diff --git a/pom.xml b/pom.xml
index e461d95..0492111 100644
--- a/pom.xml
+++ b/pom.xml
@@ -14,6 +14,8 @@
         <lwjgl.natives>natives-windows</lwjgl.natives>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
         <java.version>1.8</java.version>
+        <maven.compiler.source>11</maven.compiler.source>
+        <maven.compiler.target>11</maven.compiler.target>
     </properties>
 
     <build>
@@ -24,6 +26,7 @@
                 <configuration>
                     <source>11.0</source>
                     <target>11.0</target>
+
                 </configuration>
             </plugin>
         </plugins>
diff --git a/src/main/java/resources/Acceleration.java b/src/main/java/resources/Acceleration.java
index 69f1a18..c31e238 100644
--- a/src/main/java/resources/Acceleration.java
+++ b/src/main/java/resources/Acceleration.java
@@ -36,7 +36,7 @@
         this.onground = onground;
     }
 
-    public Pair getValue() {
+    public Pair<Double> getValue() {
         return value;
     }
 }
\ No newline at end of file
diff --git a/src/main/java/resources/Clear.java b/src/main/java/resources/Clear.java
index da506e7..2325d12 100644
--- a/src/main/java/resources/Clear.java
+++ b/src/main/java/resources/Clear.java
@@ -9,7 +9,7 @@
 
     public boolean getClear() {
         boolean temp_l4;
-        if (((Double)this.position.getValue().getFirst() > 100.0)) {
+        if ((this.position.getValue().getFirst() > 100.0)) {
             temp_l4 = true;
         } else {
             temp_l4 = false;
diff --git a/src/main/java/resources/Gameover.java b/src/main/java/resources/Gameover.java
index 4d3bdba..2bdcac7 100644
--- a/src/main/java/resources/Gameover.java
+++ b/src/main/java/resources/Gameover.java
@@ -9,7 +9,7 @@
 
     public boolean getGameover() {
         boolean temp_l6;
-        if (((Double)this.position.getValue().getSecond() < -(1.0))) {
+        if ((this.position.getValue().getSecond() < -(1.0))) {
             temp_l6 = true;
         } else {
             temp_l6 = false;
diff --git a/src/main/java/resources/Onground.java b/src/main/java/resources/Onground.java
index 3b5fa82..5e60ef5 100644
--- a/src/main/java/resources/Onground.java
+++ b/src/main/java/resources/Onground.java
@@ -10,5 +10,5 @@
     }
 
     public boolean getOnground() {
-        return ((this.ground.getValue() == true) && ((Double)this.position.getValue().getSecond() <= 0.0));    }
+        return ((this.ground.getValue() == true) && (this.position.getValue().getSecond() <= 0.0));    }
 }
\ No newline at end of file
diff --git a/src/main/java/resources/Position.java b/src/main/java/resources/Position.java
index 9d59e22..e79f7a9 100644
--- a/src/main/java/resources/Position.java
+++ b/src/main/java/resources/Position.java
@@ -18,7 +18,7 @@
         this.ground = ground;
     }
 
-    public Pair getValue() {
+    public Pair<Double> getValue() {
         return value;
     }
 }
\ No newline at end of file