spring-projects/spring-boot · error · ReportableException

Multiple types found with build '{}' and format '{}' use --t

Error message

Multiple types found with build '{}' and format '{}' use --type with a more specific value {}

What it means

Thrown by ProjectGenerationRequest.determineProjectType in detect-type mode when filtering by build and format leaves more than one candidate. The combination is ambiguous and the tool refuses to guess; the message lists the remaining candidate type ids.

Source

Thrown at cli/spring-boot-cli/src/main/java/org/springframework/boot/cli/command/init/ProjectGenerationRequest.java:389

			return result;
		}
		else if (isDetectType()) {
			Map<String, ProjectType> types = new HashMap<>(metadata.getProjectTypes());
			if (this.build != null) {
				filter(types, "build", this.build);
			}
			if (this.format != null) {
				filter(types, "format", this.format);
			}
			if (types.size() == 1) {
				return types.values().iterator().next();
			}
			else if (types.isEmpty()) {
				throw new ReportableException("No type found with build '" + this.build + "' and format '" + this.format
						+ "' check the service capabilities (--list)");
			}
			else {
				throw new ReportableException("Multiple types found with build '" + this.build + "' and format '"
						+ this.format + "' use --type with a more specific value " + types.keySet());
			}
		}
		else {
			ProjectType defaultType = metadata.getDefaultType();
			if (defaultType == null) {
				throw new ReportableException(("No project type is set and no default is defined. "
						+ "Check the service capabilities (--list)"));
			}
			return defaultType;
		}
	}

	/**
	 * Resolve the artifactId to use or {@code null} if it should not be customized.
	 * @return the artifactId
	 */
	protected @Nullable String resolveArtifactId() {

View on GitHub (pinned to 270dfe353f)

Solutions

Pass --type with one of the ids listed in the error message
Run 'spring init --list' to inspect the candidate types
Narrow the selection with additional parameters the server supports

Example fix

// before
$ spring init --build gradle
// after
$ spring init --build gradle --type gradle-project  # chosen from the listed candidates

Defensive patterns

Strategy: validation

Validate before calling

// In detect mode, if filtering leaves >1 candidate, require an explicit type.
InitializrServiceMetadata md = service.loadMetadata(serviceUrl);
java.util.Map<String, ProjectType> candidates = new java.util.HashMap<>(md.getProjectTypes());
if (request.getBuild() != null) filter(candidates, "build", request.getBuild());
if (request.getFormat() != null) filter(candidates, "format", request.getFormat());
if (candidates.size() > 1) {
    throw new IllegalStateException(
        "Ambiguous type; choose one with --type: " + candidates.keySet());
}

Try / catch

try {
    request.determineProjectType(metadata);
} catch (ReportableException ex) {
    if (ex.getMessage().startsWith("Multiple types found")) {
        // the message lists candidate ids; surface them to the user
        Log.error(ex.getMessage());
    }
    throw ex;
}

Prevention

Set --type explicitly whenever more than one type could match
Inspect --list when build/format is ambiguous
Pin --type in automation for reproducible project generation

When it happens

Trigger: Type detection active with a build/format pair that maps to multiple server types, e.g. two gradle types differing by another attribute.

Common situations: Server exposes several types matching the same build+format; user wants determinism but did not pin --type.

Related errors

AI-assisted analysis of spring-projects/spring-boot@270dfe353f (2026-08-11). Data as JSON: /api/errors/224d37fdbf188b8f. Report an issue: GitHub.