diff --git a/.github/workflows/check_lesson_16_java_pr.yaml b/.github/workflows/check_lesson_16_java_pr.yaml
new file mode 100644
index 000000000..af358e2cb
--- /dev/null
+++ b/.github/workflows/check_lesson_16_java_pr.yaml
@@ -0,0 +1,28 @@
+name: Check Lesson 16 Java Pull Request
+
+on:
+  pull_request:
+    branches: [ "main" ]
+    paths:
+      - "lesson_16/objects/**"
+
+jobs:
+  build:
+
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+      pull-requests: write
+
+    steps:
+    - uses: actions/checkout@v4
+
+    - name: Set up JDK 17
+      uses: actions/setup-java@v4
+      with:
+        java-version: '17'
+        distribution: 'temurin'
+
+    - name: Build Lesson 16 with Java
+      working-directory: ./lesson_16/objects
+      run: ./gradlew check
\ No newline at end of file
diff --git a/.github/workflows/check_lesson_17_java_pr.yaml b/.github/workflows/check_lesson_17_java_pr.yaml
new file mode 100644
index 000000000..14cdac96c
--- /dev/null
+++ b/.github/workflows/check_lesson_17_java_pr.yaml
@@ -0,0 +1,28 @@
+name: Check Lesson 17 Java Pull Request
+
+on:
+  pull_request:
+    branches: [ "main" ]
+    paths:
+      - "lesson_17/oop/**"
+
+jobs:
+  build:
+
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+      pull-requests: write
+
+    steps:
+    - uses: actions/checkout@v4
+
+    - name: Set up JDK 17
+      uses: actions/setup-java@v4
+      with:
+        java-version: '17'
+        distribution: 'temurin'
+
+    - name: Build Lesson 17 with Java
+      working-directory: ./lesson_17/oop
+      run: ./gradlew check
\ No newline at end of file
diff --git a/lesson_16/README.md b/lesson_16/README.md
index 8e3346f55..cc1a5d7e5 100644
--- a/lesson_16/README.md
+++ b/lesson_16/README.md
@@ -10,4 +10,26 @@ Please review the following resources before lecture:
 
 ## Homework
 
-TODO(anthonydmays): Add details
\ No newline at end of file
+- [ ] Complete [Custom Data Types](#custom-data-types) assignment.
+- [ ] Do pre-work for [lesson 17](/lesson_17/).
+
+## Custom Data Types
+
+For this assignment, you will need to pull together everything that you've learned up to this point to design and create your own data types. Again, remember to use the [Conventional Commits][conventional-commits] spec for your commit messages and pull requests.
+
+1. Create a sub-folder in the main [app folder][lesson16-folder] with a unique name for your work.
+2. Design at least one custom class that represents a real-world object.
+    * The class must have at least 5 member variables of at least 3 different types. One of the member variables must be a collection type (Array, ArrayList, etc.).
+    * You must also incorporate an enum type as well.
+    * The class must have at least one constructor.
+    * The class must have at least 3 member functions.
+    * One of your functions must make use of a conditional expression.
+    * One of your functions must make use of your collection member variable.
+    * One of your functions must make use of a loop.
+    * You must use at least one custom exception.
+3. Create a matching subfolder in the [test folder][test-folder] and a test file. Your test must include at least 5 test methods.
