Fix handling of reflection target name in TypeReference

This commit adds a `getName` to `TypeReference` that provides a way to
generate the reflection target name of a type. This typically handle
primitives (omitting the `java.lang` packages) and arrays.

Closes gh-28347

Author: snicoll

spring-core/src/main/java/org/springframework/aot/generator/GeneratedTypeReference.java

@@ -32,14 +32,14 @@ public final class GeneratedTypeReference extends AbstractTypeReference {
 
 	private final ClassName className;
 
-	@Nullable
-	private final TypeReference enclosingType;
-
 	private GeneratedTypeReference(ClassName className) {
+		super(className.packageName(), className.simpleName(), safeCreate(className.enclosingClassName()));
 		this.className = className;
-		this.enclosingType = (className.enclosingClassName() != null
-				? new GeneratedTypeReference(className.enclosingClassName())
-				: null);
+	}
+
+	@Nullable
+	private static GeneratedTypeReference safeCreate(@Nullable ClassName className) {
+		return (className != null ? new GeneratedTypeReference(className) : null);
 	}
 
 	public static GeneratedTypeReference of(ClassName className) {
@@ -53,18 +53,8 @@ public String getCanonicalName() {
 	}
 
 	@Override
-	public String getPackageName() {
-		return this.className.packageName();
-	}
-
-	@Override
-	public String getSimpleName() {
-		return this.className.simpleName();
-	}
-
-	@Override
-	public TypeReference getEnclosingType() {
-		return this.enclosingType;
+	protected boolean isPrimitive() {
+		return this.className.isPrimitive();
 	}
 
 }

spring-core/src/main/java/org/springframework/aot/hint/AbstractTypeReference.java

@@ -18,6 +18,8 @@
 
 import java.util.Objects;
 
+import org.springframework.lang.Nullable;
+
 /**
  * Base {@link TypeReference} implementation that ensures consistent behaviour
  * for {@code equals()}, {@code hashCode()}, and {@code toString()} based on
@@ -28,6 +30,54 @@
  */
 public abstract class AbstractTypeReference implements TypeReference {
 
+	private final String packageName;
+
+	private final String simpleName;
+
+	@Nullable
+	private final TypeReference enclosingType;
+
+	protected AbstractTypeReference(String packageName, String simpleName, @Nullable TypeReference enclosingType) {
+		this.packageName = packageName;
+		this.simpleName = simpleName;
+		this.enclosingType = enclosingType;
+	}
+
+	@Override
+	public String getName() {
+		TypeReference enclosingType = getEnclosingType();
+		String simpleName = getSimpleName();
+		return (enclosingType != null
+				? (enclosingType.getName() + '$' + simpleName)
+				: addPackageIfNecessary(simpleName));
+	}
+
+	@Override
+	public String getPackageName() {
+		return this.packageName;
+	}
+
+	@Override
+	public String getSimpleName() {
+		return this.simpleName;
+	}
+
+	@Nullable
+	@Override
+	public TypeReference getEnclosingType() {
+		return this.enclosingType;
+	}
+
+	protected abstract boolean isPrimitive();
+
+	protected String addPackageIfNecessary(String part) {
+		if (this.packageName.isEmpty() ||
+				this.packageName.equals("java.lang") && isPrimitive()) {
+			return part;
+		}
+		return this.packageName + '.' + part;
+	}
+
 	@Override
 	public int hashCode() {
 		return Objects.hash(getCanonicalName());

spring-core/src/main/java/org/springframework/aot/hint/ReflectionTypeReference.java

@@ -27,14 +27,14 @@ final class ReflectionTypeReference extends AbstractTypeReference {
 
 	private final Class<?> type;
 
-	@Nullable
-	private final TypeReference enclosing;
-
-
 	private ReflectionTypeReference(Class<?> type) {
+		super(type.getPackageName(), type.getSimpleName(), safeCreate(type.getEnclosingClass()));
 		this.type = type;
-		this.enclosing = (type.getEnclosingClass() != null
-				? TypeReference.of(type.getEnclosingClass()) : null);
+	}
+
+	@Nullable
+	private static ReflectionTypeReference safeCreate(@Nullable Class<?> type) {
+		return (type != null ? new ReflectionTypeReference(type) : null);
 	}
 
 	static ReflectionTypeReference of(Class<?> type) {
@@ -47,18 +47,9 @@ public String getCanonicalName() {
 	}
 
