1 files changed, 42 insertions, 0 deletions
diff --git a/container-search/src/main/java/com/yahoo/fs4/HexByteIterator.java b/container-search/src/main/java/com/yahoo/fs4/HexByteIterator.java
new file mode 100644
index 00000000000..78ba857c475
--- /dev/null
+++ b/container-search/src/main/java/com/yahoo/fs4/HexByteIterator.java
@@ -0,0 +1,42 @@
+// Copyright 2017 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.fs4;
+
+import java.nio.ByteBuffer;
+import java.util.Iterator;
+
+/**
+ * Provides sequential access to each byte of a buffer
+ * as a hexadecimal string of length 2.
+ *
+ * @author Tony Vaagenes
+ */
+public final class HexByteIterator implements Iterator<String> {
+    private final ByteBuffer buffer;
+
+    private String hexByte(byte b) {
+        final int unsignedValue = ((int)b) & 0xff;
+        String s = Integer.toHexString(unsignedValue).toUpperCase();
+
+        boolean singleChar = unsignedValue < 0x10;
+        if (singleChar)
+            return '0' + s;
+        else
+            return s;
+    }
+
+    public boolean hasNext() {
+        return buffer.hasRemaining();
+    }
+
+    public String next() {
+        return hexByte(buffer.get());
+    }
+
+    public void remove() {
+        throw new UnsupportedOperationException();
+    }
+
+    public HexByteIterator(ByteBuffer buffer) {
+        this.buffer = buffer.slice();
+    }
+}