fix(gui): add synchronization to SimpleIndex class (#435)

jadx-gui/src/main/java/jadx/gui/ui/SearchDialog.java

@@ -176,6 +176,7 @@ public class SearchDialog extends CommonSearchDialog {
 				.subscribeOn(Schedulers.single())
 				.doOnNext(r -> LOG.debug("search event: {}", r))
 				.switchMap(text -> prepareSearch(text)
+						.doOnError(e -> LOG.error("Error prepare search: {}", e.getMessage(), e))
 						.subscribeOn(Schedulers.single())
 						.toList()
 						.toFlowable(), 1)

jadx-gui/src/main/java/jadx/gui/utils/search/SimpleIndex.java

@@ -12,11 +12,15 @@ public class SimpleIndex<T> implements SearchIndex<T> {
 	private final List<String> keys = new ArrayList<>();
 	private final List<T> values = new ArrayList<>();
 
+	private final Object syncData = new Object();
+
 	@Override
 	public void put(String str, T value) {
+		synchronized (syncData) {
 			keys.add(str);
 			values.add(value);
 		}
+	}
 
 	@Override
 	public void put(StringRef str, T value) {
@@ -39,7 +43,8 @@ public class SimpleIndex<T> implements SearchIndex<T> {
 	@Override
 	public Flowable<T> search(final String searchStr, final boolean caseInsensitive) {
 		return Flowable.create(emitter -> {
-			int size = size();
+			synchronized (syncData) {
+				int size = keys.size();
 				for (int i = 0; i < size; i++) {
 					if (isMatched(keys.get(i), searchStr, caseInsensitive)) {
 						emitter.onNext(values.get(i));
@@ -48,12 +53,15 @@ public class SimpleIndex<T> implements SearchIndex<T> {
 						return;
 					}
 				}
+			}
 			emitter.onComplete();
 		}, BackpressureStrategy.LATEST);
 	}
 
 	@Override
 	public int size() {
+		synchronized (syncData) {
 			return keys.size();
 		}
+	}
 }