GoogleContainerTools/jib · error · IllegalArgumentException

manifestTemplateClass + " cannot be instantiated"

Error message

manifestTemplateClass + " cannot be instantiated"

What it means

ImageToJsonTranslator.getManifestTemplate() instantiates the manifest template class via reflection. If the class has no accessible no-arg constructor or cannot be instantiated, the reflective exceptions are wrapped in an IllegalArgumentException naming the class.

Source

Thrown at jib-core/src/main/java/com/google/cloud/tools/jib/image/json/ImageToJsonTranslator.java:214

      // Adds the container configuration reference.
      DescriptorDigest containerConfigurationDigest =
          containerConfigurationBlobDescriptor.getDigest();
      long containerConfigurationSize = containerConfigurationBlobDescriptor.getSize();
      template.setContainerConfiguration(containerConfigurationSize, containerConfigurationDigest);

      // Adds the layers.
      for (Layer layer : image.getLayers()) {
        template.addLayer(
            layer.getBlobDescriptor().getSize(), layer.getBlobDescriptor().getDigest());
      }

      return template;

    } catch (InstantiationException
        | IllegalAccessException
        | NoSuchMethodException
        | InvocationTargetException ex) {
      throw new IllegalArgumentException(manifestTemplateClass + " cannot be instantiated", ex);
    }
  }
}

View on GitHub (pinned to fb949e2676)

Solutions

1. Ensure the manifest template class is public, concrete, and has a public no-arg constructor
2. Use a built-in template such as V22ManifestTemplate or OCIManifestTemplate
3. Check the wrapped cause (ex.getCause()) for the underlying reflection error

Example fix

// before
Image.builder(MyManifestTemplate.class); // abstract / no no-arg ctor
// after
Image.builder(V22ManifestTemplate.class); // public class with implicit no-arg constructor

Class<?> c = manifestTemplateClass;
if (c.isInterface() || Modifier.isAbstract(c.getModifiers()) || c.getConstructors().length == 0)
  throw new IllegalArgumentException(c + " needs a public no-arg constructor");

try { Image.builder(clazz); } catch (IllegalArgumentException e) { inspect e.getCause() (InstantiationException/IllegalAccessException/etc.); }

When it happens

Trigger: Passing a manifestTemplateClass to Image.builder(...) or ImageToJsonTranslator whose class lacks a public no-arg constructor, is abstract, or whose constructor throws; class initialization failure on load.

Common situations: Supplying a custom BuildableManifestTemplate implementation that doesn't follow the no-arg constructor convention; passing an abstract class or interface; classpath/version conflicts where the class's static init fails.

Related errors

• Dependency required by the JAR (as specified in `Class-Path`
• `Main-Class:` attribute for an application main class not de
• `Main-Class:` attribute for an application main class not de
• Invalid container configuration in Docker V2.2/OCI manifest:
• Manifest(s) missing

AI-assisted analysis of GoogleContainerTools/jib@fb949e2676 (2026-09-06). Data as JSON: /api/errors/3ba242287ad07828. Report an issue: GitHub.