Fixed issue with Placeholders displaying blank values

Hopefully fixed permission exception
Bump dependency versions

pom.xml

@@ -91,7 +91,7 @@
 		<dependency>
 			<groupId>me.clip</groupId>
 			<artifactId>placeholderapi</artifactId>
-			<version>2.11.3</version>
+			<version>2.11.5</version>
 			<scope>provided</scope>
 		</dependency>
 		<!-- Bountiful API -->
@@ -138,7 +138,7 @@
 		<dependency>
 			<groupId>com.github.cryptomorin</groupId>
 			<artifactId>XSeries</artifactId>
-			<version>9.5.0</version>
+			<version>9.8.0</version>
 			<scope>compile</scope>
 		</dependency>
 		<!-- Version Compare -->
@@ -152,7 +152,7 @@
 		<dependency>
 			<groupId>com.github.simplix-softworks</groupId>
 			<artifactId>simplixstorage</artifactId>
-			<version>3.2.6</version>
+			<version>3.2.7</version>
 		</dependency>
 		<!-- Update to remove known vulnerabilities -->
 		<dependency>
@@ -187,7 +187,7 @@
 			<plugin>
 				<groupId>org.apache.maven.plugins</groupId>
 				<artifactId>maven-compiler-plugin</artifactId>
-				<version>3.11.0</version>
+				<version>3.12.0</version>
 				<configuration>
 					<source>${java.version}</source>
 					<target>${java.version}</target>
@@ -206,7 +206,7 @@
 			<plugin>
 				<groupId>org.apache.maven.plugins</groupId>
 				<artifactId>maven-shade-plugin</artifactId>
-				<version>3.5.0</version>
+				<version>3.5.1</version>
 				<configuration>
 					<createDependencyReducedPom>false</createDependencyReducedPom>
 					<minimizeJar>true</minimizeJar>
@@ -280,7 +280,7 @@
 			<plugin>
 				<groupId>org.apache.maven.plugins</groupId>
 				<artifactId>maven-checkstyle-plugin</artifactId>
-				<version>3.3.0</version>
+				<version>3.3.1</version>
 				<configuration>
 					<configLocation>src/main/resources/parkourCheckstyles.xml</configLocation>
 					<consoleOutput>true</consoleOutput>
@@ -291,7 +291,7 @@
 					<dependency>
 						<groupId>com.puppycrawl.tools</groupId>
 						<artifactId>checkstyle</artifactId>
-						<version>10.9.1</version>
+						<version>10.12.6</version>
 					</dependency>
 				</dependencies>
 				<executions>

src/main/java/io/github/a5h73y/parkour/ParkourPlaceholders.java

@@ -568,11 +568,7 @@ private String getCheckpointHologramMessage(ParkourSession session, String cours
     private String getOrRetrieveCache(Supplier<String> callback, String... keys) {
         String key = generateCacheKey(keys);
         // check if the key exists or its 'get' is about to expire.
-        if (!cache.containsKey(key) || cache.get(key).isEmpty()) {
-            cache.put(key, callback.get());
-        }
-
-        return cache.get(key).orElse(NO_TIME_RECORDED);
+        return cache.computeIfAbsent(key, k -> cache.createCacheValue(callback.get()));
     }
 
     private String getTimeValue(long milliseconds) {

src/main/java/io/github/a5h73y/parkour/type/player/session/ParkourSessionConfig.java

@@ -37,7 +37,8 @@ public static File getPlayerParkourSessionFile(OfflinePlayer player, String cour
     }
 
     public static boolean hasParkourSessionConfig(OfflinePlayer player, String courseName) {
-        return getPlayerParkourSessionFile(player, courseName).exists();
+        File file = getPlayerParkourSessionFile(player, courseName);
+        return file.exists() && file.canWrite();
     }
 
     public static ParkourSessionConfig getConfig(OfflinePlayer player, String courseName) {

src/main/java/io/github/a5h73y/parkour/utility/cache/GenericCache.java

@@ -6,6 +6,7 @@
 import java.util.Set;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.ConcurrentMap;
+import java.util.function.Function;
 import java.util.stream.Collectors;
 
 /**
@@ -78,7 +79,11 @@ public void put(K key, V value) {
         this.cacheMap.put(key, this.createCacheValue(value));
     }
 
-    protected CacheValue<V> createCacheValue(V value) {
+    public V computeIfAbsent(K key, Function<K, CacheValue<V>> boop) {
+        return this.cacheMap.computeIfAbsent(key, boop).getValue();
+    }
+
+    public CacheValue<V> createCacheValue(V value) {
         LocalDateTime now = LocalDateTime.now();
         return new CacheValue<>() {
             @Override