core/src/main/java/io/fabric8/maven/core/util/kubernetes/KubernetesResourceUtil.java
private static Map<String, Object> getMetadata(Map<String, Object> fragment) {
        Object mo = fragment.get("metadata");
        Map<String, Object> meta;
        if (mo == null) {
            meta = new HashMap<>();
            fragment.put("metadata", meta);
            return meta;
        } else if (mo instanceof Map) {
            return (Map<String, Object>) mo;
        } else {
            throw new IllegalArgumentException("Metadata is expected to be a Map, not a " + mo.getClass());
        }
    }
private static Map<String, Object> getMetadata(Map<String, Object> fragment) {
        Object mo = fragment.get("metadata");
        Map<String, Object> meta;
        if (mo == null) {
            meta = new HashMap<>();
            fragment.put("metadata", meta);
            return meta;
        } else if (mo instanceof Map) {
            return (Map<String, Object>) mo;
        } else {
            throw new IllegalArgumentException("Metadata is expected to be a Map, not a " + mo.getClass());
        }
    }
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