# NOT A PART OF SEAMONKEY IN ANY WAY

Some new, some old filres copiedfrom Rhino to form start of prototyping
environment for Project Brenda


git-svn-id: svn://10.0.0.236/trunk@27571 18797224-902f-48f8-a5cc-f745e15eee43

mozilla/js/js2/java/BinaryDigitReader.java

@@ -0,0 +1,43 @@
+/* -*- Mode: java; tab-width: 8 -*-
+ * Copyright © 1997, 1998 Netscape Communications Corporation,
+ * All Rights Reserved.
+ */
+
+final class BinaryDigitReader {
+    int lgBase;			// Logarithm of base of number
+    int digit;			// Current digit value in radix given by base
+    int digitPos;		// Bit position of last bit extracted from digit
+    String digits;		// String containing the digits
+    int start;			// Index of the first remaining digit
+    int end;			// Index past the last remaining digit
+
+    BinaryDigitReader(int base, String digits, int start, int end) {
+        lgBase = 0;
+        while (base != 1) {
+            lgBase++;
+            base >>= 1;
+        }
+        digitPos = 0;
+        this.digits = digits;
+        this.start = start;
+        this.end = end;
+    }
+
+    /* Return the next binary digit from the number or -1 if done */
+    int getNextBinaryDigit()
+    {
+        if (digitPos == 0) {
+            if (start == end)
+                return -1;
+
+            char c = digits.charAt(start++);
+            if ('0' <= c && c <= '9')
+                digit = c - '0';
+            else if ('a' <= c && c <= 'z')
+                digit = c - 'a' + 10;
+            else digit = c - 'A' + 10;
+            digitPos = lgBase;
+        }
+        return digit >> --digitPos & 1;
+    }
+}