core: fix enum processing order, remove synchronization (#257)

jadx-core/src/main/java/jadx/core/dex/attributes/nodes/EnumMapAttr.java

 package jadx.core.dex.attributes.nodes;
 
+import java.util.HashMap;
+import java.util.Map;
+
+import org.jetbrains.annotations.Nullable;
+
 import jadx.core.dex.attributes.AType;
 import jadx.core.dex.attributes.IAttribute;
 import jadx.core.dex.nodes.FieldNode;
 
-import java.util.HashMap;
-import java.util.Map;
-
 public class EnumMapAttr implements IAttribute {
 
 	public static class KeyValueMap {
@@ -21,9 +23,14 @@ public class EnumMapAttr implements IAttribute {
 		}
 	}
 
-	private final Map<FieldNode, KeyValueMap> fieldsMap = new HashMap<>();
+	@Nullable
+	private Map<FieldNode, KeyValueMap> fieldsMap;
 
+	@Nullable
 	public KeyValueMap getMap(FieldNode field) {
+		if (fieldsMap == null) {
+			return null;
+		}
 		return fieldsMap.get(field);
 	}
 
@@ -31,11 +38,18 @@ public class EnumMapAttr implements IAttribute {
 		KeyValueMap map = getMap(field);
 		if (map == null) {
 			map = new KeyValueMap();
+			if (fieldsMap == null) {
+				fieldsMap = new HashMap<>();
+			}
 			fieldsMap.put(field, map);
 		}
 		map.put(key, value);
 	}
 
+	public boolean isEmpty() {
+		return fieldsMap == null || fieldsMap.isEmpty();
+	}
+
 	@Override
 	public AType<EnumMapAttr> getType() {
 		return AType.ENUM_MAP;
@@ -45,5 +59,4 @@ public class EnumMapAttr implements IAttribute {
 	public String toString() {
 		return "Enum fields map: " + fieldsMap;
 	}
-
 }

jadx-core/src/main/java/jadx/core/dex/visitors/ReSugarCode.java

 package jadx.core.dex.visitors;
 
-import jadx.core.ProcessClass;
+import java.util.List;
+
+import org.jetbrains.annotations.Nullable;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
 import jadx.core.dex.attributes.AFlag;
 import jadx.core.dex.attributes.AType;
 import jadx.core.dex.attributes.nodes.EnumMapAttr;
@@ -18,18 +23,13 @@ import jadx.core.dex.instructions.args.InsnWrapArg;
 import jadx.core.dex.instructions.args.LiteralArg;
 import jadx.core.dex.nodes.BlockNode;
 import jadx.core.dex.nodes.ClassNode;
+import jadx.core.dex.nodes.DexNode;
 import jadx.core.dex.nodes.FieldNode;
 import jadx.core.dex.nodes.InsnNode;
 import jadx.core.dex.nodes.MethodNode;
 import jadx.core.utils.InstructionRemover;
-import jadx.core.utils.exceptions.DecodeException;
 import jadx.core.utils.exceptions.JadxException;
 
-import java.util.List;
-
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-
 @JadxVisitor(
 		name = "ReSugarCode",
 		desc = "Simplify synthetic or verbose code",
@@ -40,6 +40,12 @@ public class ReSugarCode extends AbstractVisitor {
 	private static final Logger LOG = LoggerFactory.getLogger(ReSugarCode.class);
 
 	@Override
+	public boolean visit(ClassNode cls) throws JadxException {
+		initClsEnumMap(cls);
+		return true;
+	}
+
+	@Override
 	public void visit(MethodNode mth) throws JadxException {
 		if (mth.isNoCode()) {
 			return;
@@ -115,7 +121,7 @@ public class ReSugarCode extends AbstractVisitor {
 		if (wrapInsn.getType() != InsnType.AGET) {
 			return;
 		}
-		EnumMapInfo enumMapInfo = checkEnumMapAccess(mth, wrapInsn);
+		EnumMapInfo enumMapInfo = checkEnumMapAccess(mth.dex(), wrapInsn);
 		if (enumMapInfo == null) {
 			return;
 		}
@@ -144,49 +150,40 @@ public class ReSugarCode extends AbstractVisitor {
 		checkAndHideClass(enumMapField.getParentClass());
 	}
 
