Added support for setting ping TTL.

library/src/main/java/com/stealthcopter/networktools/Ping.java

@@ -1,5 +1,6 @@
 package com.stealthcopter.networktools;
 
+import com.stealthcopter.networktools.ping.PingOptions;
 import com.stealthcopter.networktools.ping.PingResult;
 import com.stealthcopter.networktools.ping.PingStats;
 import com.stealthcopter.networktools.ping.PingTools;
@@ -34,7 +35,7 @@ public interface PingListener {
 
     private String addressString = null;
     private InetAddress address;
-    private int timeOutMillis = 1000;
+    private final PingOptions pingOptions = new PingOptions();
     private int delayBetweenScansMillis = 0;
     private int times = 1;
     private boolean cancelled = false;
@@ -74,7 +75,7 @@ public static Ping onAddress(InetAddress ia) {
      */
     public Ping setTimeOutMillis(int timeOutMillis) {
         if (timeOutMillis < 0) throw new IllegalArgumentException("Times cannot be less than 0");
-        this.timeOutMillis = timeOutMillis;
+        pingOptions.setTimeoutMillis(timeOutMillis);
         return this;
     }
 
@@ -91,6 +92,18 @@ public Ping setDelayMillis(int delayBetweenScansMillis) {
         return this;
     }
 
+    /**
+     * Set the time to live
+     *
+     * @param timeToLive - the TTL for each ping
+     * @return this object to allow chaining
+     */
+    public Ping setTimeToLive(int timeToLive) {
+        if (timeToLive < 1) throw new IllegalArgumentException("TTL cannot be less than 1");
+        pingOptions.setTimeToLive(timeToLive);
+        return this;
+    }
+
     /**
      * Set number of times to ping the address
      *
@@ -145,7 +158,7 @@ public void cancel() {
     public PingResult doPing() throws UnknownHostException {
         cancelled = false;
         resolveAddressString();
-        return PingTools.doPing(address, timeOutMillis);
+        return PingTools.doPing(address, pingOptions);
     }
 
     /**
@@ -183,7 +196,7 @@ public void run() {
 
                 // times == 0 is the case that we can continuous scanning
                 while (noPings > 0 || times == 0) {
-                    PingResult pingResult = PingTools.doPing(address, timeOutMillis);
+                    PingResult pingResult = PingTools.doPing(address, pingOptions);
 
                     if (pingListener != null) {
                         pingListener.onResult(pingResult);

library/src/main/java/com/stealthcopter/networktools/ping/PingNative.java

@@ -16,13 +16,13 @@ public class PingNative {
     private PingNative() {
     }
 
-    public static PingResult ping(InetAddress host, int timeOutMillis) throws IOException, InterruptedException {
+    public static PingResult ping(InetAddress host, PingOptions pingOptions) throws IOException, InterruptedException {
         PingResult pingResult = new PingResult(host);
         StringBuilder echo = new StringBuilder();
         Runtime runtime = Runtime.getRuntime();
 
-        int timeoutSeconds = timeOutMillis / 1000;
-        if (timeoutSeconds < 0) timeoutSeconds = 1;
+        int timeoutSeconds = Math.max(pingOptions.getTimeoutMillis() / 1000, 1);
+        int ttl = Math.max(pingOptions.getTimeToLive(), 1);
 
         String address = host.getHostAddress();
         String pingCommand = "ping";
@@ -40,7 +40,7 @@ public static PingResult ping(InetAddress host, int timeOutMillis) throws IOExce
             address = host.getHostName();
         }
 
-        Process proc = runtime.exec(pingCommand + " -c 1 -w " + timeoutSeconds + " " + address);
+        Process proc = runtime.exec(pingCommand + " -c 1 -w " + timeoutSeconds + " -w" + ttl + " " + address);
         proc.waitFor();
         int exit = proc.exitValue();
         String pingError;

library/src/main/java/com/stealthcopter/networktools/ping/PingOptions.java

@@ -0,0 +1,27 @@
+package com.stealthcopter.networktools.ping;
+
+public class PingOptions {
+    private int timeoutMillis;
+    private int timeToLive;
+
+     public PingOptions() {
+         timeToLive = 128;
+         timeoutMillis = 1000;
+     }
+
+    public int getTimeoutMillis() {
+        return timeoutMillis;
+    }
+
+    public void setTimeoutMillis(int timeoutMillis) {
+        this.timeoutMillis = Math.max(timeoutMillis, 1000);
+    }
+
+    public int getTimeToLive() {
+        return timeToLive;
+    }
+
+    public void setTimeToLive(int timeToLive) {
+        this.timeToLive = Math.max(timeToLive, 1);
+    }
+}

library/src/main/java/com/stealthcopter/networktools/ping/PingTools.java

@@ -2,6 +2,7 @@
 
 import java.io.IOException;
 import java.net.InetAddress;
+import java.net.NetworkInterface;
 
 /**
  * Created by mat on 09/12/15.
@@ -18,14 +19,14 @@ private PingTools() {
      * on failure.
      *
      * @param ia            - address to ping
-     * @param timeOutMillis - timeout in millisecdonds
+     * @param pingOptions   - ping command options
      * @return - the ping results
      */
-    public static PingResult doPing(InetAddress ia, int timeOutMillis) {
+    public static PingResult doPing(InetAddress ia, PingOptions pingOptions) {
 
         // Try native ping first
         try {
-            return PingTools.doNativePing(ia, timeOutMillis);
+            return PingTools.doNativePing(ia, pingOptions);
         } catch (InterruptedException e) {
             PingResult pingResult = new PingResult(ia);
             pingResult.isReachable = false;
@@ -35,21 +36,21 @@ public static PingResult doPing(InetAddress ia, int timeOutMillis) {
         }
 
         // Fallback to java based ping
-        return PingTools.doJavaPing(ia, timeOutMillis);
+        return PingTools.doJavaPing(ia, pingOptions);
     }
 
 
     /**
      * Perform a ping using the native ping binary
      *
      * @param ia            - address to ping
-     * @param timeOutMillis - timeout in millisecdonds
+     * @param pingOptions   - ping command options
      * @return - the ping results
      * @throws IOException
      * @throws InterruptedException
      */
-    public static PingResult doNativePing(InetAddress ia, int timeOutMillis) throws IOException, InterruptedException {
-        return PingNative.ping(ia, timeOutMillis);
+    public static PingResult doNativePing(InetAddress ia, PingOptions pingOptions) throws IOException, InterruptedException {
+        return PingNative.ping(ia, pingOptions);
     }
 
     /**
@@ -58,14 +59,14 @@ public static PingResult doNativePing(InetAddress ia, int timeOutMillis) throws
      * on port 7 (Echo) of the remote host.
      *
      * @param ia            - address to ping
-     * @param timeOutMillis - timeout in millisecdonds
+     * @param pingOptions   - ping command options
      * @return - the ping results
      */
-    public static PingResult doJavaPing(InetAddress ia, int timeOutMillis) {
+    public static PingResult doJavaPing(InetAddress ia, PingOptions pingOptions) {
         PingResult pingResult = new PingResult(ia);
         try {
             long startTime = System.nanoTime();
-            final boolean reached = ia.isReachable(timeOutMillis);
+            final boolean reached = ia.isReachable(null, pingOptions.getTimeToLive(), pingOptions.getTimeoutMillis());
             pingResult.timeTaken = (System.nanoTime() - startTime) / 1e6f;
             pingResult.isReachable = reached;
             if (!reached) pingResult.error = "Timed Out";