Add activities for Multithreading

.gitignore

+.idea
+# Created by https://www.toptal.com/developers/gitignore/api/java,gradle
+# Edit at https://www.toptal.com/developers/gitignore?templates=java,gradle
+
+### Java ###
+# Compiled class file
+*.class
+
+# Log file
+*.log
+
+# BlueJ files
+*.ctxt
+
+# Mobile Tools for Java (J2ME)
+.mtj.tmp/
+
+# Package Files #
+*.jar
+*.war
+*.nar
+*.ear
+*.zip
+*.tar.gz
+*.rar
+
+# virtual machine crash logs, see http://www.java.com/en/download/help/error_hotspot.xml
+hs_err_pid*
+replay_pid*
+
+### Gradle ###
+.gradle
+**/build/
+!src/**/build/
+
+# Ignore Gradle GUI config
+gradle-app.setting
+
+# Avoid ignoring Gradle wrapper jar file (.jar files are usually ignored)
+!gradle-wrapper.jar
+
+# Avoid ignore Gradle wrappper properties
+!gradle-wrapper.properties
+
+# Cache of project
+.gradletasknamecache
+
+# Eclipse Gradle plugin generated files
+# Eclipse Core
+.project
+# JDT-specific (Eclipse Java Development Tools)
+.classpath
+
+### Gradle Patch ###
+# Java heap dump
+*.hprof
+
+# End of https://www.toptal.com/developers/gitignore/api/java,gradle
+
+*.jpg
\ No newline at end of file

build.gradle

+plugins {
+    id 'java'
+}
+
+group 'com.criodo'
+version '1.0-SNAPSHOT'
+
+repositories {
+    mavenCentral()
+}
+
+dependencies {
+    testImplementation 'org.junit.jupiter:junit-jupiter-api:5.8.1'
+    testRuntimeOnly 'org.junit.jupiter:junit-jupiter-engine:5.8.1'
+}
+
+test {
+    useJUnitPlatform()
+}
\ No newline at end of file

gradle/wrapper/gradle-wrapper.properties

+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-7.4-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

+rootProject.name = 'intro-to-multithreading'
+

src/main/java/com/criodo/Activity1/FileResourcesUtils.java

+package com.criodo.Activity1;
+
+import java.io.BufferedReader;
+import java.io.File;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.net.URISyntaxException;
+import java.net.URL;
+import java.nio.charset.StandardCharsets;
+import java.nio.file.Files;
+import java.util.List;
+
+public class FileResourcesUtils {
+
+    public static void main(String[] args) throws IOException, URISyntaxException {
+
+        FileResourcesUtils app = new FileResourcesUtils();
+
+        //String fileName = "database.properties";
+        String fileName = "json/file1.json";
+
+        System.out.println("getResourceAsStream : " + fileName);
+        InputStream is = app.getFileFromResourceAsStream(fileName);
+        printInputStream(is);
+
+        System.out.println("\ngetResource : " + fileName);
+        File file = app.getFileFromResource(fileName);
+        printFile(file);
+
+    }
+
+    // get a file from the resources folder
+    // works everywhere, IDEA, unit test and JAR file.
+    public InputStream getFileFromResourceAsStream(String fileName) {
+
+        // The class loader that loaded the class
+        ClassLoader classLoader = getClass().getClassLoader();
+        InputStream inputStream = classLoader.getResourceAsStream(fileName);
+
+        // the stream holding the file content
+        if (inputStream == null) {
+            throw new IllegalArgumentException("file not found! " + fileName);
+        } else {
+            return inputStream;
+        }
+
+    }
+
+    /*
+        The resource URL is not working in the JAR
+        If we try to access a file that is inside a JAR,
+        It throws NoSuchFileException (linux), InvalidPathException (Windows)
+
+        Resource URL Sample: file:java-io.jar!/json/file1.json
+     */
+    public File getFileFromResource(String fileName) throws URISyntaxException{
+
+        ClassLoader classLoader = getClass().getClassLoader();
+        URL resource = classLoader.getResource(fileName);
+        if (resource == null) {
+            throw new IllegalArgumentException("file not found! " + fileName);
+        } else {
+
+            // failed if files have whitespaces or special characters
+            //return new File(resource.getFile());
+
+            return new File(resource.toURI());
+        }
+
+    }
+
+    // print input stream
+    public static void printInputStream(InputStream is) {
+
+        try (InputStreamReader streamReader =
+                    new InputStreamReader(is, StandardCharsets.UTF_8);
+             BufferedReader reader = new BufferedReader(streamReader)) {
+
+            String line;
+            while ((line = reader.readLine()) != null) {
+                System.out.println(line);
+            }
+
+        } catch (IOException e) {
+            e.printStackTrace();
+        }
+
+    }
+
+    // print a file
+    public static void printFile(File file) {
+
+        List<String> lines;
+        try {
+            lines = Files.readAllLines(file.toPath(), StandardCharsets.UTF_8);
+            lines.forEach(System.out::println);
+        } catch (IOException e) {
+            e.printStackTrace();
+        }
+
+    }
+
+}
+

