void combine(ReducingSink other) {
            if (!other.empty)
                accept(other.state);
        }
    }
    return new ReduceOp<Integer, OptionalInt, ReducingSink>(StreamShape.INT_VALUE) {
        @Override
        public ReducingSink makeSink() {
            return new ReducingSink();
        }
    };
}
 

/**
 * Constructs a {@code TerminalOp} that implements a functional reduce on
 * {@code int} values, producing an optional integer result.
 *
 * @param operator the combining function
 * @return a {@code TerminalOp} implementing the reduction
 */
public static TerminalOp<Integer, OptionalInt>
makeInt(IntBinaryOperator operator) {
    Objects.requireNonNull(operator);
    class ReducingSink
            implements AccumulatingSink<Integer, OptionalInt, ReducingSink>, Sink.OfInt {
        private boolean empty;
        private int state;

        public void begin(long size) {
            empty = true;
            state = 0;
        }

        @Override
        public void accept(int t) {
            if (empty) {
                empty = false;
                state = t;
            }
            else {
                state = operator.applyAsInt(state, t);
            }
        }

        @Override
        public OptionalInt get() {
            return empty ? OptionalInt.empty() : OptionalInt.of(state);
        }

        @Override
        public void combine(ReducingSink other) {
            if (!other.empty)
                accept(other.state);
        }
    }
    return new ReduceOp<Integer, OptionalInt, ReducingSink>(StreamShape.INT_VALUE) {
        @Override
        public ReducingSink makeSink() {
            return new ReducingSink();
        }
    };
}
 

/**
 * Atomically updates the field of the given object managed by this
 * updater with the results of applying the given function to the
 * current and given values, returning the updated value. The
 * function should be side-effect-free, since it may be re-applied
 * when attempted updates fail due to contention among threads.  The
 * function is applied with the current value as its first argument,
 * and the given update as the second argument.
 *
 * @param obj An object whose field to get and set
 * @param x the update value
 * @param accumulatorFunction a side-effect-free function of two arguments
 * @return the updated value
 * @since 1.8
 */
public final int accumulateAndGet(T obj, int x,
                                  IntBinaryOperator accumulatorFunction) {
    int prev, next;
    do {
        prev = get(obj);
        next = accumulatorFunction.applyAsInt(prev, x);
    } while (!compareAndSet(obj, prev, next));
    return next;
}
 

/**
 * Atomically updates the element at index {@code i} with the
 * results of applying the given function to the current and
 * given values, returning the previous value. The function should
 * be side-effect-free, since it may be re-applied when attempted
 * updates fail due to contention among threads.  The function is
 * applied with the current value at index {@code i} as its first
 * argument, and the given update as the second argument.
 *
 * @param i the index
 * @param x the update value
 * @param accumulatorFunction a side-effect-free function of two arguments
 * @return the previous value
 * @since 1.8
 */
public final int getAndAccumulate(int i, int x,
                                  IntBinaryOperator accumulatorFunction) {
    long offset = checkedByteOffset(i);
    int prev, next;
    do {
        prev = getRaw(offset);
        next = accumulatorFunction.applyAsInt(prev, x);
    } while (!compareAndSetRaw(offset, prev, next));
    return prev;
}
 

/**
 * Atomically updates the field of the given object managed by this
 * updater with the results of applying the given function to the
 * current and given values, returning the updated value. The
 * function should be side-effect-free, since it may be re-applied
 * when attempted updates fail due to contention among threads.  The
 * function is applied with the current value as its first argument,
 * and the given update as the second argument.
 *
 * @param obj An object whose field to get and set
 * @param x the update value
 * @param accumulatorFunction a side-effect-free function of two arguments
 * @return the updated value
 * @since 1.8
 */
public final int accumulateAndGet(T obj, int x,
                                  IntBinaryOperator accumulatorFunction) {
    int prev, next;
    do {
        prev = get(obj);
        next = accumulatorFunction.applyAsInt(prev, x);
    } while (!compareAndSet(obj, prev, next));
    return next;
}
 

/**
 * Atomically updates the field of the given object managed by this
 * updater with the results of applying the given function to the
 * current and given values, returning the updated value. The
 * function should be side-effect-free, since it may be re-applied
 * when attempted updates fail due to contention among threads.  The
 * function is applied with the current value as its first argument,
 * and the given update as the second argument.
 *
 * @param obj An object whose field to get and set
 * @param x the update value
 * @param accumulatorFunction a side-effect-free function of two arguments
 * @return the updated value
 * @since 1.8
 */
public final int accumulateAndGet(T obj, int x,
                                  IntBinaryOperator accumulatorFunction) {
    int prev, next;
    do {
        prev = get(obj);
        next = accumulatorFunction.applyAsInt(prev, x);
    } while (!compareAndSet(obj, prev, next));
    return next;
}
 

/**
 * Atomically updates the element at index {@code i} with the
 * results of applying the given function to the current and
 * given values, returning the updated value. The function should
 * be side-effect-free, since it may be re-applied when attempted
 * updates fail due to contention among threads.  The function is
 * applied with the current value at index {@code i} as its first
 * argument, and the given update as the second argument.
 *
 * @param i the index
 * @param x the update value
 * @param accumulatorFunction a side-effect-free function of two arguments
 * @return the updated value
 * @since 1.8
 */
public final int accumulateAndGet(int i, int x,
                                  IntBinaryOperator accumulatorFunction) {
    long offset = checkedByteOffset(i);
    int prev, next;
    do {
        prev = getRaw(offset);
        next = accumulatorFunction.applyAsInt(prev, x);
    } while (!compareAndSetRaw(offset, prev, next));
    return next;
}
 

