What causes "No BusUtils of ${ext.busUtilsClass} in $mProject." in Blankj/AndroidUtilCode?

Ensure the dependency providing busUtilsClass is on the app classpath, e.g. api 'com.blankj:utilcode:latest.release'.

Blankj/AndroidUtilCode · error · Exception

No BusUtils of ${ext.busUtilsClass} in $mProject.

Error message

No BusUtils of ${ext.busUtilsClass} in $mProject.

What it means

BusPlugin sets busUtilsTransformFile only in scanClassFile(), when it encounters a class whose name equals busUtilsClass. In onScanFinished(), if busUtilsTransformFile is still null (the class was never seen), it throws Exception. There is nothing to inject the event registry into, so the build cannot proceed.

Source

Thrown at plugin/bus-gradle-plugin/src/main/java/com/blankj/bus/BusPlugin.groovy:130

                Map busDetails = [:]
                busDetails.put("BusUtilsClass", ext.busUtilsClass)
                busDetails.put("rightBus", rightBus)
                busDetails.put("wrongBus", wrongBus)
                String busJson = JsonUtils.getFormatJson(busDetails)
                log(jsonFile.toString() + ": " + busJson)
                FileUtils.write(jsonFile, busJson)

                if (wrongBus.size() > 0) {
                    if (ext.abortOnError) {
                        throw new Exception("These buses is not right: " + wrongBus +
                                "\n u can check it in file: " + jsonFile.toString())
                    }
                }

                BusInject.start(busMap, busUtilsTransformFile, ext.busUtilsClass)
            }
        } else {
            throw new Exception("No BusUtils of ${ext.busUtilsClass} in $mProject.")
        }
    }
}

View on GitHub (pinned to 7b4caf9e54)

Solutions

Ensure the dependency providing busUtilsClass is on the app classpath, e.g. api 'com.blankj:utilcode:latest.release'.
Verify busUtilsClass exactly matches the FQN of the BusUtils class present (correct package, no typo).
If using onlyScanLibRegex/jumpScanLibRegex, make sure the jar/module containing BusUtils is not excluded (utilcode is never skipped by isIgnoreScan).

Example fix

// before - busUtilsClass names a class not on the classpath
bus { busUtilsClass "com.example.MyBusUtils" }   // missing -> "No BusUtils of ..."

// after - provide the dependency / correct class
dependencies { api 'com.blankj:utilcode:latest.release' }
bus { busUtilsClass "com.blankj.utilcode.util.BusUtils" }   // or omit the block

Defensive patterns

Strategy: validation

Prevention

Always include the dependency that hosts the configured BusUtils class (utilcode by default).
Double-check the busUtilsClass FQN against the actual class package/name.
Avoid scan-regex rules that would exclude the jar containing BusUtils.

When it happens

Trigger: busUtilsClass names a class not present on the app's compiled classpath; the BusUtils class lives in a jar excluded by onlyScanLibRegex/jumpScanLibRegex; the utilcode dependency is not actually pulled in; the FQN has a typo or wrong package.

Common situations: Configured busUtilsClass "com.xxx.xxx.BusUtils" for a custom copy but the dependency providing it is missing; forgot to add api "com.blankj:utilcode:..."; the BusUtils jar is filtered out by a scan regex.

Related errors

AI-assisted analysis of Blankj/AndroidUtilCode@7b4caf9e54 (2026-08-14). Data as JSON: /api/errors/f2bfcfb104c446c9. Report an issue: GitHub.