8357915: SecureRandom nextLong memory usage

Reviewed-by: wetmore

Author: koushikthirupattur

src/java.base/share/classes/java/security/SecureRandom.java

@@ -25,6 +25,7 @@
 
 package java.security;
 
+import jdk.internal.util.ByteArray;
 import sun.security.jca.GetInstance;
 import sun.security.jca.GetInstance.Instance;
 import sun.security.jca.Providers;
@@ -837,6 +838,16 @@ protected final int next(int numBits) {
         return next >>> (numBytes*8 - numBits);
     }
 
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    public long nextLong() {
+        byte[] b = new byte[8];
+        nextBytes(b); // Calls engineNextBytes internally
+        return ByteArray.getLong(b, 0);
+    }
+
     /**
      * Returns the given number of seed bytes, computed using the seed
      * generation algorithm that this class uses to seed itself.  This