JDeveloper 12.2.1.4: responsive af:panelFormLayout

One of the new notable features in JDeveloper 12.2.1.4 is an extension to the af:panelFormLayout component that allows a responsive behavior of the component.

af:panelFormLayout before 12.2.1.4

The image above shows the typical af:panelFormLayout. Actually we see two af:panelFormLayout:

  1. At the top, we see an af:panelFormLayout where we can alter the layout with the af:selectOneChoice. This we use to investigate the new setting
  2. The one at the bottom that just shows the old af:panleFormLayout without any change. This is just there to better see the difference

In the image above both look the same. There is no responsiveness in either panelFormLayout. If the browser window gets smaller than the needed size for the two columns you get

We see that the label now takes two rows, but the inputText components in the second column are clipped.

Changes for 12.2.1.4

JDeveloper 12.2.1.4 added a new property ‘layout’, that changes this behavior to make the component more responsive to changes in the width of the window size.

The new property can have one of three possible values:

  1. Weighted: this is the default. It will size the panelFormLayout to the size to the content and then break the labels if the space gets too small.
  2. Fixed: will size to the width of the screen and truncate the labels and fields
  3. Responsive: will auto arrange the fields in multiple columns and manage labelAlignment based on the space available for the panel

Weighted layout

As this is the default layout (and the only one before 12.2.1.4) we skip this here.

Fixed layout

The image above shows the difference between ‘fixed’ layout (top part) and ‘weighted’ layout (bottom part). Reducing the width of the screen will result in

Still not what we call responsive.

Responsive layout

OK, let’s look at the ‘responsive’ property. If the container width if big enough, it almost looks like the ‘fixed’ layout (see image below).

When the width is reduced the labels are arranged above the input field, which quite an improvement over the weighted layout.

When the width is reduced further, the multi-column layout is reduced to a one-column layout

By default, ADF defined three points or width where the layout changes. These points are defined in the skin and can be changed by altering the skin

af|panelFormLayout {
  -tr-panel-size-sm: 768;
  -tr-panel-size-md: 1024;
  -tr-panel-size-lg: 1281; /* anything greater than this is xl */
}

If you need different points where the layout should change, you can easily change the skin and define different style classes for different scenarios.

The sample was built using JDeveloper 12.2.1.4.0 and can be found at GitHub under BlogResponsivePanelFormLayout.

JDeveloper 12.2.1.4: Exposing Custom Methods from ADFbc ViewObjects to REST API

The new JDeveloper version 12.2.1.4 brought some changes to the ADF business components REST features. One of the features I wondered about is how to expose custom methods built in a view object to the REST API. The release documentation at (https://docs.oracle.com/en/middleware/developer-tools/adf/12.2.1.4/develop/whats-new-this-guide-release-12c-12.2.1.4.0.html#GUID-F0E4CCC6-5419-4FFD-B2F3-E29B40A487DB) says

What does this mean?

The REST part in the documentation still shows some pictures showing the ‘Custom Method’ tab for a REST resource

However. Searching the documentation for ‘custom method’ doesn’t show any result.

Defining a public custom method in the employee’s view and adding it to the client interface (only then methods are visible from the outside)

Looking at the same dialog in JDeveloper 12.2.1.4 does not show the ‘custom method’ tab 😦

So, is the documentation correct?

NO, a hint from @JDeveloper in a tweet gives a hint on this.

Methods are exposed by default!

But how to find them?

Well, let’s try the ‘describe’ operation on the VO using the URL ‘http://127.0.0.1:7101/BlogAdfRestMethod-RESTWebService-context-root/rest/v0/Employees/describe’. This will return plenty of information about the REST API. There we find the information about the Method ‘getVersionInfo’ which I wrote as a custom method in the EmployeesViewObjectImpl class.

To see the method in the REST API, the method must be part of the client interface. This is what the tweet means by ‘updating the metadata’, I guess.

Now, to call the method we use a POST request with the content type set to ‘application/vnd.oracle.adf.action+json’ as noted in the description of the method. The body of the POST request is set to

{
    "name" : "getVersionInfo"
}

Sending the request will give us

I added another method to the EmployeesViewObjImpl method

Named ‘sayHello’. This method I did not expose to the client interface. As we see in the description, this method is not exposed in the REST API. After exposing the method to the client interface too, we get this method in the REST API too.

