Use Memory instead of abusing Strings

software/jna/SSS7.java

@@ -1,17 +1,21 @@
 import com.sun.jna.Library;
 import com.sun.jna.Native;
+import com.sun.jna.Pointer;
+import com.sun.jna.Memory;
 
 public class SSS7 {
 	private interface NativeSSS7 extends Library {
 		public int libsss7_start(String serialport);
 		public int libsss7_can_send();
-		public void libsss7_send(String data);
+		public void libsss7_send(Pointer data);
 		public int libsss7_send_failed();
 		public int libsss7_has_received();
-		public void libsss7_get_received(String data);
+		public void libsss7_get_received(Pointer data);
 		public void libsss7_stop();
 	};
 
+	public final int payloadLength = 16;
+
 	private NativeSSS7 lib;
 	private String serial;
 
@@ -28,6 +32,20 @@ public class SSS7 {
 		return this.lib.libsss7_can_send() == 1;
 	}
 
+	public void send(byte[] data) {
+		Pointer p = new Memory(this.payloadLength);
+		for(long i = 0; i < this.payloadLength; i++) {
+			if(i < data.length) {
+				p.setByte(i, data[(int) i]);
+			}
+			else {
+				p.setByte(i, (byte) 0);
+			}
+		}
+
+		this.lib.libsss7_send(p);
+	}
+
 	public boolean sendFailed() {
 		return this.lib.libsss7_send_failed() == 1;
 	}
@@ -36,9 +54,13 @@ public class SSS7 {
 		return this.lib.libsss7_has_received() == 1;
 	}
 
-	public String getReceived() {
-		String tmp = new String();
-		this.lib.libsss7_get_received(tmp);
-		return tmp;
+	public byte[] getReceived() {
+		Pointer p = new Memory(this.payloadLength);
+		this.lib.libsss7_get_received(p);
+		return p.getByteArray(0, this.payloadLength);
+	}
+
+	public void stop() {
+		this.lib.libsss7_stop();
 	}
 }

software/jna/SSS7Test.java

@@ -9,5 +9,17 @@ public class SSS7Test {
 
 		bus.start();
 
+		while(!bus.canSend());
+		bus.send("Hallo Java".getBytes());
+		while(!bus.canSend());
+
+
+		while(!bus.hasReceived());
+		byte[] data  = bus.getReceived();
+		String str = new String(data);
+		System.out.println(str);
+
+
+		bus.stop();
 	}
 }