Add Synchronization

.gitattributes

+#
+# https://help.github.com/articles/dealing-with-line-endings/
+#
+# These are explicitly windows files and should use crlf
+*.bat           text eol=crlf
+

.gitignore

+# Ignore Gradle project-specific cache directory
+.gradle
+
+# Ignore Gradle build output directory
+build

.vscode/settings.json

+{
+    "java.compile.nullAnalysis.mode": "automatic"
+}
\ No newline at end of file

app/build.gradle

+/*
+ * This file was generated by the Gradle 'init' task.
+ *
+ * This generated file contains a sample Java application project to get you started.
+ * For more details take a look at the 'Building Java & JVM projects' chapter in the Gradle
+ * User Manual available at https://docs.gradle.org/7.4.2/userguide/building_java_projects.html
+ */
+
+plugins {
+    // Apply the application plugin to add support for building a CLI application in Java.
+    id 'application'
+}
+
+repositories {
+    // Use Maven Central for resolving dependencies.
+    mavenCentral()
+}
+
+dependencies {
+    // Use JUnit Jupiter for testing.
+    testImplementation 'org.junit.jupiter:junit-jupiter:5.8.1'
+
+    // This dependency is used by the application.
+    implementation 'com.google.guava:guava:30.1.1-jre'
+}
+
+application {
+    // Define the main class for the application.
+    mainClass = 'com.crio.threads.App'
+}
+
+tasks.named('test') {
+    // Use JUnit Platform for unit tests.
+    useJUnitPlatform()
+}

app/src/main/java/com/crio/threads/App.java

+/*
+ * This Java source file was generated by the Gradle 'init' task.
+ */
+package com.crio.threads;
+
+public class App {
+    public String getGreeting() {
+        return "Hello World!";
+    }
+
+    public static void main(String[] args) {
+        System.out.println(new App().getGreeting());
+    }
+}

app/src/main/java/com/crio/threads/inventorycounter/App.java

+    package com.crio.threads.inventorycounter;
+
+    public class App {
+        public static void main(String[] args) throws InterruptedException {
+            InventoryCounter inventoryCounter = new InventoryCounter();
+            IncrementingThread incrementingThread = new IncrementingThread(inventoryCounter);
+            DecrementingThread decrementingThread = new DecrementingThread(inventoryCounter);
+
+            incrementingThread.start();
+            decrementingThread.start();
+
+            incrementingThread.join();
+            decrementingThread.join();
+
+            System.out.println("We currently have " + inventoryCounter.getItems() + " items");
+        }
+
+        public static class DecrementingThread extends Thread {
+
+            private InventoryCounter inventoryCounter;
+
+            public DecrementingThread(InventoryCounter inventoryCounter) {
+                this.inventoryCounter = inventoryCounter;
+            }
+
+            @Override
+            public void run() {
+                for (int i = 0; i < 10000; i++) {
+                    inventoryCounter.decrement();
+                }
+            }
+        }
+
+        public static class IncrementingThread extends Thread {
+
+            private InventoryCounter inventoryCounter;
+
+            public IncrementingThread(InventoryCounter inventoryCounter) {
+                this.inventoryCounter = inventoryCounter;
+            }
+
+            @Override
+            public void run() {
+                for (int i = 0; i < 10000; i++) {
+                    inventoryCounter.increment();
+                }
+            }
+        }
+
+        private static class InventoryCounter {
+            private int items = 0;
+
+            public void increment() {
+                // Enter critical section
+                items++; 
+                // Exit critical section
+            }
+
+            public void decrement() {
+                // Enter critical section
+                items--;
+                 // Exit critical section
+            }
+
+            public int getItems() {
+                // Enter critical section
+                return items;
+                // Exit critical section
+            }
+        }
+    }

