设置org.opensaml.saml2.core.LogoutRequest的ID时出现错误

Question

我正在创建LogoutRequest并使用以下代码设置ID，并收到如下所述的错误。 我还附上了完整的代码片段，以使内容更加清晰。 注意：-如果我未设置ID，则出现异常提示“不存在必需属性：ID”

Error :-
Exception details: 

    System.Xml.XmlException: ID4262: The SAML NameIdentifier 'username' is of format 'urn:oasis:names:tc:SAML:2.0:nameid-format:entity' and its value is not a valid URI.

I have tried with different SAML NameID Format :
 A. urn:oasis:names:tc:SAML:2.0:nameid-format:transient
 B. urn:oasis:names:tc:SAML:2.0:nameid-format:persistent


Complete code
    LogoutRequest logoutReq = new LogoutRequestBuilder().buildObject();
    String randId = UUID.randomUUID().toString();
    logoutReq.setID(randId);
    logoutReq.setDestination("logoutUrl");
        DateTime issueInstant = new DateTime();
        logoutReq.setIssueInstant(issueInstant);
        logoutReq.setNotOnOrAfter(new DateTime(issueInstant.getMillis() + 300000L));

    //Setting issuer
    IssuerBuilder issuerBuilder = new IssuerBuilder();
    Issuer issuer = issuerBuilder.buildObject();
    issuer.setValue("requestEntityID");
        logoutReq.setIssuer(issuer);

        NameID nameId = new NameIDBuilder().buildObject();
        nameId.setFormat("urn:oasis:names:tc:SAML:2.0:nameid-format:entity");
        nameId.setValue("userName");
        logoutReq.setNameID(nameId);

        SessionIndex sessionIndex = new SessionIndexBuilder().buildObject();
        sessionIndex.setSessionIndex("idpSessionIndex");
        logoutReq.getSessionIndexes().add(sessionIndex);
        logoutReq.setReason("Single Logout");