74 lines
1.4 KiB
Java
74 lines
1.4 KiB
Java
package com.baeldung.circularbuffer;
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public class CircularBuffer<E> {
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private static final int DEFAULT_CAPACITY = 8;
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private final int capacity;
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private final E[] data;
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private volatile int writeSequence, readSequence;
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@SuppressWarnings("unchecked")
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public CircularBuffer(int capacity) {
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this.capacity = (capacity < 1) ? DEFAULT_CAPACITY : capacity;
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this.data = (E[]) new Object[this.capacity];
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this.readSequence = 0;
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this.writeSequence = -1;
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}
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public boolean offer(E element) {
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if (isNotFull()) {
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int nextWriteSeq = writeSequence + 1;
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data[nextWriteSeq % capacity] = element;
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writeSequence++;
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return true;
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}
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return false;
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}
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public E poll() {
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if (isNotEmpty()) {
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E nextValue = data[readSequence % capacity];
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readSequence++;
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return nextValue;
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}
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return null;
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}
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public int capacity() {
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return capacity;
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}
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public int size() {
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return (writeSequence - readSequence) + 1;
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}
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public boolean isEmpty() {
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return writeSequence < readSequence;
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}
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public boolean isFull() {
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return size() >= capacity;
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}
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private boolean isNotEmpty() {
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return !isEmpty();
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}
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private boolean isNotFull() {
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return !isFull();
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}
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}
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