Now, the description lists

So, the new method can be called via REST too

You can download the sample application from GitHub BlogAdfRestMethod. The sample was built using JDeveloper 12.2.1.4 and uses the HR DB schema.

JDeveloper 12.2.1.4: af:chooseDate

The new JDeveloper 12.2.1.4 has added an enhancement an a new feature to the af:chooseDate component. We are looking at both in this article.

Enhancement

The enhancement is that you can now set a default date which is shown as the selected date when the field you show the af:chooseDate for is empty. In the older JDeveloper versions, the selected date was always the current date. The image below shows the situation of how the af:chooseDate component looks like:

The af:inputText ‘Datum’ is not set and because of this, the af:chooseDate shows the current date (when I took the picture) as the selected date. Problem is, that there are use cases where you don’T want the current date to be the selected date, e.g. your use case might want to show the next Friday after the current date as the selected date. This was not easily possible.

Now, the enhancement to the af:hcooseDate component allows us to set a default date via the property ‘defaultValue’. When set to a literal value, this will be parsed as “yyyy-MM-dd hh:mm:ss” or “yyyy-MM-dd”.

I added an af:inputdate ‘Set DefaultDate’ to allow selection of a date which then will be used as the default date in the af:chooseDate for the ‘Datum’ field. The current date is marked with gray and the date set in the ‘Set Default Date’ is shown as the selected date.

As you see, the ‘Datum’ field is still empty. If you select a date like ‘12/20/2019’ you get

Sample Code

<af:inputDate label="Set Default Date:"
     Nhn ng  value="#{bindings.defaultDate1.inputValue}" id="id2"
     autoSubmit="true"/>
<af:spacer id="s1" height="10px"/>
<af:panelGroupLayout id="pgl2" layout="horizontal">
<af:inputDate label="Datum" id="id1" chooseId="cd1"/>
<af:chooseDate id="cd1"
    defaultValue="#{bindings.defaultDate1.inputValue}"
    partialTriggers="id2"/>

New Feature: “Multiple Date Selection”

The af:chooseDate component has another feature added. Now you can select multiple dates at once. This feature is very handy as you can now use one af:chooseDate to get a start date and an end date or date ranges. The image below shows the component with multiple dates selected.

The interesting thing is, that there is no implementation for this hardcoded in the component. Meaning is that we, the developers, need to implement this feature ourselves. For this ADF provides two new client events ‘load’ and ‘dateSelection’ that are triggered by the af:chooseDate component. We use these client events to implement the multi-select feature. The load event can be used to pass an array of dates to the component which are then shown as selected. This event is triggered when the component loads, as the name implies. The dateSelection event is triggered each time a user selects a date. It passes information about the keyboard state so that we can handle range selection.

To make it easier, the ADF Rich Client Demo has a sample implementation of the needed JavaScript code which I used as the base of my implementation:

/**
 * Shows a popup from an "action" type event.
 * @param {AdfActionEvent} actionEvent the event being handled
 */
var dates = [];
var minDate;
var maxDate;

function dateSelectionEventHandler(event) {
    var eventSource = event.getSource();
    var selectedDate = event.getSelectedDate();
    var modifier = event.getModifiers();

    if (modifier.indexOf(AdfRichChooseDate.MULTI_SELECTION) !=  - 1) {
        dates.push(selectedDate);
    }
    else if (modifier.indexOf(AdfRichChooseDate.RANGE_SELECTION) !=  - 1) {
        if (!minDate || (minDate.getTime() > selectedDate.getTime())) {
            minDate = selectedDate;
        }
        if (!maxDate || (maxDate.getTime() < selectedDate.getTime())) {
            maxDate = selectedDate;
        }
        var timeDiff = Math.abs(maxDate.getTime() - minDate.getTime());
        var diffDays = Math.ceil(timeDiff / (1000 * 3600 * 24)) + 1;
        dates = []
        for (var i = 0;i < diffDays;i++) {
            var selDate = new Date(minDate.getFullYear(), minDate.getMonth(), minDate.getDate() + i, 0, 0, 0, 0);
            if (!eventSource.isDisabled(selDate))
                dates.push(selDate)
        }
    }
    else if (modifier.indexOf(AdfRichChooseDate.SINGLE_SELECTION) !=  - 1) {
        minDate = null;
        maxDate = null;
        dates = []
        dates.push(selectedDate)
    }
    eventSource.setSelectedDates(dates);
}

function chooseDateLoadEventHandler(event) {
    var eventSource = event.getSource();
    eventSource.setSelectedDates(dates);
}

function processSelectedDates(event) {
    component = event.getSource();
    AdfCustomEvent.queue(component, "processSelectedDates", 
    {
        payload : dates
    },
    true);
    event.cancel();
}