+
+[lesson16-folder]: ./objects/objects_app/src/main/java/com/codedifferently/lesson16/
+[test-folder]: ./objects/objects_app/src/test/java/com/codedifferently/lesson16/
+[conventional-commits]: https://www.conventionalcommits.org/en/v3.0.0/
+
diff --git a/lesson_16/objects/.gitattributes b/lesson_16/objects/.gitattributes
new file mode 100644
index 000000000..097f9f98d
--- /dev/null
+++ b/lesson_16/objects/.gitattributes
@@ -0,0 +1,9 @@
+#
+# https://help.github.com/articles/dealing-with-line-endings/
+#
+# Linux start script should use lf
+/gradlew        text eol=lf
+
+# These are Windows script files and should use crlf
+*.bat           text eol=crlf
+
diff --git a/lesson_16/objects/.gitignore b/lesson_16/objects/.gitignore
new file mode 100644
index 000000000..1b6985c00
--- /dev/null
+++ b/lesson_16/objects/.gitignore
@@ -0,0 +1,5 @@
+# Ignore Gradle project-specific cache directory
+.gradle
+
+# Ignore Gradle build output directory
+build
diff --git a/lesson_16/objects/gradle/wrapper/gradle-wrapper.jar b/lesson_16/objects/gradle/wrapper/gradle-wrapper.jar
new file mode 100644
index 000000000..ccebba771
Binary files /dev/null and b/lesson_16/objects/gradle/wrapper/gradle-wrapper.jar differ
diff --git a/lesson_16/objects/gradle/wrapper/gradle-wrapper.properties b/lesson_16/objects/gradle/wrapper/gradle-wrapper.properties
new file mode 100644
index 000000000..bdc9a83b1
--- /dev/null
+++ b/lesson_16/objects/gradle/wrapper/gradle-wrapper.properties
@@ -0,0 +1,6 @@
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-8.0.2-bin.zip
+networkTimeout=10000
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists
diff --git a/lesson_16/objects/gradlew b/lesson_16/objects/gradlew
new file mode 100755
index 000000000..79a61d421
--- /dev/null
+++ b/lesson_16/objects/gradlew
@@ -0,0 +1,244 @@
+#!/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/HEAD/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
+
+# This is normally unused
+# shellcheck disable=SC2034
+APP_BASE_NAME=${0##*/}
+APP_HOME=$( cd "${APP_HOME:-./}" && pwd -P ) || exit
+
+# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"'
+
+# Use the maximum available, or set MAX_FD != -1 to use that value.
+MAX_FD=maximum
+
+warn () {
+    echo "$*"
+} >&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 $MAX_FD in #(
+      max*)
+        # In POSIX sh, ulimit -H is undefined. That's why the result is checked to see if it worked.
+        # shellcheck disable=SC3045
+        MAX_FD=$( ulimit -H -n ) ||
+            warn "Could not query maximum file descriptor limit"
+    esac
+    case $MAX_FD in  #(
+      '' | soft) :;; #(
+      *)
+        # In POSIX sh, ulimit -n is undefined. That's why the result is checked to see if it worked.
+        # shellcheck disable=SC3045
+        ulimit -n "$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 "$CLASSPATH" \
+        org.gradle.wrapper.GradleWrapperMain \
+        "$@"
+
+# Stop when "xargs" is not available.
+if ! command -v xargs >/dev/null 2>&1
+then
+    die "xargs is not available"
+fi
+
+# 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 "$JAVACMD" "$@"
diff --git a/lesson_16/objects/gradlew.bat b/lesson_16/objects/gradlew.bat
new file mode 100644
index 000000000..93e3f59f1
--- /dev/null
+++ b/lesson_16/objects/gradlew.bat
@@ -0,0 +1,92 @@
+@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=.
+@rem This is normally unused
+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% equ 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% equ 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!
+set EXIT_CODE=%ERRORLEVEL%
+if %EXIT_CODE% equ 0 set EXIT_CODE=1
+if not ""=="%GRADLE_EXIT_CONSOLE%" exit %EXIT_CODE%
+exit /b %EXIT_CODE%
+
+:mainEnd
+if "%OS%"=="Windows_NT" endlocal
+
+:omega
diff --git a/lesson_16/objects/objects_app/build.gradle.kts b/lesson_16/objects/objects_app/build.gradle.kts
new file mode 100644
index 000000000..0ce9bd266
--- /dev/null
+++ b/lesson_16/objects/objects_app/build.gradle.kts
@@ -0,0 +1,64 @@
+plugins {
+    // Apply the application plugin to add support for building a CLI application in Java.
+    application
+    eclipse
+    id("com.diffplug.spotless") version "6.25.0"
+	  id("org.springframework.boot") version "3.2.2"
+    id("com.adarshr.test-logger") version "4.0.0"
+}
+
+apply(plugin = "io.spring.dependency-management")
+
+repositories {
+    // Use Maven Central for resolving dependencies.
