/*
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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/*
 *
 *
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 *
 * Written by Doug Lea with assistance from members of JCP JSR-166
 * Expert Group and released to the public domain, as explained at
 * http://creativecommons.org/publicdomain/zero/1.0/
 */

package java.util.concurrent.atomic;

import java.lang.invoke.MethodHandles;
import java.lang.invoke.VarHandle;
import java.util.function.IntBinaryOperator;
import java.util.function.IntUnaryOperator;

/**
 * An {@code int} array in which elements may be updated atomically.
 * See the {@link VarHandle} specification for descriptions of the
 * properties of atomic accesses.
 * @since 1.5
 * @author Doug Lea
 */
public class AtomicIntegerArray implements java.io.Serializable {
 private static final long serialVersionUID = 2862133569453604235L;
 private static final VarHandle AA
 = MethodHandles.arrayElementVarHandle(int[].class);
 private final int[] array;

 /**
 * Creates a new AtomicIntegerArray of the given length, with all
 * elements initially zero.
 *
 * @param length the length of the array
 */
 public AtomicIntegerArray(int length) {
 array = new int[length];
 }

 /**
 * Creates a new AtomicIntegerArray with the same length as, and
 * all elements copied from, the given array.
 *
 * @param array the array to copy elements from
 * @throws NullPointerException if array is null
 */
 public AtomicIntegerArray(int[] array) {
 // Visibility guaranteed by final field guarantees
 this.array = array.clone();
 }

 /**
 * Returns the length of the array.
 *
 * @return the length of the array
 */
 public final int length() {
 return array.length;
 }

 /**
 * Returns the current value of the element at index {@code i},
 * with memory effects as specified by {@link VarHandle#getVolatile}.
 *
 * @param i the index
 * @return the current value
 */
 public final int get(int i) {
 return (int)AA.getVolatile(array, i);
 }

 /**
 * Sets the element at index {@code i} to {@code newValue},
 * with memory effects as specified by {@link VarHandle#setVolatile}.
 *
 * @param i the index
 * @param newValue the new value
 */
 public final void set(int i, int newValue) {
 AA.setVolatile(array, i, newValue);
 }

 /**
 * Sets the element at index {@code i} to {@code newValue},
 * with memory effects as specified by {@link VarHandle#setRelease}.
 *
 * @param i the index
 * @param newValue the new value
 * @since 1.6
 */
 public final void lazySet(int i, int newValue) {
 AA.setRelease(array, i, newValue);
 }

 /**
 * Atomically sets the element at index {@code i} to {@code
 * newValue} and returns the old value,
 * with memory effects as specified by {@link VarHandle#getAndSet}.
 *
 * @param i the index
 * @param newValue the new value
 * @return the previous value
 */
 public final int getAndSet(int i, int newValue) {
 return (int)AA.getAndSet(array, i, newValue);
 }

 /**
 * Atomically sets the element at index {@code i} to {@code
 * newValue} if the element's current value {@code == expectedValue},
 * with memory effects as specified by {@link VarHandle#compareAndSet}.
 *
 * @param i the index
 * @param expectedValue the expected value
 * @param newValue the new value
 * @return {@code true} if successful. False return indicates that
 * the actual value was not equal to the expected value.
 */
 public final boolean compareAndSet(int i, int expectedValue, int newValue) {
 return AA.compareAndSet(array, i, expectedValue, newValue);
 }

 /**
 * Possibly atomically sets the element at index {@code i} to
 * {@code newValue} if the element's current value {@code == expectedValue},
 * with memory effects as specified by {@link VarHandle#weakCompareAndSetPlain}.
 *
 * @deprecated This method has plain memory effects but the method
 * name implies volatile memory effects (see methods such as
 * {@link #compareAndExchange} and {@link #compareAndSet}). To avoid
 * confusion over plain or volatile memory effects it is recommended that
 * the method {@link #weakCompareAndSetPlain} be used instead.
 *
 * @param i the index
 * @param expectedValue the expected value
 * @param newValue the new value
 * @return {@code true} if successful
 * @see #weakCompareAndSetPlain
 */
 @Deprecated(since="9")
 public final boolean weakCompareAndSet(int i, int expectedValue, int newValue) {
 return AA.weakCompareAndSetPlain(array, i, expectedValue, newValue);
 }

 /**
 * Possibly atomically sets the element at index {@code i} to
 * {@code newValue} if the element's current value {@code == expectedValue},
 * with memory effects as specified by {@link VarHandle#weakCompareAndSetPlain}.
 *
 * @param i the index
 * @param expectedValue the expected value
 * @param newValue the new value
 * @return {@code true} if successful
 * @since 9
 */
 public final boolean weakCompareAndSetPlain(int i, int expectedValue, int newValue) {
 return AA.weakCompareAndSetPlain(array, i, expectedValue, newValue);
 }

 /**
 * Atomically increments the value of the element at index {@code i},
 * with memory effects as specified by {@link VarHandle#getAndAdd}.
 *
 * <p>Equivalent to {@code getAndAdd(i, 1)}.
 *
 * @param i the index
 * @return the previous value
 */
 public final int getAndIncrement(int i) {
 return (int)AA.getAndAdd(array, i, 1);
 }

