style: allow underscores in catch parameter naming and use _ for unused exceptions

Author: ChernyavckiiPavlo

checkstyle.xml

@@ -178,7 +178,7 @@
                      value="Lambda parameter name ''{0}'' must match pattern ''{1}''."/>
         </module>
         <module name="CatchParameterName">
-            <property name="format" value="^[a-z]([a-z0-9][a-zA-Z0-9]*)?$"/>
+            <property name="format" value="^(_|[a-z]([a-z0-9][a-zA-Z0-9]*)?)$"/>
             <message key="name.invalidPattern"
                      value="Catch parameter name ''{0}'' must match pattern ''{1}''."/>
         </module>

src/main/java/com/itasocialacademy/oitassist/logfile/dao/FileSystemLogFileDao.java

@@ -63,7 +63,7 @@ public Optional<Path> downloadFile(String fileName) {
                 return Optional.empty();
             }
             return Optional.of(filePath);
-        } catch (NoSuchFileException exception) {
+        } catch (NoSuchFileException _) {
             log.debug("Log file not found for download: {}", fileName);
 
             return Optional.empty();
@@ -86,7 +86,7 @@ private Path resolveDownloadPath(String fileName) {
             }
 
             return filePath;
-        } catch (InvalidPathException exception) {
+        } catch (InvalidPathException _) {
             throw new InvalidLogFileNameException();
         }
     }

src/main/java/com/itasocialacademy/oitassist/logfile/service/LogFileServiceImpl.java

@@ -122,7 +122,7 @@ private Resource createDownloadResource(Path filePath) {
                     LinkOption.NOFOLLOW_LINKS);
 
             return new InputStreamResource(inputStream, "Log file " + filePath.getFileName());
-        } catch (NoSuchFileException exception) {
+        } catch (NoSuchFileException _) {
             throw new LogFileNotFoundException(filePath.getFileName().toString());
         } catch (IOException | SecurityException exception) {
             log.error("Failed to open log file for download: {}", filePath, exception);