iBotPeaches/Apktool · error · AndrolibException

Could not smali folder: {smaliDir.getName()}

Error message

Could not smali folder: {smaliDir.getName()}

What it means

SmaliBuilder.build failed while assembling smali sources back into a classes.dex: the smali/dexlib writer threw an IOException, DirectoryException, or RuntimeException (e.g. assembly error from invalid smali). The message names the smali folder being built and keeps the cause.

Source

Thrown at brut.apktool/apktool-lib/src/main/java/brut/androlib/smali/SmaliBuilder.java:96

                    if (cause != null) {
                        ex.initCause(cause);
                    }
                    throw ex;
                }
            }

            if (dexFile.exists()) {
                OS.rmfile(dexFile);
            } else {
                File parentDir = dexFile.getParentFile();
                if (parentDir != null) {
                    OS.mkdir(parentDir);
                }
            }

            dexBuilder.writeTo(new FileDataStore(dexFile));
        } catch (DirectoryException | IOException | RuntimeException ex) {
            throw new AndrolibException("Could not smali folder: " + smaliDir.getName(), ex);
        }
    }

    private boolean buildFile(File smaliFile, DexBuilder dexBuilder) throws IOException, RecognitionException {
        try (InputStreamReader reader = new InputStreamReader(
                Files.newInputStream(smaliFile.toPath()), StandardCharsets.UTF_8)) {
            smaliFlexLexer lexer = new smaliFlexLexer(reader, mApiLevel);
            lexer.setSourceFile(smaliFile);

            CommonTokenStream tokens = new CommonTokenStream(lexer);

            if (PRINT_TOKENS) {
                for (Token token : tokens.getTokens()) {
                    if (token.getChannel() != smaliParser.HIDDEN) {
                        System.out.println(smaliParser.tokenNames[token.getType()] + ": " + token.getText());
                    }
                }
            }

View on GitHub (pinned to 79b63384d7)

Solutions

1. Read the attached cause — for smali syntax errors it pinpoints file and line; fix the reported smali file
2. If you edited smali, validate registers/labels (smali/baksmali tooling or an IDE plugin) before rebuilding
3. Check the output directory is writable and has free space; ensure no stale locked classes.dex blocks the write
4. Retry the decode→build cycle without manual edits to confirm the original smali assembles; if it does not, update apktool (bundled smali version may be too old for the dex)

Example fix

# before
# edited smali_classes2/com/example/MainActivity.smali and broke a register count
apktool b app
# -> Could not smali folder: smali_classes2

# after
# fix the reported line (cause exception names file:line), e.g. restore .registers
apktool b app

// Smoke-assemble smali before a full build is not cheap; instead keep edits minimal and
// verify the decoded project builds BEFORE editing:
//   apktool d app.apk -o orig && apktool b orig   // baseline must pass
// Then diff your edits against orig when a build fails.

try {
    new SmaliBuilder(apkInfo, outDir, apiLevel).build();
} catch (AndrolibException e) {
    if (e.getMessage() != null && e.getMessage().startsWith("Could not smali folder")) {
        Throwable cause = e.getCause();
        // cause is often a smali compile error naming file:line — surface it directly
        log.error("Smali assembly failed in {}: {}", e.getMessage(), cause);
    } else { throw e; }
}

When it happens

Trigger: Calling ApkDecoder.build() / SmaliBuilder on a decoded project where smali files contain syntax or semantic errors, where the output dex path is not writable, or where a parent directory cannot be created. The catch also covers RuntimeExceptions from the dex writer on malformed input.

Common situations: Rebuilding after hand-editing smali and introducing register/label errors; rebuilding on a read-only or full disk; smali edited with an api-level mismatch causing writer failures; leftover classes.dex that cannot be replaced.

Related errors

• Could not open apk file: {apkFile}
• Could not find file: {dexName}
• Cannot disassemble an odex file without deodexing it: {dexNa
• Malicious value for apkFileName: " + mApkFileName
• aapt2 binaries are not available for 32-bit platforms.

AI-assisted analysis of iBotPeaches/Apktool@79b63384d7 (2026-08-14). Data as JSON: /api/errors/64fe4bf4bd63a540. Report an issue: GitHub.