src/main/java/com/criodo/Activity1/Main.java

+package com.criodo.Activity1;
+
+import java.io.File;
+import java.io.IOException;
+import java.net.URISyntaxException;
+import java.util.ArrayList;
+import java.util.List;
+
+import java.awt.image.BufferedImage;
+
+import javax.imageio.ImageIO;
+
+public class Main {
+    
+    public static final String FILE_SLUG = "HIGH";
+    public static final String FILE_EXTENSION = ".jpg";
+    
+
+    public static void main(String[] args) throws IOException, URISyntaxException {
+        long startTime = 0;
+        long endTime = 0;
+        long duration = 0;
+        int numberOfThreads = 12; // Should be strictly > 0
+
+        FileResourcesUtils app = new FileResourcesUtils();
+        File file = app.getFileFromResource(FILE_SLUG + FILE_EXTENSION);
+
+        BufferedImage originalImage = ImageIO.read(file);
+        BufferedImage resultImage = new BufferedImage(originalImage.getWidth(), originalImage.getHeight(), BufferedImage.TYPE_INT_RGB);
+
+        startTime = System.currentTimeMillis();
+        recolorSingleThreaded(originalImage, resultImage);
+        endTime = System.currentTimeMillis();
+        duration = endTime - startTime;
+
+        File outputFile = new File(FILE_SLUG + "-INVERT" + "-" + 1 + FILE_EXTENSION);
+        ImageIO.write(resultImage, "jpg", outputFile);
+
+        System.out.println("Single Thread Duration: " + duration);
+
+        startTime = System.currentTimeMillis();
+        recolorMultithreaded(originalImage, resultImage, numberOfThreads);
+        endTime = System.currentTimeMillis();
+        duration = endTime - startTime;
+
+        outputFile = new File(FILE_SLUG + "-INVERT" + "-" + numberOfThreads + FILE_EXTENSION);
+        ImageIO.write(resultImage, "jpg", outputFile);
+
+        System.out.println("Number of Threads: " + numberOfThreads + " Multi Thread Duration: " + duration);
+ 
+    }
+
+    public static void recolorMultithreaded(BufferedImage originalImage, BufferedImage resultImage, int numberOfThreads) {
+        List<Thread> threads = new ArrayList<>();
+        int width = originalImage.getWidth();
+        int height = originalImage.getHeight() / numberOfThreads;
+        Thread thread;
+
+        for(int i = 0; i < numberOfThreads ; i++) {
+            final int threadMultiplier = i;
+            thread = new Thread(() -> {
+                invertImage(originalImage, resultImage, 0, (height * threadMultiplier), width, height);
+            });
+
+            threads.add(thread);
+            thread.start();
+        }
+
+        for(Thread t : threads) {
+            try {
+                t.join();
+            } catch (InterruptedException ignored) {
+            }
+        }
+    }
+
+    public static void recolorSingleThreaded(BufferedImage originalImage, BufferedImage resultImage) {
+        invertImage(originalImage, resultImage, 0, 0, originalImage.getWidth(), originalImage.getHeight());
+    }
+
+    public static void invertImage(BufferedImage originalImage, BufferedImage resultImage, int leftCorner, int topCorner,
+    int width, int height){
+        for(int x = leftCorner ; x < leftCorner + width && x < originalImage.getWidth() ; x++) {
+            for(int y = topCorner ; y < topCorner + height && y < originalImage.getHeight() ; y++) {
+                int in = originalImage.getRGB(x, y);
+                resultImage.setRGB(x,y,(in & 0xff000000) | ((~in) & 0x00ffffff));
+            }
+        }
+    }
+}

