Add JSpecify to spring-shell-core

Signed-off-by: Piotr Olaszewski <[email protected]>

Author: piotrooo

spring-shell-core/pom.xml

@@ -61,6 +61,11 @@
 			<artifactId>jakarta.validation-api</artifactId>
 			<version>${jakarta.validation-api.version}</version>
 		</dependency>
+		<dependency>
+			<groupId>org.jspecify</groupId>
+			<artifactId>jspecify</artifactId>
+			<version>${jspecify.version}</version>
+		</dependency>
 
 		<!-- Test dependencies -->
 		<dependency>

spring-shell-core/src/main/java/org/springframework/shell/Availability.java

@@ -16,19 +16,21 @@
 
 package org.springframework.shell;
 
+import org.jspecify.annotations.Nullable;
 import org.springframework.util.Assert;
 
 /**
  * Indicates whether or not a command is currently available. When not available, provides
  * a reason.
  *
  * @author Eric Bottard
+ * @author Piotr Olaszewski
  */
 public class Availability {
 
-    private final String reason;
+    private final @Nullable String reason;
 
-    private Availability(String reason) {
+    private Availability(@Nullable String reason) {
         this.reason = reason;
     }
 
@@ -45,7 +47,7 @@ public boolean isAvailable() {
         return reason == null;
     }
 
-    public String getReason() {
+    public @Nullable String getReason() {
         return reason;
     }
 }

spring-shell-core/src/main/java/org/springframework/shell/Command.java

@@ -18,9 +18,13 @@
 
 import java.util.Objects;
 
+import org.jspecify.annotations.Nullable;
 import org.springframework.util.Assert;
 import org.springframework.util.StringUtils;
 
+/**
+ * @author Piotr Olaszewski
+ */
 public interface Command {
 
 	/**
@@ -45,10 +49,10 @@ public Help(String description) {
 			this(description, null);
 		}
 
-		public Help(String description, String group) {
-			this.group = StringUtils.hasText(group) ? group : "";
-			Assert.isTrue(StringUtils.hasText(description), "Command description cannot be null or empty in group='" + this.group + "'");
+		public Help(String description, @Nullable String group) {
+			Assert.isTrue(StringUtils.hasText(description), "Command description cannot be null or empty");
 			this.description = description;
+			this.group = StringUtils.hasText(group) ? group : "";
 		}
 
 		public String getDescription() {

spring-shell-core/src/main/java/org/springframework/shell/CommandNotFound.java

@@ -20,22 +20,25 @@
 import java.util.Map;
 import java.util.stream.Collectors;
 
+import org.jspecify.annotations.Nullable;
 import org.springframework.shell.command.CommandRegistration;
 
 /**
  * A result to be handled by the {@link ResultHandler} when no command could be mapped to user input
+ *
+ * @author Piotr Olaszewski
  */
 public class CommandNotFound extends RuntimeException {
 
 	private final List<String> words;
-	private final Map<String, CommandRegistration> registrations;
-	private final String text;
+	private final @Nullable Map<String, CommandRegistration> registrations;
+	private final @Nullable String text;
 
 	public CommandNotFound(List<String> words) {
 		this(words, null, null);
 	}
 
-	public CommandNotFound(List<String> words, Map<String, CommandRegistration> registrations, String text) {
+	public CommandNotFound(List<String> words, @Nullable Map<String, CommandRegistration> registrations, @Nullable String text) {
 		this.words = words;
 		this.registrations = registrations;
 		this.text = text;
@@ -60,7 +63,7 @@ public List<String> getWords(){
 	 *
 	 * @return known command registrations
 	 */
-	public Map<String, CommandRegistration> getRegistrations() {
+	public @Nullable Map<String, CommandRegistration> getRegistrations() {
 		return registrations;
 	}
 
@@ -69,7 +72,7 @@ public Map<String, CommandRegistration> getRegistrations() {
 	 *
 	 * @return raw text input
 	 */
-	public String getText() {
+	public @Nullable String getText() {
 		return text;
 	}
 }

spring-shell-core/src/main/java/org/springframework/shell/CompletingParsedLine.java

@@ -24,9 +24,10 @@
  * should be escaped/quoted.
  *
  * @author Eric Bottard
+ * @author Piotr Olaszewski
  */
 @FunctionalInterface
 public interface CompletingParsedLine {
 
-	public CharSequence emit(CharSequence candidate);
+	CharSequence emit(CharSequence candidate);
 }

spring-shell-core/src/main/java/org/springframework/shell/CompletionContext.java

@@ -16,17 +16,19 @@
 
 package org.springframework.shell;
 
+import org.jspecify.annotations.Nullable;
+import org.springframework.shell.command.CommandOption;
+import org.springframework.shell.command.CommandRegistration;
+
 import java.util.ArrayList;
 import java.util.List;
 import java.util.stream.Collectors;
 
-import org.springframework.shell.command.CommandOption;
-import org.springframework.shell.command.CommandRegistration;
-
 /**
  * Represents the buffer context in which completion was triggered.
  *
  * @author Eric Bottard
+ * @author Piotr Olaszewski
  */
 public class CompletionContext {
 
@@ -36,17 +38,17 @@ public class CompletionContext {
 
 	private final int position;
 
-	private final CommandOption commandOption;
+	private final @Nullable CommandOption commandOption;
 
-	private final CommandRegistration commandRegistration;
+	private final @Nullable CommandRegistration commandRegistration;
 
