plusConfigurations.addAll(component.getRootConfigurations());
                        plusConfigurations.addAll(component.getLibConfigurations());
                    }
                });

                model.getClasspath().getFile().whenMerged(new Action<Classpath>() {
                    @Override

     */
    public Set<Configuration> getLibConfigurations() {
        return libConfigurations;
    }

    public void setLibConfigurations(Set<Configuration> libConfigurations) {
        this.libConfigurations = libConfigurations;
    }

    /**
     * Synonym for {@link #getLibConfigurations()}.
     */
    public Set<Configuration> getPlusConfigurations() {

        libDirName = wtpComponent.getLibDeployPath();
        Set<Configuration> rootConfigs = wtpComponent.getRootConfigurations();
        Set<Configuration> libConfigs = wtpComponent.getLibConfigurations();
        Set<Configuration> minusConfigs = wtpComponent.getMinusConfigurations();
        rootConfigFiles = collectFilesFromConfigs(model.getClasspath(), rootConfigs, minusConfigs);

        entries.addAll(getEntriesFromConfigurations(project, configOrEmptySet(wtp.getLibConfigurations()), configOrEmptySet(wtp.getMinusConfigurations()), wtp, wtp.getLibDeployPath()));
        component.configure(wtp.getDeployName(), wtp.getContextPath(), entries);
    }

Method <org.gradle.plugins.ide.eclipse.model.EclipseWtpComponent.getLibConfigurations()> does not have raw return type assignable to org.gradle.api.provider.Property in (EclipseWtpComponent.java:0)