There are three JavaScript funtions:

  1. dateSelectionEventHandler(event) handles the selection of one or more dates
  2. chooseDateLoadEventHandler(event) handles the inital load of hte component and allows us to set dates as selected
  3. processSelectedDates(event) is the funtion which passes the selected dates to a server event

The functions are added to the af:chooseDate compponent as client listerner

<af:chooseDate id="cd2" clientComponent="true">
    <af:clientListener type="dateSelection" 
        method="dateSelectionEventHandler"/>
    <af:clientListener type="load" method="chooseDateLoadEventHandler"/>
</af:chooseDate>

To pass the selected dates to a server event a button is used like

<af:button text="Selected Dates" id="b2">
    <af:clientListener method="processSelectedDates" type="action"/>
    <af:serverListener type="processSelectedDates"
        method="#{viewScope.ChooseDateBean.procressSelectedDates}"/>
 </af:button>

The image below shows the selected dates once the button ‘Selected Dates’ is clicked.

This JavaScript function simply passes the array of selected dates as payload from the client to the server. There the dates are just stored in a bean variable. This variable is used to show the dates in an af:outputText.

The same works for a range selection as shown below

And after the button ‘Selected Dates’ is clicked we get

The sample can be downloaded from GitHub BlogChooseDate or directly as a zip. The sample is written using JDeveloper 12.2.1.4 and doesn’t use any DB connection.

JDeveloper 12.2.1.4: af:panelTabbed

The new JDeveloper 12.2.1.4 provides some new features and enhancements. In the next couple of posts we are going to investigate some of them.

We start with the af:panelTabbed component. There is an enhancement fro this component we all waited for a long time. Vertical stacked tabs with icons and text. This sounds like a small thing, but in earlier versions of ADF vertical stacked tabs could only show icons.

We are calling tabs vertical stacked, if the tab is on the left or right side of the panel. Horizontal stacked tabs are the ones at the top or the button of the panel.

Vertical Stacked Tab with Icons and Text

As said before, in earlier versions of ADF you needed to do a workaround to get tabs on the left or right showing an icon, text or both. You needed to create an icon from the icon, Text or icon with text and add it to the af:showDetailItem. The drawback was that you couldn’t just edit the text (e.g. correcting a spelling mistake) or had to generate different such icons for different languages along with some logic to exchange the icon according to the selected language.

The new af:panelTabbed has a new property ‘verticalTabMode‘ with two modes:

  • iconOnly this mode behaves like the old versions and only shows an icon defined for the af:showDetailItem
  • iconAndText this mode shows an icon and the text defined in the text property of the af:showDetailItem
af:panelTabbed with verticalTabMode=”iconOnly’
af:panelTabbed with verticalTabMode=”iconAndText’

The images above show the af:panelTabbed with the new verticalTabMode. The sample application for this can be downloaded from GitHub BlogPanelTabbed. It does not use a DB connection and was built using JDeveloper 12.2.1.4.

JDev 12c: Multi Line Button

An interesting question came up in the JDeveloper & ADF ODC space. A user asked how to display a button which shows a long text in multiple lines.

The image above shows an af:button with a longer text. If you don’t have enough space in your layout to show such a long text in a button, you can shorten the Text. If this is not a acceptable, one solution is to break the long text into multiple lines.

Think about an af:panelSplitter which should show the same button

but the space i for the left pane in the splitter s limited. The result will be that the text of the button can’t be read. In other layouts the button might overflow the given space. his can crumble your whole page layout.

In this blog I’ll show you how to design a button which can handle this situation by showing the text in multiple lines. The green dotted rectangles shows the size of the layout container. This is for information only.

As you see in the image above, the text of the button breaks into multiple lines if the space is not wide enough to show it in one line. If we move the splitter to the right you see the effect

Solution

The solution is to create a style class for the button which we use for button which should be able to show their text in multiple lines. This style class is put into a skin to make it available to the ADF application.

