* <pre>
     * message:
     * </pre>
     * @param property The property name for the message. (NotNull)
     * @return this. (NotNull)
     */
    public FessMessages addErrorsFrontHeader(String property) {
        assertPropertyNotNull(property);
        add(property, new UserMessage(ERRORS_front_header));
        return this;
    }

    /**

        when:
        render mutableSetter {
            property('someProperty')
            propertyType('Property<String>')
            includeLink()
        }

        then:
        outputEquals """
Property 'someProperty' of mutable type 'Property<String>' is writable.

Reason: Properties of type 'Property<String>' are already mutable.

Possible solution: Remove the 'setSomeProperty' method.

		<!-- 
		<property name="parameterKey">"fessRoles"</property>
		<property name="encryptedParameterValue">false</property>
		<property name="headerKey">"fessRoles"</property>
		<property name="encryptedHeaderValue">true</property>
		<property name="cookieKey">"fessRoles"</property>
		<property name="encryptedCookieValue">true</property>
		<property name="cipher">

                                     "System.getProperties().get('some.property')",
                                     "getProperties().get('some.property')",
                                     "System.getProperty('some.property')",
                                     "System.getProperty(*['some.property'])",
                                     "getProperty('some.property')",

        val extra = mock<ExtraPropertiesExtension> {
            on { get("property") } doReturn 42
        }

        val property by extra { 42 }

        // property is set eagerly
        verify(extra).set("property", 42)

        // And to prove the type is inferred correctly
        use(property)
    }

    @Test

     * This property will query the entries of the map each time the value of this property is queried.
     *
     * <p>This method can also be used to discard the value of the property, by passing {@code null} as the value.
     * The convention for this property, if any, will be used to provide the value instead.
     *
     * @param entries the entries, can be {@code null}
     */

                property("kind", "SystemProperty")
                comma()
                property("name", trace.name)
            }

            is PropertyTrace.Task -> {
                property("kind", "Task")
                comma()
                property("path", trace.path)
                comma()
                property("type", trace.type.name)
            }

        name = objectFactory.property(String.class);
        url = objectFactory.property(String.class);
        distribution = objectFactory.property(String.class);
        comments = objectFactory.property(String.class);
    }

    @Override
    public Property<String> getName() {
        return name;
    }

    @Override
    public Property<String> getUrl() {
        return url;
    }

        email = objectFactory.property(String.class);
        url = objectFactory.property(String.class);
        organization = objectFactory.property(String.class);
        organizationUrl = objectFactory.property(String.class);
        roles = objectFactory.setProperty(String.class);
        timezone = objectFactory.property(String.class);
        properties = objectFactory.mapProperty(String.class, String.class);
    }

    }

    def "provider modifications should be visible on a view"() {
        given:
        def property = multiValueProperty()
        Collection<String> collection = newCollection(property)

        when:
        property.add("first")
        property.add("second")
        property.add("third")
        property.addAll(["forth", "fifth"])

        then: