chore: Small refactorings to improves readability and maintainability

Author: en-milie

src/main/java/com/endava/cats/args/FilterArguments.java

@@ -325,7 +325,7 @@ public List<String> getFirstPhaseFuzzersForPath() {
 
             fuzzersToBeRun = fuzzersToBeRun.stream()
                     .filter(fuzzer -> !secondPhaseFuzzers.contains(fuzzer))
-                    .collect(Collectors.toList());
+                    .toList();
         }
 
         return fuzzersToBeRun;
@@ -420,7 +420,7 @@ private List<String> constructFuzzersListFromCheckArguments() {
         finalList.addAll(this.filterFuzzersByAnnotationWhenCheckArgumentSupplied(checkArguments.isCheckHttp(), HttpFuzzer.class));
 
         if (finalList.isEmpty()) {
-            finalList = fuzzers.stream().map(Object::toString).collect(Collectors.toList());
+            finalList = fuzzers.stream().map(Object::toString).toList();
         }
 
         this.removeIfNotSupplied(checkArguments.isIncludeControlChars(), ControlCharFuzzer.class, finalList);

src/main/java/com/endava/cats/generator/simple/StringGenerator.java

@@ -284,54 +284,46 @@ public static String cleanPattern(String pattern) {
     }
 
     private static String removeMisplacedDollarSigns(String regex) {
-        StringBuilder result = new StringBuilder();
+        StringBuilder result = new StringBuilder(regex.length());
         boolean inCharClass = false;
-        boolean escapeNext = false;
-        int parenDepth = 0; // Tracks depth of parentheses
+        int parenDepth = 0;
         int length = regex.length();
 
         for (int i = 0; i < length; i++) {
             char c = regex.charAt(i);
 
-            if (escapeNext) {
-                // Current character is escaped; add it and reset escape flag
-                result.append(c);
-                escapeNext = false;
-            } else if (c == '\\') {
-                // Next character is escaped
-                result.append(c);
-                escapeNext = true;
-            } else if (c == '[') {
-                // Entering character class
-                result.append(c);
-                inCharClass = true;
-            } else if (c == ']') {
-                // Exiting character class
-                result.append(c);
-                inCharClass = false;
-            } else if (c == '(') {
-                // Entering parentheses group
-                result.append(c);
-                parenDepth++;
-            } else if (c == ')') {
-                // Exiting parentheses group
-                result.append(c);
-                if (parenDepth > 0) {
-                    parenDepth--;
-                }
-            } else if (c == '$') {
-                if (i == length - 1) {
-                    // Dollar sign at the end; keep it
+            switch (c) {
+                case '\\':
                     result.append(c);
-                } else if (inCharClass) {
-                    // Dollar sign inside character class; keep it
+                    if (i + 1 < length) {
+                        result.append(regex.charAt(++i));
+                    }
+                    break;
+                case '[':
+                    inCharClass = true;
                     result.append(c);
-                } else if (parenDepth > 0) {
-                    // Dollar sign inside parentheses; keep it
+                    break;
+                case ']':
+                    inCharClass = false;
+                    result.append(c);
+                    break;
+                case '(':
+                    parenDepth++;
+                    result.append(c);
+                    break;
+                case ')':
+                    if (parenDepth > 0) {
+                        parenDepth--;
+                    }
+                    result.append(c);
+                    break;
+                case '$':
+                    if (i == length - 1 || inCharClass || parenDepth > 0) {
+                        result.append(c);
+                    }
+                    break;
+                default:
                     result.append(c);
-                }
-            } else {
-                result.append(c);
             }
         }
         return result.toString();

src/main/java/com/endava/cats/model/generator/OpenAPIModelGenerator.java

@@ -431,7 +431,7 @@ int getArrayLength(Schema<?> property) {
         int min = null == property.getMinItems() ? 1 : property.getMinItems();
         int max = null == property.getMaxItems() ? 2 : property.getMaxItems();
 
-        return Math.max(min, Math.min(this.arraySize, max));
+        return Math.clamp(this.arraySize, min, max);
     }
 
     double randomNumber(Double min, Double max) {

src/main/java/com/endava/cats/util/DepthLimitingSerializer.java

@@ -16,7 +16,7 @@
  * to exceed the maximum size that Jackson can serialize without streaming.
  */
 public class DepthLimitingSerializer extends JsonSerializer<Object> {
-    private static int maxDepth;
+    private final int maxDepth;
     private final ObjectMapper mapper = new ObjectMapper();
     private final ThreadLocal<Integer> currentDepth = ThreadLocal.withInitial(() -> 0);