+    mavenCentral()
+}
+
+dependencies {
+    // Use JUnit Jupiter for testing.
+    testImplementation("com.codedifferently.instructional:instructional-lib")
+    testImplementation("org.junit.jupiter:junit-jupiter:5.9.1")
+    testImplementation("org.springframework.boot:spring-boot-starter-test")
+    testImplementation("org.assertj:assertj-core:3.25.1")
+    testImplementation("at.favre.lib:bcrypt:0.10.2")
+
+    // This dependency is used by the application.
+    implementation("com.codedifferently.instructional:instructional-lib")
+    implementation("com.google.guava:guava:31.1-jre")
+    implementation("com.google.code.gson:gson:2.10.1")
+    implementation("org.projectlombok:lombok:1.18.30")
+    implementation("org.springframework.boot:spring-boot-starter")
+}
+
+application {
+    // Define the main class for the application.
+    mainClass.set("com.codedifferently.lesson16.Lesson16")
+}
+
+tasks.named<Test>("test") {
+    // Use JUnit Platform for unit tests.
+    useJUnitPlatform()
+}
+
+
+configure<com.diffplug.gradle.spotless.SpotlessExtension> {
+
+  format("misc", {
+    // define the files to apply `misc` to
+    target("*.gradle", ".gitattributes", ".gitignore")
+
+    // define the steps to apply to those files
+    trimTrailingWhitespace()
+    indentWithTabs() // or spaces. Takes an integer argument if you don't like 4
+    endWithNewline()
+  })
+
+  java {
+    // don't need to set target, it is inferred from java
+
+    // apply a specific flavor of google-java-format
+    googleJavaFormat()
+    // fix formatting of type annotations
+    formatAnnotations()
+  }
+}
diff --git a/lesson_16/objects/objects_app/src/main/java/com/codedifferently/lesson16/Lesson16.java b/lesson_16/objects/objects_app/src/main/java/com/codedifferently/lesson16/Lesson16.java
new file mode 100644
index 000000000..fd5348f09
--- /dev/null
+++ b/lesson_16/objects/objects_app/src/main/java/com/codedifferently/lesson16/Lesson16.java
@@ -0,0 +1,15 @@
+package com.codedifferently.lesson16;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.context.annotation.Configuration;
+
+@Configuration
+@SpringBootApplication(scanBasePackages = "com.codedifferently")
+public class Lesson16 {
+
+  public static void main(String[] args) {
+    var application = new SpringApplication(Lesson16.class);
+    application.run(args);
+  }
+}
diff --git a/lesson_16/objects/objects_app/src/test/java/com/codedifferently/lesson16/Lesson16Test.java b/lesson_16/objects/objects_app/src/test/java/com/codedifferently/lesson16/Lesson16Test.java
new file mode 100644
index 000000000..c1ec54548
--- /dev/null
+++ b/lesson_16/objects/objects_app/src/test/java/com/codedifferently/lesson16/Lesson16Test.java
@@ -0,0 +1,13 @@
+package com.codedifferently.lesson16;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import org.junit.jupiter.api.Test;
+
+class Lesson16Test {
+
+  @Test
+  void testCanVote() {
+    assertThat(new Lesson16()).isNotNull();
+  }
+}
diff --git a/lesson_16/objects/settings.gradle.kts b/lesson_16/objects/settings.gradle.kts
new file mode 100644
index 000000000..3e636ca90
--- /dev/null
+++ b/lesson_16/objects/settings.gradle.kts
@@ -0,0 +1,13 @@
+/*
+ * 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/8.0.2/userguide/multi_project_builds.html
+ */
+
+includeBuild("../../lib/java/codedifferently-instructional")
+
+rootProject.name = "lesson_16"
+include("objects_app")
diff --git a/lesson_17/README.md b/lesson_17/README.md
new file mode 100644
index 000000000..dd2c37b01
--- /dev/null
+++ b/lesson_17/README.md
@@ -0,0 +1,49 @@
+# Lesson 17: OOP Principles, Part II
+
+## Pre-work
+
+Please review the following resources before lecture:
+
+### Required
+
+* [Object-oriented Programming in 7 minutes | Mosh (Video)](https://www.youtube.com/watch?v=pTB0EiLXUC8)
+* [Naming Convention In Java Tutorial #77 (Video)](https://www.youtube.com/watch?v=QazDDPtSulY)
+
+### Recommended
+
+* [Naming Conventions - Oracle (Article)](https://www.oracle.com/java/technologies/javase/codeconventions-namingconventions.html)
+* [Test-Driven Development (TDD): A Time-Tested Recipe for Quality Software (Article)](https://semaphoreci.com/blog/test-driven-development)
+
+## Homework
+
+- [ ] Complete [Library Management System](#library-management-system) assignment.