.multiLineButton af|button::text {
    white-space: normal; 
}

The usage of the style class is simple as we see in the sample code for the af:panelSplitter

<af:panelSplitter id="ps1" splitterPosition="100" orientation="horizontal" dimensionsFrom="parent">
	<f:facet name="first">
	        <af:button text="This Button has a very long text to show" id="b3"/>
        </f:facet>
        <f:facet name="second">
                <af:button text="This Button has a very long text to show" id="b4"
                           styleClass="multiLineButton"/>
        </f:facet>
</af:panelSplitter>

You can download the sample BlogMultilineButton (or the zipped workspace) from GihHub. The code was developed using JDeveloper 12.2.1.3 and doesn’t use a DB connection.

Jdev 12c: Implementing SQL IN Clause in an ADF ViewObject Query or ViewCriteria (Part 2)

In part one, showed how to implement a SQL IN clause in ADF. Now I show how to use this technique in a ViewCriteria or directly in a query of a view object.

We have to solve a couple of problems before we can really use the technique from part one in a ViewCriteria. As you know, when using a ViewCriteria, you select an operator which in turn is translated into SQL code. So, we have to find a way to create a new operator which will then be used to create the needed SQL code.

The technique to do this comes from an older post. Please look at Extending ViewCriteria to use SQL CONTAINS where I showed the basics on how to do this. The older post was designed for JDeveloper 11.1.2.1.0. Using the current JDeveloper version 12.2.1.3 give some ways for improvement of the earlier code.

The first improvement is that JDeveloper 12.2.1.3 allows us to introduce custom operators to view criteria. In the older sample, I had to use the description field of the ViewCriteria to pass information which SQL to generate. Now we can define an operator named ‘IN’ and use it in the ViewCriteria like any other default operator.

The next problem is how to generate the SQL shown in part one when the new custom operator ‘IN’ should be used. One of the big advantages of ADF is reusability. We use a base class which extends from ViewObjectImpl and use this new base class in the project.

The base class is named BaseViewObjectForSqlInClause were we implement the needed method

public String getCriteriaItemClause(ViewCriteriaItem aVCI)

which gets called for each part or item of a ViewCriteria. See the code of hte base class below.

Base Class

public class BaseViewObjectForSqlInClause extends ViewObjectImpl {
    private static ADFLogger _logger = ADFLogger.createADFLogger(BaseViewObjectForSqlInClause.class);

    // comma-separated list of custom operators. Each custom operator muast have a ',' at the end as delimeter!
    private static final String CUSTOM_OPERATORS = "IN,";

    public BaseViewObjectForSqlInClause(String string, ViewDefImpl viewDefImpl) {
        super(string, viewDefImpl);
    }

    public BaseViewObjectForSqlInClause() {
        super();
    }

    /**
     * Check if a given criteria item tries to use an 'IN' operator using a bind parameter (comma seperated list of strings).
     * Create special SQL clause for 'IN' operator
     * @param aVCI Criteria item
     * @return where clause part for the criteria item
     */
    @Override
    public String getCriteriaItemClause(ViewCriteriaItem aVCI) {
        // we only handle the SQL 'IN' operator
        String sqloperator = aVCI.getOperator();
        // add comma to operator as delimiter
        boolean customOp = CUSTOM_OPERATORS.indexOf(sqloperator.concat(",")) >= 0;
        customOp |= sqloperator.indexOf("NVL") >= 0;
        if (customOp) {
            ArrayList<ViewCriteriaItemValue> lArrayList = aVCI.getValues();
            if (lArrayList != null && !lArrayList.isEmpty()) {
                // check if the criteria item has bind parameters (only the first if of interest here as the IN clause onlyallows one parameter)
                ViewCriteriaItemValue itemValue = (ViewCriteriaItemValue) lArrayList.get(0);
                if (itemValue.getIsBindVar()) {
                    // get variable and check if null values should be ignored for bind parameters
                    Variable lBindVariable = itemValue.getBindVariable();
                    Object obj = ensureVariableManager().getVariableValue(lBindVariable.getName());
                    boolean b = aVCI.isGenerateIsNullClauseForBindVariables();
                    if (b && obj == null) {
                        // if null values for bind variables should be ignored, use the default getCriteriaItemClause
                        return super.getCriteriaItemClause(aVCI);
                    }

                    try {
                        // we only handle strings data types for bind variables
                        String val = (String) obj;
                    } catch (Exception e) {
                        // the bind variabel has the wrong type! Only Strings are allowed
                        _logger.warning("Bind variabel for SQL " + sqloperator +
                                        " clause is not of type String! -> No custom SQL clause created! (Class: " +
                                        obj.getClass() + ", Content: " + obj + ", Variable: " +
                                        lBindVariable.getName() + ", View: " + this.getName() + ")");
                        String s = ":" + lBindVariable.getName() + " = :" + lBindVariable.getName();
                        return s;
                    }

