+++ /dev/null
-/*
- * ============LICENSE_START==========================================
- * org.onap.music
- * ===================================================================
- * Copyright (c) 2017 AT&T Intellectual Property
- * Modifications Copyright (C) 2018 IBM.
- * ===================================================================
- * 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.
- *
- * ============LICENSE_END=============================================
- * ====================================================================
- */
-
-package org.onap.music.lockingservice.zookeeper;
-
-import org.apache.zookeeper.CreateMode;
-import org.apache.zookeeper.KeeperException;
-import org.apache.zookeeper.ZooDefs;
-import org.apache.zookeeper.ZooKeeper;
-import org.apache.zookeeper.data.ACL;
-import org.apache.zookeeper.data.Stat;
-import org.onap.music.eelf.logging.EELFLoggerDelegate;
-import org.onap.music.eelf.logging.format.AppMessages;
-import org.onap.music.eelf.logging.format.ErrorSeverity;
-import org.onap.music.eelf.logging.format.ErrorTypes;
-import org.onap.music.lockingservice.zookeeper.ZooKeeperOperation;
-
-import java.util.List;
-import java.util.concurrent.atomic.AtomicBoolean;
-
-/**
- * A base class for protocol implementations which provides a number of higher level helper methods
- * for working with ZooKeeper along with retrying synchronous operations if the connection to
- * ZooKeeper closes such as {@link #retryOperation(ZooKeeperOperation)}
- *
- */
-class ProtocolSupport {
- private EELFLoggerDelegate logger = EELFLoggerDelegate.getLogger(ProtocolSupport.class);
-
- protected ZooKeeper zookeeper;
- private AtomicBoolean closed = new AtomicBoolean(false);
- private long retryDelay = 500L;
- private int retryCount = 10;
- private List<ACL> acl = ZooDefs.Ids.OPEN_ACL_UNSAFE;
-
- /**
- * Closes this strategy and releases any ZooKeeper resources; but keeps the ZooKeeper instance
- * open
- */
- public void close() {
- if (closed.compareAndSet(false, true)) {
- doClose();
- }
- }
-
- /**
- * return zookeeper client instance
- *
- * @return zookeeper client instance
- */
- public ZooKeeper getZookeeper() {
- return zookeeper;
- }
-
- /**
- * return the acl its using
- *
- * @return the acl.
- */
- public List<ACL> getAcl() {
- return acl;
- }
-
- /**
- * set the acl
- *
- * @param acl the acl to set to
- */
- public void setAcl(List<ACL> acl) {
- this.acl = acl;
- }
-
- /**
- * get the retry delay in milliseconds
- *
- * @return the retry delay
- */
- public long getRetryDelay() {
- return retryDelay;
- }
-
- /**
- * Sets the time waited between retry delays
- *
- * @param retryDelay the retry delay
- */
- public void setRetryDelay(long retryDelay) {
- this.retryDelay = retryDelay;
- }
-
- /**
- * Allow derived classes to perform some custom closing operations to release resources
- */
- protected void doClose() {
- throw new UnsupportedOperationException();
- }
-
-
- /**
- * Perform the given operation, retrying if the connection fails
- *
- * @return object. it needs to be cast to the callee's expected return type.
- * @param operation FILL IN
- * @throws KeeperException FILL IN
- * @throws InterruptedException FILL IN
- */
- protected Object retryOperation(ZooKeeperOperation operation)
- throws KeeperException, InterruptedException {
- KeeperException exception = null;
- for (int i = 0; i < retryCount; i++) {
- try {
- return operation.execute();
- } catch (KeeperException.SessionExpiredException e) {
- logger.error(EELFLoggerDelegate.errorLogger, e,AppMessages.SESSIONEXPIRED+" for: " + zookeeper + " so reconnecting due to: " + e, ErrorSeverity.ERROR, ErrorTypes.SESSIONEXPIRED);
- throw e;
- } catch (KeeperException.ConnectionLossException e) {
- if (exception == null) {
- exception = e;
- }
- logger.error(EELFLoggerDelegate.errorLogger, e,AppMessages.CONNCECTIVITYERROR, ErrorSeverity.ERROR, ErrorTypes.SESSIONEXPIRED);
- logger.error(EELFLoggerDelegate.errorLogger, e,"Attempt " + i + " failed with connection loss so attempting to reconnect: " + e);
-
- retryDelay(i);
- }
- }
- if(exception == null)
- {
- throw new NullPointerException();
- }
- else{
- throw exception;
- }
- }
-
- /**
- * Ensures that the given path exists with no data, the current ACL and no flags
- *
- * @param path the lock path
- */
- protected void ensurePathExists(String path) {
- ensureExists(path, null, acl, CreateMode.PERSISTENT);
- }
-
- /**
- * Ensures that the given path exists with the given data, ACL and flags
- *
- * @param path the lock path
- * @param data the data
- * @param acl list of ACLs applying to the path
- * @param flags create mode flags
- */
- protected void ensureExists(final String path, final byte[] data, final List<ACL> acl,
- final CreateMode flags) {
- try {
- retryOperation(new ZooKeeperOperation() {
- public boolean execute() throws KeeperException, InterruptedException {
- Stat stat = zookeeper.exists(path, false);
- if (stat != null) {
- return true;
- }
- zookeeper.create(path, data, acl, flags);
- return true;
- }
- });
- } catch (KeeperException e) {
- logger.error(EELFLoggerDelegate.errorLogger, e.getMessage(),AppMessages.KEEPERERROR, ErrorSeverity.ERROR, ErrorTypes.LOCKINGERROR);
- } catch (InterruptedException e) {
- logger.error(EELFLoggerDelegate.errorLogger, e.getMessage(),AppMessages.EXECUTIONINTERRUPTED, ErrorSeverity.ERROR, ErrorTypes.LOCKINGERROR);
- }
- }
-
- /**
- * Returns true if this protocol has been closed
- *
- * @return true if this protocol is closed
- */
- protected boolean isClosed() {
- return closed.get();
- }
-
- /**
- * Performs a retry delay if this is not the first attempt
- *
- * @param attemptCount the number of the attempts performed so far
- */
- protected void retryDelay(int attemptCount) {
- if (attemptCount > 0) {
- try {
- Thread.sleep(attemptCount * retryDelay);
- } catch (InterruptedException e) {
- logger.error(EELFLoggerDelegate.errorLogger, e,AppMessages.EXECUTIONINTERRUPTED, ErrorSeverity.ERROR, ErrorTypes.GENERALSERVICEERROR);
- logger.error(EELFLoggerDelegate.errorLogger, e,"Thread failed to sleep: " + e);
- Thread.currentThread().interrupt();
- }
- }
- }
-}
Code Review / music.git / blobdiff