app/src/main/java/com/crio/threads/inventorycountersynchronizedblocks/App.java

+    package com.crio.threads.inventorycountersynchronizedblocks;
+
+    public class App {
+        public static void main(String[] args) throws InterruptedException {
+            InventoryCounter inventoryCounter = new InventoryCounter();
+            IncrementingThread incrementingThread = new IncrementingThread(inventoryCounter);
+            DecrementingThread decrementingThread = new DecrementingThread(inventoryCounter);
+
+            incrementingThread.start();
+            decrementingThread.start();
+
+            incrementingThread.join();
+            decrementingThread.join();
+
+            System.out.println("We currently have " + inventoryCounter.getItems() + " items");
+        }
+
+        public static class DecrementingThread extends Thread {
+
+            private InventoryCounter inventoryCounter;
+
+            public DecrementingThread(InventoryCounter inventoryCounter) {
+                this.inventoryCounter = inventoryCounter;
+            }
+
+            @Override
+            public void run() {
+                for (int i = 0; i < 10000; i++) {
+                    inventoryCounter.decrement();
+                }
+            }
+        }
+
+        public static class IncrementingThread extends Thread {
+
+            private InventoryCounter inventoryCounter;
+
+            public IncrementingThread(InventoryCounter inventoryCounter) {
+                this.inventoryCounter = inventoryCounter;
+            }
+
+            @Override
+            public void run() {
+                for (int i = 0; i < 10000; i++) {
+                    inventoryCounter.increment();
+                }
+            }
+        }
+
+        private static class InventoryCounter {
+            private int items = 0;
+            private final Object lock = new Object();  // Lock object for synchronization
+
+            public void increment() {
+                synchronized (lock) {
+                    items++;
+                }
+            }
+
+            public void decrement() {
+                synchronized (lock) {
+                    items--;
+                }
+            }
+
+            public int getItems() {
+                synchronized (lock) {
+                    return items;
+                }
+            }
+        }
+    }

app/src/main/java/com/crio/threads/inventorycountersynchronizedmethods/App.java

+    package com.crio.threads.inventorycountersynchronizedmethods;
+
+    public class App {
+        public static void main(String[] args) throws InterruptedException {
+            InventoryCounter inventoryCounter = new InventoryCounter();
+            IncrementingThread incrementingThread = new IncrementingThread(inventoryCounter);
+            DecrementingThread decrementingThread = new DecrementingThread(inventoryCounter);
+
+            incrementingThread.start();
+            decrementingThread.start();
+
+            incrementingThread.join();
+            decrementingThread.join();
+
+            System.out.println("We currently have " + inventoryCounter.getItems() + " items");
+        }
+
+        public static class DecrementingThread extends Thread {
+
+            private InventoryCounter inventoryCounter;
+
+            public DecrementingThread(InventoryCounter inventoryCounter) {
+                this.inventoryCounter = inventoryCounter;
+            }
+
+            @Override
+            public void run() {
+                for (int i = 0; i < 10000; i++) {
+                    inventoryCounter.decrement();
+                }
+            }
+        }
+
+        public static class IncrementingThread extends Thread {
+
+            private InventoryCounter inventoryCounter;
+
+            public IncrementingThread(InventoryCounter inventoryCounter) {
+                this.inventoryCounter = inventoryCounter;
+            }
+
+            @Override
+            public void run() {
+                for (int i = 0; i < 10000; i++) {
+                    inventoryCounter.increment();
+                }
+            }
+        }
+
+        private static class InventoryCounter {
+            private int items = 0;
+
+            public synchronized void increment() {
+                items++;
+            }
+
+            public synchronized void decrement() {
+                items--;
+            }
+
+            public synchronized int getItems() {
+                return items;
+            }
+        }
+    }

