flowable/flowable-engine · error · FlowableIllegalArgumentException

type is required when deleting a process identity link

Error message

type is required when deleting a process identity link

What it means

FlowableIllegalArgumentException thrown by DeleteIdentityLinkForCaseInstanceCmd.validateParams when the identity-link 'type' argument is null. The CMMN engine requires the link type (e.g. participant, owner) to know which kind of process identity link to remove. It is an argument-validation guard before any persistence work happens.

Source

Thrown at modules/flowable-cmmn-engine/src/main/java/org/flowable/cmmn/engine/impl/cmd/DeleteIdentityLinkForCaseInstanceCmd.java:56

    protected String groupId;
    protected String type;

    public DeleteIdentityLinkForCaseInstanceCmd(String caseInstanceId, String userId, String groupId, String type) {
        
        validateParams(userId, groupId, caseInstanceId, type);
        this.caseInstanceId = caseInstanceId;
        this.userId = userId;
        this.groupId = groupId;
        this.type = type;
    }

    protected void validateParams(String userId, String groupId, String caseInstanceId, String type) {
        if (caseInstanceId == null) {
            throw new FlowableIllegalArgumentException("caseInstanceId is null");
        }

        if (type == null) {
            throw new FlowableIllegalArgumentException("type is required when deleting a process identity link");
        }

        if (userId == null && groupId == null) {
            throw new FlowableIllegalArgumentException("userId and groupId cannot both be null");
        }
    }

    @Override
    public Void execute(CommandContext commandContext) {
        CmmnEngineConfiguration cmmnEngineConfiguration = CommandContextUtil.getCmmnEngineConfiguration(commandContext);
        CaseInstance caseInstance = cmmnEngineConfiguration.getCaseInstanceEntityManager().findById(caseInstanceId);

        if (caseInstance == null) {
            throw new FlowableObjectNotFoundException("Cannot find case instance with id " + caseInstanceId, CaseInstanceEntity.class);
        }

        IdentityLinkUtil.deleteCaseInstanceIdentityLinks(caseInstance, userId, groupId, type, cmmnEngineConfiguration);
        

View on GitHub (pinned to d6d39ce1c6)

Solutions

1. Pass a non-null identity link type (e.g. IdentityLinkType.PARTICIPANT) when calling deleteCaseInstanceIdentityLink
2. Validate the type parameter for null before invoking the service call
3. Check that the enum/form value is converted to a String before passing

Example fix

// before
caseService.deleteCaseInstanceIdentityLink(caseInstanceId, userId, groupId, type);
// after
if (type == null) type = IdentityLinkType.PARTICIPANT;
caseService.deleteCaseInstanceIdentityLink(caseInstanceId, userId, groupId, type);

if (caseInstanceId == null || type == null) throw new IllegalArgumentException("caseInstanceId and type are required");

boolean hasType = (type instanceof String) && !((String) type).isEmpty();

When it happens

Trigger: Calling CaseInstanceService.deleteCaseInstanceIdentityLink(caseInstanceId, userId, groupId, null) or equivalent RuntimeService/TaskService API where the type parameter is passed as null.

Common situations: Developers building custom identity-link management UIs who pass an unset form field for the link type; refactoring code that dropped the type argument; type not mapped from an enum before calling.

Related errors

• userId and groupId cannot both be null
• appDefinitionId is null
• type is required when adding a new task identity link
• identityId is null
• Either set the user id or the group id for an identity link,

AI-assisted analysis of flowable/flowable-engine@d6d39ce1c6 (2026-09-11). Data as JSON: /api/errors/fe150e649382931b. Report an issue: GitHub.