1 files changed, 33 insertions, 20 deletions

diff --git a/bcprov/src/main/java/org/bouncycastle/asn1/cms/KeyAgreeRecipientInfo.java b/bcprov/src/main/java/org/bouncycastle/asn1/cms/KeyAgreeRecipientInfo.java
index c6e5744..224932a 100644
--- a/bcprov/src/main/java/org/bouncycastle/asn1/cms/KeyAgreeRecipientInfo.java
+++ b/bcprov/src/main/java/org/bouncycastle/asn1/cms/KeyAgreeRecipientInfo.java
@@ -11,6 +11,22 @@ import org.bouncycastle.asn1.DERSequence;
 import org.bouncycastle.asn1.DERTaggedObject;
 import org.bouncycastle.asn1.x509.AlgorithmIdentifier;
 
+/**
+ * <a href="http://tools.ietf.org/html/rfc5652#section-6.2.2">RFC 5652</a>:
+ * Content encryption key delivery mechanisms.
+ * <p>
+ * <pre>
+ * KeyAgreeRecipientInfo ::= SEQUENCE {
+ *     version CMSVersion,  -- always set to 3
+ *     originator [0] EXPLICIT OriginatorIdentifierOrKey,
+ *     ukm [1] EXPLICIT UserKeyingMaterial OPTIONAL,
+ *     keyEncryptionAlgorithm KeyEncryptionAlgorithmIdentifier,
+ *     recipientEncryptedKeys RecipientEncryptedKeys 
+ * }
+ *
+ * UserKeyingMaterial ::= OCTET STRING
+ * </pre>
+ */
 public class KeyAgreeRecipientInfo
     extends ASN1Object
 {
@@ -32,7 +48,10 @@ public class KeyAgreeRecipientInfo
         this.keyEncryptionAlgorithm = keyEncryptionAlgorithm;
         this.recipientEncryptedKeys = recipientEncryptedKeys;
     }
-    
+
+    /**
+     * @deprecated use getInstance()
+     */
     public KeyAgreeRecipientInfo(
         ASN1Sequence seq)
     {
@@ -55,7 +74,7 @@ public class KeyAgreeRecipientInfo
     }
     
     /**
-     * return a KeyAgreeRecipientInfo object from a tagged object.
+     * Return a KeyAgreeRecipientInfo object from a tagged object.
      *
      * @param obj the tagged object holding the object we want.
      * @param explicit true if the object is meant to be explicitly
@@ -71,7 +90,14 @@ public class KeyAgreeRecipientInfo
     }
     
     /**
-     * return a KeyAgreeRecipientInfo object from the given object.
+     * Return a KeyAgreeRecipientInfo object from the given object.
+     * <p>
+     * Accepted inputs:
+     * <ul>
+     * <li> null &rarr; null
+     * <li> {@link KeyAgreeRecipientInfo} object
+     * <li> {@link org.bouncycastle.asn1.ASN1Sequence#getInstance(java.lang.Object) ASN1Sequence} input formats with KeyAgreeRecipientInfo structure inside
+     * </ul>
      *
      * @param obj the object we want converted.
      * @exception IllegalArgumentException if the object cannot be converted.
@@ -79,19 +105,17 @@ public class KeyAgreeRecipientInfo
     public static KeyAgreeRecipientInfo getInstance(
         Object obj)
     {
-        if (obj == null || obj instanceof KeyAgreeRecipientInfo)
+        if (obj instanceof KeyAgreeRecipientInfo)
         {
             return (KeyAgreeRecipientInfo)obj;
         }
         
-        if (obj instanceof ASN1Sequence)
+        if (obj != null)
         {
-            return new KeyAgreeRecipientInfo((ASN1Sequence)obj);
+            return new KeyAgreeRecipientInfo(ASN1Sequence.getInstance(obj));
         }
         
-        throw new IllegalArgumentException(
-        "Illegal object in KeyAgreeRecipientInfo: " + obj.getClass().getName());
-
+        return null;
     } 
 
     public ASN1Integer getVersion()
@@ -121,17 +145,6 @@ public class KeyAgreeRecipientInfo
 
     /** 
      * Produce an object suitable for an ASN1OutputStream.
-     * <pre>
-     * KeyAgreeRecipientInfo ::= SEQUENCE {
-     *     version CMSVersion,  -- always set to 3
-     *     originator [0] EXPLICIT OriginatorIdentifierOrKey,
-     *     ukm [1] EXPLICIT UserKeyingMaterial OPTIONAL,
-     *     keyEncryptionAlgorithm KeyEncryptionAlgorithmIdentifier,
-     *     recipientEncryptedKeys RecipientEncryptedKeys 
-     * }
-     *
-     * UserKeyingMaterial ::= OCTET STRING
-     * </pre>
      */
     public ASN1Primitive toASN1Primitive()
     {