init Distributed Queue

.gitignore

+target/
+!.mvn/wrapper/maven-wrapper.jar
+!**/src/main/**/target/
+!**/src/test/**/target/
+
+### IntelliJ IDEA ###
+.idea/modules.xml
+.idea/jarRepositories.xml
+.idea/compiler.xml
+.idea/libraries/
+*.iws
+*.iml
+*.ipr
+
+### Eclipse ###
+.apt_generated
+.classpath
+.factorypath
+.project
+.settings
+.springBeans
+.sts4-cache
+
+### NetBeans ###
+/nbproject/private/
+/nbbuild/
+/dist/
+/nbdist/
+/.nb-gradle/
+build/
+!**/src/main/**/build/
+!**/src/test/**/build/
+
+### VS Code ###
+.vscode/
+
+### Mac OS ###
+.DS_Store
\ No newline at end of file

.idea/artifacts/Consumer.xml

+<component name="ArtifactManager">
+  <artifact type="jar" name="Consumer">
+    <output-path>$PROJECT_DIR$/out/artifacts/Consumer</output-path>
+    <root id="archive" name="DQueue.jar">
+      <element id="module-output" name="DQueue" />
+      <element id="extracted-dir" path="$MAVEN_REPOSITORY$/io/netty/netty-common/4.1.94.Final/netty-common-4.1.94.Final.jar" path-in-jar="/" />
+      <element id="extracted-dir" path="$MAVEN_REPOSITORY$/commons-io/commons-io/2.11.0/commons-io-2.11.0.jar" path-in-jar="/" />
+      <element id="extracted-dir" path="$MAVEN_REPOSITORY$/io/netty/netty-transport-native-unix-common/4.1.94.Final/netty-transport-native-unix-common-4.1.94.Final.jar" path-in-jar="/" />
+      <element id="extracted-dir" path="$MAVEN_REPOSITORY$/ch/qos/logback/logback-core/1.2.10/logback-core-1.2.10.jar" path-in-jar="/" />
+      <element id="extracted-dir" path="$MAVEN_REPOSITORY$/io/netty/netty-tcnative-boringssl-static/2.0.61.Final/netty-tcnative-boringssl-static-2.0.61.Final-osx-aarch_64.jar" path-in-jar="/" />
+      <element id="extracted-dir" path="$MAVEN_REPOSITORY$/io/netty/netty-tcnative-boringssl-static/2.0.61.Final/netty-tcnative-boringssl-static-2.0.61.Final-windows-x86_64.jar" path-in-jar="/" />
+      <element id="extracted-dir" path="$MAVEN_REPOSITORY$/io/netty/netty-tcnative-boringssl-static/2.0.61.Final/netty-tcnative-boringssl-static-2.0.61.Final-linux-aarch_64.jar" path-in-jar="/" />
+      <element id="extracted-dir" path="$MAVEN_REPOSITORY$/io/netty/netty-tcnative-boringssl-static/2.0.61.Final/netty-tcnative-boringssl-static-2.0.61.Final.jar" path-in-jar="/" />
+      <element id="extracted-dir" path="$MAVEN_REPOSITORY$/io/netty/netty-transport-classes-epoll/4.1.94.Final/netty-transport-classes-epoll-4.1.94.Final.jar" path-in-jar="/" />
