2 files changed, 52 insertions, 35 deletions

diff --git a/src/main/java/com/it_jaros/jns/CliPrinter.java b/src/main/java/com/it_jaros/jns/CliPrinter.java
index 4b3a247..fded599 100644
--- a/src/main/java/com/it_jaros/jns/CliPrinter.java
+++ b/src/main/java/com/it_jaros/jns/CliPrinter.java
@@ -1,12 +1,15 @@
 package com.it_jaros.jns;
 
 import com.it_jaros.jns.scan.Scan;
+import com.it_jaros.jns.scan.domain.PortList;
 import com.it_jaros.jns.scan.domain.ScanFailure;
 import com.it_jaros.jns.scan.domain.ScanResult;
 import com.it_jaros.jns.scan.service.ServiceType;
 
 import java.io.BufferedReader;
 import java.io.InputStreamReader;
+import java.util.ArrayList;
+import java.util.Collections;
 import java.util.List;
 import java.util.Map;
 import java.util.concurrent.Executors;
@@ -54,22 +57,15 @@ public class CliPrinter {
         if (result.errors().isEmpty()) return;
 
         StringBuilder sb = new StringBuilder();
-        sb.append(String.format(
-                "%s | errors: %d%n",
-                result.host(),
-                result.errors().size()
-        ));
-        String errors = result.errors().stream().map((ScanFailure error) -> String.format(
-                "\t%dx %s: %s ports: %s",
-                error.ports().size(),
-                error.exception().type(),
-                error.exception().message(),
-                error.ports().stream().sorted().map(String::valueOf).collect(Collectors.joining(","))
-        )).collect(Collectors.joining("\n"));
-        sb.append(errors);
-        sb.append("\n");
+        sb.append(result.host()).append(" | errors: ").append(result.errors().size()).append('\n');
+        for (ScanFailure error : result.errors()) {
+            sb.append('\t').append(error.ports().size()).append("x ")
+                    .append(error.exception().type()).append(": ").append(error.exception().message())
+                    .append(" ports: ").append(joinSortedPorts(error.ports())).append('\n');
+        }
+        sb.append('\n');
 
-        System.err.println(sb);
+        System.err.print(sb);
         System.err.flush();
     }
 
@@ -79,37 +75,54 @@ public class CliPrinter {
         }
 
         StringBuilder sb = new StringBuilder();
-        sb.append(result.host());
-        sb.append("\n");
+        sb.append(result.host()).append('\n');
         if (!result.openPorts().isEmpty()) {
-            sb.append(
-                    String.format("\t (%d) open:\t%s%n", result.openPorts().size(), map(result.openPorts().getPorts(), result.bannerRecognition()))
-            );
+            sb.append("\t (").append(result.openPorts().size()).append(") open:\t")
+                    .append(joinOpenPorts(result.openPorts(), result.bannerRecognition())).append('\n');
         }
         if (showFilteredPorts && !result.filteredPorts().isEmpty()) {
-            sb.append(
-                    String.format("\t (%d) filtered:\t%s%n", result.filteredPorts().size(), map(result.filteredPorts().getPorts()))
-            );
+            sb.append("\t (").append(result.filteredPorts().size()).append(") filtered:\t")
+                    .append(joinPorts(result.filteredPorts())).append('\n');
         }
-        sb.append("\n");
-        System.out.println(sb);
+        sb.append('\n');
+        System.out.print(sb);
         System.out.flush();
     }
 
-    private static String map(List<Integer> ports) {
-        return ports.stream().map(String::valueOf).collect(Collectors.joining(","));
+    private static String joinPorts(PortList portList) {
+        StringBuilder sb = new StringBuilder();
+        boolean first = true;
+        for (int port = portList.nextSetBit(0); port >= 0; port = portList.nextSetBit(port + 1)) {
+            if (!first) {
+                sb.append(',');
+            }
+            sb.append(port);
+            first = false;
+        }
+        return sb.toString();
     }
 
-    private static String map(List<Integer> ports, Map<Integer, ServiceType> bannerRecognition) {
-        return ports.stream().map(port -> {
-            ServiceType serviceType = bannerRecognition.getOrDefault(port, ServiceType.UNKNOWN);
-
-            if (serviceType == ServiceType.UNKNOWN) {
-                return String.valueOf(port);
+    private static String joinOpenPorts(PortList portList, Map<Integer, ServiceType> bannerRecognition) {
+        StringBuilder sb = new StringBuilder();
+        boolean first = true;
+        for (int port = portList.nextSetBit(0); port >= 0; port = portList.nextSetBit(port + 1)) {
+            if (!first) {
+                sb.append(',');
+            }
+            sb.append(port);
+            ServiceType serviceType = bannerRecognition.get(port);
+            if (serviceType != null && serviceType != ServiceType.UNKNOWN) {
+                sb.append('/').append(serviceType.name().toLowerCase());
             }
+            first = false;
+        }
+        return sb.toString();
+    }
 
-            return port + "/" + serviceType.name().toLowerCase();
-        }).collect(Collectors.joining(","));
+    private static String joinSortedPorts(List<Integer> ports) {
+        List<Integer> sorted = new ArrayList<>(ports);
+        Collections.sort(sorted);
+        return sorted.stream().map(String::valueOf).collect(Collectors.joining(","));
     }
 
     private static int getColumnWidth() {
diff --git a/src/main/java/com/it_jaros/jns/scan/domain/PortList.java b/src/main/java/com/it_jaros/jns/scan/domain/PortList.java
index 69a6bfc..837ce6b 100644
--- a/src/main/java/com/it_jaros/jns/scan/domain/PortList.java
+++ b/src/main/java/com/it_jaros/jns/scan/domain/PortList.java
@@ -9,6 +9,10 @@ import java.util.List;
 public class PortList {
     private final BitSet ports;
 
+    public int nextSetBit(int fromIndex) {
+        return ports.nextSetBit(fromIndex);
+    }
+
     public PortList(BitSet ports) {
         this.ports = ports;
     }