core: fix method parameters annotation parsing (fix #57)

jadx-core/src/main/java/jadx/core/dex/attributes/annotations/AnnotationsList.java

@@ -5,12 +5,15 @@ import jadx.core.dex.attributes.IAttribute;
 import jadx.core.utils.Utils;
 
 import java.util.Collection;
+import java.util.Collections;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 
 public class AnnotationsList implements IAttribute {
 
+	public static final AnnotationsList EMPTY = new AnnotationsList(Collections.<Annotation>emptyList());
+
 	private final Map<String, Annotation> map;
 
 	public AnnotationsList(List<Annotation> anList) {

jadx-core/src/main/java/jadx/core/dex/nodes/parser/AnnotationsParser.java

@@ -71,8 +71,14 @@ public class AnnotationsParser {
 	}
 
 	private AnnotationsList readAnnotationSet(int offset) throws DecodeException {
+		if (offset == 0) {
+			return AnnotationsList.EMPTY;
+		}
 		Section section = dex.openSection(offset);
 		int size = section.readInt();
+		if (size == 0) {
+			return AnnotationsList.EMPTY;
+		}
 		List<Annotation> list = new ArrayList<Annotation>(size);
 		for (int i = 0; i < size; i++) {
 			Section anSection = dex.openSection(section.readInt());
@@ -86,7 +92,8 @@ public class AnnotationsParser {
 		EncValueParser parser = new EncValueParser(dex, s);
 		Visibility visibility = null;
 		if (readVisibility) {
-			visibility = VISIBILITIES[s.readByte()];
+			byte v = s.readByte();
+			visibility = VISIBILITIES[v];
 		}
 		int typeIndex = s.readUleb128();
 		int size = s.readUleb128();