+      <element id="extracted-dir" path="$MAVEN_REPOSITORY$/io/netty/netty-tcnative-boringssl-static/2.0.61.Final/netty-tcnative-boringssl-static-2.0.61.Final-osx-x86_64.jar" path-in-jar="/" />
+      <element id="extracted-dir" path="$MAVEN_REPOSITORY$/io/netty/netty-buffer/4.1.94.Final/netty-buffer-4.1.94.Final.jar" path-in-jar="/" />
+      <element id="extracted-dir" path="$MAVEN_REPOSITORY$/io/netty/netty-resolver/4.1.94.Final/netty-resolver-4.1.94.Final.jar" path-in-jar="/" />
+      <element id="extracted-dir" path="$MAVEN_REPOSITORY$/org/apache/zookeeper/zookeeper/3.9.1/zookeeper-3.9.1.jar" path-in-jar="/" />
+      <element id="extracted-dir" path="$MAVEN_REPOSITORY$/org/apache/yetus/audience-annotations/0.12.0/audience-annotations-0.12.0.jar" path-in-jar="/" />
+      <element id="extracted-dir" path="$MAVEN_REPOSITORY$/io/netty/netty-transport/4.1.94.Final/netty-transport-4.1.94.Final.jar" path-in-jar="/" />
+      <element id="extracted-dir" path="$MAVEN_REPOSITORY$/io/netty/netty-tcnative-classes/2.0.61.Final/netty-tcnative-classes-2.0.61.Final.jar" path-in-jar="/" />
+      <element id="extracted-dir" path="$MAVEN_REPOSITORY$/io/netty/netty-codec/4.1.94.Final/netty-codec-4.1.94.Final.jar" path-in-jar="/" />
+      <element id="extracted-dir" path="$MAVEN_REPOSITORY$/org/slf4j/slf4j-api/1.7.30/slf4j-api-1.7.30.jar" path-in-jar="/" />
+      <element id="extracted-dir" path="$MAVEN_REPOSITORY$/io/netty/netty-handler/4.1.94.Final/netty-handler-4.1.94.Final.jar" path-in-jar="/" />
+      <element id="extracted-dir" path="$MAVEN_REPOSITORY$/org/apache/zookeeper/zookeeper-jute/3.9.1/zookeeper-jute-3.9.1.jar" path-in-jar="/" />
+      <element id="extracted-dir" path="$MAVEN_REPOSITORY$/io/netty/netty-tcnative-boringssl-static/2.0.61.Final/netty-tcnative-boringssl-static-2.0.61.Final-linux-x86_64.jar" path-in-jar="/" />
+      <element id="extracted-dir" path="$MAVEN_REPOSITORY$/ch/qos/logback/logback-classic/1.2.10/logback-classic-1.2.10.jar" path-in-jar="/" />
+      <element id="extracted-dir" path="$MAVEN_REPOSITORY$/io/netty/netty-transport-native-epoll/4.1.94.Final/netty-transport-native-epoll-4.1.94.Final-linux-x86_64.jar" path-in-jar="/" />
+    </root>
+  </artifact>
+</component>
\ No newline at end of file

