Added PortRange class that generates ports to scan

1 files changed, 67 insertions, 0 deletions

diff --git a/src/main/java/com/it_jaros/networkScanner/PortRange.java b/src/main/java/com/it_jaros/networkScanner/PortRange.java
new file mode 100644
index 0000000..cdef5cf
--- /dev/null
+++ b/src/main/java/com/it_jaros/networkScanner/PortRange.java
@@ -0,0 +1,67 @@
+package com.it_jaros.networkScanner;
+
+import java.util.BitSet;
+import java.util.NoSuchElementException;
+
+public class PortRange {
+
+    private static final int MIN_PORT = 1;
+    private static final int MAX_PORT = 65535;
+    private final BitSet portsRange = new BitSet(MAX_PORT);
+    private final BitSet available = new BitSet(MAX_PORT);
+
+    private int cursor;
+    private int done = 0;
+    private int total = 0;
+
+    public PortRange(String ports) {
+        if (ports == null || "".equals(ports)) {
+            // keep defaults
+            portsRange.set(1, 1024 + 1);
+            return;
+        }
+
+        String[] splitComma = ports.split(",");
+        for (String commaValue: splitComma) {
+            if (commaValue.contains("-")) {
+                String[] splitRange = commaValue.split("-");
+                if (splitRange.length > 2) {
+                    throw new IllegalArgumentException(String.format("Argument contains too many '-'' %s", commaValue));
+                }
+                
+                int start = Integer.parseInt(splitRange[0]);
+                int end = Integer.parseInt(splitRange[1]);
+                portsRange.set(start, end + 1);
+            } else {
+                portsRange.set(Integer.parseInt(commaValue));
+            }
+        }
+        
+        available.or(portsRange);
+        cursor = available.nextSetBit(MIN_PORT);
+    }
+
+    public synchronized int next() {
+        int p = available.nextSetBit(cursor);
+        if (p > 0) {
+            available.clear(p);
+            cursor = p + 1;
+            done++;
+            return p;
+        }
+
+        throw new NoSuchElementException("Reached end of port range");
+    }
+
+    public synchronized boolean hasNext() {
+        return available.nextSetBit(cursor) > 0;
+    }
+
+    public int getTotal() {
+        return portsRange.cardinality();
+    }
+
+    public int getDone() {
+        return done;
+    }
+}