Add lab content.

Author: ammbra

.idea/.gitignore

@@ -0,0 +1,13 @@
+{
+    "java.project.sourcePaths": [
+        "A_bday_java/src/main/java",
+        "B_bday_javadoc/src/main/java",
+        "C_bday_jwebserver/src/main/java",
+        "D_bday_jlink/src/main/java",
+        "E_bday_jfr/src/main/java",
+    ],
+    "java.project.referencedLibraries": [
+        "lib/**/*.jar"
+    ],
+    "java.project.outputPath": "out"
+}

.idea/misc.xml

@@ -0,0 +1,30 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<module type="JAVA_MODULE" version="4">
+  <component name="NewModuleRootManager" inherit-compiler-output="true">
+    <exclude-output />
+    <content url="file://$MODULE_DIR$">
+      <sourceFolder url="file://$MODULE_DIR$/src/main/java" isTestSource="false" />
+      <sourceFolder url="file://$MODULE_DIR$/src/test/java" isTestSource="true" />
+      <sourceFolder url="file://$MODULE_DIR$/src/main/resources" type="java-resource" />
+    </content>
+    <orderEntry type="inheritedJdk" />
+    <orderEntry type="sourceFolder" forTests="false" />
+    <orderEntry type="library" name="lib" level="project" />
+    <orderEntry type="module-library" scope="TEST">
+      <library name="JUnit5.8.1">
+        <CLASSES>
+          <root url="jar://$MODULE_DIR$/../lib/junit-jupiter-5.8.1.jar!/" />
+          <root url="jar://$MODULE_DIR$/../lib/junit-jupiter-api-5.8.1.jar!/" />
+          <root url="jar://$MODULE_DIR$/../lib/opentest4j-1.2.0.jar!/" />
+          <root url="jar://$MODULE_DIR$/../lib/junit-platform-commons-1.8.1.jar!/" />
+          <root url="jar://$MODULE_DIR$/../lib/apiguardian-api-1.1.2.jar!/" />
+          <root url="jar://$MODULE_DIR$/../lib/junit-jupiter-params-5.8.1.jar!/" />
+          <root url="jar://$MODULE_DIR$/../lib/junit-jupiter-engine-5.8.1.jar!/" />
+          <root url="jar://$MODULE_DIR$/../lib/junit-platform-engine-1.8.1.jar!/" />
+        </CLASSES>
+        <JAVADOC />
+        <SOURCES />
+      </library>
+    </orderEntry>
+  </component>
+</module>

.idea/modules.xml

@@ -0,0 +1,56 @@
+# Working with the Java Launcher
+
+## Project Structure
+
+Here's a breakdown of the different project components:
+
+* `src/main/java`: The source code for the project, organized by package:
+    * `eu.ammbra.bday.Organizer.java`: The main entry point of the application, possibly responsible for coordinating the overall flow of the program.
+    * `eu.ammbra.bday.details`: A package containing domain model classes. These classes represent entities involved in birthday celebrations, such as cakes, parties, and people attending them.
+    * `eu.ammbra.bday.handlers`: A package containing classes responsible for handling specific tasks. 
+    * `eu.ammbra.bday.operations`: A package containing classes responsible for handling the operational side of parties.
+    * `eu.ammbra.bday.store`: A package containing classes responsible for interacting with data from files.
+* `src/main/resources/store/events.json`: A resource file containing sample event data in JSON format.
+* `src/test/java`: The source code for unit tests and integration tests.
+
+## **Lab Activity No 1**:  Launch Multiple Java Files
+
+Since JDK 22 you can use the Java launcher to [execute source-code programs provided as multiple files](https://docs.oracle.com/en/java/javase/23/docs/specs/man/java.html#using-source-file-mode-to-launch-source-code-programs).
+
+```shell
+java --class-path '*' Prog1.java
+```
+This activity relies on you to execute the following steps:
+
+1. Open a terminal window in the `lab-jdk-tools/A_bday_java` folder. You can use the terminal of your IDE/code editor.
+2. Check that $JAVA_HOME is properly set by trying `echo $JAVA_HOME`.
+3. Inside the terminal, execute the `java` command to launch `Organizer` class from `src/main/java/eu/ammbra/bday/`.
+Pay attention to the following:
+
+* classpath libraries located in `lab-jdk-tools/lib` folder.
+* the project uses preview features so do not forget to enable those via `--enable-preview`
+
+## Solution
+
+→ [Click to see the solution](SOLUTION.md#lab-activity-no-1-launch-multiple-java-files)
+
+## **Lab Activity No 2**: Use the Java Command-Line Argument Files
+
+When working with the `java` launcher, you can shorten or simplify the `java` command by using `@` argument files to specify one or more text files that contain arguments.
+The arguments can be options and class names, which are then passed to the `java` command. [This](https://docs.oracle.com/en/java/javase/23/docs/specs/man/java.html#java-command-line-argument-files) allows you to :
+
+* create `java` commands of any length on any operating system
+* for containerized applications, easily swap the content the argument files without modifying the Dockerfile.
+
+This activity requires you to:
+
+1. Create a file and copy the arguments you used to launch the `Organizer` class from `src/main/java/eu/ammbra/bday/`.
+2. Now launch again the `Organizer` class by providing the file as argument `java @your-arg-file-name`.
+
+## Solution
+
+→ [Click to see the solution](SOLUTION.md#lab-activity-no-2-use-the-java-command-line-argument-files)
+
+Next step is to [create some documentation](../B_bday_javadoc/README.md)!
+
+

.idea/vcs.xml

@@ -0,0 +1,35 @@
+# Solutions for Working with the Java Launcher
+
+## **Lab Activity No 1**: Launch Multiple Java Files
+
+<details>
+<summary>Click to expand</summary>
+
+```shell
+
+# Unix and macOS compatible command
+
+java --enable-preview -cp "../lib/*" src/main/java/eu/ammbra/bday/Organizer.java
+
+# Windows compatible command
+
+java --enable-preview -cp "..\lib\*" src\main\java\eu\ammbra\bday\Organizer.java
+
+```
+
+</details>
+
+## **Lab Activity No 2**: Use the Java Command-Line Argument Files
+
+<details>
+<summary>Click to expand</summary>
+
+```shell
+# make sure you copied `--enable-preview -cp "../lib/*" src/main/java/eu/ammbra/bday/Organizer.java`
+java @my-arg-file
+
+```
+
+</details>
+
+[Let's go and create some documentation](../B_bday_javadoc/README.md)!

.vscode/settings.json

@@ -0,0 +1,33 @@
+package eu.ammbra.bday;
+
+import com.sun.net.httpserver.HttpServer;
+import eu.ammbra.bday.handlers.PartyHandler;
+import eu.ammbra.bday.store.DataStore;
+import eu.ammbra.bday.operations.PartyService;
+
+import java.io.IOException;
+import java.net.InetSocketAddress;
+
+
+/// Main server application for an application responsible for organizing a birthday party.
+/// This server serves both static files and dynamic API endpoints.
+///
+public class Organizer {
+	private static final int PORT = 8081;
+
+
+	/// Starts the HTTP server to serve static files and dynamic store.
+	///
+	/// @param args Command-line arguments that may contain the path to static JSON file.
+	/// @throws IOException If the server cannot start.
+	///
+	public static void main(String[] args) throws IOException {
+		String filename = (args.length > 0) ? args[0] : "./src/main/resources/store/events.json";
+		DataStore store  = new DataStore(filename);
+		PartyService service = new PartyService(store);
+		HttpServer server = HttpServer.create(new InetSocketAddress(PORT), 0);
+		server.createContext("/api/organize", new PartyHandler(service));
+		System.out.printf("Birthday Party Server is running at http://127.0.0.1:%d/api/organize%n", PORT);
+		server.start();
+	}
+}

A_bday_java/A_bday_java.iml

@@ -0,0 +1,4 @@
+package eu.ammbra.bday.details;
+
+public record Cake(String flavor, int layers, double weight) {
+}

A_bday_java/README.md

@@ -0,0 +1,3 @@
+package eu.ammbra.bday.details;
+
+public record Celebration(long id, Person person, String flavor, String location, int attendees) {}

A_bday_java/SOLUTION.md

@@ -0,0 +1,4 @@
+package eu.ammbra.bday.details;
+
+public record Party(long id, String name, Cake cake, String location, int attendees) {
+}

A_bday_java/src/main/java/eu/ammbra/bday/Organizer.java

@@ -0,0 +1,6 @@
+package eu.ammbra.bday.details;
+
+import java.time.LocalDate;
+
+public record Person(String firstName, String lastName, LocalDate date) {
+}