app/src/main/java/com/crio/threads/parkinglot/App.java

+package com.crio.threads.parkinglot;
+
+import java.util.concurrent.Semaphore;
+
+// In this example, the ParkingLot class uses a Semaphore to control access to the parking spaces. 
+// Each thread representing a car tries to acquire a permit from the semaphore (semaphore.acquire()) before entering the parking lot. 
+// Once the car exits the parking lot, it releases the permit (semaphore.release()).
+
+public class App {
+
+    public static void main(String[] args) {
+        ParkingLot parkingLot = new ParkingLot(3); // 3 parking spaces available
+
+        // Create multiple car threads trying to enter the parking lot
+        for (int i = 1; i <= 5; i++) {
+            CarThread carThread = new CarThread(parkingLot, "Car " + i);
+            carThread.start();
+        }
+    }
+    
+    private static class CarThread extends Thread {
+        private ParkingLot parkingLot;
+        private String carName;
+    
+        public CarThread(ParkingLot parkingLot, String carName) {
+            this.parkingLot = parkingLot;
+            this.carName = carName;
+        }
+    
+        @Override
+        public void run() {
+            parkingLot.enter(carName);
+        }
+    }
+
+    private static class ParkingLot {
+        private Semaphore semaphore;
+
+        public ParkingLot(int capacity) {
+            semaphore = new Semaphore(capacity);
+        }
+
+        public void enter(String carName) {
+            try {
+                semaphore.acquire();
+                System.out.println(carName + " entered the parking lot. Available spaces: " + semaphore.availablePermits());
+                Thread.sleep(2000); // Simulate time spent in parking
+            } catch (InterruptedException e) {
+                e.printStackTrace();
+            } finally {
+                semaphore.release();
+                System.out.println(carName + " exited the parking lot. Available spaces: " + semaphore.availablePermits());
+            }
+        }
+    }
+
+}

app/src/main/java/com/crio/threads/producerconsumer/App.java

+package com.crio.threads.producerconsumer;
+
+import java.util.LinkedList;
+
+public class App {
+    
+    public static void main(String[] args) {
+        LinkedList<Integer> buffer = new LinkedList<>();
+        int bufferSize = 5;
+
+        Producer producer = new Producer(buffer, bufferSize);
+        Consumer consumer = new Consumer(buffer);
+
+        Thread producerThread = new Thread(producer);
+        Thread consumerThread = new Thread(consumer);
+
+        producerThread.start();
+        consumerThread.start();
+    }
+
+
+    private static class Producer implements Runnable {
+        private final LinkedList<Integer> buffer;
+        private final int SIZE;
+    
+        public Producer(LinkedList<Integer> buffer, int size) {
+            this.buffer = buffer;
+            this.SIZE = size;
+        }
+    
+        @Override
+        public void run() {
+            int value = 0;
+            while (true) {
+                synchronized (buffer) {
+                    // Wait if the buffer is full
+                    while (buffer.size() == SIZE) {
+                        try {
+                            System.out.println("Buffer is full, producer is waiting...");
+                            buffer.wait(); // The producer will wait until notified by the consumer
+                        } catch (InterruptedException e) {
+                            e.printStackTrace();
+                        }
+                    }
+
+                    // Simulate time taken to produce an item
+                    try {
+                        Thread.sleep(500); // Simulate delay in production
+                    } catch (InterruptedException e) {
+                        e.printStackTrace();
+                    }
+        
+                    // Produce the item
+                    buffer.add(value);
+                    System.out.println("Produced: " + value++);
+                    
+                    // Notify the consumer that there is an item to consume
+                    buffer.notify();
+                }
+            }
+        }
+    }
+
+    private static class Consumer implements Runnable {
+        private final LinkedList<Integer> buffer;
+
+        public Consumer(LinkedList<Integer> buffer) {
+            this.buffer = buffer;
+        }
+
+        @Override
+        public void run() {
+            while (true) {
+                synchronized (buffer) {
+                    // Wait if the buffer is empty
+                    while (buffer.isEmpty()) {
+                        try {
+                            System.out.println("Buffer is empty, consumer is waiting...");
+                            buffer.wait(); // The consumer will wait until notified by the producer
+                        } catch (InterruptedException e) {
+                            e.printStackTrace();
+                        }
+                    }
+
+                    // Simulate time taken to consume an item
+                    try {
+                        Thread.sleep(1000); // Simulate delay in consumption
+                    } catch (InterruptedException e) {
+                        e.printStackTrace();
+                    }
+
+                    // Consume the item
+                    int value = buffer.removeFirst();
+                    System.out.println("Consumed: " + value);
+                    
+                    // Notify the producer that there is space available in the buffer
+                    buffer.notify();
+                }
+            }
+        }
+    }
+}
\ No newline at end of file

