bumptech/glide · error · RuntimeException

Unable to instantiate GlideModule implementation for {clazz}

Error message

Unable to instantiate GlideModule implementation for {clazz}

What it means

Thrown by ManifestParser.throwInstantiateGlideModuleException when reflective instantiation of a registered GlideModule class fails. Wraps one of InstantiationException, IllegalAccessException, NoSuchMethodException, or InvocationTargetException, indicating the class itself was found (Class.forName succeeded) but a new instance could not be created.

Source

Thrown at library/src/main/java/com/bumptech/glide/module/ManifestParser.java:105

      // These can't be combined until API minimum is 19.
    } catch (InstantiationException e) {
      throwInstantiateGlideModuleException(clazz, e);
    } catch (IllegalAccessException e) {
      throwInstantiateGlideModuleException(clazz, e);
    } catch (NoSuchMethodException e) {
      throwInstantiateGlideModuleException(clazz, e);
    } catch (InvocationTargetException e) {
      throwInstantiateGlideModuleException(clazz, e);
    }

    if (!(module instanceof GlideModule)) {
      throw new RuntimeException("Expected instanceof GlideModule, but found: " + module);
    }
    return (GlideModule) module;
  }

  private static void throwInstantiateGlideModuleException(Class<?> clazz, Exception e) {
    throw new RuntimeException("Unable to instantiate GlideModule implementation for " + clazz, e);
  }
}

View on GitHub (pinned to eb14a895d8)

Solutions

1. Ensure the GlideModule class has a public no-arg constructor and make no-arg construction safe (no I/O, no required args)
2. If the module needs config, read it lazily in registerComponents/applyOptions instead of in the constructor
3. Add ProGuard keep rules for the constructor: -keepclassmembers class * { public <init>(); }
4. Inspect the wrapped cause exception (InvocationTargetException.getCause) to find the real failure inside the constructor

Example fix

// before
class MyGlideModule(private val cacheDir: File) : GlideModule { /* ... */ }

// after
class MyGlideModule : GlideModule {
  override fun registerComponents(context: Context, glide: Glide, registry: Registry) {
    val cacheDir = context.cacheDir // obtain lazily, not in constructor
  }
}

val ctor = clazz.getDeclaredConstructor()
require(Modifier.isPublic(ctor.modifiers)) { "GlideModule needs public no-arg ctor" }
require(!Modifier.isAbstract(clazz.modifiers)) { "GlideModule must be concrete" }
ctor.newInstance() // validate it constructs without throwing

try {
  ManifestParser(ctx).parse()
} catch (e: RuntimeException) {
  // e.cause reveals Instantiation/IllegalAccess/NoSuchMethod/InvocationTarget
  logAndFallback(e)
}

When it happens

Trigger: The registered module class has no public no-arg constructor (NoSuchMethodException); the constructor is private or protected (IllegalAccessException); the class is abstract or an interface or an array (InstantiationException); or the no-arg constructor throws an exception at runtime (InvocationTargetException).

Common situations: A GlideModule whose constructor requires arguments (DI-injected config); a module class made abstract by mistake; a constructor that performs work that fails on certain devices/OS versions (e.g. reading a file or initializing a native lib); constructor visibility changed by ProGuard obfuscation.

Related errors

• Unable to find GlideModule implementation
• Expected instanceof GlideModule, but found: {module}
• Constructor for {} accepts too many parameters, it should ac
• Unrecognized type: {}
• RequestOptionsExtensions must be public, with private constr

AI-assisted analysis of bumptech/glide@eb14a895d8 (2026-08-14). Data as JSON: /api/errors/aef7d98a4f76e2a6. Report an issue: GitHub.