diff --git a/src/Helpers/Cache.php b/src/Helpers/Cache.php
index 0678120..6d311ee 100644
--- a/src/Helpers/Cache.php
+++ b/src/Helpers/Cache.php
@@ -4,6 +4,9 @@
 
 namespace DaveLiddament\PhpstanPhpLanguageExtensions\Helpers;
 
+use function array_key_exists;
+use Closure;
+
 /**
  * @template TValue
  */
@@ -12,24 +15,15 @@ class Cache
     /** @var array<string,TValue> */
     private array $cache = [];
 
-    public function hasEntry(string $key): bool
-    {
-        return array_key_exists($key, $this->cache);
-    }
-
-    /** @return TValue */
-    public function getEntry(string $key)
+    /**
+     * @return TValue
+     */
+    public function get(string $key, Closure $initializer): mixed
     {
         if (!array_key_exists($key, $this->cache)) {
-            throw new \LogicException('Call hasEntry first');
+            $this->cache[$key] = $initializer();
         }
 
         return $this->cache[$key];
     }
-
-    /** @param TValue $entry */
-    public function addEntry(string $key, $entry): void
-    {
-        $this->cache[$key] = $entry;
-    }
 }
diff --git a/src/Rules/AbstractFriendRule.php b/src/Rules/AbstractFriendRule.php
index f619a57..4f891b0 100644
--- a/src/Rules/AbstractFriendRule.php
+++ b/src/Rules/AbstractFriendRule.php
@@ -45,26 +45,22 @@ protected function getErrorOrNull(
         $className = $classReflection->getName();
         $fullMethodName = "{$className}::{$methodName}";
 
-        if ($this->cache->hasEntry($fullMethodName)) {
-            $allowedCallingClassesFromMethod = $this->cache->getEntry($fullMethodName);
-        } else {
-            $allowedCallingClassesFromMethod = AttributeValueReader::getAttributeValuesForMethod(
+        $allowedCallingClassesFromMethod = $this->cache->get(
+            $fullMethodName,
+            static fn (): array => AttributeValueReader::getAttributeValuesForMethod(
                 $classReflection->getNativeReflection(),
                 $methodName,
                 Friend::class
-            );
-            $this->cache->addEntry($fullMethodName, $allowedCallingClassesFromMethod);
-        }
+            )
+        );
 
-        if ($this->cache->hasEntry($className)) {
-            $allowedCallingClassesFromClass = $this->cache->getEntry($className);
-        } else {
-            $allowedCallingClassesFromClass = AttributeValueReader::getAttributeValuesForClass(
+        $allowedCallingClassesFromClass = $this->cache->get(
+            $className,
+            static fn (): array => AttributeValueReader::getAttributeValuesForClass(
                 $classReflection->getNativeReflection(),
                 Friend::class
-            );
-            $this->cache->addEntry($className, $allowedCallingClassesFromClass);
-        }
+            )
+        );
 
         $allowedCallingClasses = array_merge($allowedCallingClassesFromClass, $allowedCallingClassesFromMethod);
 
diff --git a/src/Rules/AbstractPackageRule.php b/src/Rules/AbstractPackageRule.php
index bdda039..e457416 100644
--- a/src/Rules/AbstractPackageRule.php
+++ b/src/Rules/AbstractPackageRule.php
@@ -4,6 +4,7 @@
 
 namespace DaveLiddament\PhpstanPhpLanguageExtensions\Rules;
 
+use function count;
 use DaveLiddament\PhpLanguageExtensions\Package;
 use DaveLiddament\PhpstanPhpLanguageExtensions\Config\TestConfig;
 use DaveLiddament\PhpstanPhpLanguageExtensions\Helpers\Cache;
@@ -45,24 +46,16 @@ protected function getErrorOrNull(
 
         $fullMethodName = "{$className}::{$methodName}";
 
-        if ($this->cache->hasEntry($fullMethodName)) {
-            $isMethodPackageLevel = $this->cache->getEntry($fullMethodName);
-        } else {
-            if ($nativeReflection->hasMethod($methodName)) {
-                $methodReflection = $nativeReflection->getMethod($methodName);
-                $isMethodPackageLevel = count($methodReflection->getAttributes(Package::class)) > 0;
-            } else {
-                $isMethodPackageLevel = false;
-            }
-            $this->cache->addEntry($fullMethodName, $isMethodPackageLevel);
-        }
+        $isMethodPackageLevel = $this->cache->get(
+            $fullMethodName,
+            static fn (): bool => $nativeReflection->hasMethod($methodName)
+                && count($nativeReflection->getMethod($methodName)->getAttributes(Package::class)) > 0
+        );
 
