test: add JUnit tests (>=90% coverage); docs: comprehensive English JavaDoc

Author: loong10k

src/main/java/org/springframework/bytebuddy/annotation/WebBound.java

@@ -22,14 +22,41 @@
 import java.lang.annotation.RetentionPolicy;
 import java.lang.annotation.Target;
 
+/**
+ * Annotation for binding data to dynamically generated endpoint classes
+ * or methods. When applied to a class or method, it associates a unique
+ * identifier ({@link #uid()}) and a JSON payload ({@link #json()}) with
+ * the annotated element, enabling data-driven endpoint generation.
+ *
+ * <p>This annotation is typically used in conjunction with
+ * {@code EndpointApiBuilder} to bind request data to dynamically
+ * constructed Spring MVC controller classes or handler methods.</p>
+ *
+ * @author [@Loong Wan](https://github.com/loong10k)
+ * @since 3.0.0
+ * @see org.springframework.bytebuddy.bytecode.EndpointApiBuilder
+ * @see org.springframework.bytebuddy.bytecode.ReactiveHandlerBuilder
+ */
 @Target({ ElementType.TYPE, ElementType.METHOD })
 @Retention(RetentionPolicy.RUNTIME)
 @Documented
 @Inherited
 public @interface WebBound {
 
+	/**
+	 * A unique identifier for the data binding, typically a primary key
+	 * or identifier used to look up data in the implementing handler.
+	 *
+	 * @return the unique identifier string, or an empty string by default
+	 */
 	String uid() default "";
 
+	/**
+	 * A JSON-formatted string containing the data payload to be bound
+	 * to the annotated element.
+	 *
+	 * @return the JSON payload string, or {@code "{}"} by default
+	 */
 	String json() default "{}";
 
 }

src/main/java/org/springframework/bytebuddy/bytecode/EndpointApi.java

@@ -1,5 +1,20 @@
 package org.springframework.bytebuddy.bytecode;
 
+/**
+ * Abstract base class for dynamically generated Spring MVC endpoint classes.
+ * This class serves as the superclass for all classes generated by
+ * {@link EndpointApiBuilder} or {@link ReactiveHandlerBuilder} using
+ * the ByteBuddy code generation library.
+ *
+ * <p>Instances of subclasses of this type are created at runtime and
+ * represent dynamically constructed controller endpoints that can be
+ * registered within a Spring application context.</p>
+ *
+ * @author [@Loong Wan](https://github.com/loong10k)
+ * @since 3.0.0
+ * @see EndpointApiBuilder
+ * @see ReactiveHandlerBuilder
+ */
 public abstract class EndpointApi {
-	
-}
+
+}