feat: generate missing throws declarations, validate exceptions (#2441) (PR #2475)

* fix: generate missing throws declarations, validate exceptions (#2441)

* use ClspGraph.isImplements to check base classes, some code improvements

---------

Co-authored-by: Skylot <[email protected]>

Author: nitram84

jadx-core/src/main/java/jadx/core/Consts.java

@@ -16,7 +16,9 @@ public class Consts {
 	public static final String CLASS_STRING = "java.lang.String";
 	public static final String CLASS_CLASS = "java.lang.Class";
 	public static final String CLASS_THROWABLE = "java.lang.Throwable";
+	public static final String CLASS_ERROR = "java.lang.Error";
 	public static final String CLASS_EXCEPTION = "java.lang.Exception";
+	public static final String CLASS_RUNTIME_EXCEPTION = "java.lang.RuntimeException";
 	public static final String CLASS_ENUM = "java.lang.Enum";
 
 	public static final String CLASS_STRING_BUILDER = "java.lang.StringBuilder";

jadx-core/src/main/java/jadx/core/Jadx.java

@@ -35,6 +35,7 @@
 import jadx.core.dex.visitors.InlineMethods;
 import jadx.core.dex.visitors.MarkMethodsForInline;
 import jadx.core.dex.visitors.MethodInvokeVisitor;
+import jadx.core.dex.visitors.MethodThrowsVisitor;
 import jadx.core.dex.visitors.MethodVisitor;
 import jadx.core.dex.visitors.ModVisitor;
 import jadx.core.dex.visitors.MoveInlineVisitor;
@@ -180,6 +181,8 @@ public static List<IDexTreeVisitor> getRegionsModePasses(JadxArgs args) {
 		passes.add(new ReturnVisitor());
 		passes.add(new CleanRegions());
 
+		passes.add(new MethodThrowsVisitor());
+
 		passes.add(new CodeShrinkVisitor());
 		passes.add(new MethodInvokeVisitor());
 		passes.add(new SimplifyVisitor());

jadx-core/src/main/java/jadx/core/dex/attributes/AType.java

@@ -24,6 +24,7 @@
 import jadx.core.dex.attributes.nodes.MethodInlineAttr;
 import jadx.core.dex.attributes.nodes.MethodOverrideAttr;
 import jadx.core.dex.attributes.nodes.MethodReplaceAttr;
+import jadx.core.dex.attributes.nodes.MethodThrowsAttr;
 import jadx.core.dex.attributes.nodes.MethodTypeVarsAttr;
 import jadx.core.dex.attributes.nodes.PhiListAttr;
 import jadx.core.dex.attributes.nodes.RegDebugInfoAttr;
@@ -76,6 +77,7 @@ public final class AType<T extends IJadxAttribute> implements IJadxAttrType<T> {
 	public static final AType<MethodTypeVarsAttr> METHOD_TYPE_VARS = new AType<>();
 	public static final AType<AttrList<TryCatchBlockAttr>> TRY_BLOCKS_LIST = new AType<>();
 	public static final AType<CodeFeaturesAttr> METHOD_CODE_FEATURES = new AType<>();
+	public static final AType<MethodThrowsAttr> METHOD_THROWS = new AType<>();
 
 	// region
 	public static final AType<DeclareVariablesAttr> DECLARE_VARIABLES = new AType<>();

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

@@ -0,0 +1,40 @@
+package jadx.core.dex.attributes.nodes;
+
+import java.util.Set;
+
+import jadx.api.plugins.input.data.attributes.IJadxAttrType;
+import jadx.api.plugins.input.data.attributes.PinnedAttribute;
+import jadx.core.dex.attributes.AType;
+
+public class MethodThrowsAttr extends PinnedAttribute {
+	private final Set<String> list;
+
+	private boolean visited;
+
+	public MethodThrowsAttr(Set<String> list) {
+		this.list = list;
+	}
+
+	public boolean isVisited() {
+		return visited;
+	}
+
+	public void setVisited(boolean visited) {
+		this.visited = visited;
+	}
+
+	public Set<String> getList() {
+		return list;
+	}
+
+	@Override
+	public IJadxAttrType<MethodThrowsAttr> getAttrType() {
+		return AType.METHOD_THROWS;
+	}
+
+	@Override
+	public String toString() {
+		return "THROWS:" + list;
+	}
+
+}

jadx-core/src/main/java/jadx/core/dex/instructions/args/ArgType.java

@@ -34,7 +34,9 @@ public abstract class ArgType {
 	public static final ArgType STRING = objectNoCache(Consts.CLASS_STRING);
 	public static final ArgType ENUM = objectNoCache(Consts.CLASS_ENUM);
 	public static final ArgType THROWABLE = objectNoCache(Consts.CLASS_THROWABLE);
+	public static final ArgType ERROR = objectNoCache(Consts.CLASS_ERROR);
 	public static final ArgType EXCEPTION = objectNoCache(Consts.CLASS_EXCEPTION);
+	public static final ArgType RUNTIME_EXCEPTION = objectNoCache(Consts.CLASS_RUNTIME_EXCEPTION);
 	public static final ArgType OBJECT_ARRAY = array(OBJECT);
 	public static final ArgType WILDCARD = wildcard();
 

jadx-core/src/main/java/jadx/core/dex/nodes/MethodNode.java

@@ -26,6 +26,7 @@
 import jadx.core.dex.attributes.AType;
 import jadx.core.dex.attributes.nodes.LoopInfo;
 import jadx.core.dex.attributes.nodes.MethodOverrideAttr;
+import jadx.core.dex.attributes.nodes.MethodThrowsAttr;
 import jadx.core.dex.attributes.nodes.NotificationAttrNode;
 import jadx.core.dex.info.AccessInfo;
 import jadx.core.dex.info.AccessInfo.AFType;
@@ -477,11 +478,15 @@ public int getExceptionHandlersCount() {
 
 	@Override
 	public List<ArgType> getThrows() {
+		MethodThrowsAttr throwsAttr = get(AType.METHOD_THROWS);
+		if (throwsAttr != null) {
+			return Utils.collectionMap(throwsAttr.getList(), ArgType::object);
+		}
 		ExceptionsAttr exceptionsAttr = get(JadxAttrType.EXCEPTIONS);
-		if (exceptionsAttr == null) {
-			return Collections.emptyList();
+		if (exceptionsAttr != null) {
+			return Utils.collectionMap(exceptionsAttr.getList(), ArgType::object);
 		}
-		return Utils.collectionMap(exceptionsAttr.getList(), ArgType::object);
+		return Collections.emptyList();
 	}
 
 	/**