                    // only handle queries send to the db
                    if (aVCI.getViewCriteria()
                            .getRootViewCriteria()
                            .isCriteriaForQuery()) {
                        String sql_clause = null;
                        switch (sqloperator) {
                        case "IN":
                            sql_clause = createINClause(aVCI, lBindVariable);
                            break;
                        default:
                            _logger.severe("Unknown custom operator '" + sqloperator + "' found! -> do nothing!");
                            break;
                        }

                        return sql_clause;
                    } else {
                        // bind variable not set or
                        // for in memory we don't need to anything so just return '1=1'
                        return "1=1";
                    }
                }
            }
        }

        return super.getCriteriaItemClause(aVCI);
    }

    private String createINClause(ViewCriteriaItem aVCI, Variable lBindVariable) {
        // start build the sql 'IN' where clause (COLUMN is the name of the column, bindParam the name of the bind variable):
        // COLUMN IN (SELECT regexp_substr(:bindParam,'[^,]+',1,level) FROM dual CONNECT BY regexp_substr(:bindParam,'[^,]+',1,level) IS NOT NULL
        // get flagg to create an sql where clause which ignores the case of the bind parameter
        boolean upper = aVCI.isUpperColumns();
        String sql_in_clause = null;
        StringBuilder sql = new StringBuilder();
        if (upper) {
            sql.append("UPPER(");
        }
        sql.append(aVCI.getColumnNameForQuery());
        if (upper) {
            sql.append(")");
        }
        sql.append(" ").append(aVCI.getOperator());
        sql.append(" (select regexp_substr(");
        if (upper) {
            sql.append("UPPER(");
        }
        sql.append(":");
        sql.append(lBindVariable.getName());
        if (upper) {
            sql.append(")");
        }
        sql.append(",'[^,]+', 1, level) from dual connect by regexp_substr(");
        if (upper) {
            sql.append("UPPER(");
        }
        sql.append(":").append(lBindVariable.getName());
        if (upper) {
            sql.append(")");
        }
        sql.append(", '[^,]+', 1, level) is not null)");
        sql_in_clause = sql.toString();

        _logger.finest("generated SQL-IN clause: " + sql_in_clause);

        return sql_in_clause;
    }
}

Using Base Class in Project

To use the base class in all new created ViewObjects of the project, we change the models project properties

Now, whenever you create a new ViewObject, the new base class is used and the SQL IN operator can be used in the VOs view criteria.

You can change any existing ViewObject to use the BaseViewObjectForSqlInClause by changing the extends clause in the class definition by hand.

Creating a ViewCriteria Using the Custom IN Operator

All pieces are in place and using the IN operator is pretty easy. We start by creating a new ViewObject named EmployeesOfDepartmentsViewCriteria

Now we have a ViewObject based on an EntityObject for the Employees. We need to make one change. The DepartmentId is an Integer type attribute, the comma-separated list is of type String (containing numbers). This doesn’t match. We add another attribute to the ViewObject of type String which we calculate from the DepartmentId Integer attribute. We change the SQL query for this by selecting the ‘Query’ node first unselecting the checkbox ‘Calculate Department Query at Runtime (recommended)’, second select the checkbox ‘Write Custom SQL’ and third add the line ‘to_char(Employees.DEPARTMENT_ID) DEPARTMENT_ID_STR,’ to the query.

Once this new ViewObject has been created, we add a ViewCriteria to it

If you like, you can turn off the checkbox ‘Ignore Case’ as it is not needed. The numbers are always lower case.

Running the ApplicationModule in the Tester

At this stage, we can test run the application module in the Application Module Tester (see JDeveloper & ADF: Use the Application Module Tester (BC4J Tester) to Test all your BusinessLogic).

