Update SectionConfiguration to use optionals

src/main/java/io/github/syst3ms/skriptparser/lang/entries/LiteralLoader.java

@@ -10,6 +10,7 @@
 import java.util.List;
 
 public class LiteralLoader<T> extends OptionLoader {
+
 	private final Class<T> typeClass;
 
 	public LiteralLoader(String key, Class<T> typeClass, boolean multiple, boolean optional) {
@@ -38,7 +39,13 @@ public boolean loadEntry(SectionConfiguration config, FileElement element, Parse
 		if (isMultiple()) {
 			List<T> data = new ArrayList<>();
 			boolean successful = true;
-			for (var value : config.getStringList(key)) {
+
+			var list = config.getStringList(key);
+			if (!list.isPresent()) {
+				logger.error("List at key '" + key + "' does not exist.", ErrorType.SEMANTIC_ERROR);
+				return false;
+			}
+			for (var value : list.get()) {
 				var result = parser.apply(value);
 				if (result == null) {
 					// With the logic that errors get skipped, we will allow the other values to be parsed.
@@ -52,7 +59,12 @@ public boolean loadEntry(SectionConfiguration config, FileElement element, Parse
 			config.getData().put(key, data.toArray());
 			return successful;
 		} else {
-			var result = parser.apply(config.getString(key));
+			var value = config.getString(key);
+			if (!value.isPresent()) {
+				logger.error("Key '" + key + "' does not exist.", ErrorType.SEMANTIC_ERROR);
+				return false;
+			}
+			var result = parser.apply(value.get());
 			// We don't want this data to linger if an error occurs
 			config.getData().remove(key);
 			if (result == null) {
@@ -62,5 +74,7 @@ public boolean loadEntry(SectionConfiguration config, FileElement element, Parse
 			config.getData().put(key, result);
 			return true;
 		}
+
 	}
+
 }

src/main/java/io/github/syst3ms/skriptparser/lang/entries/SectionConfiguration.java

@@ -12,6 +12,7 @@
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.Optional;
 
 /**
  * The SectionConfiguration class can be used to create simple and efficient data sections
@@ -34,12 +35,14 @@
  * </ul>
  */
 public class SectionConfiguration {
+
+	private final Map<String, Object> data = new HashMap<>();
+	private final List<EntryLoader> entries;
+
 	@Nullable
 	private CodeSection parent;
-	private final List<EntryLoader> entries;
-	private final Map<String, Object> data = new HashMap<>();
-	private boolean loaded = false;
-
+	private boolean loaded;
+
 	private SectionConfiguration(List<EntryLoader> entries) {
 		this.entries = entries;
 	}
@@ -49,6 +52,7 @@ private SectionConfiguration(List<EntryLoader> entries) {
 	 * a FileSection instance. This method should be called only once and will throw an error if attempting
 	 * to load the configuration multiple times. The default use-case would be to load the configuration inside
 	 * CodeSection's {@link CodeSection#loadSection(FileSection, ParserState, SkriptLogger) load} method.
+	 * 
 	 * @param parent the parent section
 	 * @param section the file section
 	 * @param parserState the parse state
@@ -64,9 +68,8 @@ public boolean loadConfiguration(@Nullable CodeSection parent, FileSection secti
 
 		outer:
 		for (var entry : entries) {
-			for (var el : section.getElements()) {
-				logger.setLine(el.getLine() - 1);
-
+			for (var element : section.getElements()) {
+				logger.setLine(element.getLine() - 1);
 				if (logger.hasError()) {
 					/*
 					 * If the execution of 'loadEntry' caused errors, it means that we
@@ -78,9 +81,9 @@ public boolean loadConfiguration(@Nullable CodeSection parent, FileSection secti
 					successful = false;
 					continue outer;
 				}
-				if (el instanceof VoidElement)
+				if (element instanceof VoidElement)
 					continue;
-				if (entry.loadEntry(this, el, parserState, logger))
+				if (entry.loadEntry(this, element, parserState, logger))
 					continue outer;
 			}
 			if (entry.isOptional())
@@ -115,6 +118,7 @@ public Map<String, Object> getData() {
 		return data;
 	}
 
+	@Nullable
 	public Object getValue(String key) {
 		return data.get(key);
 	}
@@ -124,32 +128,37 @@ public Object getValue(String key) {
 	 * This can only be used when you register your option as a {@link Builder#addLiteral(String, Class) literal},
 	 * otherwise, the option will likely be parsed as a String and throw an exception.
 	 * Options that allow literal lists are saved as an array.
-	 * @param key the key
-	 * @param cls the class to cast to
-	 * @return the value cast to the given class
-	 * @param <T> the type of the value
+	 * 
+	 * @param key the key of the node.
+	 * @param cls the class to cast to.
+	 * @return the value cast to the given class.
+	 * @param <T> the type of the return value.
 	 */
 	@SuppressWarnings("unchecked")
-	public <T> T getValue(String key, Class<T> cls) {
+	public <T> Optional<T> getValue(String key, Class<T> cls) {
 		var result = data.get(key);
+		if (result == null)
+			return Optional.empty();
 		if (result.getClass() == String.class && result.getClass() != cls)
 			throw new UnsupportedOperationException("The key '" + key + "' was not registered as a literal, was parsed as a String and can, therefore, not be cast to " + cls.getName());
-		return (T) result;
+		return Optional.of((T) result);
 	}
 
-	public String getString(String key) {
+	@Nullable
+	public Optional<String> getString(String key) {
 		return getValue(key, String.class);
 	}
 
-	public String[] getStringList(String key) {
+	public Optional<String[]> getStringList(String key) {
 		return getValue(key, String[].class);
 	}
 
-	public CodeSection getSection(String key) {
+	public Optional<CodeSection> getSection(String key) {
 		return getValue(key, CodeSection.class);
 	}
-	
+
 	public static class Builder {
+
 		private final List<EntryLoader> entries = new ArrayList<>();
 
 		public Builder addKey(String key) {
@@ -195,5 +204,7 @@ public Builder addLoader(EntryLoader loader) {
 		public SectionConfiguration build() {
 			return new SectionConfiguration(entries);
 		}
+
 	}
-}
+
+}