diff --git a/app/src/main/java/org/fdroid/fdroid/AppFilter.java b/app/src/main/java/org/fdroid/fdroid/AppFilter.java
index e139ae808..ee3397b02 100644
--- a/app/src/main/java/org/fdroid/fdroid/AppFilter.java
+++ b/app/src/main/java/org/fdroid/fdroid/AppFilter.java
@@ -29,12 +29,8 @@ public class AppFilter {
             return false;
         }
 
-        if (!Preferences.get().filterAppsRequiringRoot() &&
-                app.requirements.contains("root")) {
-            return true;
-        }
-
-        return false;
+        return !Preferences.get().filterAppsRequiringRoot()
+                && app.requirements.contains("root");
     }
 
 }
diff --git a/app/src/main/java/org/fdroid/fdroid/net/WifiStateChangeService.java b/app/src/main/java/org/fdroid/fdroid/net/WifiStateChangeService.java
index 7b13d1683..160ca6197 100644
--- a/app/src/main/java/org/fdroid/fdroid/net/WifiStateChangeService.java
+++ b/app/src/main/java/org/fdroid/fdroid/net/WifiStateChangeService.java
@@ -219,7 +219,7 @@ public class WifiStateChangeService extends Service {
                             if (inetAddress.equals(address.getAddress()) && !TextUtils.isEmpty(FDroidApp.ipAddressString)) {
                                 String cidr = String.format(Locale.ENGLISH, "%s/%d",
                                         FDroidApp.ipAddressString, address.getNetworkPrefixLength());
-                                FDroidApp.subnetInfo = (new SubnetUtils(cidr)).getInfo();
+                                FDroidApp.subnetInfo = new SubnetUtils(cidr).getInfo();
                                 break;
                             }
                         }
diff --git a/config/pmd/rules.xml b/config/pmd/rules.xml
index 34775e15e..242403a32 100644
--- a/config/pmd/rules.xml
+++ b/config/pmd/rules.xml
@@ -17,7 +17,19 @@
     </rule>
     <rule ref="rulesets/java/optimizations.xml/PrematureDeclaration"/>
     <rule ref="rulesets/java/optimizations.xml/AddEmptyString"/>
+    <rule ref="rulesets/java/optimizations.xml/UseArraysAsList"/>
+
     <rule ref="rulesets/java/controversial.xml/UnnecessaryConstructor"/>
+    <rule ref="rulesets/java/controversial.xml/UnnecessaryParentheses"/>
+
+    <rule ref="rulesets/java/strictexception.xml/AvoidRethrowingException"/>
+    <rule ref="rulesets/java/strictexception.xml/AvoidCatchingThrowable"/>
+    <rule ref="rulesets/java/strictexception.xml/AvoidCatchingNPE"/>
+    <rule ref="rulesets/java/strictexception.xml/DoNotExtendJavaLangError"/>
+    <rule ref="rulesets/java/strictexception.xml/DoNotThrowExceptionInFinally"/>
+    <rule ref="rulesets/java/strictexception.xml/AvoidThrowingNewInstanceOfSameException"/>
+    <rule ref="rulesets/java/strictexception.xml/AvoidThrowingNullPointerException"/>
+
     <rule ref="rulesets/java/design.xml/FinalFieldCouldBeStatic"/>
     <rule ref="rulesets/java/design.xml/CloseResource"/>
     <rule ref="rulesets/java/design.xml/DefaultLabelNotLastInSwitchStmt"/>
@@ -27,4 +39,8 @@
     <rule ref="rulesets/java/design.xml/IdempotentOperations"/>
     <rule ref="rulesets/java/design.xml/ImmutableField"/>
     <rule ref="rulesets/java/design.xml/SingularField"/>
+    <rule ref="rulesets/java/design.xml/SimplifyBooleanReturns"/>
+    <rule ref="rulesets/java/design.xml/SimplifyBooleanExpressions"/>
+    <rule ref="rulesets/java/design.xml/LogicInversion"/>
+
 </ruleset>