Support operation without parameters for JpqlFilter

[GlebDurygin]

Related to #196

Parameterless JpqlFilter can take two values:

1. true - JPQL expression from where and join sections will be added to the data loader query.
2. false- JPQL expression from where and join sections will not be added to the data loader query.

The parameterClass for parameterless JpqlFilter is java.lang.Void and a value class is a java.lang.Boolean.

Parameterless JpqlFilter creation

XML

<filter id="filter"
        dataLoader="customersDl">
    <properties include=".*"/>
    <configurations>
        <configuration id="testConfiguration" name="Test configuration" default="true">
            <jpqlFilter caption="Active == true"
                        parameterClass="java.lang.Void"
                        defaultValue="true">
                <condition>
                    <c:jpql>
                        <c:where>{E}.active = true</c:where>
                    </c:jpql>
                </condition>
            </jpqlFilter>
        </configuration>
    </configurations>
</filter>

Java

    @Subscribe
    protected void onInit(InitEvent event) {
        DesignTimeConfiguration javaConfiguration = filter.addConfiguration("javaConfiguration", "Java configuration");
        DataLoader dataLoader = filter.getDataLoader();

        JpqlFilter<Boolean> jpqlFilter = uiComponents.create(JpqlFilter.NAME);
        jpqlFilter.setFrame(getWindow());
        jpqlFilter.setConditionModificationDelegated(true);
        jpqlFilter.setDataLoader(dataLoader);
        jpqlFilter.setCondition("{E}.active = true", null);
        jpqlFilter.setParameterClass(Void.class);
        jpqlFilter.setCaption("Active == true");
        jpqlFilter.setParameterName(jpqlFilterSupport.generateParameterName(
                jpqlFilter.getId(),
                jpqlFilter.getParameterClass().getSimpleName()));
        jpqlFilter.setValueComponent(singleFilterSupport.generateValueComponent(
                dataLoader.getContainer().getEntityMetaClass(),
                jpqlFilter.hasInExpression(),
                jpqlFilter.getParameterClass()
        ));

        jpqlFilter.setValue(true);
        javaConfiguration.setFilterComponentDefaultValue(jpqlFilter.getParameterName(), jpqlFilter.getValue());

        javaConfiguration.getRootLogicalFilterComponent().add(jpqlFilter);
    }

Run-time

Result

QA

Check the different ways of parameterless JpqlFilter creation.