refactor: address additional Qodana issues (duplicate expressions, re…

…dundant casts, imports)

README.md

@@ -3,6 +3,7 @@
 [![codecov](https://codecov.io/gh/tcheeric/nostr-java/branch/main/graph/badge.svg)](https://codecov.io/gh/tcheeric/nostr-java)
 [![GitHub release](https://img.shields.io/github/v/release/tcheeric/nostr-java)](https://github.com/tcheeric/nostr-java/releases)
 [![License: MIT](https://img.shields.io/badge/License-MIT-yellow.svg)](LICENSE)
+[![Qodana](https://github.com/tcheeric/nostr-java/actions/workflows/qodana_code_quality.yml/badge.svg)](https://github.com/tcheeric/nostr-java/actions/workflows/qodana_code_quality.yml)
 
 `nostr-java` is a Java SDK for the [Nostr](https://github.com/nostr-protocol/nips) protocol. It provides utilities for creating, signing and publishing Nostr events to relays.
 

nostr-java-api/src/main/java/nostr/api/NIP04.java

@@ -16,6 +16,7 @@
 import nostr.encryption.MessageCipher04;
 import nostr.event.BaseTag;
 import nostr.event.impl.GenericEvent;
+import nostr.event.filter.Filterable;
 import nostr.event.tag.GenericTag;
 import nostr.event.tag.PubKeyTag;
 import nostr.id.Identity;
@@ -131,12 +132,10 @@ public static String decrypt(@NonNull Identity rcptId, @NonNull GenericEvent eve
       throw new IllegalArgumentException("Event is not an encrypted direct message");
     }
 
-    var recipient =
-        event.getTags().stream()
-            .filter(t -> t.getCode().equalsIgnoreCase("p"))
+    PubKeyTag pTag =
+        Filterable.getTypeSpecificTags(PubKeyTag.class, event).stream()
             .findFirst()
             .orElseThrow(() -> new NoSuchElementException("No matching p-tag found."));
-    var pTag = (PubKeyTag) recipient;
 
     boolean rcptFlag = amITheRecipient(rcptId, event);
 

nostr-java-crypto/src/main/java/nostr/crypto/bech32/Bech32.java

@@ -253,11 +253,13 @@ private static byte[] convertBits(byte[] data, int fromWidth, int toWidth, boole
         result.add((byte) ((acc >> bits) & ((1 << toWidth) - 1)));
       }
     }
+    int mask = (1 << toWidth) - 1;
     if (pad) {
       if (bits > 0) {
-        result.add((byte) ((acc << (toWidth - bits)) & ((1 << toWidth) - 1)));
+        int partial = (acc << (toWidth - bits)) & mask;
+        result.add((byte) partial);
       }
-    } else if (bits == fromWidth || ((acc << (toWidth - bits)) & ((1 << toWidth) - 1)) != 0) {
+    } else if (bits == fromWidth || ((acc << (toWidth - bits)) & mask) != 0) {
       return null;
     }
     byte[] output = new byte[result.size()];

nostr-java-event/src/main/java/nostr/event/impl/ChannelMessageEvent.java

@@ -24,29 +24,23 @@ public ChannelMessageEvent(PublicKey pubKey, List<BaseTag> baseTags, String cont
   }
 
   public String getChannelCreateEventId() {
-    return getTags().stream()
-        .filter(tag -> "e".equals(tag.getCode()))
-        .map(tag -> (EventTag) tag)
+    return nostr.event.filter.Filterable.getTypeSpecificTags(EventTag.class, this).stream()
         .filter(tag -> tag.getMarker() == Marker.ROOT)
         .map(EventTag::getIdEvent)
         .findFirst()
         .orElseThrow();
   }
 
   public String getChannelMessageReplyEventId() {
-    return getTags().stream()
-        .filter(tag -> "e".equals(tag.getCode()))
-        .map(tag -> (EventTag) tag)
+    return nostr.event.filter.Filterable.getTypeSpecificTags(EventTag.class, this).stream()
         .filter(tag -> tag.getMarker() == Marker.REPLY)
         .map(EventTag::getIdEvent)
         .findFirst()
         .orElse(null);
   }
 
   public Relay getRootRecommendedRelay() {
-    return getTags().stream()
-        .filter(tag -> "e".equals(tag.getCode()))
-        .map(tag -> (EventTag) tag)
+    return nostr.event.filter.Filterable.getTypeSpecificTags(EventTag.class, this).stream()
         .filter(tag -> tag.getMarker() == Marker.ROOT)
         .map(EventTag::getRecommendedRelayUrl)
         .map(Relay::new)
@@ -55,9 +49,7 @@ public Relay getRootRecommendedRelay() {
   }
 
   public Relay getReplyRecommendedRelay(@NonNull String eventId) {
-    return getTags().stream()
-        .filter(tag -> "e".equals(tag.getCode()))
-        .map(tag -> (EventTag) tag)
+    return nostr.event.filter.Filterable.getTypeSpecificTags(EventTag.class, this).stream()
         .filter(tag -> tag.getMarker() == Marker.REPLY && tag.getIdEvent().equals(eventId))
         .map(EventTag::getRecommendedRelayUrl)
         .map(Relay::new)
@@ -70,9 +62,7 @@ public void validate() {
 
     // Check 'e' root - tag
     EventTag rootTag =
-        getTags().stream()
-            .filter(tag -> "e".equals(tag.getCode()))
-            .map(tag -> (EventTag) tag)
+        nostr.event.filter.Filterable.getTypeSpecificTags(EventTag.class, this).stream()
             .filter(tag -> tag.getMarker() == Marker.ROOT)
             .findFirst()
             .orElseThrow(() -> new AssertionError("Missing or invalid `e` root tag."));