src/main/java/com/criodo/Activity2/CustomThread.java

+package com.criodo.Activity2;
+
+public class CustomThread implements Runnable {
+    
+    @Override
+    public void run() {
+        // moving thread2 to timed waiting state
+        try {
+         Thread.sleep(1500);
+        } catch (InterruptedException e) {
+         e.printStackTrace();
+        }
+      
+        System.out.println(
+          "State of " + ThreadLifeCycle.thread1.getName() + " while it called join() method on " + Thread.currentThread().getName() + "-" + ThreadLifeCycle.thread1.getState());
+        try {
+         Thread.sleep(200);
+        } catch (InterruptedException e) {
+         e.printStackTrace();
+        }
+       }
+}

src/main/java/com/criodo/Activity2/PrintNumbersRunnable.java

+package com.criodo.Activity2;
+
+import java.util.stream.IntStream;
+
+public class PrintNumbersRunnable implements Runnable {
+
+    @Override
+    public void run() {
+   
+     IntStream.range(1, 11).forEach(n -> System.out.println(Thread.currentThread().getName() + " - " + n));
+   
+    }
+}

src/main/java/com/criodo/Activity2/PrintNumbersThread.java

+package com.criodo.Activity2;
+
+import java.util.stream.IntStream;
+
+public class PrintNumbersThread extends Thread {
+
+    @Override
+    public void run() {
+   
+     IntStream.range(1, 11).forEach(n -> System.out.println(Thread.currentThread().getName() + " - " + n));
+   
+    }
+}

src/main/java/com/criodo/Activity2/ThreadExtendsClass.java

+package com.criodo.Activity2;
+
+public class ThreadExtendsClass {
+    public static void main(String[] args) {
+
+        PrintNumbersThread numbers1 = new PrintNumbersThread();
+        numbers1.setName("PrintNumbers Thread 1");
+        numbers1.start();
+      
+        PrintNumbersThread numbers2 = new PrintNumbersThread();
+        numbers2.setName("PrintNumbers Thread 2");
+        numbers2.start();
+      
+       }
+}

src/main/java/com/criodo/Activity2/ThreadImplementsRunnable.java

+package com.criodo.Activity2;
+
+public class ThreadImplementsRunnable {
+    public static void main(String[] args) {
+
+        PrintNumbersRunnable numberRunnableThread = new PrintNumbersRunnable();
+      
+        Thread t1 = new Thread(numberRunnableThread);
+        t1.setName("Runnable Thread 1");
+        t1.start();
+      
+        Thread t2 = new Thread(numberRunnableThread);
+        t2.setName("Runnable Thread 2");
+        t2.start();
+      
+       }
+}

src/main/java/com/criodo/Activity2/ThreadJoinExample.java

+package com.criodo.Activity2;
+
+public class ThreadJoinExample {
+
+        public static void main(String[] args) throws InterruptedException {
+         System.out.println("main thread started execution. Current thread name : " + Thread.currentThread().getName());
+         PrintNumbers t1 = new PrintNumbers(1, 10);
+         PrintNumbers t2 = new PrintNumbers(11, 20);
+         PrintNumbers t3 = new PrintNumbers(21, 30);
+       
+         t1.start();
+         //t1.join();
+       
+         t2.start();
+         //t2.join();
+       
+         t3.start();
+         //t3.join();
+       
+         System.out.println("All threads completed excution.");
+         System.out.println(Thread.currentThread().getName() + " complete execution");
+        }
+       
+       }
+       
+       class PrintNumbers extends Thread {
+       
+        private int start;
+        private int end;
+       
+        public PrintNumbers(int start, int end) {
+         this.start = start;
+         this.end = end;
+        }
+       
+        @Override
+        public void run() {
+         for (int i = start; i <= end; i++) {
+          System.out.println(Thread.currentThread().getName() + " - " + i);
+         }
+         System.out.println(Thread.currentThread().getName() + " thread execution completed.");
+        }
+}

