core/src/main/java/io/fabric8/maven/core/util/MavenUtil.java
public static Plugin getPlugin(MavenProject project, String groupId, String artifactId) {
        if (artifactId == null) {
            throw new IllegalArgumentException("artifactId cannot be null");
        }

        List<Plugin> plugins = project.getBuildPlugins();
        if (plugins != null) {
            for (Plugin plugin : plugins) {
                boolean matchesArtifactId = artifactId.equals(plugin.getArtifactId());
                boolean matchesGroupId = groupId == null || groupId.equals(plugin.getGroupId());

                if (matchesGroupId && matchesArtifactId) {
                    return plugin;
                }
            }
        }
        return null;
    }
public static Plugin getPlugin(MavenProject project, String groupId, String artifactId) {
        if (artifactId == null) {
            throw new IllegalArgumentException("artifactId cannot be null");
        }

        List<Plugin> plugins = project.getBuildPlugins();
        if (plugins != null) {
            for (Plugin plugin : plugins) {
                boolean matchesArtifactId = artifactId.equals(plugin.getArtifactId());
                boolean matchesGroupId = groupId == null || groupId.equals(plugin.getGroupId());

                if (matchesGroupId && matchesArtifactId) {
                    return plugin;
                }
            }
        }
        return null;
    }
Returns the plugin with the given groupId (if present) and artifactId.