+
+## Library Management System
+
+For this assignment, you will build a library management system using object oriented principles. Pay attention to the requirements careful in order to implement your system successfully.
+
+### Functional Requirements
+
+* We want to define a book and keep track of its title, isbn, author(s), number of pages, and whether it is checked out or not.
+* We want define a patron with properties including their name and the books they have checked out.
+* We want to define a library that:
+    * Allows us to add/remove a book to and from its collection of books. 
+    * Allows us to register new patrons
+    * Allows us to check out books to patrons.
+    * Allows us to return books from patrons.
+
+### Technical Requirements
+
+* All of your types must be created in a unique sub-package under the `com.codedifferently.lesson17` namespace.
+* Include tests for all of your classes and public methods.
+* Include appropriate `javadoc` for your classes and methods. In VS Code, you can usually start a comment with `/**` and press `Enter` to let the IDE automatically create some starter text for you.
+
+### Tips
+
+* Read the functional requirements carefully, and take special care to identify *objects*, their *data*, and their *actions*.
+* It is highly recommended that you write your tests firsts, and then build what you need to make the tests work. This is essential to [Test-Driven Development][tdd-article].
+* How will you ensure that books are properly checked out using the library? What if someone tries to check out a book the library doesn't own (or vice-versa with returns)?
+* What are the public methods that you need to have to get the system working? Don't make anything public that you don't need to fulfill the requirements of the assignment. For instance, adding a getter method for a book's ISBN makes sense, but adding a method for returning the library's hours of operation is beyond the scope of this assignment.
+* How can you use collections to manage books and patrons? For instance, it would be wise to ensure that patrons can only be registered once based on some unique identifier.
+
+[tdd-article]: https://semaphoreci.com/blog/test-driven-development
diff --git a/lesson_17/oop/.gitattributes b/lesson_17/oop/.gitattributes
new file mode 100644
index 000000000..097f9f98d
--- /dev/null
+++ b/lesson_17/oop/.gitattributes
@@ -0,0 +1,9 @@
+#
+# https://help.github.com/articles/dealing-with-line-endings/
+#
+# Linux start script should use lf
+/gradlew        text eol=lf
+
+# These are Windows script files and should use crlf
+*.bat           text eol=crlf
+
diff --git a/lesson_17/oop/.gitignore b/lesson_17/oop/.gitignore
new file mode 100644
index 000000000..1b6985c00
--- /dev/null
+++ b/lesson_17/oop/.gitignore
@@ -0,0 +1,5 @@
+# Ignore Gradle project-specific cache directory
+.gradle
+
+# Ignore Gradle build output directory
+build
diff --git a/lesson_17/oop/gradle/wrapper/gradle-wrapper.jar b/lesson_17/oop/gradle/wrapper/gradle-wrapper.jar
new file mode 100644
index 000000000..ccebba771
Binary files /dev/null and b/lesson_17/oop/gradle/wrapper/gradle-wrapper.jar differ
diff --git a/lesson_17/oop/gradle/wrapper/gradle-wrapper.properties b/lesson_17/oop/gradle/wrapper/gradle-wrapper.properties
new file mode 100644
index 000000000..bdc9a83b1
--- /dev/null
+++ b/lesson_17/oop/gradle/wrapper/gradle-wrapper.properties
@@ -0,0 +1,6 @@
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-8.0.2-bin.zip
+networkTimeout=10000
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists
diff --git a/lesson_17/oop/gradlew b/lesson_17/oop/gradlew
new file mode 100755
index 000000000..79a61d421
--- /dev/null
+++ b/lesson_17/oop/gradlew
@@ -0,0 +1,244 @@
+#!/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/HEAD/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
+
+# This is normally unused
+# shellcheck disable=SC2034
+APP_BASE_NAME=${0##*/}
+APP_HOME=$( cd "${APP_HOME:-./}" && pwd -P ) || exit
+
+# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"'
+
+# Use the maximum available, or set MAX_FD != -1 to use that value.