Click the binocular button to select the ViewCriteria we created and click ‘Find’

Which will open a dialog asking for the value of the bind variable

Clicking ‘OK’ will show the result as

Running the ViewCriteria on a Page

Finally, we can add the ViewCriteria to a page as af:query and test it there. I’ll spare the exact howto here and just show hte running application.

Or with different parameters and spaces

You can download the sample application from GitHub BlogSqlInClause.

The Sample was built using JDeveloper 12.2.1.3 (but it should work in all 12c versions) and uses the HR DB schema.

JDev 12c: Implementing SQL IN Clause in an ADF ViewObject Query or ViewCriteria (Part 1)

There have been numerous questions about how to implement a SQL IN clause in ADF using a viewCriteria since the begin of life of ADF. There are a couple of solutions e.g. using an SQL array type or a DB table to store the values of the IN clause.

I came up with another solution which was using Oracle DBs CATSEARCH function or even CONTAINS search index.

All those solutions are more or less complex and need some programming to implement.

The solution I present in this blog is easy and elegant. However, it has its limitations still. Anyway, for about 90% of the use cases, I know where you want to add an SQL IN clause it works perfectly.

Problem

The problem is that you can’t simply define an IN clause in a query or ViewCriteria like

Select * from Employees where employee_id in (:pListOfValues)

Using this select statement as a query for a view object will not throw an error, but it won’t get you the desired result.

If you use a String type parameter for ‘pListOfValues’, e.g. “100, 110, 200” the query in the VO would look like

Select * from Employees where employee_id in (“100,110,200”)

And return nothing as a result. It is easy to see why: the parameter is expanded as a string, not a list of numbers. If you think you could overcome this by converting the employee_id to a string it will still not work as “100” IN “100, 110, 200” still won’t work.

Solution

A very elegant way to solve this problem is to change the query or where clause to

SELECT * FROM TABLE
  WHERE COLUMN IN (
    SELECT regexp_substr(:pListOfValues,'[^,]+',1,level) FROM dual
      CONNECT BY regexp_substr(:pListOfValues,'[^,]+',1,level) 
        IS NOT NULL)

The work is done by the select statement in the IN clause, This statement will split a comma-separated string in a series of values like a sub-select. If you run

SELECT
    regexp_substr(:pListOfvalues, '[^,]+', 1, level)
FROM
    dual
CONNECT BY
    regexp_substr(:pListOfvalues, '[^,]+', 1, level) IS NOT NULL

In a SQL worksheet and pass ‘11,12,15,17’ as ‘pListOfValues’ you get

You can pass any comma-separated string e.g. “1, hello, 444, world” and get

The SQL builds an internal table and add the values delimited by a comma to it. This internal table can then be used in the IN clause of another SQL statement.

Finally, running a complete query we can search e.g. for the employees which have the ID 100 or 110, or 180 or 176

In part 2, I’ll show how to implement this kind of query in a ViewCriteria of a ViewObject by adding a custom operator.

JDev 12.2.1.3: Multi select component table filter

In this blog article, I show how to use a multi-select component as a filter in a table. The sample is based on an older sample from Frank Nimphius (98. How-to use multi select components in table filters). The sample was built for JDev 11g R1 and R2.

It works using 12c too, but you get deprecation warnings after the migration. A user on the JDeveloper & ADF forum asked if I could provide a sample running in 12c without the deprecation warnings.

I will only show how to rewrite the bean method which is called when the user enters one or more values in the filter. The remaining part of the original sample works without a change in 12c.

To better understand what I’m talking about I show some images from the original blog:

The image above shows the sample table. Below we see the multi-select component to filter for multiple departments:

Please read the original blog entry to understand how to build the UI. The remaining part of this blog covers how to build the custom query listener method.

Custom Query Listener

In the original sample the two methods

...
Map _criteriaMap = fqd.getFilterCriteria();
...
fqd.setFilterCriteria(_criteriaMap);

are used which produce deprecation warnings in 12c

Starting from JDev 12.1.3 you can’t use the criteriaMap from the FilterableQueryDescriptor. Instead, you have to first get the ConjunctionCriterion from the FilterableQueryDescriptor and get the map of Criterion from it. The map holds the filter criteria entered by the user.

As you don’t use the criteria directly, you can’t set it back after generating the filter fro the multi-select. You work with the Criterion instead.

