#5173

Committed 29 Dec 2025 05:27AM UTC coverage: 0.0% (-100.0%) from 100.0%

Build # #5173

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push

github

Committed by

ben-manes

Commit Message

speed up development ci build

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/caffeine/src/main/java/com/github/benmanes/caffeine/cache/Buffer.java

/*
 * Copyright 2015 Ben Manes. All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.github.benmanes.caffeine.cache;

import java.util.function.Consumer;

/**
 * A multiple-producer / single-consumer buffer that rejects new elements if it is full or
 * fails spuriously due to contention. Unlike a queue and stack, a buffer does not guarantee an
 * ordering of elements in either FIFO or LIFO order.
 * <p>
 * Beware that it is the responsibility of the caller to ensure that a consumer has exclusive read
 * access to the buffer. This implementation does <em>not</em> include fail-fast behavior to guard
 * against incorrect consumer usage.
 *
 * @param <E> the type of elements maintained by this buffer
 * @author ben.manes@gmail.com (Ben Manes)
 */
interface Buffer<E> {
  int FULL = 1;     // if the buffer is full
  int FAILED = -1;  // if the CAS failed
  int SUCCESS = 0;  // if added

  /** Returns a no-op implementation. */
  @SuppressWarnings("unchecked")
  static <E> Buffer<E> disabled() {
    return (Buffer<E>) DisabledBuffer.INSTANCE;
  }

  /**
   * Inserts the specified element into this buffer if it is possible to do so immediately without
   * violating capacity restrictions. The addition is allowed to fail spuriously if multiple
   * threads insert concurrently.
   *
   * @param e the element to add
   * @return {@code Buffer.SUCCESS}, {@code Buffer.FAILED}, or {@code Buffer.FULL}
   */
  int offer(E e);

  /**
   * Drains the buffer, sending each element to the consumer for processing. The caller must ensure
   * that a consumer has exclusive read access to the buffer.
   *
   * @param consumer the action to perform on each element
   */
  void drainTo(Consumer<E> consumer);

  /**
   * Returns the number of elements residing in the buffer.
   *
   * @return the number of elements in this buffer
   */
  default long size() {
    return writes() - reads();
  }

  /**
   * Returns the number of elements that have been read from the buffer.
   *
   * @return the number of elements read from this buffer
   */
  long reads();

  /**
   * Returns the number of elements that have been written to the buffer.
   *
   * @return the number of elements written to this buffer
   */
  long writes();
}

enum DisabledBuffer implements Buffer<Object> {
  INSTANCE;

  @Override public int offer(Object e) { return Buffer.SUCCESS; }
  @Override public void drainTo(Consumer<Object> consumer) {}
  @Override public long size() { return 0; }
  @Override public long reads() { return 0; }
  @Override public long writes() { return 0; }
}

1	/*
2	* Copyright 2015 Ben Manes. All Rights Reserved.
3	*
4	* Licensed under the Apache License, Version 2.0 (the "License");
5	* you may not use this file except in compliance with the License.
6	* You may obtain a copy of the License at
7	*
8	* http://www.apache.org/licenses/LICENSE-2.0
9	*
10	* Unless required by applicable law or agreed to in writing, software
11	* distributed under the License is distributed on an "AS IS" BASIS,
12	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13	* See the License for the specific language governing permissions and
14	* limitations under the License.
15	*/
16	package com.github.benmanes.caffeine.cache;
17
18	import java.util.function.Consumer;
19
20	/**
21	* A multiple-producer / single-consumer buffer that rejects new elements if it is full or
22	* fails spuriously due to contention. Unlike a queue and stack, a buffer does not guarantee an
23	* ordering of elements in either FIFO or LIFO order.
24	* <p>
25	* Beware that it is the responsibility of the caller to ensure that a consumer has exclusive read
26	* access to the buffer. This implementation does <em>not</em> include fail-fast behavior to guard
27	* against incorrect consumer usage.
28	*
29	* @param <E> the type of elements maintained by this buffer
30	* @author ben.manes@gmail.com (Ben Manes)
31	*/
32	interface Buffer<E> {
33	int FULL = 1; // if the buffer is full
34	int FAILED = -1; // if the CAS failed
35	int SUCCESS = 0; // if added
36
37	/** Returns a no-op implementation. */
38	@SuppressWarnings("unchecked")
39	static <E> Buffer<E> disabled() {
40	return (Buffer<E>) DisabledBuffer.INSTANCE;	×
41	}
42
43	/**
44	* Inserts the specified element into this buffer if it is possible to do so immediately without
45	* violating capacity restrictions. The addition is allowed to fail spuriously if multiple
46	* threads insert concurrently.
47	*
48	* @param e the element to add
49	* @return {@code Buffer.SUCCESS}, {@code Buffer.FAILED}, or {@code Buffer.FULL}
50	*/
51	int offer(E e);
52
53	/**
54	* Drains the buffer, sending each element to the consumer for processing. The caller must ensure
55	* that a consumer has exclusive read access to the buffer.
56	*
57	* @param consumer the action to perform on each element
58	*/
59	void drainTo(Consumer<E> consumer);
60
61	/**
62	* Returns the number of elements residing in the buffer.
63	*
64	* @return the number of elements in this buffer
65	*/
66	default long size() {
67	return writes() - reads();	×
68	}
69
70	/**
71	* Returns the number of elements that have been read from the buffer.
72	*
73	* @return the number of elements read from this buffer
74	*/
75	long reads();
76
77	/**
78	* Returns the number of elements that have been written to the buffer.
79	*
80	* @return the number of elements written to this buffer
81	*/
82	long writes();
83	}
84
85	enum DisabledBuffer implements Buffer<Object> {	×
86	INSTANCE;	×
87
88	@Override public int offer(Object e) { return Buffer.SUCCESS; }	×
89	@Override public void drainTo(Consumer<Object> consumer) {}	×
90	@Override public long size() { return 0; }	×
91	@Override public long reads() { return 0; }	×
92	@Override public long writes() { return 0; }	×
93	}

ben-manes / caffeine / #5173

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