+MAX_FD=maximum
+
+warn () {
+    echo "$*"
+} >&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 $MAX_FD in #(
+      max*)
+        # In POSIX sh, ulimit -H is undefined. That's why the result is checked to see if it worked.
+        # shellcheck disable=SC3045
+        MAX_FD=$( ulimit -H -n ) ||
+            warn "Could not query maximum file descriptor limit"
+    esac
+    case $MAX_FD in  #(
+      '' | soft) :;; #(
+      *)
+        # In POSIX sh, ulimit -n is undefined. That's why the result is checked to see if it worked.
+        # shellcheck disable=SC3045
+        ulimit -n "$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 "$CLASSPATH" \
+        org.gradle.wrapper.GradleWrapperMain \
+        "$@"
+
+# Stop when "xargs" is not available.
+if ! command -v xargs >/dev/null 2>&1
+then
+    die "xargs is not available"
+fi
+
+# 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 "$JAVACMD" "$@"
diff --git a/lesson_17/oop/gradlew.bat b/lesson_17/oop/gradlew.bat
new file mode 100644
index 000000000..93e3f59f1
--- /dev/null
+++ b/lesson_17/oop/gradlew.bat
@@ -0,0 +1,92 @@
+@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=.
+@rem This is normally unused
+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% equ 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% equ 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!
+set EXIT_CODE=%ERRORLEVEL%
+if %EXIT_CODE% equ 0 set EXIT_CODE=1
+if not ""=="%GRADLE_EXIT_CONSOLE%" exit %EXIT_CODE%
+exit /b %EXIT_CODE%
+
+:mainEnd
+if "%OS%"=="Windows_NT" endlocal
+
+:omega
diff --git a/lesson_17/oop/oop_app/build.gradle.kts b/lesson_17/oop/oop_app/build.gradle.kts
new file mode 100644
index 000000000..ab18680b7
--- /dev/null
+++ b/lesson_17/oop/oop_app/build.gradle.kts
@@ -0,0 +1,64 @@
+plugins {
+    // Apply the application plugin to add support for building a CLI application in Java.
+    application
+    eclipse
+    id("com.diffplug.spotless") version "6.25.0"
+	  id("org.springframework.boot") version "3.2.2"
+    id("com.adarshr.test-logger") version "4.0.0"
+}
+
+apply(plugin = "io.spring.dependency-management")
+
+repositories {
+    // Use Maven Central for resolving dependencies.
+    mavenCentral()
+}
+
+dependencies {
+    // Use JUnit Jupiter for testing.
+    testImplementation("com.codedifferently.instructional:instructional-lib")
+    testImplementation("org.junit.jupiter:junit-jupiter:5.9.1")
+    testImplementation("org.springframework.boot:spring-boot-starter-test")
+    testImplementation("org.assertj:assertj-core:3.25.1")
+    testImplementation("at.favre.lib:bcrypt:0.10.2")
+
+    // This dependency is used by the application.
+    implementation("com.codedifferently.instructional:instructional-lib")
+    implementation("com.google.guava:guava:31.1-jre")
+    implementation("com.google.code.gson:gson:2.10.1")
+    implementation("org.projectlombok:lombok:1.18.30")
+    implementation("org.springframework.boot:spring-boot-starter")
+}
+
+application {
+    // Define the main class for the application.
+    mainClass.set("com.codedifferently.lesson17.Lesson17")
+}
+
+tasks.named<Test>("test") {
+    // Use JUnit Platform for unit tests.
