diff options
Diffstat (limited to 'veslibrary/ves_javalibrary/evel_javalib2/src/evel_javalibrary/att/com/RingBuffer.java')
| -rw-r--r-- | veslibrary/ves_javalibrary/evel_javalib2/src/evel_javalibrary/att/com/RingBuffer.java | 276 |
1 files changed, 0 insertions, 276 deletions
diff --git a/veslibrary/ves_javalibrary/evel_javalib2/src/evel_javalibrary/att/com/RingBuffer.java b/veslibrary/ves_javalibrary/evel_javalib2/src/evel_javalibrary/att/com/RingBuffer.java deleted file mode 100644 index e7e9559..0000000 --- a/veslibrary/ves_javalibrary/evel_javalib2/src/evel_javalibrary/att/com/RingBuffer.java +++ /dev/null @@ -1,276 +0,0 @@ -package evel_javalibrary.att.com;
-/**************************************************************************//**
- * @file
- * RingBuffer class
- *
- * This file implements internal Ringbuffer for storing and
- * forwarding events to Collector.
- *
- * License
- * -------
- * Unless otherwise specified, all software contained herein is
- * 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.
- *****************************************************************************/
-
-import java.util.concurrent.Semaphore;
-/*
- * Ringbuffer to store and Forward http(s) POST requests
- */
-public class RingBuffer {
-
- // message count semaphore
- public static Semaphore countsem;
- // space semaphore
- public static Semaphore spacesem;
- // lock semaphore
- public static Semaphore lock;
-
- public EvelObject[] elements = null;
-
- public int capacity = 0;
- public int writePos = 0;
- public int available = 0;
-
- /*
- * Constructs Ringbuffer of specified capacity
- */
- public RingBuffer(int capacity) {
- this.capacity = capacity;
- this.elements = new EvelObject[capacity];
- countsem = new Semaphore(1);
- spacesem = new Semaphore(capacity);
- lock = new Semaphore(1);
- }
-
- //resets the positions
- public void reset() {
- this.writePos = 0;
- this.available = 0;
- }
-
- //returns available capacity
- public int remainingCapacity() {
- return this.capacity - this.available;
- }
-
-
-
- //Puts Java object into ringbuffer
- public boolean put(EvelObject element){
-
- boolean ret = false;
- //acquire locks
- try {
- spacesem.acquire();
- lock.acquire();
- } catch (InterruptedException e) {
- // TODO Auto-generated catch block
- e.printStackTrace();
- }
-
-
- //store object
- if(available < capacity){
- if(writePos >= capacity){
- writePos = 0;
- }
- elements[writePos] = element;
- writePos++;
- available++;
- ret = true;
- }
-
- //release Locks
- lock.release();
- countsem.release();
-
-
- return ret;
- }
-
- public int put(EvelObject[] newElements){
- return put(newElements, newElements.length);
- }
-
- public int put(EvelObject[] newElements, int length){
- //Acquire locks
- try {
- spacesem.acquire();
- lock.acquire();
- } catch (InterruptedException e) {
- // TODO Auto-generated catch block
- e.printStackTrace();
- }
-
- int readPos = 0;
- if(this.writePos > this.available){
- //space above writePos is all empty
-
- if(length <= this.capacity - this.writePos){
- //space above writePos is sufficient to insert batch
-
- for(; readPos < length; readPos++){
- this.elements[this.writePos++] = newElements[readPos];
- }
- this.available += readPos;
- //release
- lock.release();
- countsem.release();
- return length;
-
- } else {
- //both space above writePos and below writePos is necessary to use
- //to insert batch.
-
- int lastEmptyPos = writePos - available;
-
- for(; this.writePos < this.capacity; this.writePos++){
- this.elements[this.writePos] = newElements[readPos++];
- }
-
- //fill into bottom of array too.
- this.writePos = 0;
-
- int endPos = Math.min(length - readPos, capacity - available - readPos);
- for(;this.writePos < endPos; this.writePos++){
- this.elements[this.writePos] = newElements[readPos++];
- }
- this.available += readPos;
- //release
- lock.release();
- countsem.release();
- return readPos;
- }
- } else {
- int endPos = this.capacity - this.available + this.writePos;
-
- for(; this.writePos < endPos; this.writePos++){
- this.elements[this.writePos] = newElements[readPos++];
- }
- this.available += readPos;
- //release
- lock.release();
- countsem.release();
-
- return readPos;
- }
-
- }
-
- /*
- * Takes a stored object in Ringbuffer and releases the space
- */
-
- public EvelObject take() {
-
- EvelObject nextObj;
- //acquire lock
- try {
- countsem.acquire();
- lock.acquire();
- } catch (InterruptedException e) {
- // TODO Auto-generated catch block
- e.printStackTrace();
- }
-
- if(available == 0){
- nextObj = null;
- }
- else {
- int nextSlot = writePos - available;
- if(nextSlot < 0){
- nextSlot += capacity;
- }
- nextObj = elements[nextSlot];
- available--;
- }
- //releases object
- lock.release();
- spacesem.release();
-
- return nextObj;
- }
-
-
- public int take(EvelObject[] into){
- return take(into, into.length);
- }
-
-
- public int take(EvelObject[] into, int length){
- int intoPos = 0;
-
- //acquire lock
- try {
- countsem.acquire();
- lock.acquire();
- } catch (InterruptedException e) {
- // TODO Auto-generated catch block
- e.printStackTrace();
- }
-
- if(available <= writePos){
- int nextPos= writePos - available;
- int endPos = nextPos + Math.min(available, length);
-
- for(;nextPos < endPos; nextPos++){
- into[intoPos++] = this.elements[nextPos];
- }
- this.available -= intoPos;
-
- //release
- lock.release();
- countsem.release();
-
- return intoPos;
- } else {
- int nextPos = writePos - available + capacity;
-
- int leftInTop = capacity - nextPos;
- if(length <= leftInTop){
- //copy directly
- for(; intoPos < length; intoPos++){
- into[intoPos] = this.elements[nextPos++];
- }
- this.available -= length;
- //release
- lock.release();
- countsem.release();
- return length;
-
- } else {
- //copy top
- for(; nextPos < capacity; nextPos++){
- into[intoPos++] = this.elements[nextPos];
- }
-
- //copy bottom - from 0 to writePos
- nextPos = 0;
- int leftToCopy = length - intoPos;
- int endPos = Math.min(writePos, leftToCopy);
-
- for(;nextPos < endPos; nextPos++){
- into[intoPos++] = this.elements[nextPos];
- }
-
- this.available -= intoPos;
-
- //release
- lock.release();
- countsem.release();
-
- return intoPos;
- }
- }
- }
-
-}
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