download: improved images download from scryfall source:

- fixed wrong timeouts for api (fixed 429 Too Many Requests);
- added any/10 parallel threads support;
- current api limit is 1 request per 300 ms;

Mage.Client/src/main/java/mage/client/components/ability/AbilityPicker.java

@@ -331,7 +331,7 @@ public class AbilityPicker extends JXPanel implements MouseWheelListener {
                     wait();
                 }
             }
-        } catch (InterruptedException ignored) {
+        } catch (InterruptedException ignore) {
         }
 
     }

Mage.Client/src/main/java/org/mage/card/arcane/Util.java

@@ -68,7 +68,7 @@ public final class Util {
     public static void sleep(int millis) {
         try {
             TimeUnit.MILLISECONDS.sleep(millis);
-        } catch (InterruptedException ignored) {
+        } catch (InterruptedException ignore) {
         }
     }
 

Mage.Client/src/main/java/org/mage/plugins/card/dl/sources/ScryfallImageSource.java

@@ -13,8 +13,8 @@ import org.mage.plugins.card.images.CardDownloadData;
 
 import java.io.InputStream;
 import java.io.InputStreamReader;
-import java.net.Proxy;
 import java.util.*;
+import java.util.concurrent.locks.ReentrantLock;
 
 /**
  * @author JayDi85
@@ -28,7 +28,9 @@ public class ScryfallImageSource implements CardImageSource {
     private final Map<CardLanguage, String> languageAliases;
     private CardLanguage currentLanguage = CardLanguage.ENGLISH; // working language
     private final Map<CardDownloadData, String> preparedUrls = new HashMap<>();
-    private static final int DOWNLOAD_TIMEOUT_MS = 100;
+
+    private static final ReentrantLock waitBeforeRequestLock = new ReentrantLock();
+    private static final int DOWNLOAD_TIMEOUT_MS = 300;
 
     public static ScryfallImageSource getInstance() {
         return instance;
@@ -330,15 +332,22 @@ public class ScryfallImageSource implements CardImageSource {
 
     @Override
     public void doPause(String fullUrl) {
+        // scryfall recommends 300 ms timeout per each request to API to work under a rate limit
+        // possible error: 429 Too Many Requests
+        // TODO: add diff endpoint supports (api calls with timeout, cdn/direct calls without timeout)
         waitBeforeRequest();
     }
 
     private void waitBeforeRequest() {
-        // scryfall recommends 50-100 ms timeout per each request to API to work under a rate limit
-        // possible error: 429 Too Many Requests
         try {
-            Thread.sleep(DOWNLOAD_TIMEOUT_MS);
-        } catch (InterruptedException ignored) {
+            // single wait queue for all threads - it's guarantee min timeout before each api call
+            waitBeforeRequestLock.lock();
+            try {
+                Thread.sleep(DOWNLOAD_TIMEOUT_MS);
+            } finally {
+                waitBeforeRequestLock.unlock();
+            }
+        } catch (InterruptedException ignore) {
         }
     }
 

Mage/src/main/java/mage/cards/decks/importer/CardLookup.java

@@ -52,7 +52,7 @@ public class CardLookup {
             if (result.isPresent()) {
                 return result;
             }
-        } catch (NumberFormatException ignored) {
+        } catch (NumberFormatException ignore) {
             /* ignored */
         }
 

Mage/src/main/java/mage/util/ThreadUtils.java

@@ -51,7 +51,7 @@ public final class ThreadUtils {
     public static void sleep(int millis) {
         try {
             Thread.sleep(millis);
-        } catch (InterruptedException ignored) {
+        } catch (InterruptedException ignore) {
         }
     }