A_bday_java/src/main/java/eu/ammbra/bday/details/Cake.java

@@ -0,0 +1,44 @@
+package eu.ammbra.bday.handlers;
+
+import com.google.gson.*;
+
+import java.lang.reflect.Type;
+import java.time.LocalDate;
+import java.time.format.DateTimeFormatter;
+
+ /// Custom adapter for serializing and deserializing {@link LocalDate} objects to/from JSON strings.
+ ///
+ /// This adapter uses the ISO date format `yyyy-MM-dd` for serialization and deserialization.
+ ///
+public class LocalDateTypeAdapter implements JsonSerializer<LocalDate>, JsonDeserializer<LocalDate> {
+
+	 /// Formatter used for parsing and formatting dates.
+	private final DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyy-MM-dd");
+
+	 /// Serializes a {@link LocalDate} object to a JSON string.
+	 ///
+	 /// @param date       the date to serialize
+	 /// @param srcType    the type of the source object
+	 /// @param context    the serialization context
+	 /// @return a JSON primitive representing the serialized date
+	 ///
+	@Override
+	public JsonElement serialize(final LocalDate date, final Type srcType,
+								 final JsonSerializationContext context) {
+		return new JsonPrimitive(date.format(formatter));
+	}
+
+	 /// Deserializes a JSON string to a {@link LocalDate} object.
+	 ///
+	 /// @param json      the JSON element to deserialize
+	 /// @param targetType   the type of the target object
+	 /// @param context   the deserialization context
+	 /// @return the deserialized date
+	 /// @throws JsonParseException if the JSON element cannot be parsed
+	 ///
+	 @Override
+	public LocalDate deserialize(final JsonElement json, final Type targetType,
+								 final JsonDeserializationContext context) throws JsonParseException {
+		return LocalDate.parse(json.getAsString(), formatter);
+	}
+}

A_bday_java/src/main/java/eu/ammbra/bday/details/Celebration.java

@@ -0,0 +1,77 @@
+package eu.ammbra.bday.handlers;
+
+import com.google.gson.Gson;
+import com.sun.net.httpserver.HttpHandler;
+import com.sun.net.httpserver.HttpExchange;
+import eu.ammbra.bday.details.Party;
+import eu.ammbra.bday.operations.PartyNotFoundException;
+import eu.ammbra.bday.operations.PartyService;
+
+import java.io.IOException;
+import java.io.OutputStream;
+import java.nio.charset.StandardCharsets;
+import java.util.List;
+
+
+///Handles HTTP requests for party-related store.
+///
+public class PartyHandler implements HttpHandler {
+
+	private final PartyService service;
+
+
+	///Constructs a new PartyHandler instance with the specified service.
+	///
+	///@param service the party service instance
+	///
+	public PartyHandler(PartyService service) {
+		this.service = service;
+	}
+
+
+	///Handles an HTTP request for party-related store.
+	///
+	/// @param exchange the HTTP exchange object
+	 /// @throws IOException if an I/O error occurs
+	///
+	@Override
+	public void handle(HttpExchange exchange) throws IOException {
+		if ("GET".equalsIgnoreCase(exchange.getRequestMethod())) {
+			StringBuilder result = new StringBuilder();
+			int statusCode = 200;
+
+			String path = exchange.getRequestURI().getPath();
+
+			String[] segments = path.split("/");
+
+			switch (segments.length) {
+				case int _ when (segments.length < 3 || !segments[2].equals("organize")) -> {
+					result.append("Invalid endpoint");
+					statusCode = 404;
+				}
+				case 3 -> {
+					List<Party> parties = service.processAllParties();
+					result.append(new Gson().toJson(parties));
+				}
+				case int _ -> {
+					try {
+						Party party = service.processPartyById(Long.parseLong(segments[3]));
+						result.append(new Gson().toJson(party));
+					} catch (PartyNotFoundException e) {
+						result.append(e.getMessage());
+					}
+				}
+			}
+
+			exchange.getResponseHeaders().set("Content-Type", "application/json");
+			String response = result.toString();
+			exchange.sendResponseHeaders(statusCode, response.getBytes().length);
+
+			try (OutputStream os = exchange.getResponseBody()) {
+				os.write(response.getBytes(StandardCharsets.UTF_8));
+			}
+		} else {
+			exchange.sendResponseHeaders(405, -1);
+		}
+	}
+}