.idea/artifacts/Producer.xml

+<component name="ArtifactManager">
+  <artifact type="jar" name="Producer">
+    <output-path>$PROJECT_DIR$/out/artifacts/Producer</output-path>
+    <root id="archive" name="DQueue.jar">
+      <element id="module-output" name="DQueue" />
+      <element id="extracted-dir" path="$MAVEN_REPOSITORY$/io/netty/netty-common/4.1.94.Final/netty-common-4.1.94.Final.jar" path-in-jar="/" />
+      <element id="extracted-dir" path="$MAVEN_REPOSITORY$/commons-io/commons-io/2.11.0/commons-io-2.11.0.jar" path-in-jar="/" />
+      <element id="extracted-dir" path="$MAVEN_REPOSITORY$/io/netty/netty-transport-native-unix-common/4.1.94.Final/netty-transport-native-unix-common-4.1.94.Final.jar" path-in-jar="/" />
+      <element id="extracted-dir" path="$MAVEN_REPOSITORY$/ch/qos/logback/logback-core/1.2.10/logback-core-1.2.10.jar" path-in-jar="/" />
+      <element id="extracted-dir" path="$MAVEN_REPOSITORY$/io/netty/netty-tcnative-boringssl-static/2.0.61.Final/netty-tcnative-boringssl-static-2.0.61.Final-osx-aarch_64.jar" path-in-jar="/" />
+      <element id="extracted-dir" path="$MAVEN_REPOSITORY$/io/netty/netty-tcnative-boringssl-static/2.0.61.Final/netty-tcnative-boringssl-static-2.0.61.Final-windows-x86_64.jar" path-in-jar="/" />
+      <element id="extracted-dir" path="$MAVEN_REPOSITORY$/io/netty/netty-tcnative-boringssl-static/2.0.61.Final/netty-tcnative-boringssl-static-2.0.61.Final-linux-aarch_64.jar" path-in-jar="/" />
+      <element id="extracted-dir" path="$MAVEN_REPOSITORY$/io/netty/netty-tcnative-boringssl-static/2.0.61.Final/netty-tcnative-boringssl-static-2.0.61.Final.jar" path-in-jar="/" />
+      <element id="extracted-dir" path="$MAVEN_REPOSITORY$/io/netty/netty-transport-classes-epoll/4.1.94.Final/netty-transport-classes-epoll-4.1.94.Final.jar" path-in-jar="/" />
+      <element id="extracted-dir" path="$MAVEN_REPOSITORY$/io/netty/netty-tcnative-boringssl-static/2.0.61.Final/netty-tcnative-boringssl-static-2.0.61.Final-osx-x86_64.jar" path-in-jar="/" />
+      <element id="extracted-dir" path="$MAVEN_REPOSITORY$/io/netty/netty-buffer/4.1.94.Final/netty-buffer-4.1.94.Final.jar" path-in-jar="/" />
+      <element id="extracted-dir" path="$MAVEN_REPOSITORY$/io/netty/netty-resolver/4.1.94.Final/netty-resolver-4.1.94.Final.jar" path-in-jar="/" />
+      <element id="extracted-dir" path="$MAVEN_REPOSITORY$/org/apache/zookeeper/zookeeper/3.9.1/zookeeper-3.9.1.jar" path-in-jar="/" />
+      <element id="extracted-dir" path="$MAVEN_REPOSITORY$/org/apache/yetus/audience-annotations/0.12.0/audience-annotations-0.12.0.jar" path-in-jar="/" />
+      <element id="extracted-dir" path="$MAVEN_REPOSITORY$/io/netty/netty-transport/4.1.94.Final/netty-transport-4.1.94.Final.jar" path-in-jar="/" />
+      <element id="extracted-dir" path="$MAVEN_REPOSITORY$/io/netty/netty-tcnative-classes/2.0.61.Final/netty-tcnative-classes-2.0.61.Final.jar" path-in-jar="/" />
+      <element id="extracted-dir" path="$MAVEN_REPOSITORY$/io/netty/netty-codec/4.1.94.Final/netty-codec-4.1.94.Final.jar" path-in-jar="/" />
+      <element id="extracted-dir" path="$MAVEN_REPOSITORY$/org/slf4j/slf4j-api/1.7.30/slf4j-api-1.7.30.jar" path-in-jar="/" />
+      <element id="extracted-dir" path="$MAVEN_REPOSITORY$/io/netty/netty-handler/4.1.94.Final/netty-handler-4.1.94.Final.jar" path-in-jar="/" />
+      <element id="extracted-dir" path="$MAVEN_REPOSITORY$/org/apache/zookeeper/zookeeper-jute/3.9.1/zookeeper-jute-3.9.1.jar" path-in-jar="/" />
+      <element id="extracted-dir" path="$MAVEN_REPOSITORY$/io/netty/netty-tcnative-boringssl-static/2.0.61.Final/netty-tcnative-boringssl-static-2.0.61.Final-linux-x86_64.jar" path-in-jar="/" />
+      <element id="extracted-dir" path="$MAVEN_REPOSITORY$/ch/qos/logback/logback-classic/1.2.10/logback-classic-1.2.10.jar" path-in-jar="/" />
+      <element id="extracted-dir" path="$MAVEN_REPOSITORY$/io/netty/netty-transport-native-epoll/4.1.94.Final/netty-transport-native-epoll-4.1.94.Final-linux-x86_64.jar" path-in-jar="/" />
+    </root>
+  </artifact>
+</component>
\ No newline at end of file

.idea/easycode.ignore

+node_modules/
+dist/
+vendor/
+cache/
+.*/
+*.min.*
+*.test.*
+*.spec.*
+*.bundle.*
+*.bundle-min.*
+*.*.js
+*.*.ts
+*.log

.idea/encodings.xml

+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="Encoding">
+    <file url="file://$PROJECT_DIR$/src/main/java" charset="UTF-8" />
+    <file url="file://$PROJECT_DIR$/src/main/resources" charset="UTF-8" />
+  </component>
+</project>
\ No newline at end of file

