Split Iterator from PortRange into seperate mutable class. so Portrange

is a clean Object that is immutable and can create as many iterators as
it wants without breaking.

1 files changed, 38 insertions, 0 deletions

diff --git a/src/main/java/com/it_jaros/jscanner/PortRangeIterator.java b/src/main/java/com/it_jaros/jscanner/PortRangeIterator.java
new file mode 100644
index 0000000..6690957
--- /dev/null
+++ b/src/main/java/com/it_jaros/jscanner/PortRangeIterator.java
@@ -0,0 +1,38 @@
+package com.it_jaros.jscanner;
+
+import java.util.BitSet;
+import java.util.Iterator;
+import java.util.NoSuchElementException;
+
+import static com.it_jaros.jscanner.PortRange.MAX_PORT;
+import static com.it_jaros.jscanner.PortRange.MIN_PORT;
+
+public class PortRangeIterator implements Iterator<Integer> {
+
+    private int currentPortCursor;
+    private int done = 0;
+    private final BitSet availablePorts = new BitSet(MAX_PORT);
+
+    PortRangeIterator(BitSet specifiedPorts) {
+        availablePorts.or(specifiedPorts);
+        currentPortCursor = availablePorts.nextSetBit(MIN_PORT);
+    }
+
+    @Override
+    public Integer next() {
+        int p = availablePorts.nextSetBit(currentPortCursor);
+        if (p > 0) {
+            availablePorts.clear(p);
+            currentPortCursor = p + 1;
+            done++;
+            return p;
+        }
+
+        throw new NoSuchElementException("Reached end of port range");
+    }
+
+    @Override
+    public boolean hasNext() {
+        return availablePorts.nextSetBit(currentPortCursor) > 0;
+    }
+}