-        if ($this->cache->hasEntry($className)) {
-            $isClassPackageLevel = $this->cache->getEntry($className);
-        } else {
-            $isClassPackageLevel = count($nativeReflection->getAttributes(Package::class)) > 0;
-            $this->cache->addEntry($className, $isClassPackageLevel);
-        }
+        $isClassPackageLevel = $this->cache->get(
+            $className,
+            static fn (): bool => count($nativeReflection->getAttributes(Package::class)) > 0
+        );
 
         $isPackageLevel = $isClassPackageLevel || $isMethodPackageLevel;
 
diff --git a/src/Rules/AbstractTestTagRule.php b/src/Rules/AbstractTestTagRule.php
index 85e5bee..76b86dc 100644
--- a/src/Rules/AbstractTestTagRule.php
+++ b/src/Rules/AbstractTestTagRule.php
@@ -4,6 +4,7 @@
 
 namespace DaveLiddament\PhpstanPhpLanguageExtensions\Rules;
 
+use function count;
 use DaveLiddament\PhpLanguageExtensions\TestTag;
 use DaveLiddament\PhpstanPhpLanguageExtensions\Config\TestConfig;
 use DaveLiddament\PhpstanPhpLanguageExtensions\Helpers\Cache;
@@ -45,17 +46,11 @@ protected function getErrorOrNull(
 
         $fullMethodName = "{$className}::{$methodName}";
 
-        if ($this->cache->hasEntry($fullMethodName)) {
-            $isTestTag = $this->cache->getEntry($fullMethodName);
-        } else {
-            if ($nativeReflection->hasMethod($methodName)) {
-                $methodReflection = $nativeReflection->getMethod($methodName);
-                $isTestTag = count($methodReflection->getAttributes(TestTag::class)) > 0;
-            } else {
-                $isTestTag = false;
-            }
-            $this->cache->addEntry($fullMethodName, $isTestTag);
-        }
+        $isTestTag = $this->cache->get(
+            $fullMethodName,
+            static fn (): bool => $nativeReflection->hasMethod($methodName)
+                && count($nativeReflection->getMethod($methodName)->getAttributes(TestTag::class)) > 0
+        );
 
         if (!$isTestTag) {
             return null;
diff --git a/src/Rules/InjectableVersionRule.php b/src/Rules/InjectableVersionRule.php
index e15b331..0805b1c 100644
--- a/src/Rules/InjectableVersionRule.php
+++ b/src/Rules/InjectableVersionRule.php
@@ -73,12 +73,7 @@ public function processNode(Node $node, Scope $scope): array
                 : $type->getReferencedClasses();
 
             foreach ($classesToCheck as $className) {
-                if ($this->cache->hasEntry($className)) {
-                    $classToUse = $this->cache->getEntry($className);
-                } else {
-                    $classToUse = $this->checkClass($className);
-                    $this->cache->addEntry($className, $classToUse);
-                }
+                $classToUse = $this->cache->get($className, fn () => $this->checkClass($className));
 
                 if (null !== $classToUse) {
                     $message = sprintf(
diff --git a/tests/Unit/CacheTest.php b/tests/Unit/CacheTest.php
index c40b37c..a92708c 100644
--- a/tests/Unit/CacheTest.php
+++ b/tests/Unit/CacheTest.php
@@ -22,21 +22,20 @@ protected function setup(): void
         $this->cache = new Cache();
     }
 
-    public function testEmptyCache(): void
+    public function testEntriesShouldOnlyBeInitializedOnce(): void
     {
-        $this->assertFalse($this->cache->hasEntry(self::ENTRY_1));
-    }
+        $initializationCount = 0;
 
-    public function testAddValueToCache(): void
-    {
-        $this->cache->addEntry(self::ENTRY_1, self::VALUE_1);
-        $this->assertTrue($this->cache->hasEntry(self::ENTRY_1));
-        $this->assertSame(self::VALUE_1, $this->cache->getEntry(self::ENTRY_1));
-    }
+        $initializer = static function () use (&$initializationCount): string {
+            ++$initializationCount;
 
-    public function testAccessMissingEntry(): void
-    {
-        $this->expectException(\LogicException::class);
-        $this->cache->getEntry(self::ENTRY_1);
+            return self::VALUE_1;
+        };
+
+        self::assertSame(self::VALUE_1, $this->cache->get(self::ENTRY_1, $initializer));
+        self::assertSame(1, $initializationCount);
+
+        self::assertSame(self::VALUE_1, $this->cache->get(self::ENTRY_1, $initializer));
+        self::assertSame(1, $initializationCount);
     }
 }