.idea/misc.xml

+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="ExternalStorageConfigurationManager" enabled="true" />
+  <component name="MavenProjectsManager">
+    <option name="originalFiles">
+      <list>
+        <option value="$PROJECT_DIR$/pom.xml" />
+      </list>
+    </option>
+  </component>
+  <component name="ProjectRootManager" version="2" languageLevel="JDK_17" default="true" project-jdk-name="17" project-jdk-type="JavaSDK">
+    <output url="file://$PROJECT_DIR$/out" />
+  </component>
+</project>
\ No newline at end of file

.idea/vcs.xml

+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="VcsDirectoryMappings">
+    <mapping directory="$PROJECT_DIR$" vcs="Git" />
+  </component>
+</project>
\ No newline at end of file

.idea/workspace.xml

+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="ArtifactsWorkspaceSettings">
+    <artifacts-to-build>
+      <artifact name="Consumer" />
+      <artifact name="Producer" />
+    </artifacts-to-build>
+  </component>
+  <component name="AutoImportSettings">
+    <option name="autoReloadType" value="SELECTIVE" />
+  </component>
+  <component name="ChangeListManager">
+    <list default="true" id="1cd303de-8197-4240-98f1-ed0399d5054e" name="Changes" comment="">
+      <change afterPath="$PROJECT_DIR$/.gitignore" afterDir="false" />
+      <change afterPath="$PROJECT_DIR$/.idea/artifacts/Consumer.xml" afterDir="false" />
+      <change afterPath="$PROJECT_DIR$/.idea/artifacts/Producer.xml" afterDir="false" />
+      <change afterPath="$PROJECT_DIR$/.idea/easycode.ignore" afterDir="false" />
+      <change afterPath="$PROJECT_DIR$/.idea/easycode/codebase-v2.xml" afterDir="false" />
+      <change afterPath="$PROJECT_DIR$/.idea/encodings.xml" afterDir="false" />
+      <change afterPath="$PROJECT_DIR$/.idea/misc.xml" afterDir="false" />
+      <change afterPath="$PROJECT_DIR$/.idea/vcs.xml" afterDir="false" />
+      <change afterPath="$PROJECT_DIR$/.idea/workspace.xml" afterDir="false" />
+      <change afterPath="$PROJECT_DIR$/pom.xml" afterDir="false" />
+      <change afterPath="$PROJECT_DIR$/src/main/java/org/ds/LockQueue.java" afterDir="false" />
+      <change afterPath="$PROJECT_DIR$/src/main/java/org/ds/NoLockQueue.java" afterDir="false" />
+      <change afterPath="$PROJECT_DIR$/src/main/java/org/ds/interfaces/Queue.java" afterDir="false" />
+      <change afterPath="$PROJECT_DIR$/src/main/java/org/ds/tester/Consumer.java" afterDir="false" />
+      <change afterPath="$PROJECT_DIR$/src/main/java/org/ds/tester/Producer.java" afterDir="false" />
+      <change afterPath="$PROJECT_DIR$/src/main/java/org/ds/utils/Constants.java" afterDir="false" />
+      <change afterPath="$PROJECT_DIR$/src/main/java/org/ds/utils/DistributedLock.java" afterDir="false" />
+      <change afterPath="$PROJECT_DIR$/src/main/java/org/ds/utils/Helper.java" afterDir="false" />
+      <change afterPath="$PROJECT_DIR$/src/main/java/org/ds/utils/LockType.java" afterDir="false" />
+      <change afterPath="$PROJECT_DIR$/src/main/java/org/ds/utils/QueueFactory.java" afterDir="false" />
+      <change afterPath="$PROJECT_DIR$/src/main/resources/logback.xml" afterDir="false" />
+    </list>
+    <option name="SHOW_DIALOG" value="false" />
+    <option name="HIGHLIGHT_CONFLICTS" value="true" />
+    <option name="HIGHLIGHT_NON_ACTIVE_CHANGELIST" value="false" />
+    <option name="LAST_RESOLUTION" value="IGNORE" />
+  </component>
