Simplify BigIntegers.asUnsignedByteArray implementation

1 files changed, 12 insertions, 30 deletions

diff --git a/core/src/main/java/org/bouncycastle/util/BigIntegers.java b/core/src/main/java/org/bouncycastle/util/BigIntegers.java
index 6a8a620e..f7f7e68b 100644
--- a/core/src/main/java/org/bouncycastle/util/BigIntegers.java
+++ b/core/src/main/java/org/bouncycastle/util/BigIntegers.java
@@ -40,43 +40,25 @@ public final class BigIntegers
      * @param value value to be converted.
      * @return a byte array without a leading zero byte if present in the signed encoding.
      */
-    public static byte[] asUnsignedByteArray(
-        int        length,
-        BigInteger value)
+    public static byte[] asUnsignedByteArray(int length, BigInteger value)
     {
         byte[] bytes = value.toByteArray();
-
-        if (bytes[0] == 0)
+        if (bytes.length == length)
         {
-            if (bytes.length - 1 > length)
-            {
-                throw new IllegalArgumentException("standard length exceeded for value");
-            }
-
-            byte[] tmp = new byte[length];
-
-            System.arraycopy(bytes, 1, tmp, tmp.length - (bytes.length - 1), bytes.length - 1);
-
-            return tmp;
+            return bytes;
         }
-        else
-        {
-            if (bytes.length == length)
-            {
-                return bytes;
-            }
-
-            if (bytes.length > length)
-            {
-                throw new IllegalArgumentException("standard length exceeded for value");
-            }
-
-            byte[] tmp = new byte[length];
 
-            System.arraycopy(bytes, 0, tmp, tmp.length - bytes.length, bytes.length);
+        int start = bytes[0] == 0 ? 1 : 0;
+        int count = bytes.length - start;
 
-            return tmp;
+        if (count > length)
+        {
+            throw new IllegalArgumentException("standard length exceeded for value");
         }
+
+        byte[] tmp = new byte[length];
+        System.arraycopy(bytes, start, tmp, tmp.length - count, count);
+        return tmp;
     }
 
     /**