class DefaultProjectBuilderConfiguration implements ProjectBuilderConfiguration {

    private ProfileManager globalProfileManager;

    private ArtifactRepository localRepository;

    private Properties userProperties;

    private Properties executionProperties = System.getProperties();

    private Date buildStartTime;

    public DefaultProjectBuilderConfiguration() {}

    public ProjectBuilderConfiguration setGlobalProfileManager(ProfileManager globalProfileManager) {
        this.globalProfileManager = globalProfileManager;
        return this;
    }

    public ProfileManager getGlobalProfileManager() {
        return globalProfileManager;
    }

    public ProjectBuilderConfiguration setLocalRepository(ArtifactRepository localRepository) {
        this.localRepository = localRepository;
        return this;
    }

    public ArtifactRepository getLocalRepository() {
        return localRepository;
    }

    public ProjectBuilderConfiguration setUserProperties(Properties userProperties) {
        this.userProperties = userProperties;
        return this;
    }

    public Properties getUserProperties() {<FILL_FUNCTION_BODY>}

    public Properties getExecutionProperties() {
        return executionProperties;
    }

    public ProjectBuilderConfiguration setExecutionProperties(Properties executionProperties) {
        this.executionProperties = executionProperties;
        return this;
    }

    public Date getBuildStartTime() {
        return buildStartTime;
    }

    public ProjectBuilderConfiguration setBuildStartTime(Date buildStartTime) {
        this.buildStartTime = buildStartTime;
        return this;
    }
}

        if (userProperties == null) {
            userProperties = new Properties();
        }

        return userProperties;
    
<no_super_class>