app/src/main/java/com/crio/threads/producerconsumerblockingqueue/App.java

+package com.crio.threads.producerconsumerblockingqueue;
+
+import java.util.concurrent.ArrayBlockingQueue;
+import java.util.concurrent.BlockingQueue;
+
+public class App {
+    
+    public static void main(String[] args) {
+        // Create a BlockingQueue with a fixed capacity of 5
+        BlockingQueue<Integer> queue = new ArrayBlockingQueue<>(5);
+
+        // Create multiple producers and consumers
+        Thread producer = new Thread(new Producer(queue));
+        Thread consumer = new Thread(new Consumer(queue));
+
+        // Start the threads
+        producer.start();
+        consumer.start();
+    }
+
+
+    private static class Producer implements Runnable {
+        private final BlockingQueue<Integer> queue;
+    
+        public Producer(BlockingQueue<Integer> queue) {
+            this.queue = queue;
+        }
+    
+        @Override
+        public void run() {
+            int value = 0;
+            try {
+                while (true) {
+                    System.out.println("Produced: " + value);
+                    queue.put(value++); // Blocks if the queue is full
+                    Thread.sleep(500); // Sleep to simulate production delay
+                }
+            } catch (InterruptedException e) {
+                Thread.currentThread().interrupt();
+                e.printStackTrace();
+            }
+        }
+    }
+
+
+
+    private static class Consumer implements Runnable {
+        private final BlockingQueue<Integer> queue;
+
+        public Consumer(BlockingQueue<Integer> queue) {
+            this.queue = queue;
+        }
+
+        @Override
+        public void run() {
+            try {
+                while (true) {
+                    int value = queue.take(); // Blocks if the queue is empty
+                    System.out.println("Consumed: " + value);
+                    Thread.sleep(1000); // Sleep to simulate consumption delay
+                }
+            } catch (InterruptedException e) {
+                Thread.currentThread().interrupt();
+                e.printStackTrace();
+            }
+        }
+    }
+}
\ No newline at end of file

app/src/main/java/com/crio/threads/restaurant/App.java

+package com.crio.threads.restaurant;
+
+import java.util.concurrent.locks.Lock;
+import java.util.concurrent.locks.ReentrantLock;
+
+// In this example, the Restaurant class uses a ReentrantLock named lock to control access to the bookTable() method. 
+// Only one thread can acquire the lock at a time, ensuring that the table booking process is thread-safe and prevents overbooking.
+
+public class App {
+    public static void main(String[] args) throws InterruptedException {
+        Restaurant restaurant = new Restaurant();
+
+        // Create multiple customer threads
+        CustomerThread customer1 = new CustomerThread(restaurant, "Alice");
+        CustomerThread customer2 = new CustomerThread(restaurant, "Bob");
+        CustomerThread customer3 = new CustomerThread(restaurant, "John");
+
+        // Start the customer threads
+        customer1.start();
+        customer2.start();
+        customer3.start();
+    }
+
+    
+
+    private static class CustomerThread extends Thread {
+        private Restaurant restaurant;
+        private String customerName;
+    
+        public CustomerThread(Restaurant restaurant, String customerName) {
+            this.restaurant = restaurant;
+            this.customerName = customerName;
+        }
+    
+        @Override
+        public void run() {
+            restaurant.bookTable(customerName);
+        }
+    }
+
+    private static class Restaurant {
+        private int availableTables = 5; // Total number of available tables
+        private Lock lock = new ReentrantLock();
+    
+        public void bookTable(String customerName) {
+            lock.lock();
+            try {
+                if (availableTables > 0) {
+                    availableTables--;
+                    System.out.println(customerName + " booked a table. Available tables: " + availableTables);
+                } else {
+                    System.out.println("Sorry, no tables available for " + customerName);
+                }
+            } finally {
+                lock.unlock();
+            }
+        }
+    }
+}