+    useJUnitPlatform()
+}
+
+
+configure<com.diffplug.gradle.spotless.SpotlessExtension> {
+
+  format("misc", {
+    // define the files to apply `misc` to
+    target("*.gradle", ".gitattributes", ".gitignore")
+
+    // define the steps to apply to those files
+    trimTrailingWhitespace()
+    indentWithTabs() // or spaces. Takes an integer argument if you don't like 4
+    endWithNewline()
+  })
+
+  java {
+    // don't need to set target, it is inferred from java
+
+    // apply a specific flavor of google-java-format
+    googleJavaFormat()
+    // fix formatting of type annotations
+    formatAnnotations()
+  }
+}
diff --git a/lesson_17/oop/oop_app/src/main/java/com/codedifferently/lesson17/Lesson17.java b/lesson_17/oop/oop_app/src/main/java/com/codedifferently/lesson17/Lesson17.java
new file mode 100644
index 000000000..c11084e57
--- /dev/null
+++ b/lesson_17/oop/oop_app/src/main/java/com/codedifferently/lesson17/Lesson17.java
@@ -0,0 +1,15 @@
+package com.codedifferently.lesson17;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.context.annotation.Configuration;
+
+@Configuration
+@SpringBootApplication(scanBasePackages = "com.codedifferently")
+public class Lesson17 {
+
+  public static void main(String[] args) {
+    var application = new SpringApplication(Lesson17.class);
+    application.run(args);
+  }
+}
diff --git a/lesson_17/oop/oop_app/src/main/java/com/codedifferently/lesson17/library/Book.java b/lesson_17/oop/oop_app/src/main/java/com/codedifferently/lesson17/library/Book.java
new file mode 100644
index 000000000..2e4d93037
--- /dev/null
+++ b/lesson_17/oop/oop_app/src/main/java/com/codedifferently/lesson17/library/Book.java
@@ -0,0 +1,60 @@
+package com.codedifferently.lesson17.library;
+
+import java.util.List;
+
+/** Represents a book in the library. */
+public class Book {
+  private String title;
+  private String isbn;
+  private List<String> authors;
+  private int numPages;
+  private boolean checkedOut;
+
+  public Book(String title, String isbn, List<String> authors, int numPages) {
+    this.title = title;
+    this.isbn = isbn;
+    this.authors = authors;
+    this.numPages = numPages;
+    this.checkedOut = false;
+  }
+
+  public String getTitle() {
+    return title;
+  }
+
+  public void setTitle(String title) {
+    this.title = title;
+  }
+
+  public String getIsbn() {
+    return isbn;
+  }
+
+  public void setIsbn(String isbn) {
+    this.isbn = isbn;
+  }
+
+  public List<String> getAuthors() {
+    return authors;
+  }
+
+  public void setAuthors(List<String> authors) {
+    this.authors = authors;
+  }
+
+  public int getNumPages() {
+    return numPages;
+  }
+
+  public void setNumPages(int numPages) {
+    this.numPages = numPages;
+  }
+
+  public boolean isCheckedOut() {
+    return checkedOut;
+  }
+
+  public void setCheckedOut(boolean checkedOut) {
+    this.checkedOut = checkedOut;
+  }
+}
diff --git a/lesson_17/oop/oop_app/src/main/java/com/codedifferently/lesson17/library/Library.java b/lesson_17/oop/oop_app/src/main/java/com/codedifferently/lesson17/library/Library.java
new file mode 100644
index 000000000..8f56dbd2f
--- /dev/null
+++ b/lesson_17/oop/oop_app/src/main/java/com/codedifferently/lesson17/library/Library.java
@@ -0,0 +1,59 @@
+package com.codedifferently.lesson17.library;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/** Represents a library with books and patrons. */
+public class Library {
+  private List<Book> marvelComics;
+  private List<Patron> patrons;
+
+  public Library() {
+    this.marvelComics = new ArrayList<>();
+    this.patrons = new ArrayList<>();
+  }
+