 /**
 * Atomically decrements the value of the element at index {@code i},
 * with memory effects as specified by {@link VarHandle#getAndAdd}.
 *
 * <p>Equivalent to {@code getAndAdd(i, -1)}.
 *
 * @param i the index
 * @return the previous value
 */
 public final int getAndDecrement(int i) {
 return (int)AA.getAndAdd(array, i, -1);
 }

 /**
 * Atomically adds the given value to the element at index {@code i},
 * with memory effects as specified by {@link VarHandle#getAndAdd}.
 *
 * @param i the index
 * @param delta the value to add
 * @return the previous value
 */
 public final int getAndAdd(int i, int delta) {
 return (int)AA.getAndAdd(array, i, delta);
 }

 /**
 * Atomically increments the value of the element at index {@code i},
 * with memory effects as specified by {@link VarHandle#getAndAdd}.
 *
 * <p>Equivalent to {@code addAndGet(i, 1)}.
 *
 * @param i the index
 * @return the updated value
 */
 public final int incrementAndGet(int i) {
 return (int)AA.getAndAdd(array, i, 1) + 1;
 }

 /**
 * Atomically decrements the value of the element at index {@code i},
 * with memory effects as specified by {@link VarHandle#getAndAdd}.
 *
 * <p>Equivalent to {@code addAndGet(i, -1)}.
 *
 * @param i the index
 * @return the updated value
 */
 public final int decrementAndGet(int i) {
 return (int)AA.getAndAdd(array, i, -1) - 1;
 }

 /**
 * Atomically adds the given value to the element at index {@code i},
 * with memory effects as specified by {@link VarHandle#getAndAdd}.
 *
 * @param i the index
 * @param delta the value to add
 * @return the updated value
 */
 public final int addAndGet(int i, int delta) {
 return (int)AA.getAndAdd(array, i, delta) + delta;
 }

 /**
 * Atomically updates (with memory effects as specified by {@link
 * VarHandle#compareAndSet}) the element at index {@code i} with
 * the results of applying the given function, 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.
 *
 * @param i the index
 * @param updateFunction a side-effect-free function
 * @return the previous value
 * @since 1.8
 */
 public final int getAndUpdate(int i, IntUnaryOperator updateFunction) {
 int prev = get(i), next = 0;
 for (boolean haveNext = false;;) {
 if (!haveNext)
 next = updateFunction.applyAsInt(prev);
 if (weakCompareAndSetVolatile(i, prev, next))
 return prev;
 haveNext = (prev == (prev = get(i)));
 }
 }

 /**
 * Atomically updates (with memory effects as specified by {@link
 * VarHandle#compareAndSet}) the element at index {@code i} with
 * the results of applying the given function, 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.
 *
 * @param i the index
 * @param updateFunction a side-effect-free function
 * @return the updated value
 * @since 1.8
 */
 public final int updateAndGet(int i, IntUnaryOperator updateFunction) {
 int prev = get(i), next = 0;
 for (boolean haveNext = false;;) {
 if (!haveNext)
 next = updateFunction.applyAsInt(prev);
 if (weakCompareAndSetVolatile(i, prev, next))
 return next;
 haveNext = (prev == (prev = get(i)));
 }
 }

 /**
 * Atomically updates (with memory effects as specified by {@link
 * VarHandle#compareAndSet}) 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 of the element 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) {
 int prev = get(i), next = 0;
 for (boolean haveNext = false;;) {
 if (!haveNext)
 next = accumulatorFunction.applyAsInt(prev, x);
 if (weakCompareAndSetVolatile(i, prev, next))
 return prev;
 haveNext = (prev == (prev = get(i)));
 }
 }

 /**
 * Atomically updates (with memory effects as specified by {@link
 * VarHandle#compareAndSet}) 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 of the element 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) {
 int prev = get(i), next = 0;
 for (boolean haveNext = false;;) {
 if (!haveNext)
 next = accumulatorFunction.applyAsInt(prev, x);
 if (weakCompareAndSetVolatile(i, prev, next))
 return next;
 haveNext = (prev == (prev = get(i)));
 }
 }

 /**
 * Returns the String representation of the current values of array.
 * @return the String representation of the current values of array
 */
 public String toString() {
 int iMax = array.length - 1;
 if (iMax == -1)
 return "[]";

 StringBuilder b = new StringBuilder();
 b.append('[');
 for (int i = 0; ; i++) {
 b.append(get(i));
 if (i == iMax)
 return b.append(']').toString();
 b.append(',').append(' ');
 }
 }

 // jdk9

 /**
 * Returns the current value of the element at index {@code i},
 * with memory semantics of reading as if the variable was declared
 * non-{@code volatile}.
 *
 * @param i the index
 * @return the value
 * @since 9
 */
 public final int getPlain(int i) {
 return (int)AA.get(array, i);
 }