 	/**
 	 *
-	 * @param words words in the buffer, excluding words for the command name
+	 * @param words     words in the buffer, excluding words for the command name
 	 * @param wordIndex the index of the word the cursor is in
-	 * @param position the position inside the current word where the cursor is
+	 * @param position  the position inside the current word where the cursor is
 	 */
-	public CompletionContext(List<String> words, int wordIndex, int position, CommandRegistration commandRegistration,  CommandOption commandOption) {
+	public CompletionContext(List<String> words, int wordIndex, int position, @Nullable CommandRegistration commandRegistration, @Nullable CommandOption commandOption) {
 		this.words = words;
 		this.wordIndex = wordIndex;
 		this.position = position;
@@ -66,11 +68,11 @@ public int getPosition() {
 		return position;
 	}
 
-	public CommandOption getCommandOption() {
+	public @Nullable CommandOption getCommandOption() {
 		return commandOption;
 	}
 
-	public CommandRegistration getCommandRegistration() {
+	public @Nullable CommandRegistration getCommandRegistration() {
 		return commandRegistration;
 	}
 
@@ -80,19 +82,22 @@ public String upToCursor() {
 			if (!start.isEmpty()) {
 				start += " ";
 			}
-			start += currentWord().substring(0, position);
+			String currentWord = currentWord();
+			if (currentWord != null) {
+				start += currentWord.substring(0, position);
+			}
 		}
 		return start;
 	}
 
 	/**
 	 * Return the whole word the cursor is in, or {@code null} if the cursor is past the last word.
 	 */
-	public String currentWord() {
+	public @Nullable String currentWord() {
 		return wordIndex >= 0 && wordIndex < words.size() ? words.get(wordIndex) : null;
 	}
 
-	public String currentWordUpToCursor() {
+	public @Nullable String currentWordUpToCursor() {
 		String currentWord = currentWord();
 		return currentWord != null ? currentWord.substring(0, getPosition()) : null;
 	}
@@ -101,7 +106,7 @@ public String currentWordUpToCursor() {
 	 * Return a copy of this context, as if the first {@literal nbWords} were not present
 	 */
 	public CompletionContext drop(int nbWords) {
-		return new CompletionContext(new ArrayList<String>(words.subList(nbWords, words.size())), wordIndex - nbWords,
+		return new CompletionContext(new ArrayList<>(words.subList(nbWords, words.size())), wordIndex - nbWords,
 				position, commandRegistration, commandOption);
 	}
 
@@ -115,7 +120,7 @@ public CompletionContext commandOption(CommandOption commandOption) {
 	/**
 	 * Return a copy of this context with given command registration.
 	 */
-	public CompletionContext commandRegistration(CommandRegistration commandRegistration) {
+	public CompletionContext commandRegistration(@Nullable CommandRegistration commandRegistration) {
 		return new CompletionContext(words, wordIndex, position, commandRegistration, commandOption);
 	}
 }

spring-shell-core/src/main/java/org/springframework/shell/CompletionProposal.java

@@ -16,12 +16,15 @@
 
 package org.springframework.shell;
 
+import org.jspecify.annotations.Nullable;
+
 import java.util.Objects;
 
 /**
  * Represents a proposal for TAB completion, made not only of the text to append, but also metadata about the proposal.
  *
  * @author Eric Bottard
+ * @author Piotr Olaszewski
  */
 public class CompletionProposal {
 
@@ -38,12 +41,12 @@ public class CompletionProposal {
 	/**
 	 * The description for the proposal.
 	 */
-	private String description;
+	private @Nullable String description;
 
 	/**
 	 * The category of the proposal, which may be used to group proposals together.
 	 */
-	private String category;
+	private @Nullable String category;
 
 	/**
 	 * Whether the proposal should bypass escaping and quoting rules. This is useful for command proposals, which can
@@ -79,16 +82,16 @@ public CompletionProposal displayText(String displayText) {
 		return this;
 	}
 
-	public String description() {
+	public @Nullable String description() {
 		return description;
 	}
 
-	public CompletionProposal description(String description) {
+	public CompletionProposal description(@Nullable String description) {
 		this.description = description;
 		return this;
 	}
 
-	public String category() {
+	public @Nullable String category() {
 		return category;
 	}
 

spring-shell-core/src/main/java/org/springframework/shell/CoreResourcesRuntimeHints.java

@@ -15,18 +15,20 @@
  */
 package org.springframework.shell;
 
+import org.jspecify.annotations.Nullable;
 import org.springframework.aot.hint.RuntimeHints;
 import org.springframework.aot.hint.RuntimeHintsRegistrar;
 
 /**
  * {@link RuntimeHintsRegistrar} for Shell Core resources.
  *
  * @author Janne Valkealahti
+ * @author Piotr Olaszewski
  */
 class CoreResourcesRuntimeHints implements RuntimeHintsRegistrar {
 
 	@Override
-	public void registerHints(RuntimeHints hints, ClassLoader classLoader) {
+	public void registerHints(RuntimeHints hints, @Nullable ClassLoader classLoader) {
 		hints.resources().registerPattern("org/springframework/shell/component/*.stg");
 	}
 }

spring-shell-core/src/main/java/org/springframework/shell/DefaultShellApplicationRunner.java

@@ -1,9 +1,12 @@
 package org.springframework.shell;
 
+import org.jspecify.annotations.Nullable;
+
 /**
  * To be implemented by components able to provide a "line" of user input, whether interactively or by batch.
  *
  * @author Eric Bottard
+ * @author Piotr Olaszewski
  */
 public interface InputProvider {
 
@@ -12,5 +15,5 @@ public interface InputProvider {
 	 *
 	 * <p>Returning {@literal null} indicates end of input, requesting shell exit.</p>
 	 */
-	Input readInput();
+	@Nullable Input readInput();
 }