 	@Override
-	public String getPackageName() {
-		return this.type.getPackageName();
-	}
-
-	@Override
-	public String getSimpleName() {
-		return this.type.getSimpleName();
-	}
-
-	@Override
-	public TypeReference getEnclosingType() {
-		return this.enclosing;
+	protected boolean isPrimitive() {
+		return this.type.isPrimitive() ||
+				(this.type.isArray() && this.type.getComponentType().isPrimitive());
 	}
 
 }

spring-core/src/main/java/org/springframework/aot/hint/ResourceHints.java

@@ -131,19 +131,7 @@ private ResourcePatternHint typesPatternResourceHint() {
 	}
 
 	private String toIncludePattern(TypeReference type) {
-		StringBuilder names = new StringBuilder();
-		buildName(type, names);
-		String candidate = type.getPackageName() + "." + names;
-		return candidate.replace(".", "/") + ".class";
-	}
-
-	private void buildName(@Nullable TypeReference type, StringBuilder sb) {
-		if (type == null) {
-			return;
-		}
-		String typeName = (type.getEnclosingType() != null) ? "$" + type.getSimpleName() : type.getSimpleName();
-		sb.insert(0, typeName);
-		buildName(type.getEnclosingType(), sb);
+		return type.getName().replace(".", "/") + ".class";
 	}
 
 }

spring-core/src/main/java/org/springframework/aot/hint/SimpleTypeReference.java

@@ -16,6 +16,8 @@
 
 package org.springframework.aot.hint;
 
+import java.util.List;
+
 import javax.lang.model.SourceVersion;
 
 import org.springframework.lang.Nullable;
@@ -28,21 +30,14 @@
  */
 final class SimpleTypeReference extends AbstractTypeReference {
 
-	@Nullable
-	private String canonicalName;
-
-	private final String packageName;
-
-	private final String simpleName;
+	private static final List<String> PRIMITIVE_NAMES = List.of("boolean", "byte",
+			"short", "int", "long", "char", "float", "double", "void");
 
 	@Nullable
-	private final TypeReference enclosingType;
-
+	private String canonicalName;
 
 	SimpleTypeReference(String packageName, String simpleName, @Nullable TypeReference enclosingType) {
-		this.packageName = packageName;
-		this.simpleName = simpleName;
-		this.enclosingType = enclosingType;
+		super(packageName, simpleName, enclosingType);
 	}
 
 	static SimpleTypeReference of(String className) {
@@ -63,7 +58,8 @@ static SimpleTypeReference of(String className) {
 
 	private static boolean isValidClassName(String className) {
 		for (String s : className.split("\\.", -1)) {
-			if (!SourceVersion.isIdentifier(s)) {
+			String candidate = s.replace("[", "").replace("]", "");
+			if (!SourceVersion.isIdentifier(candidate)) {
 				return false;
 			}
 		}
@@ -72,21 +68,34 @@ private static boolean isValidClassName(String className) {
 
 	private static SimpleTypeReference createTypeReference(String className) {
 		int i = className.lastIndexOf('.');
-		return (i != -1 ? new SimpleTypeReference(className.substring(0, i), className.substring(i + 1), null)
-				: new SimpleTypeReference("", className, null));
+		if (i != -1) {
+			return new SimpleTypeReference(className.substring(0, i), className.substring(i + 1), null);
+		}
+		else {
+			String packageName = isPrimitive(className) ? "java.lang" : "";
+			return new SimpleTypeReference(packageName, className, null);
+		}
 	}
 
 	@Override
 	public String getCanonicalName() {
 		if (this.canonicalName == null) {
 			StringBuilder names = new StringBuilder();
 			buildName(this, names);
-			this.canonicalName = (this.packageName.isEmpty()
-					? names.toString() : this.packageName + "." + names);
+			this.canonicalName = addPackageIfNecessary(names.toString());
 		}
 		return this.canonicalName;
 	}
 