app/src/main/java/com/crio/threads/smartfan/App.java

+package com.crio.threads.smartfan;
+
+public class App {
+
+        private static boolean fanOn = false; // Control flag for fan status
+        // private static volatile boolean fanOn = false; // Control flag for fan status
+    
+        public static void main(String[] args) throws InterruptedException {
+    
+            Thread fanThread = new Thread(() -> {
+                // Fan thread that keeps running as long as the fanOn flag is true
+                while (!fanOn) {
+                    // Wait for the signal to turn on the fan
+                }
+    
+                System.out.println("Fan is ON! Cooling the room...");
+    
+                while (fanOn) {
+                    // Fan is running
+                    try {
+                        Thread.sleep(500); // Simulate the fan working
+                    } catch (InterruptedException e) {
+                        Thread.currentThread().interrupt();
+                    }
+                }
+    
+                System.out.println("Fan is OFF! Stopping the fan...");
+            });
+    
+            fanThread.start();
+    
+            // Simulate user interaction
+            Thread.sleep(1000);
+            System.out.println("User: Turning the fan ON...");
+            fanOn = true;
+    
+            Thread.sleep(5000);  // Let the fan run for 5 seconds
+            System.out.println("User: Turning the fan OFF...");
+            fanOn = false;
+    
+            // Ensure the fan thread completes before exiting the main thread
+            fanThread.join();
+        }
+}

app/src/test/java/com/crio/threads/AppTest.java

+/*
+ * This Java source file was generated by the Gradle 'init' task.
+ */
+package com.crio.threads;
+
+import org.junit.jupiter.api.Test;
+import static org.junit.jupiter.api.Assertions.*;
+
+class AppTest {
+    @Test void appHasAGreeting() {
+        App classUnderTest = new App();
+        assertNotNull(classUnderTest.getGreeting(), "app should have a greeting");
+    }
+}

gradle/wrapper/gradle-wrapper.properties

+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-7.4.2-bin.zip
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists

gradlew

+#!/bin/sh
+
+#
+# Copyright © 2015-2021 the original authors.
+#
+# 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
+#
+#      https://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.
+#
+
+##############################################################################
+#
+#   Gradle start up script for POSIX generated by Gradle.
+#
+#   Important for running:
+#
+#   (1) You need a POSIX-compliant shell to run this script. If your /bin/sh is
+#       noncompliant, but you have some other compliant shell such as ksh or
+#       bash, then to run this script, type that shell name before the whole
+#       command line, like:
+#
+#           ksh Gradle
+#
+#       Busybox and similar reduced shells will NOT work, because this script
+#       requires all of these POSIX shell features:
+#         * functions;
+#         * expansions «$var», «${var}», «${var:-default}», «${var+SET}»,
+#           «${var#prefix}», «${var%suffix}», and «$( cmd )»;
+#         * compound commands having a testable exit status, especially «case»;
+#         * various built-in commands including «command», «set», and «ulimit».
+#
+#   Important for patching:
+#
+#   (2) This script targets any POSIX shell, so it avoids extensions provided
+#       by Bash, Ksh, etc; in particular arrays are avoided.
+#
+#       The "traditional" practice of packing multiple parameters into a
+#       space-separated string is a well documented source of bugs and security
+#       problems, so this is (mostly) avoided, by progressively accumulating
+#       options in "$@", and eventually passing that to Java.
+#
+#       Where the inherited environment variables (DEFAULT_JVM_OPTS, JAVA_OPTS,
+#       and GRADLE_OPTS) rely on word-splitting, this is performed explicitly;
+#       see the in-line comments for details.
+#
+#       There are tweaks for specific operating systems such as AIX, CygWin,
+#       Darwin, MinGW, and NonStop.
+#
+#   (3) This script is generated from the Groovy template
+#       https://github.com/gradle/gradle/blob/master/subprojects/plugins/src/main/resources/org/gradle/api/internal/plugins/unixStartScript.txt
+#       within the Gradle project.
+#
+#       You can find Gradle at https://github.com/gradle/gradle/.
+#
+##############################################################################
+
+# Attempt to set APP_HOME
+
+# Resolve links: $0 may be a link
+app_path=$0
+
+# Need this for daisy-chained symlinks.
+while
+    APP_HOME=${app_path%"${app_path##*/}"}  # leaves a trailing /; empty if no leading path
+    [ -h "$app_path" ]
+do
+    ls=$( ls -ld "$app_path" )
+    link=${ls#*' -> '}
+    case $link in             #(
+      /*)   app_path=$link ;; #(
+      *)    app_path=$APP_HOME$link ;;
+    esac
+done
+
+APP_HOME=$( cd "${APP_HOME:-./}" && pwd -P ) || exit
+
+APP_NAME="Gradle"
+APP_BASE_NAME=${0##*/}
+
+# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"'
+
+# Use the maximum available, or set MAX_FD != -1 to use that value.
+MAX_FD=maximum
+
+warn () {
+    echo "$*"
+} >&2
+
+die () {
+    echo
+    echo "$*"
+    echo
+    exit 1
+} >&2
+
+# OS specific support (must be 'true' or 'false').
+cygwin=false
+msys=false
+darwin=false
+nonstop=false
+case "$( uname )" in                #(
+  CYGWIN* )         cygwin=true  ;; #(
+  Darwin* )         darwin=true  ;; #(
+  MSYS* | MINGW* )  msys=true    ;; #(
+  NONSTOP* )        nonstop=true ;;
+esac
+
+CLASSPATH=$APP_HOME/gradle/wrapper/gradle-wrapper.jar
+
+
+# Determine the Java command to use to start the JVM.
+if [ -n "$JAVA_HOME" ] ; then
+    if [ -x "$JAVA_HOME/jre/sh/java" ] ; then
+        # IBM's JDK on AIX uses strange locations for the executables
+        JAVACMD=$JAVA_HOME/jre/sh/java
+    else
+        JAVACMD=$JAVA_HOME/bin/java
+    fi
+    if [ ! -x "$JAVACMD" ] ; then
+        die "ERROR: JAVA_HOME is set to an invalid directory: $JAVA_HOME
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+    fi
+else
+    JAVACMD=java
+    which java >/dev/null 2>&1 || die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+fi
+
+# Increase the maximum file descriptors if we can.
+if ! "$cygwin" && ! "$darwin" && ! "$nonstop" ; then
+    case $MAX_FD in #(
+      max*)
+        MAX_FD=$( ulimit -H -n ) ||
+            warn "Could not query maximum file descriptor limit"
+    esac
+    case $MAX_FD in  #(
+      '' | soft) :;; #(
+      *)
+        ulimit -n "$MAX_FD" ||
+            warn "Could not set maximum file descriptor limit to $MAX_FD"
+    esac
+fi
+
+# Collect all arguments for the java command, stacking in reverse order:
+#   * args from the command line
+#   * the main class name
+#   * -classpath
+#   * -D...appname settings
+#   * --module-path (only if needed)
+#   * DEFAULT_JVM_OPTS, JAVA_OPTS, and GRADLE_OPTS environment variables.
+
+# For Cygwin or MSYS, switch paths to Windows format before running java
+if "$cygwin" || "$msys" ; then
+    APP_HOME=$( cygpath --path --mixed "$APP_HOME" )
+    CLASSPATH=$( cygpath --path --mixed "$CLASSPATH" )
+
+    JAVACMD=$( cygpath --unix "$JAVACMD" )
+
+    # Now convert the arguments - kludge to limit ourselves to /bin/sh
+    for arg do
+        if
+            case $arg in                                #(
+              -*)   false ;;                            # don't mess with options #(
+              /?*)  t=${arg#/} t=/${t%%/*}              # looks like a POSIX filepath
+                    [ -e "$t" ] ;;                      #(
+              *)    false ;;
+            esac
+        then
+            arg=$( cygpath --path --ignore --mixed "$arg" )
+        fi
+        # Roll the args list around exactly as many times as the number of
+        # args, so each arg winds up back in the position where it started, but
+        # possibly modified.
+        #
+        # NB: a `for` loop captures its iteration list before it begins, so
+        # changing the positional parameters here affects neither the number of
+        # iterations, nor the values presented in `arg`.
+        shift                   # remove old arg
+        set -- "$@" "$arg"      # push replacement arg
+    done
+fi
+
+# Collect all arguments for the java command;
+#   * $DEFAULT_JVM_OPTS, $JAVA_OPTS, and $GRADLE_OPTS can contain fragments of
+#     shell script including quotes and variable substitutions, so put them in
+#     double quotes to make sure that they get re-expanded; and
+#   * put everything else in single quotes, so that it's not re-expanded.
+
+set -- \
+        "-Dorg.gradle.appname=$APP_BASE_NAME" \
+        -classpath "$CLASSPATH" \
+        org.gradle.wrapper.GradleWrapperMain \
+        "$@"
+
+# Use "xargs" to parse quoted args.
+#
+# With -n1 it outputs one arg per line, with the quotes and backslashes removed.
+#
+# In Bash we could simply go:
+#
+#   readarray ARGS < <( xargs -n1 <<<"$var" ) &&
+#   set -- "${ARGS[@]}" "$@"
+#
+# but POSIX shell has neither arrays nor command substitution, so instead we
+# post-process each arg (as a line of input to sed) to backslash-escape any
+# character that might be a shell metacharacter, then use eval to reverse
+# that process (while maintaining the separation between arguments), and wrap
+# the whole thing up as a single "set" statement.
+#
+# This will of course break if any of these variables contains a newline or
+# an unmatched quote.
+#
+
+eval "set -- $(
+        printf '%s\n' "$DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS" |
+        xargs -n1 |
+        sed ' s~[^-[:alnum:]+,./:=@_]~\\&~g; ' |
+        tr '\n' ' '
+    )" '"$@"'
+
+exec "$JAVACMD" "$@"

