diff --git a/app/src/main/java/org/transdroid/daemon/adapters/deluge/DelugeRpcClient.java b/app/src/main/java/org/transdroid/daemon/adapters/deluge/DelugeRpcClient.java
index ffc4c6fe..aec2fb76 100644
--- a/app/src/main/java/org/transdroid/daemon/adapters/deluge/DelugeRpcClient.java
+++ b/app/src/main/java/org/transdroid/daemon/adapters/deluge/DelugeRpcClient.java
@@ -162,7 +162,7 @@ class DelugeRpcClient implements Closeable {
         if (!(responseObject instanceof List)) {
             throw new DaemonException(ExceptionType.UnexpectedResponse, responseObject.toString());
         }
-        final List response = (List) responseObject;
+        final List<?> response = (List<?>) responseObject;
 
         if (response.size() < RESPONSE_RETURN_VALUE_INDEX + 1) {
             throw new DaemonException(ExceptionType.UnexpectedResponse, responseObject.toString());
diff --git a/app/src/main/java/org/transdroid/daemon/adapters/synology/SynologyAdapter.java b/app/src/main/java/org/transdroid/daemon/adapters/synology/SynologyAdapter.java
index ea49facf..45c39888 100644
--- a/app/src/main/java/org/transdroid/daemon/adapters/synology/SynologyAdapter.java
+++ b/app/src/main/java/org/transdroid/daemon/adapters/synology/SynologyAdapter.java
@@ -323,7 +323,7 @@ public class SynologyAdapter implements IDaemonAdapter {
         long downloaded = transfer.getLong("size_downloaded");
         int speed = transfer.getInt("speed_download");
         long size = jsonTorrent.getLong("size");
-        Float eta = Float.valueOf(size - downloaded) / speed;
+        float eta = (float) (size - downloaded) / speed;
         int totalSeeders = 0;
         int totalLeechers = 0;
         if (additional.has("tracker")) {
@@ -349,11 +349,11 @@ public class SynologyAdapter implements IDaemonAdapter {
                 totalSeeders,
                 detail.getInt("connected_leechers"),
                 totalLeechers,
-                eta.intValue(),
+                (int) eta,
                 downloaded,
                 transfer.getLong("size_uploaded"),
                 size,
-                (size == 0) ? 0 : (Float.valueOf(downloaded) / size),
+                (size == 0) ? 0 : ((float) downloaded / size),
                 0,
                 jsonTorrent.getString("title"),
                 new Date(detail.getLong("create_time") * 1000),
diff --git a/app/src/main/java/org/transdroid/daemon/task/SetTransferRatesTask.java b/app/src/main/java/org/transdroid/daemon/task/SetTransferRatesTask.java
index 33c27dbf..5171f599 100644
--- a/app/src/main/java/org/transdroid/daemon/task/SetTransferRatesTask.java
+++ b/app/src/main/java/org/transdroid/daemon/task/SetTransferRatesTask.java
@@ -29,8 +29,8 @@ public class SetTransferRatesTask extends DaemonTask {
 
     public static SetTransferRatesTask create(IDaemonAdapter adapter, Integer uploadRate, Integer downloadRate) {
         Bundle data = new Bundle();
-        data.putInt("UPLOAD_RATE", (uploadRate == null ? -1 : uploadRate.intValue()));
-        data.putInt("DOWNLOAD_RATE", (downloadRate == null ? -1 : downloadRate.intValue()));
+        data.putInt("UPLOAD_RATE", (uploadRate == null ? -1 : uploadRate));
+        data.putInt("DOWNLOAD_RATE", (downloadRate == null ? -1 : downloadRate));
         return new SetTransferRatesTask(adapter, data);
     }
 
diff --git a/app/src/main/java/org/transdroid/daemon/util/SelfSignedTrustManager.java b/app/src/main/java/org/transdroid/daemon/util/SelfSignedTrustManager.java
index d8fc8111..b9eb924b 100644
--- a/app/src/main/java/org/transdroid/daemon/util/SelfSignedTrustManager.java
+++ b/app/src/main/java/org/transdroid/daemon/util/SelfSignedTrustManager.java
@@ -48,7 +48,7 @@ public class SelfSignedTrustManager implements X509TrustManager {
     private static String hexify(byte[] bytes) {
 
         char[] hexDigits = {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f'};
-        StringBuffer buf = new StringBuffer(bytes.length * 2);
+        StringBuilder buf = new StringBuilder(bytes.length * 2);
         for (byte aByte : bytes) {
             buf.append(hexDigits[(aByte & 0xf0) >> 4]);
             buf.append(hexDigits[aByte & 0x0f]);