The new Method looks like

    /**
     * Custom Query Listener.
     * Applies af:selectMany choice values to the table filter criterion
     * @param queryEvent
     */
    public void onEmployeeTableQuery(QueryEvent queryEvent) {
        //user selected values
        ArrayList<Object> departmentIdArray = null;
        FilterableQueryDescriptor fqd = (FilterableQueryDescriptor) queryEvent.getDescriptor();

        //current criteria
        ConjunctionCriterion conjunctionCriterion = fqd.getFilterConjunctionCriterion();
        Map<String, Criterion> criterionMap = conjunctionCriterion.getCriterionMap();
        Criterion criterion = criterionMap.get("DepartmentId");

        //Translate DepartmentId array list to OR separate list of values
        StringBuffer deptIdFilterString = new StringBuffer();
        AttributeCriterion adfcriterion = null;
        // flag we set only if the DepartmentId filter is set (to reset the selection later)
        boolean flagDepIdFilter = false;
        if (criterion != null) {
            adfcriterion = (AttributeCriterion) criterion;
            Object object = adfcriterion.getValue();
            if (object != null) {
                flagDepIdFilter = true;
                departmentIdArray = (ArrayList<Object>) object;

                for (int argIndex = 0; argIndex < departmentIdArray.size(); argIndex++) {

                    //You need to know what is the underlying data type you are dealing
                    //with for the attribute. If you are on 11gR1 (11.1.1.x) then this
                    //type is jbo.domain.Number for numeric attributes.
                    //
                    //If you are on 11g R2 (11.1.2.x) this could be oracle.jbo.domain.Number,
                    //Integer or BigDecimal. If you use 11g R2, check the View Object for the
                    //attribute data type

                    if (argIndex == 0) {
                        //first argument has no OR

                        //this sample used oracle.jbo.domain.Number for the
                        //DepartmentId attribute
                        Number departmentId = (Number) departmentIdArray.get(argIndex);
                        deptIdFilterString.append(departmentId.toString());
                    } else {
                        //any subsequent argument is OR'ed together
                        deptIdFilterString.append(" OR ");
                        Number departmentId = (Number) departmentIdArray.get(argIndex);
                        deptIdFilterString.append(departmentId.toString());
                    }
                }
                //for some reasons, if in a single value select case, the
                //filter breaks and an error message is printed that the
                //String representation of the single value isn't found in
                //the list. The line below fixes the problem for filter values
                //that are positive numbers
                deptIdFilterString.append(" OR -1");
                String departmentIds = deptIdFilterString.toString();
                adfcriterion.setValue(departmentIds);
                fqd.setCurrentCriterion(adfcriterion);
            }
        }


        // preserve default query listener behavior
        //#{bindings.allEmployeesQuery.processQuery}

        FacesContext fctx = FacesContext.getCurrentInstance();
        Application application = fctx.getApplication();
        ExpressionFactory expressionFactory = application.getExpressionFactory();
        ELContext elctx = fctx.getELContext();

        MethodExpression methodExpression =
            expressionFactory.createMethodExpression(elctx, "#{bindings.allEmployeesQuery.processQuery}", Object.class,
                                                     new Class[] { QueryEvent.class });
        methodExpression.invoke(elctx, new Object[] { queryEvent });

        //restore filter selection done by the user. Note that this
        //needs to be saved as an ArrayList
        if (flagDepIdFilter) {
            adfcriterion.setValue(departmentIdArray);
            fqd.setCurrentCriterion(adfcriterion);
        }
    }

From the FilterableQueryDescriptor we get the ConjunctionCriterion and from this the map of Criterion. This map holds all filter values entered by the user in the filter of the table. We retrieve the one for the ‘DepartmentId’ and check if the value for it is not null. In this case, the criterion holds an array of the selected DepartmentId. From this array, we build a new string where we use the ‘OR’ operator to concatenate the array values.

Once this string is built, we set it back to the Criterion and execute the original query listener

You can download the sample from GtHubBlogMultiSelectComponentFilterTable for inspection and/or testing. The sample was built using JDev 12.2.1.3 and uses the HR DB schema.

JDeveloper: executeWithParams Problem: bind variable setters are not called

In one of my current bigger ADF projects (yes, there are still big ADF projects!) I had a problem with the ‘executeWithParams’ operation binding called from a bean. To understand the problem I first give a brief description.

