add watch on several keys, and discard status return

src/main/java/redis/clients/jedis/BinaryClient.java

@@ -396,8 +396,8 @@ public class BinaryClient extends Connection {
         isInMulti = false;
     }
 
-    public void watch(final byte[] key) {
-        sendCommand(WATCH, key);
+    public void watch(final byte[]... keys) {
+        sendCommand(WATCH, keys);
     }
 
     public void unwatch() {

src/main/java/redis/clients/jedis/BinaryTransaction.java

@@ -5,6 +5,7 @@ import java.util.Map;
 
 public class BinaryTransaction {
     protected Client client = null;
+    protected boolean inTransaction = true;
 
     public BinaryTransaction() {
     }
@@ -424,7 +425,9 @@ public class BinaryTransaction {
         return client.getStatusCodeReply();
     }
 
-	public void discard() {
+    public String discard() {
         client.discard();
+        inTransaction = false;
+        return client.getStatusCodeReply();
     }
 }

src/main/java/redis/clients/jedis/Client.java

@@ -360,8 +360,12 @@ public class Client extends BinaryClient {
         zscore(SafeEncoder.encode(key), SafeEncoder.encode(member));
     }
 
-    public void watch(final String key) {
-        watch(SafeEncoder.encode(key));
+    public void watch(final String... keys) {
+        final byte[][] bargs = new byte[keys.length][];
+        for (int i = 0; i < bargs.length; i++) {
+            bargs[i] = SafeEncoder.encode(keys[i]);
+        }
+        watch(bargs);
     }
 
     public void sort(final String key) {

src/main/java/redis/clients/jedis/Jedis.java

@@ -1669,8 +1669,8 @@ public class Jedis extends BinaryJedis implements JedisCommands {
         client.disconnect();
     }
 
-    public String watch(final String key) {
-        client.watch(key);
+    public String watch(final String... keys) {
+        client.watch(keys);
         return client.getStatusCodeReply();
     }
 

src/test/java/redis/clients/jedis/tests/commands/TransactionCommandsTest.java

@@ -124,7 +124,7 @@ public class TransactionCommandsTest extends JedisCommandTestBase {
 
     @Test
     public void watch() throws UnknownHostException, IOException {
-        jedis.watch("mykey");
+        jedis.watch("mykey", "somekey");
         Transaction t = jedis.multi();
 
         nj.connect();
@@ -197,4 +197,11 @@ public class TransactionCommandsTest extends JedisCommandTestBase {
         jedis.multi();
         jedis.ping();
     }
+
+    @Test
+    public void discard() {
+        Transaction t = jedis.multi();
+        String status = t.discard();
+        assertEquals("OK", status);
+    }
 }