added _reEncryptInstructionFile boolean field to builder in AES + RSA keyrings

Author: Anirav Kareddy

src/main/java/software/amazon/encryption/s3/materials/AesKeyring.java

@@ -183,6 +183,7 @@ public MaterialsDescription getMaterialsDescription() {
 
   public static class Builder extends S3Keyring.Builder<AesKeyring, Builder> {
         private SecretKey _wrappingKey;
+        private boolean _reEncryptInstructionFile = false;
 
         private Builder() {
             super();
@@ -203,8 +204,16 @@ public Builder wrappingKey(final SecretKey wrappingKey) {
             _wrappingKey = wrappingKey;
             return builder();
         }
+        public Builder reEncryptInstructionFile(boolean reEncryptInstructionFile) {
+            _reEncryptInstructionFile = reEncryptInstructionFile;
+            return builder();
+
+        }
 
         public AesKeyring build() {
+            if (_reEncryptInstructionFile && _materialsDescription == null) {
+                throw new S3EncryptionClientException("Materials description must be provided for re-encrypt instruction file!");
+            }
             return new AesKeyring(this);
         }
     }

src/main/java/software/amazon/encryption/s3/materials/RsaKeyring.java

@@ -203,6 +203,7 @@ public MaterialsDescription getMaterialsDescription() {
 
   public static class Builder extends S3Keyring.Builder<S3Keyring, Builder> {
         private PartialRsaKeyPair _partialRsaKeyPair;
+        private boolean _reEncryptInstructionFile = false;
 
         private Builder() {
             super();
@@ -217,10 +218,18 @@ public Builder wrappingKeyPair(final PartialRsaKeyPair partialRsaKeyPair) {
             _partialRsaKeyPair = partialRsaKeyPair;
             return builder();
         }
+        public Builder reEncryptInstructionFile(final boolean reEncryptInstructionFile) {
+            _reEncryptInstructionFile = reEncryptInstructionFile;
+            return builder();
+        }
 
         public RsaKeyring build() {
+            if (_reEncryptInstructionFile && _materialsDescription == null) {
+                throw new S3EncryptionClientException("Materials description must be provided for re-encrypt instruction file!");
+            }
             return new RsaKeyring(this);
         }
-    }
+
+  }
 
 }