/**
 * Atomically updates the field of the given object managed by this
 * updater with the results of applying the given function to the
 * current and given values, returning the previous value. The
 * function should be side-effect-free, since it may be re-applied
 * when attempted updates fail due to contention among threads.  The
 * function is applied with the current value as its first argument,
 * and the given update as the second argument.
 *
 * @param obj An object whose field to get and set
 * @param x the update value
 * @param accumulatorFunction a side-effect-free function of two arguments
 * @return the previous value
 * @since 1.8
 */
public final int getAndAccumulate(T obj, int x,
                                  IntBinaryOperator accumulatorFunction) {
    int prev, next;
    do {
        prev = get(obj);
        next = accumulatorFunction.applyAsInt(prev, x);
    } while (!compareAndSet(obj, prev, next));
    return prev;
}
 

/**
 * Atomically updates the current value with the results of
 * applying the given function to the current and given values,
 * returning the updated value. The function should be
 * side-effect-free, since it may be re-applied when attempted
 * updates fail due to contention among threads.  The function
 * is applied with the current value as its first argument,
 * and the given update as the second argument.
 *
 * @param x the update value
 * @param accumulatorFunction a side-effect-free function of two arguments
 * @return the updated value
 * @since 1.8
 */
public final int accumulateAndGet(int x,
                                  IntBinaryOperator accumulatorFunction) {
    int prev, next;
    do {
        prev = get();
        next = accumulatorFunction.applyAsInt(prev, x);
    } while (!compareAndSet(prev, next));
    return next;
}
 

/**
 * Atomically updates the current value with the results of
 * applying the given function to the current and given values,
 * returning the previous value. The function should be
 * side-effect-free, since it may be re-applied when attempted
 * updates fail due to contention among threads.  The function
 * is applied with the current value as its first argument,
 * and the given update as the second argument.
 *
 * @param x the update value
 * @param accumulatorFunction a side-effect-free function of two arguments
 * @return the previous value
 * @since 1.8
 */
// For desugar: made static so it can exist outside original class
public static int getAndAccumulate(AtomicInteger atomic, int x,
                                   IntBinaryOperator accumulatorFunction) {
    int prev, next;
    do {
        prev = atomic.get();
        next = accumulatorFunction.applyAsInt(prev, x);
    } while (!atomic.compareAndSet(prev, next));
    return prev;
}
 

/**
 * Atomically updates the field of the given object managed by this
 * updater with the results of applying the given function to the
 * current and given values, returning the updated value. The
 * function should be side-effect-free, since it may be re-applied
 * when attempted updates fail due to contention among threads.  The
 * function is applied with the current value as its first argument,
 * and the given update as the second argument.
 *
 * @param obj An object whose field to get and set
 * @param x the update value
 * @param accumulatorFunction a side-effect-free function of two arguments
 * @return the updated value
 * @since 1.8
 */
public final int accumulateAndGet(T obj, int x,
                                  IntBinaryOperator accumulatorFunction) {
    int prev, next;
    do {
        prev = get(obj);
        next = accumulatorFunction.applyAsInt(prev, x);
    } while (!compareAndSet(obj, prev, next));
    return next;
}
 

/**
 * Atomically updates the current value with the results of
 * applying the given function to the current and given values,
 * returning the previous value. The function should be
 * side-effect-free, since it may be re-applied when attempted
 * updates fail due to contention among threads.  The function
 * is applied with the current value as its first argument,
 * and the given update as the second argument.
 *
 * @param x the update value
 * @param accumulatorFunction a side-effect-free function of two arguments
 * @return the previous value
 * @since 1.8
 */
public final int getAndAccumulate(int x,
                                  IntBinaryOperator accumulatorFunction) {
    int prev, next;
    do {
        prev = get();
        next = accumulatorFunction.applyAsInt(prev, x);
    } while (!compareAndSet(prev, next));
    return prev;
}
 

/**
 * Atomically updates the element at index {@code i} with the
 * results of applying the given function to the current and
 * given values, returning the previous value. The function should
 * be side-effect-free, since it may be re-applied when attempted
 * updates fail due to contention among threads.  The function is
 * applied with the current value at index {@code i} as its first
 * argument, and the given update as the second argument.
 *
 * @param i the index
 * @param x the update value
 * @param accumulatorFunction a side-effect-free function of two arguments
 * @return the previous value
 * @since 1.8
 */
public final int getAndAccumulate(int i, int x,
                                  IntBinaryOperator accumulatorFunction) {
    long offset = checkedByteOffset(i);
    int prev, next;
    do {
        prev = getRaw(offset);
        next = accumulatorFunction.applyAsInt(prev, x);
    } while (!compareAndSetRaw(offset, prev, next));
    return prev;
}
 

/**
 * Atomically updates the current value with the results of
 * applying the given function to the current and given values,
 * returning the previous value. The function should be
 * side-effect-free, since it may be re-applied when attempted
 * updates fail due to contention among threads.  The function
 * is applied with the current value as its first argument,
 * and the given update as the second argument.
 *
 * @param x the update value
 * @param accumulatorFunction a side-effect-free function of two arguments
 * @return the previous value
 * @since 1.8
 */
public final int getAndAccumulate(int x,
                                  IntBinaryOperator accumulatorFunction) {
    int prev, next;
    do {
        prev = get();
        next = accumulatorFunction.applyAsInt(prev, x);
    } while (!compareAndSet(prev, next));
    return prev;
}