+  <component name="Git.Settings">
+    <option name="RECENT_GIT_ROOT_PATH" value="$PROJECT_DIR$" />
+  </component>
+  <component name="ProjectColorInfo">{
+  &quot;associatedIndex&quot;: 7
+}</component>
+  <component name="ProjectId" id="2pT3WtKEjgINHUhCUNJ3g0o52pl" />
+  <component name="ProjectLevelVcsManager" settingsEditedManually="true" />
+  <component name="ProjectViewState">
+    <option name="hideEmptyMiddlePackages" value="true" />
+    <option name="showLibraryContents" value="true" />
+  </component>
+  <component name="PropertiesComponent"><![CDATA[{
+  "keyToString": {
+    "Application.C1.executor": "Run",
+    "Application.C2.executor": "Run",
+    "Application.Consumer.executor": "Run",
+    "Application.P1.executor": "Run",
+    "Application.P2.executor": "Run",
+    "Application.Producer.executor": "Run",
+    "RunOnceActivity.ShowReadmeOnStart": "true",
+    "SHARE_PROJECT_CONFIGURATION_FILES": "true",
+    "git-widget-placeholder": "master",
+    "kotlin-language-version-configured": "true",
+    "last_opened_file_path": "D:/HIAST Library/Teaching/DS/2025/Labs/Lab9/DQueue/DQueue/src/main/resources",
+    "project.structure.last.edited": "Artifacts",
+    "project.structure.proportion": "0.15",
+    "project.structure.side.proportion": "0.2850575",
+    "settings.editor.selected.configurable": "preferences.lookFeel"
+  }
+}]]></component>
+  <component name="RecentsManager">
+    <key name="CopyFile.RECENT_KEYS">
+      <recent name="D:\HIAST Library\Teaching\DS\2025\Labs\Lab9\DQueue\DQueue\src\main\resources" />
+      <recent name="D:\HIAST Library\Teaching\DS\2025\Labs\Lab9\DQueue\DQueue\src\main\java\org\ds" />
+    </key>
+  </component>
+  <component name="RunManager" selected="Application.C2">
+    <configuration name="C1" type="Application" factoryName="Application">
+      <option name="MAIN_CLASS_NAME" value="org.ds.tester.Consumer" />
+      <module name="DQueue" />
+      <method v="2">
+        <option name="Make" enabled="true" />
+      </method>
+    </configuration>
+    <configuration name="C2" type="Application" factoryName="Application">
+      <option name="MAIN_CLASS_NAME" value="org.ds.tester.Consumer" />
+      <module name="DQueue" />
+      <method v="2">
+        <option name="Make" enabled="true" />
+      </method>
+    </configuration>
+    <configuration name="Producer" type="Application" factoryName="Application">
+      <option name="MAIN_CLASS_NAME" value="org.ds.tester.Producer" />
+      <module name="DQueue" />
+      <method v="2">
+        <option name="Make" enabled="true" />
+      </method>
+    </configuration>
+    <list>
+      <item itemvalue="Application.Producer" />
+      <item itemvalue="Application.C1" />
+      <item itemvalue="Application.C2" />
+    </list>
+  </component>
+  <component name="SpellCheckerSettings" RuntimeDictionaries="0" Folders="0" CustomDictionaries="0" DefaultDictionary="application-level" UseSingleDictionary="true" transferred="true" />
+  <component name="TaskManager">
+    <task active="true" id="Default" summary="Default task">
+      <changelist id="1cd303de-8197-4240-98f1-ed0399d5054e" name="Changes" comment="" />
+      <created>1732776272916</created>
+      <option name="number" value="Default" />
+      <option name="presentableId" value="Default" />
+      <updated>1732776272916</updated>
+    </task>
+    <servers />
+  </component>
+</project>
\ No newline at end of file