src/main/java/com/criodo/Activity2/ThreadLifeCycle.java

+package com.criodo.Activity2;
+
+public class ThreadLifeCycle implements Runnable{
+
+
+
+ public static Thread thread1;
+ public static ThreadLifeCycle threadLifeCycle;
+
+ public static void main(String[] args) {
+
+  threadLifeCycle = new ThreadLifeCycle();
+  thread1 = new Thread(threadLifeCycle);
+  thread1.setName("Thread #1");
+
+  System.out.println(Thread.currentThread().getName());
+
+  // thread1 created and is currently in the NEW state.
+  System.out.println("State of " + thread1.getName() + " after creating it - " + thread1.getState());
+  thread1.start();
+
+  // thread1 moved to Runnable state
+  System.out.println("State of " + thread1.getName() + " after calling start() method on it - " + thread1.getState());
+
+ }
+
+ @Override
+ public void run() {
+  CustomThread customThread = new CustomThread();
+  Thread thread2 = new Thread(customThread);
+  thread2.setName("Thread #2");
+
+  // thread1 created and is currently in the NEW state.
+  System.out.println("State of " + thread2.getName() + " after creating it - " + thread2.getState());
+  thread2.start();
+
+  // thread2 moved to Runnable state
+  System.out.println("State of " + thread2.getName() + " after calling start() method on it - " + thread2.getState());
+
+  // moving thread1 to timed waiting state
+  try {
+   // moving thread1 to timed waiting state
+   Thread.sleep(200);
+  } catch (InterruptedException e) {
+   e.printStackTrace();
+  }
+  System.out.println("State of " + thread2.getName() + " after calling sleep() method on it - " + thread2.getState());
+
+  try {
+   // waiting for thread2 to die / complete it's execution
+   thread2.join();
+  } catch (InterruptedException e) {
+   e.printStackTrace();
+  }
+  System.out.println("State of " + thread2.getName() + " when it has finished it's execution - " + thread2.getState());
+ }
+
+}

src/main/java/com/criodo/Activity3/ThreadPerformanceDemo.java

+package com.criodo.Activity3;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.concurrent.atomic.AtomicInteger;
+
+public class ThreadPerformanceDemo {
+    public static void main(String[] args) {
+        // Number of threads to create
+        int numThreads1 = 4;
+        int numThreads2 = 1000;
+        int[] numbers = generateNumbers(10000); // Generate an array of numbers
+
+        long startTime = System.currentTimeMillis();
+        int result1 = computeSumUsingThreads(numbers, numThreads1);
+        long endTime = System.currentTimeMillis();
+        long executionTime = endTime - startTime;
+        System.out.printf("Thread count: %d \nResult: %d \nExecution time: %d ms\n\n", numThreads1, result1, executionTime);
+
+        long startTime2 = System.currentTimeMillis();
+        int result2 = computeSumUsingThreads(numbers, numThreads2);
+        long endTime2 = System.currentTimeMillis();
+        long executionTime2 = endTime2 - startTime2;
+        System.out.printf("Thread count: %d \nResult: %d \nExecution time: %d ms\n\n", numThreads2, result2, executionTime2);
+    }
+
+    static int[] generateNumbers(int size) {
+        int[] numbers = new int[size];
+        for (int i = 0; i < size; i++) {
+            numbers[i] = i;
+        }
+        return numbers;
+    }
+
+    static int computeSumUsingThreads(int[] numbers, int numThreads) {
+        int chunkSize = numbers.length / numThreads;
+        AtomicInteger result = new AtomicInteger();
+
+        List<Thread> threads = new ArrayList<>();
+
+        for (int i = 0; i < numThreads; i++) {
+            int startIndex = i * chunkSize;
+            int endIndex = (i == numThreads - 1) ? numbers.length : (i + 1) * chunkSize;
+
+            Thread thread = new Thread(() -> {
+                int localSum = 0;
+                for (int j = startIndex; j < endIndex; j++) {
+                    localSum += numbers[j];
+                }
+                synchronized (ThreadPerformanceDemo.class) {
+                    result.addAndGet(localSum); // Synchronize access to the result
+                }
+            });
+
+            threads.add(thread);
+            thread.start();
+        }
+
+        // Wait for all threads to complete
+        for (Thread thread : threads) {
+            try {
+                thread.join();
+            } catch (InterruptedException e) {
+                e.printStackTrace();
+            }
+        }
+
+        return result.get();
+    }
+}
+