gradlew.bat

+@rem
+@rem Copyright 2015 the original author or authors.
+@rem
+@rem Licensed under the Apache License, Version 2.0 (the "License");
+@rem you may not use this file except in compliance with the License.
+@rem You may obtain a copy of the License at
+@rem
+@rem      https://www.apache.org/licenses/LICENSE-2.0
+@rem
+@rem Unless required by applicable law or agreed to in writing, software
+@rem distributed under the License is distributed on an "AS IS" BASIS,
+@rem WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+@rem See the License for the specific language governing permissions and
+@rem limitations under the License.
+@rem
+
+@if "%DEBUG%" == "" @echo off
+@rem ##########################################################################
+@rem
+@rem  Gradle startup script for Windows
+@rem
+@rem ##########################################################################
+
+@rem Set local scope for the variables with windows NT shell
+if "%OS%"=="Windows_NT" setlocal
+
+set DIRNAME=%~dp0
+if "%DIRNAME%" == "" set DIRNAME=.
+set APP_BASE_NAME=%~n0
+set APP_HOME=%DIRNAME%
+
+@rem Resolve any "." and ".." in APP_HOME to make it shorter.
+for %%i in ("%APP_HOME%") do set APP_HOME=%%~fi
+
+@rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+set DEFAULT_JVM_OPTS="-Xmx64m" "-Xms64m"
+
+@rem Find java.exe
+if defined JAVA_HOME goto findJavaFromJavaHome
+
+set JAVA_EXE=java.exe
+%JAVA_EXE% -version >NUL 2>&1
+if "%ERRORLEVEL%" == "0" goto execute
+
+echo.
+echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:findJavaFromJavaHome
+set JAVA_HOME=%JAVA_HOME:"=%
+set JAVA_EXE=%JAVA_HOME%/bin/java.exe
+
+if exist "%JAVA_EXE%" goto execute
+
+echo.
+echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME%
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:execute
+@rem Setup the command line
+
+set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar
+
+
+@rem Execute Gradle
+"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %*
+
+:end
+@rem End local scope for the variables with windows NT shell
+if "%ERRORLEVEL%"=="0" goto mainEnd
+
+:fail
+rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of
+rem the _cmd.exe /c_ return code!
+if  not "" == "%GRADLE_EXIT_CONSOLE%" exit 1
+exit /b 1
+
+:mainEnd
+if "%OS%"=="Windows_NT" endlocal
+
+:omega

settings.gradle

+/*
+ * This file was generated by the Gradle 'init' task.
+ *
+ * The settings file is used to specify which projects to include in your build.
+ *
+ * Detailed information about configuring a multi-project build in Gradle can be found
+ * in the user manual at https://docs.gradle.org/7.4.2/userguide/multi_project_builds.html
+ */
+
+rootProject.name = 'thread-synchronization'
+include('app')