+  public void addComic(Book comic) {
+    marvelComics.add(comic);
+  }
+
+  public void removeComic(Book comic) {
+    marvelComics.remove(comic);
+  }
+
+  public void registerPatron(Patron patron) {
+    patrons.add(patron);
+  }
+
+  public void checkOutComic(Book comic, Patron patron) {
+    if (marvelComics.contains(comic) && patrons.contains(patron)) {
+      patron.checkOutBook(comic);
+    } else {
+      System.out.println("Marvel comic or patron not found in the library.");
+    }
+  }
+
+  public void returnComic(Book comic, Patron patron) {
+    if (marvelComics.contains(comic) && patrons.contains(patron)) {
+      patron.returnBook(comic);
+    } else {
+      System.out.println("Marvel comic or patron not found in the library.");
+    }
+  }
+
+  public List<Book> getMarvelComics() {
+    return marvelComics;
+  }
+
+  public void setMarvelComics(List<Book> marvelComics) {
+    this.marvelComics = marvelComics;
+  }
+
+  public List<Patron> getPatrons() {
+    return patrons;
+  }
+
+  public void setPatrons(List<Patron> patrons) {
+    this.patrons = patrons;
+  }
+}
diff --git a/lesson_17/oop/oop_app/src/main/java/com/codedifferently/lesson17/library/Patron.java b/lesson_17/oop/oop_app/src/main/java/com/codedifferently/lesson17/library/Patron.java
new file mode 100644
index 000000000..427a02f6a
--- /dev/null
+++ b/lesson_17/oop/oop_app/src/main/java/com/codedifferently/lesson17/library/Patron.java
@@ -0,0 +1,49 @@
+package com.codedifferently.lesson17.library;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/** Represents a patron of the library. */
+public class Patron {
+  private String name;
+  private List<Book> checkedOutBooks;
+
+  public Patron(String name) {
+    this.name = name;
+    this.checkedOutBooks = new ArrayList<>();
+  }
+
+  public String getName() {
+    return name;
+  }
+
+  public void setName(String name) {
+    this.name = name;
+  }
+
+  public List<Book> getCheckedOutBooks() {
+    return checkedOutBooks;
+  }
+
+  public void setCheckedOutBooks(List<Book> checkedOutBooks) {
+    this.checkedOutBooks = checkedOutBooks;
+  }
+
+  public void checkOutBook(Book book) {
+    if (!book.isCheckedOut()) {
+      book.setCheckedOut(true);
+      checkedOutBooks.add(book);
+    } else {
+      System.out.println("Marvel comic is already checked out.");
+    }
+  }
+
+  public void returnBook(Book book) {
+    if (checkedOutBooks.contains(book)) {
+      book.setCheckedOut(false);
+      checkedOutBooks.remove(book);
+    } else {
+      System.out.println("Marvel comic is not checked out by this patron.");
+    }
+  }
+}
diff --git a/lesson_17/oop/oop_app/src/test/java/com/codedifferently/lesson17/Lesson17Test.java b/lesson_17/oop/oop_app/src/test/java/com/codedifferently/lesson17/Lesson17Test.java
new file mode 100644
index 000000000..9f1e93bb0
--- /dev/null
+++ b/lesson_17/oop/oop_app/src/test/java/com/codedifferently/lesson17/Lesson17Test.java
@@ -0,0 +1,13 @@
+package com.codedifferently.lesson17;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import org.junit.jupiter.api.Test;
+
+class Lesson17Test {
+
+  @Test
+  void testLesson17_create() {
+    assertThat(new Lesson17()).isNotNull();
+  }
+}
diff --git a/lesson_17/oop/settings.gradle.kts b/lesson_17/oop/settings.gradle.kts
new file mode 100644
index 000000000..e5004de63
--- /dev/null
+++ b/lesson_17/oop/settings.gradle.kts
@@ -0,0 +1,13 @@
+/*
+ * 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/8.0.2/userguide/multi_project_builds.html
+ */
+
+includeBuild("../../lib/java/codedifferently-instructional")
+
+rootProject.name = "lesson_17"
+include("oop_app")