-	private static EnumMapAttr.KeyValueMap getEnumMap(MethodNode mth, FieldNode field) {
-		ClassNode syntheticClass = field.getParentClass();
-		EnumMapAttr mapAttr = syntheticClass.get(AType.ENUM_MAP);
-		if (mapAttr != null) {
-			return mapAttr.getMap(field);
-		}
-		synchronized (ProcessClass.getSyncObj(syntheticClass)) {
-			mapAttr = new EnumMapAttr();
-			syntheticClass.addAttr(mapAttr);
-
-			MethodNode clsInitMth = syntheticClass.searchMethodByName("<clinit>()V");
+	private static void initClsEnumMap(ClassNode enumCls) {
+		MethodNode clsInitMth = enumCls.getClassInitMth();
 		if (clsInitMth == null || clsInitMth.isNoCode()) {
-				return null;
-			}
-			if (clsInitMth.getBasicBlocks() == null) {
-				try {
-					clsInitMth.load();
-				} catch (DecodeException e) {
-					LOG.error("Load failed", e);
-					return null;
-				}
-				if (clsInitMth.getBasicBlocks() == null) {
-					// TODO:
-					return null;
-				}
+			return;
 		}
+		EnumMapAttr mapAttr = new EnumMapAttr();
 		for (BlockNode block : clsInitMth.getBasicBlocks()) {
 			for (InsnNode insn : block.getInstructions()) {
 				if (insn.getType() == InsnType.APUT) {
-						addToEnumMap(mth, mapAttr, insn);
+					addToEnumMap(enumCls.dex(), mapAttr, insn);
 				}
 			}
 		}
-			return mapAttr.getMap(field);
+		if (!mapAttr.isEmpty()) {
+			enumCls.addAttr(mapAttr);
 		}
 	}
 
-	private static void addToEnumMap(MethodNode mth, EnumMapAttr mapAttr, InsnNode aputInsn) {
+	@Nullable
+	private static EnumMapAttr.KeyValueMap getEnumMap(MethodNode mth, FieldNode field) {
+		ClassNode syntheticClass = field.getParentClass();
+		EnumMapAttr mapAttr = syntheticClass.get(AType.ENUM_MAP);
+		if (mapAttr == null) {
+			return null;
+		}
+		return mapAttr.getMap(field);
+	}
+
+	private static void addToEnumMap(DexNode dex, EnumMapAttr mapAttr, InsnNode aputInsn) {
 		InsnArg litArg = aputInsn.getArg(2);
 		if (!litArg.isLiteral()) {
 			return;
 		}
-		EnumMapInfo mapInfo = checkEnumMapAccess(mth, aputInsn);
+		EnumMapInfo mapInfo = checkEnumMapAccess(dex, aputInsn);
 		if (mapInfo == null) {
 			return;
 		}
@@ -203,7 +200,7 @@ public class ReSugarCode extends AbstractVisitor {
 		if (!(index instanceof FieldInfo)) {
 			return;
 		}
-		FieldNode fieldNode = mth.dex().resolveField((FieldInfo) index);
+		FieldNode fieldNode = dex.resolveField((FieldInfo) index);
 		if (fieldNode == null) {
 			return;
 		}
@@ -211,7 +208,7 @@ public class ReSugarCode extends AbstractVisitor {
 		mapAttr.add(field, literal, fieldNode);
 	}
 
-	public static EnumMapInfo checkEnumMapAccess(MethodNode mth, InsnNode checkInsn) {
+	public static EnumMapInfo checkEnumMapAccess(DexNode dex, InsnNode checkInsn) {
 		InsnArg sgetArg = checkInsn.getArg(0);
 		InsnArg invArg = checkInsn.getArg(1);
 		if (!sgetArg.isInsnWrap() || !invArg.isInsnWrap()) {
@@ -226,7 +223,7 @@ public class ReSugarCode extends AbstractVisitor {
 		if (!inv.getCallMth().getShortId().equals("ordinal()I")) {
 			return null;
 		}
-		ClassNode enumCls = mth.dex().resolveClass(inv.getCallMth().getDeclClass());
+		ClassNode enumCls = dex.resolveClass(inv.getCallMth().getDeclClass());
 		if (enumCls == null || !enumCls.isEnum()) {
 			return null;
 		}
@@ -234,7 +231,7 @@ public class ReSugarCode extends AbstractVisitor {
 		if (!(index instanceof FieldInfo)) {
 			return null;
 		}
-		FieldNode enumMapField = mth.dex().resolveField((FieldInfo) index);
+		FieldNode enumMapField = dex.resolveField((FieldInfo) index);
 		if (enumMapField == null || !enumMapField.getAccessFlags().isSynthetic()) {
 			return null;
 		}