fix issues reported by coverity

jadx-core/src/main/java/jadx/core/codegen/InsnGen.java

@@ -535,6 +535,9 @@ public class InsnGen {
 		if (!elType.isTypeKnown()) {
 			LOG.warn("Unknown array element type: {} in mth: {}", elType, mth);
 			elType = insnElementType.isTypeKnown() ? insnElementType : elType.selectFirst();
+			if (elType == null) {
+				throw new JadxRuntimeException("Null array element type");
+			}
 		}
 		insn.mergeElementType(elType);
 

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

@@ -7,6 +7,7 @@ import jadx.core.utils.InsnUtils;
 import java.util.ArrayList;
 import java.util.List;
 
+import org.jetbrains.annotations.Nullable;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -20,6 +21,7 @@ public abstract class InsnArg extends Typed {
 
 	private static final Logger LOG = LoggerFactory.getLogger(InsnArg.class);
 
+	@Nullable("Null for method arguments")
 	protected InsnNode parentInsn;
 
 	public static RegisterArg reg(int regNum, ArgType type) {
@@ -70,6 +72,7 @@ public abstract class InsnArg extends Typed {
 		return false;
 	}
 
+	@Nullable
 	public InsnNode getParentInsn() {
 		return parentInsn;
 	}

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

@@ -52,14 +52,14 @@ public class ConstInlinerVisitor extends AbstractVisitor {
 		long lit = ((LiteralArg) arg).getLiteral();
 
 		SSAVar sVar = insn.getResult().getSVar();
-		if (lit == 0) {
-			if (checkObjectInline(sVar)) {
-				if (sVar.getUseCount() == 1) {
-					insn.getResult().getAssignInsn().add(AFlag.DONT_INLINE);
+		if (lit == 0 && checkObjectInline(sVar)) {
+			if (sVar.getUseCount() == 1) {
+				InsnNode assignInsn = insn.getResult().getAssignInsn();
+				if (assignInsn != null) {
+					assignInsn.add(AFlag.DONT_INLINE);
 				}
-				return false;
 			}
-
+			return false;
 		}
 		ArgType resType = insn.getResult().getType();
 		// make sure arg has correct type

jadx-core/src/main/java/jadx/core/dex/visitors/blocksmaker/BlockFinallyExtract.java

@@ -468,6 +468,10 @@ public class BlockFinallyExtract extends AbstractVisitor {
 		if (pred == null) {
 			return;
 		}
+		IgnoreEdgeAttr edgeAttr = pred.get(AType.IGNORE_EDGE);
+		if (edgeAttr == null) {
+			return;
+		}
 		List<BlockNode> merge = new LinkedList<BlockNode>();
 		for (BlockNode blockNode : pred.getSuccessors()) {
 			if (blockNode.contains(AFlag.RETURN)) {
@@ -488,7 +492,6 @@ public class BlockFinallyExtract extends AbstractVisitor {
 		if (origReturnBlock == null) {
 			return;
 		}
-		IgnoreEdgeAttr edgeAttr = pred.get(AType.IGNORE_EDGE);
 		for (BlockNode mb : merge) {
 			if (mb == origReturnBlock) {
 				continue;

jadx-gui/src/main/java/jadx/gui/update/JadxUpdate.java

@@ -102,7 +102,7 @@ public class JadxUpdate {
 		HttpURLConnection con = (HttpURLConnection) obj.openConnection();
 		con.setRequestMethod("GET");
 		if (con.getResponseCode() == 200) {
-			Reader reader = new InputStreamReader(con.getInputStream());
+			Reader reader = new InputStreamReader(con.getInputStream(), "UTF-8");
 			return GSON.fromJson(reader, type);
 		}
 		return null;