 /**
 * Sets the element at index {@code i} to {@code newValue},
 * with memory semantics of setting as if the variable was
 * declared non-{@code volatile} and non-{@code final}.
 *
 * @param i the index
 * @param newValue the new value
 * @since 9
 */
 public final void setPlain(int i, int newValue) {
 AA.set(array, i, newValue);
 }

 /**
 * Returns the current value of the element at index {@code i},
 * with memory effects as specified by {@link VarHandle#getOpaque}.
 *
 * @param i the index
 * @return the value
 * @since 9
 */
 public final int getOpaque(int i) {
 return (int)AA.getOpaque(array, i);
 }

 /**
 * Sets the element at index {@code i} to {@code newValue},
 * with memory effects as specified by {@link VarHandle#setOpaque}.
 *
 * @param i the index
 * @param newValue the new value
 * @since 9
 */
 public final void setOpaque(int i, int newValue) {
 AA.setOpaque(array, i, newValue);
 }

 /**
 * Returns the current value of the element at index {@code i},
 * with memory effects as specified by {@link VarHandle#getAcquire}.
 *
 * @param i the index
 * @return the value
 * @since 9
 */
 public final int getAcquire(int i) {
 return (int)AA.getAcquire(array, i);
 }

 /**
 * Sets the element at index {@code i} to {@code newValue},
 * with memory effects as specified by {@link VarHandle#setRelease}.
 *
 * @param i the index
 * @param newValue the new value
 * @since 9
 */
 public final void setRelease(int i, int newValue) {
 AA.setRelease(array, i, newValue);
 }

 /**
 * Atomically sets the element at index {@code i} to {@code newValue}
 * if the element's current value, referred to as the <em>witness
 * value</em>, {@code == expectedValue},
 * with memory effects as specified by
 * {@link VarHandle#compareAndExchange}.
 *
 * @param i the index
 * @param expectedValue the expected value
 * @param newValue the new value
 * @return the witness value, which will be the same as the
 * expected value if successful
 * @since 9
 */
 public final int compareAndExchange(int i, int expectedValue, int newValue) {
 return (int)AA.compareAndExchange(array, i, expectedValue, newValue);
 }

 /**
 * Atomically sets the element at index {@code i} to {@code newValue}
 * if the element's current value, referred to as the <em>witness
 * value</em>, {@code == expectedValue},
 * with memory effects as specified by
 * {@link VarHandle#compareAndExchangeAcquire}.
 *
 * @param i the index
 * @param expectedValue the expected value
 * @param newValue the new value
 * @return the witness value, which will be the same as the
 * expected value if successful
 * @since 9
 */
 public final int compareAndExchangeAcquire(int i, int expectedValue, int newValue) {
 return (int)AA.compareAndExchangeAcquire(array, i, expectedValue, newValue);
 }

 /**
 * Atomically sets the element at index {@code i} to {@code newValue}
 * if the element's current value, referred to as the <em>witness
 * value</em>, {@code == expectedValue},
 * with memory effects as specified by
 * {@link VarHandle#compareAndExchangeRelease}.
 *
 * @param i the index
 * @param expectedValue the expected value
 * @param newValue the new value
 * @return the witness value, which will be the same as the
 * expected value if successful
 * @since 9
 */
 public final int compareAndExchangeRelease(int i, int expectedValue, int newValue) {
 return (int)AA.compareAndExchangeRelease(array, i, expectedValue, newValue);
 }

 /**
 * Possibly atomically sets the element at index {@code i} to
 * {@code newValue} if the element's current value {@code == expectedValue},
 * with memory effects as specified by
 * {@link VarHandle#weakCompareAndSet}.
 *
 * @param i the index
 * @param expectedValue the expected value
 * @param newValue the new value
 * @return {@code true} if successful
 * @since 9
 */
 public final boolean weakCompareAndSetVolatile(int i, int expectedValue, int newValue) {
 return AA.weakCompareAndSet(array, i, expectedValue, newValue);
 }

 /**
 * Possibly atomically sets the element at index {@code i} to
 * {@code newValue} if the element's current value {@code == expectedValue},
 * with memory effects as specified by
 * {@link VarHandle#weakCompareAndSetAcquire}.
 *
 * @param i the index
 * @param expectedValue the expected value
 * @param newValue the new value
 * @return {@code true} if successful
 * @since 9
 */
 public final boolean weakCompareAndSetAcquire(int i, int expectedValue, int newValue) {
 return AA.weakCompareAndSetAcquire(array, i, expectedValue, newValue);
 }

 /**
 * Possibly atomically sets the element at index {@code i} to
 * {@code newValue} if the element's current value {@code == expectedValue},
 * with memory effects as specified by
 * {@link VarHandle#weakCompareAndSetRelease}.
 *
 * @param i the index
 * @param expectedValue the expected value
 * @param newValue the new value
 * @return {@code true} if successful
 * @since 9
 */
 public final boolean weakCompareAndSetRelease(int i, int expectedValue, int newValue) {
 return AA.weakCompareAndSetRelease(array, i, expectedValue, newValue);
 }


}