+	@Override
+	protected boolean isPrimitive() {
+		return isPrimitive(getSimpleName());
+	}
+
+	private static boolean isPrimitive(String name) {
+		return PRIMITIVE_NAMES.stream().anyMatch(name::startsWith);
+	}
+
 	private static void buildName(@Nullable TypeReference type, StringBuilder sb) {
 		if (type == null) {
 			return;
@@ -96,19 +105,4 @@ private static void buildName(@Nullable TypeReference type, StringBuilder sb) {
 		buildName(type.getEnclosingType(), sb);
 	}
 
-	@Override
-	public String getPackageName() {
-		return this.packageName;
-	}
-
-	@Override
-	public String getSimpleName() {
-		return this.simpleName;
-	}
-
-	@Override
-	public TypeReference getEnclosingType() {
-		return this.enclosingType;
-	}
-
 }

spring-core/src/main/java/org/springframework/aot/hint/TypeReference.java

@@ -27,6 +27,12 @@
  */
 public interface TypeReference {
 
+	/**
+	 * Return the fully qualified name of this type reference.
+	 * @return the reflection target name
+	 */
+	String getName();
+
 	/**
 	 * Return the {@linkplain Class#getCanonicalName() canonical name} of this
 	 * type reference.

spring-core/src/main/java/org/springframework/aot/nativex/BasicJsonWriter.java

@@ -24,7 +24,6 @@
 import java.util.function.Consumer;
 
 import org.springframework.aot.hint.TypeReference;
-import org.springframework.lang.Nullable;
 
 /**
  * Very basic json writer for the purposes of translating runtime hints to native
@@ -133,7 +132,7 @@ else if (value instanceof List<?> list) {
 			writeArray(list, false);
 		}
 		else if (value instanceof TypeReference typeReference) {
-			this.writer.print(quote(toName(typeReference)));
+			this.writer.print(quote(typeReference.getName()));
 		}
 		else if (value instanceof CharSequence string) {
 			this.writer.print(quote(escape(string)));
@@ -150,21 +149,6 @@ private String quote(String name) {
 		return "\"" + name + "\"";
 	}
 
-	private String toName(TypeReference typeReference) {
-		StringBuilder names = new StringBuilder();
-		buildName(typeReference, names);
-		return typeReference.getPackageName() + "." + names;
-	}
-
-	private void buildName(@Nullable TypeReference type, StringBuilder sb) {
-		if (type == null) {
-			return;
-		}
-		String typeName = (type.getEnclosingType() != null) ? "$" + type.getSimpleName() : type.getSimpleName();
-		sb.insert(0, typeName);
-		buildName(type.getEnclosingType(), sb);
-	}
-
 
 	private static String escape(CharSequence input) {
 		StringBuilder builder = new StringBuilder();

spring-core/src/test/java/org/springframework/aot/generator/GeneratedTypeReferenceTests.java

@@ -16,7 +16,12 @@
 
 package org.springframework.aot.generator;
 
+import java.util.stream.Stream;
+
 import org.junit.jupiter.api.Test;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.Arguments;
+import org.junit.jupiter.params.provider.MethodSource;
 
 import org.springframework.aot.hint.TypeReference;
 import org.springframework.javapoet.ClassName;
@@ -30,6 +35,19 @@
  */
 class GeneratedTypeReferenceTests {
 
+
+	@ParameterizedTest
+	@MethodSource("reflectionTargetNames")
+	void hasSuitableReflectionTargetName(TypeReference typeReference, String binaryName) {
+		assertThat(typeReference.getName()).isEqualTo(binaryName);
+	}
+
+	static Stream<Arguments> reflectionTargetNames() {
+		return Stream.of(
+				Arguments.of(GeneratedTypeReference.of(ClassName.get("com.example", "Test")), "com.example.Test"),
+				Arguments.of(GeneratedTypeReference.of(ClassName.get("com.example", "Test", "Inner")), "com.example.Test$Inner"));
+	}
+
 	@Test
 	void createWithClassName() {
 		GeneratedTypeReference typeReference = GeneratedTypeReference.of(