pom.xml

+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+
+    <groupId>org.ds</groupId>
+    <artifactId>DQueue</artifactId>
+    <version>1.0-SNAPSHOT</version>
+
+    <properties>
+        <maven.compiler.source>17</maven.compiler.source>
+        <maven.compiler.target>17</maven.compiler.target>
+        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+    </properties>
+
+    <dependencies>
+        <dependency>
+            <groupId>org.apache.zookeeper</groupId>
+            <artifactId>zookeeper</artifactId>
+            <version>3.9.1</version>
+        </dependency>
+
+    </dependencies>
+</project>
\ No newline at end of file

src/main/java/org/ds/LockQueue.java

+package org.ds;
+
+import org.apache.zookeeper.*;
+import org.ds.interfaces.Queue;
+import org.ds.utils.DistributedLock;
+import org.ds.utils.Helper;
+
+import java.util.List;
+
+public class LockQueue implements Queue {
+    private ZooKeeper zk;
+    private String queuePath;
+
+    public LockQueue(ZooKeeper zk, String queuePath) throws InterruptedException, KeeperException {
+        this.zk = zk;
+        this.queuePath = queuePath;
+        Helper.createNodeIfDoesNotExists(zk, queuePath);
+    }
+
+    public void enqueue(String item) throws Exception {
+        // Create an item node under the queue node with the item data
+
+    }
+
+    public String dequeue() throws Exception {
+        return "";
+    }
+}

src/main/java/org/ds/NoLockQueue.java

+package org.ds;
+
+import org.apache.zookeeper.*;
+import org.ds.interfaces.Queue;
+import org.ds.utils.Helper;
+
+import java.util.List;
+
+public class NoLockQueue implements Queue {
+    private ZooKeeper zk;
+    private String queuePath;
+
+    public NoLockQueue(ZooKeeper zk, String queuePath) throws InterruptedException, KeeperException {
+        this.zk = zk;
+        this.queuePath = queuePath;
+        Helper.createNodeIfDoesNotExists(zk, queuePath);
+    }
+
+    public void enqueue(String item) throws Exception {
+        // Create an item node under the queue node with the item data
+
+    }
+
+    public String dequeue() throws Exception {
+        return "";
+    }
+}
+

src/main/java/org/ds/interfaces/Queue.java

+package org.ds.interfaces;
+
+public interface Queue {
+    public void enqueue(String item) throws Exception;
+    public String dequeue() throws Exception;
+}

src/main/java/org/ds/tester/Consumer.java

+package org.ds.tester;
+
+import org.apache.zookeeper.ZooKeeper;
+import org.ds.interfaces.Queue;
+import org.ds.utils.Constants;
+import org.ds.utils.Helper;
+import org.ds.utils.LockType;
+import org.ds.utils.QueueFactory;
+
+public class Consumer {
+    public static void main(String[] args) throws Exception
+    {
+        LockType lockType =  LockType.Lock;
+        if(args.length > 0){
+            String lock = args[0];
+            lockType = LockType.valueOf(lock);
+        }
+
+        // Connect to the ZooKeeper instance running on localhost:2181
+        ZooKeeper zk = new ZooKeeper(Constants.zookeeperUrl, 20000, null);
+
+        Helper.createNodeIfDoesNotExists(zk, Constants.queuePath);
+
+        if(lockType == LockType.Lock){
+            Helper.createNodeIfDoesNotExists(zk, Constants.lockRootNode);
+        }
+
+        QueueFactory queueFactory = new QueueFactory(zk, Constants.queuePath);
+
+        // Create a distributed queue
+        Queue queue = queueFactory.GetQueue(lockType);
+
+        while (true){
+            String dequeValue = queue.dequeue();
+            if(dequeValue != null){
+                System.out.println(dequeValue);
+            }
+        }
+    }
+}

src/main/java/org/ds/tester/Producer.java

+package org.ds.tester;
+
+import org.apache.zookeeper.ZooKeeper;
+import org.ds.NoLockQueue;
+import org.ds.interfaces.Queue;
+import org.ds.utils.Constants;
+
+public class Producer {
+    public static void main(String[] args) throws Exception {
+        // Connect to the ZooKeeper instance running on localhost:2181
+        ZooKeeper zk = new ZooKeeper(Constants.zookeeperUrl, 20000, null);
+
+        // Create a distributed queue and enqueue items
+        Queue queue = new NoLockQueue(zk, Constants.queuePath);
+        int i = 0;
+        while (i < Integer.MAX_VALUE){
+            System.out.println("going to produce item"+i);
+            queue.enqueue("item"+i);
+            Thread.sleep(1000);
+            i++;
+        }
+
+        // Close the ZooKeeper connection
+        zk.close();
+    }
+}

src/main/java/org/ds/utils/Constants.java

+package org.ds.utils;
+
+public class Constants {
+    // The root node of the lock hierarchy
+    public static String lockRootNode = "/lock";
+
+    // Define the queue path and create necessary nodes
+    public static String queuePath = "/queue";
+
+    // Defines the zookeeper endpoint
+    public static String zookeeperUrl = "172.29.3.101:2181";
+
+}

