BigInteger.java (randBytes): New method.

2001-08-17  Mark J Roberts  <mjr@anarcast.net>

	* java/math/BigInteger.java (randBytes): New method.
	(BigInteger(int,Random)): Use randBytes.

From-SVN: r44984

diff --git a/libjava/ChangeLog b/libjava/ChangeLog
index 12c86fc5cc76b16b0cc8bb453b2ec714835fc847..1567a3d1af719f6770d49d915e7820934f8b4896 100644 (file)
--- a/libjava/ChangeLog
+++ b/libjava/ChangeLog
@@ -1,3 +1,8 @@
+2001-08-17  Mark J Roberts  <mjr@anarcast.net>
+
+       * java/math/BigInteger.java (randBytes): New method.
+       (BigInteger(int,Random)): Use randBytes.
+
 2001-08-17  Tom Tromey  <tromey@redhat.com>
 
        * gnu/gcj/convert/IOConverter.java: Add `646' alias.

diff --git a/libjava/java/math/BigInteger.java b/libjava/java/math/BigInteger.java
index e74c5e1c8ea999cec85b77af3d6f50bef7869183..b9bfee695b50b3e8d3eac697c8265036b14b2de5 100644 (file)
--- a/libjava/java/math/BigInteger.java
+++ b/libjava/java/math/BigInteger.java
@@ -143,22 +143,21 @@ public class BigInteger extends Number implements Comparable
   }
 
   public BigInteger(int numBits, Random rnd)
+  {
+    this(1, randBytes(numBits, rnd));
+  }
+
+  private static byte[] randBytes(int numBits, Random rnd)
   {
     if (numBits < 0)
       throw new IllegalArgumentException();
 
-    // Result is always positive so tack on an extra zero word, it will be
-    // canonicalized out later if necessary.
-    int nwords = numBits / 32 + 2;
-    words = new int[nwords];
-    words[--nwords] = 0;
-    words[--nwords] = rnd.nextInt() >>> (numBits % 32);
-    while (--nwords >= 0)
-      words[nwords] = rnd.nextInt();
-
-    BigInteger result = make(words, words.length);
-    this.ival = result.ival;
-    this.words = result.words;
+    int extra = numBits % 8;
+    byte[] b = new byte[numBits / 8 + (extra > 0 ? 1 : 0)];
+    rnd.nextBytes(b);
+    if (extra > 0)
+      b[0] &= ~((~0) << (8 - extra));
+    return b;
   }
 
   public BigInteger(int bitLength, int certainty, Random rnd)