Add Javadocs for resolver

Author: filip26

src/main/java/com/apicatalog/did/resolver/DidResolutionException.java

@@ -2,47 +2,103 @@
 
 import com.apicatalog.did.Did;
 
+/**
+ * Exception thrown during DID resolution.
+ * <p>
+ * Indicates resolution failures such as invalid input, not found, unsupported
+ * representation, or internal errors.
+ * </p>
+ */
 public class DidResolutionException extends Exception {
 
     private static final long serialVersionUID = -7104603698482015381L;
 
+    /**
+     * Standard resolution error codes.
+     */
     public enum Code {
-        InvalidDid,
+        /** The DID method resolution is not supported. */
+        UnsupportedMethod,
+
+        /** The DID could not be found. */
         NotFound,
-        RepresentationNotSupported,
+
+        /** An internal error occurred. */
         Internal,
     }
 
     protected final Did did;
     protected final Code code;
 
+    /**
+     * Creates a new resolution exception with a DID and code.
+     *
+     * @param did  the DID being resolved (may be {@code null})
+     * @param code error code
+     */
     public DidResolutionException(Did did, Code code) {
         this.did = did;
         this.code = code;
     }
 
+    /**
+     * Creates a new resolution exception with a message.
+     *
+     * @param did     the DID being resolved (may be {@code null})
+     * @param code    error code
+     * @param message detail message
+     */
     public DidResolutionException(Did did, Code code, String message) {
         super(message);
         this.did = did;
         this.code = code;
     }
 
+    /**
+     * Creates a new resolution exception with a cause.
+     * <p>
+     * Code is set to {@link Code#Internal}.
+     * </p>
+     *
+     * @param did the DID being resolved (may be {@code null})
+     * @param e   the cause
+     */
     public DidResolutionException(Did did, Throwable e) {
         super(e);
         this.did = did;
         this.code = Code.Internal;
     }
 
+    /**
+     * Creates a new resolution exception with a message and cause.
+     * <p>
+     * Code is set to {@link Code#Internal}.
+     * </p>
+     *
+     * @param did     the DID being resolved (may be {@code null})
+     * @param message detail message
+     * @param e       the cause
+     */
     public DidResolutionException(Did did, String message, Throwable e) {
         super(message, e);
         this.did = did;
         this.code = Code.Internal;
     }
 
+    /**
+     * Returns the DID that failed to resolve.
+     *
+     * @return the DID, or {@code null}
+     */
     public Did getDid() {
         return did;
     }
 
+    /**
+     * Returns the resolution error code.
+     *
+     * @return error code
+     */
     public Code getCode() {
         return code;
     }

src/main/java/com/apicatalog/did/resolver/DidResolver.java

@@ -4,22 +4,17 @@
 import com.apicatalog.did.document.DidDocument;
 
 /**
- * Performs {@link Did} resolution by expanding {@link Did} into
- * {@link DidDocument}.
- *
- * @see <a href="https://www.w3.org/TR/did-core/#dfn-did-resolvers">DID
- *      resolvers</a>
+ * A <a href="https://www.w3.org/TR/did-core/#dfn-did-resolvers">DID
+ * Resolver</a> expands a {@link Did} into a corresponding {@link DidDocument}.
  */
 public interface DidResolver {
 
     /**
-     * Resolves the given {@link Did} into {@link DidDocument}
+     * Resolves the given DID into a {@link DidDocument}.
      *
-     * @param did To resolve
-     * @return a new {@link DidDocument} instance
-     * 
-     * @throws IllegalArgumentException if the given DID cannot be resolved
-     * @throws DidResolutionException
+     * @param did the DID to resolve (must not be {@code null})
+     * @return the resolution result as a {@link ResolvedDidDocument}
+     * @throws DidResolutionException if resolution fails
      */
     ResolvedDidDocument resolve(Did did) throws DidResolutionException;
 }

src/main/java/com/apicatalog/did/resolver/ResolvedDidDocument.java

@@ -2,18 +2,51 @@
 
 import com.apicatalog.did.document.DidDocument;
 
+/**
+ * Result of a DID resolution process.
+ * <p>
+ * Contains the resolved {@link DidDocument} and optional
+ * {@link DidDocumentMetadata}.
+ * </p>
+ *
+ * @see <a href="https://www.w3.org/TR/did-core/#did-resolution">DID
+ *      Resolution</a>
+ */
 public interface ResolvedDidDocument {
 
+    /**
+     * Returns the resolved DID Document.
+     *
+     * @return the DID Document (never {@code null})
+     */
     DidDocument document();
-    
+
+    /**
+     * Returns resolution metadata associated with the DID Document.
+     *
+     * @return metadata, or {@code null} if none
+     */
     default DidDocumentMetadata metadata() {
         return null;
     }
 
+    /**
+     * Creates a resolution result containing only a document.
+     *
+     * @param document the resolved DID Document
+     * @return a new {@code ResolvedDidDocument}
+     */
     static ResolvedDidDocument of(DidDocument document) {
         return new ImmutableResolvedDocument(document, null);
     }
-    
+
+    /**
+     * Creates a resolution result containing a document and metadata.
+     *
+     * @param document the resolved DID Document
+     * @param meta     associated metadata (may be {@code null})
+     * @return a new {@code ResolvedDidDocument}
+     */
     static ResolvedDidDocument of(DidDocument document, DidDocumentMetadata meta) {
         return new ImmutableResolvedDocument(document, meta);
     }

src/main/java/com/apicatalog/did/resolver/package-info.java

@@ -0,0 +1,18 @@
+/**
+ * DID Resolution interfaces and exceptions.
+ * <p>
+ * Provides abstractions for resolving Decentralized Identifiers (DIDs) into DID
+ * Documents and associated metadata, following the
+ * <a href="https://www.w3.org/TR/did-core/#did-resolution">DID Resolution</a>
+ * specification.
+ * </p>
+ *
+ * <ul>
+ * <li>{@link com.apicatalog.did.resolver.DidResolver} — DID resolution API</li>
+ * <li>{@link com.apicatalog.did.resolver.ResolvedDidDocument} — resolution
+ * result</li>
+ * <li>{@link com.apicatalog.did.resolver.DidResolutionException} — resolution
+ * errors</li>
+ * </ul>
+ */
+package com.apicatalog.did.resolver;