apache/maven · error · IllegalArgumentException

Cannot inline property {}

Error message

Cannot inline property {}

What it means

PomInlinerTransformer runs when the consumer POM feature is DISABLED: to keep the published POM resolvable, it interpolates the project version and records which properties were inlined. If the version string references a property that is not present in the session's config properties, the callback throws 'Cannot inline property <name>'.

Source

Thrown at impl/maven-core/src/main/java/org/apache/maven/internal/transformation/impl/PomInlinerTransformer.java:130

                .computeIfAbsent(
                        PomInlinerTransformer.class.getName() + ".needsInlining", ConcurrentHashMap::newKeySet);
    }

    @Override
    public void injectTransformedArtifacts(RepositorySystemSession session, MavenProject project) throws IOException {
        if (!Features.consumerPom(session.getConfigProperties())) {
            try {
                Model model = read(project.getFile().toPath());
                String version = model.getVersion();
                if (version == null && model.getParent() != null) {
                    version = model.getParent().getVersion();
                }
                String newVersion;
                if (version != null) {
                    HashSet<String> usedProperties = new HashSet<>();
                    newVersion = interpolator.interpolate(version.trim(), property -> {
                        if (!session.getConfigProperties().containsKey(property)) {
                            throw new IllegalArgumentException("Cannot inline property " + property);
                        }
                        usedProperties.add(property);
                        return (String) session.getConfigProperties().get(property);
                    });
                    if (!Objects.equals(version, newVersion)) {
                        needsInlining(session).addAll(usedProperties);
                    }
                }
            } catch (XMLStreamException e) {
                throw new IOException("Problem during inlining POM", e);
            }
        }
    }
}

View on GitHub (pinned to e4093d4e12)

Solutions

1. Pass the missing property on the command line or CI environment at deploy time: mvn -Drevision=1.2.3 deploy
2. Better: add the flatten-maven-plugin (or enable the consumer POM feature) so the deployed POM has the version inlined for you
3. Define the property in the POM's <properties> with the default expected value
4. Verify with 'mvn help:evaluate -Dexpression=revision' that the property resolves in the exact profile/job that fails

Example fix

# before
mvn deploy   # version is ${revision}, property not set -> Cannot inline property revision

# after
mvn -Drevision=1.2.3 deploy
# or configure flatten-maven-plugin / enable consumer POM in .mvn/maven.config

// before deploy, verify every property referenced by <version> resolves
String v = model.getVersion() != null ? model.getVersion() : model.getParent().getVersion();
for (String p : extractPropertyRefs(v)) { // regex \\$\{([^}]+)\}
    if (!session.getConfigProperties().containsKey(p)) throw new IllegalStateException("Unset property: " + p);
}

catch (IllegalArgumentException e) {
    if (e.getMessage().startsWith("Cannot inline property")) {
        // pass the property with -D, or enable consumer POM/flatten, then retry
    }
}

When it happens

Trigger: A version like <version>${revision}</version> or ${my.version} where the property is not in the effective session configuration — e.g. defined only in a profile that is inactive at install/deploy time, filtered out by CI property injection, or simply missing — combined with consumer POM generation being off.

Common situations: CI pipelines using -Drevision=... where the deploy step runs in a different job without the property; properties defined in a parent that is not resolvable at that point; disabling the consumer POM feature while relying on ${revision}/${sha1}/${changelist} style versions without the flatten-plugin.

Related errors

• Error installing metadata: {}
• Error while deploying metadata: {}
• Unable to read Maven version from maven-core
• The consumer POM for {} cannot be created because the POM co
• Required Maven version {} is not met by current version {}

AI-assisted analysis of apache/maven@e4093d4e12 (2026-08-21). Data as JSON: /api/errors/f41e0c7289f2ddf3. Report an issue: GitHub.