fix(gui): resolve cast exception for variable reference (#1489)

jadx-core/src/main/java/jadx/api/JadxDecompiler.java

@@ -683,10 +683,13 @@ public final class JadxDecompiler implements Closeable {
 			throw new JadxRuntimeException("Missing code info for resolve VarRef: " + varRef);
 		}
 		ICodeAnnotation varNodeAnn = codeInfo.getCodeMetadata().getAt(varRef.getRefPos());
-		if (varNodeAnn == null) {
-			return null;
+		if (varNodeAnn != null && varNodeAnn.getAnnType() == ICodeAnnotation.AnnType.DECLARATION) {
+			ICodeNodeRef nodeRef = ((NodeDeclareRef) varNodeAnn).getNode();
+			if (nodeRef.getAnnType() == ICodeAnnotation.AnnType.VAR) {
+				return resolveVarNode((VarNode) nodeRef);
+			}
 		}
-		return (JavaVariable) getJavaNodeByCodeAnnotation(codeInfo, varNodeAnn);
+		return null;
 	}
 
 	List<JavaNode> convertNodes(Collection<? extends ICodeNodeRef> nodesList) {

jadx-core/src/main/java/jadx/api/JavaClass.java

@@ -6,12 +6,16 @@ import java.util.Comparator;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.Objects;
 
 import org.jetbrains.annotations.ApiStatus;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 import jadx.api.metadata.ICodeAnnotation;
+import jadx.api.metadata.ICodeAnnotation.AnnType;
 import jadx.api.metadata.ICodeNodeRef;
 import jadx.core.dex.attributes.AFlag;
 import jadx.core.dex.attributes.AType;
@@ -22,6 +26,7 @@ import jadx.core.dex.nodes.FieldNode;
 import jadx.core.dex.nodes.MethodNode;
 
 public final class JavaClass implements JavaNode {
+	private static final Logger LOG = LoggerFactory.getLogger(JavaClass.class);
 
 	private final JadxDecompiler decompiler;
 	private final ClassNode cls;
@@ -196,12 +201,17 @@ public final class JavaClass implements JavaNode {
 		List<Integer> result = new ArrayList<>();
 		for (Map.Entry<Integer, ICodeAnnotation> entry : map.entrySet()) {
 			ICodeAnnotation ann = entry.getValue();
-			if (ann.getAnnType() == ICodeAnnotation.AnnType.DECLARATION) {
-				// ignore declarations
+			AnnType annType = ann.getAnnType();
+			if (annType == AnnType.DECLARATION || annType == AnnType.OFFSET) {
+				// ignore declarations and offset annotations
 				continue;
 			}
+			// ignore declarations
 			JavaNode annNode = rootDec.getJavaNodeByCodeAnnotation(codeInfo, ann);
-			if (javaNode.equals(annNode)) {
+			if (annNode == null && LOG.isDebugEnabled()) {
+				LOG.debug("Failed to resolve code annotation, cls: {}, pos: {}, ann: {}", this, entry.getKey(), ann);
+			}
+			if (Objects.equals(annNode, javaNode)) {
 				result.add(entry.getKey());
 			}
 		}

jadx-gui/src/main/java/jadx/gui/ui/dialog/UsageDialog.java

@@ -100,10 +100,6 @@ public class UsageDialog extends CommonSearchDialog {
 		JadxDecompiler decompiler = mainWindow.getWrapper().getDecompiler();
 		List<Integer> usePositions = topUseClass.getUsePlacesFor(codeInfo, searchNode);
 		for (int pos : usePositions) {
-			if (searchNode.getTopParentClass().equals(topUseClass) && pos == searchNode.getDefPos()) {
-				// skip declaration
-				continue;
-			}
 			String line = CodeUtils.getLineForPos(code, pos);
 			if (line.startsWith("import ")) {
 				continue;

jadx-gui/src/main/java/jadx/gui/utils/codecache/disk/DiskCodeCache.java

@@ -37,7 +37,7 @@ import jadx.core.utils.files.FileUtils;
 public class DiskCodeCache implements ICodeCache {
 	private static final Logger LOG = LoggerFactory.getLogger(DiskCodeCache.class);
 
-	private static final int DATA_FORMAT_VERSION = 7;
+	private static final int DATA_FORMAT_VERSION = 8;
 
 	private final Path srcDir;
 	private final Path metaDir;

jadx-gui/src/main/java/jadx/gui/utils/codecache/disk/adapters/VarRefAdapter.java

@@ -13,14 +13,14 @@ public class VarRefAdapter extends BaseDataAdapter<VarRef> {
 	@Override
 	public void write(DataOutput out, VarRef value) throws IOException {
 		int refPos = value.getRefPos();
-		if (refPos == 0) {
-			throw new RuntimeException("Variable refPos is zero: " + value);
+		if (refPos <= 0) {
+			throw new RuntimeException("Variable refPos is invalid: " + value);
 		}
-		out.writeShort(refPos);
+		out.writeInt(refPos);
 	}
 
 	@Override
 	public VarRef read(DataInput in) throws IOException {
-		return VarRef.fromPos(in.readShort());
+		return VarRef.fromPos(in.readInt());
 	}
 }