src/main/java/org/ds/utils/DistributedLock.java

+package org.ds.utils;
+
+import org.apache.zookeeper.CreateMode;
+import org.apache.zookeeper.KeeperException;
+import org.apache.zookeeper.ZooDefs;
+import org.apache.zookeeper.ZooKeeper;
+
+import java.util.List;
+
+public class DistributedLock {
+    // The ZooKeeper client instance
+    private final ZooKeeper zk;
+    // The path of the node where the lock is created
+    private final String nodePath;
+    // The name of the lock node
+    private String lockNode;
+
+    public DistributedLock(ZooKeeper zk, String path) throws InterruptedException, KeeperException {
+        this.zk = zk;
+        this.nodePath = Constants.lockRootNode + path;
+        Helper.createNodeIfDoesNotExists(zk, Constants.lockRootNode);
+        Helper.createNodeIfDoesNotExists(zk, this.nodePath);
+    }
+
+    public boolean lock() throws InterruptedException, KeeperException {
+        // Create an ephemeral sequential znode under the lock znode
+        lockNode = zk.create(nodePath + "/lock-", new byte[0], ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.EPHEMERAL_SEQUENTIAL);
+
+
+        // Get the list of all znodes under the lock znode
+        List<String> children = zk.getChildren(nodePath, false);
+
+        // Sort the list of znodes in ascending order
+        children.sort(String::compareTo);
+
+        // Get the index of the lock node in the list
+        int index = children.indexOf(lockNode.substring(lockNode.lastIndexOf('/') + 1));
+
+        // If the lock node is the first one in the list, then we have acquired the lock
+        if(index == 0){
+            return true;
+        }else{
+            zk.delete(lockNode, -1 );
+            return false;
+        }
+    }
+
+    public void unlock() throws InterruptedException, KeeperException {
+        zk.delete(lockNode, -1);
+    }
+}

src/main/java/org/ds/utils/Helper.java

+package org.ds.utils;
+
+import org.apache.zookeeper.CreateMode;
+import org.apache.zookeeper.ZooDefs;
+import org.apache.zookeeper.ZooKeeper;
+
+public class Helper {
+
+    /**
+     * Create a node in ZooKeeper if it doesn't exist.
+     *
+     * @param zooKeeper the ZooKeeper instance to use
+     * @param nodePath  the path of the node to create
+     */
+    public static void createNodeIfDoesNotExists(ZooKeeper zooKeeper, String nodePath) {
+        try {
+            if (zooKeeper.exists(nodePath, false) == null) {
+
+                zooKeeper.create(nodePath, new byte[0], ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);
+            }
+        } catch (Exception e) {
+        }
+    }
+}

src/main/java/org/ds/utils/LockType.java

+package org.ds.utils;
+
+public enum LockType {
+    NoLock,
+    Lock,
+}

src/main/java/org/ds/utils/QueueFactory.java

+package org.ds.utils;
+
+import org.apache.zookeeper.KeeperException;
+import org.apache.zookeeper.ZooKeeper;
+import org.ds.LockQueue;
+import org.ds.NoLockQueue;
+import org.ds.interfaces.Queue;
+
+public class QueueFactory {
+    private ZooKeeper zk;
+    private String queuePath;
+
+    public QueueFactory(ZooKeeper zk, String queuePath) {
+        this.zk = zk;
+        this.queuePath = queuePath;
+    }
+
+    public Queue GetQueue(LockType lockType) throws InterruptedException, KeeperException {
+        if(LockType.Lock == lockType){
+            return new LockQueue(this.zk, this.queuePath);
+        }
+        return new NoLockQueue(this.zk, this.queuePath);
+    }
+}

src/main/resources/logback.xml

+<configuration>
+
+    <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
+        <!-- encoders are assigned the type
+             ch.qos.logback.classic.encoder.PatternLayoutEncoder by default -->
+        <encoder>
+            <pattern>%d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} -%kvp- %msg%n</pattern>
+        </encoder>
+    </appender>
+
+    <root level="error">
+        <appender-ref ref="STDOUT" />
+    </root>
+</configuration>
\ No newline at end of file