Problem

We have a special string column in some of our VOs. For this column, there is a bind parameter which is added to the where clause of the VO. Getter and setter for this bind parameters are generated to be able to set this parameter safely. In the setter method, some checks are done and special formatting is applied to the passed value.

Now we used the VOs executeWithParams operation to create a search form. Hitting the button to execute the query gave us a wrong result. As it turned out, that the execWithParams operation passes the parameters to the VO but it doesn’t use the getter/setter methods for the parameter. The parameters are directly set into the slots by the VariableManager.

Solutions

We want to transform or convert the given parameter right in the query. This way the developer doesn’t need to think about or to remember that there should be a transformation of the parameter. A central solution is preferred. Two solutions come to mind.

Expose a method in the VO

One solution would be to create a method in the VO and expose this method in the client interface of the VO. Then this method is visible in the binding layer and you can use call the method instead of using executeWithParams.

This works OK, but if a developer uses the executeWithParams method, you’ll still don’t get the right result.

Change the behavior of the executeWithParams method

I looked for a direct hook into the executeWithParams method but did not find one 😦

However, it turned out that the executeWithParam method calls the executeQuery method of the VO. At this point, the parameters are all set. This is done in the background via the VariableManager used in VOs to keep track of the bind parameters and their different type. There are where clause parameters and parameters used in view criteria. The latter are handled differently but this is not essential for this solution. All we need to know is that the parameters are correctly set when the executeQuery method is called.

The solution is to overwrite the executeQuery method of the view object (or use a base class) and check the parameters before executing the query.

Implementing the solution

In an earlier blog “Dump VO query and it’s parameter with their values” I showed how to get to the parameters defined for a VO and dump their values. Instead of writing the values to the log file, we look for the parameter, change the value, if one is given and then execute the query with the now converted parameter.

I use reflection to check if a setter method for a parameter is defined in the VO. If this is the case, I call the setter with the value set by the user. This way the setter is called when the query is called via the executeWithParams method. The code to change the parameter has only to be written once in the setter.

Below is the code:

    @Override
    public void executeQuery() {
        _logger.info("executeQuery");
        transformHistoryParameter();
        dumpQueryAndParameters();
        super.executeQuery();
    }

    private void transformHistoryParameter() {
        VariableValueManager vm = ensureVariableManager();
        Variable[] variables = vm.getVariables();
        // check each parameter for this query
        for (Variable var : variables) {
            String varName = var.getName();
            try {
                String mName = "set" + varName;
                Class mvarType = var.getJavaType();
                Method m = this.getClass().getMethod(mName, new Class[] { mvarType });
                // check if method is a setter method
                if (isSetter(m)) {
                    Object val = vm.getVariableValue(var);
                    m.invoke(this, val);
                }
            } catch (NoSuchMethodException e) {
                // nothing to do if there is no setter defined
                return;
            } catch (IllegalAccessException | InvocationTargetException e) {
                // nothing to do if there is no setter defined
                return;
            }
        }
    }

    public boolean isGetter(Method method) {
        if (!method.getName().startsWith("get")) {
            return false;
        }
        if (method.getParameterTypes().length != 0) {
            return false;
        }
        if (void.class.equals(method.getReturnType())) {
            return false;
        }
        return true;
    }

    public boolean isSetter(Method method) {
        if (!method.getName().startsWith("set")) {
            return false;
        }
        if (method.getParameterTypes().length != 1) {
            return false;
        }
        return true;
    }

    public void dumpQueryAndParameters() {
        // get the query in it's current state
        String lQuery = getQuery();
        // Dump query
        _logger.info("---query--- " + lQuery);
        //get Valriables
        AttributeList attributeList = getNamedWhereClauseParams();
        String[] attributeNames = attributeList.getAttributeNames();
        if (attributeNames == null || attributeNames.length == 0) {
            _logger.info("--- No variables found");
        } else {
            _logger.info("---Variables:");
            for (int ii = 0; ii < attributeNames.length; ii++) {
                Object lObject = attributeList.getAttribute(ii);
                _logger.info("  --- Name: " + attributeNames[ii] + " Value: " +
                             (lObject != null ? lObject.toString() : "null"));
            }
        }
    }

Sample

The sample to see the code at work can be downloaded from GitHub BlogExecuteWithParamsProblem

It was implemented using JDeveloper 12.2.1.3 and the HR DB schema.

To make it easy, I used the HR DB schema and built a query on the EMPLOYEES table:

A forth bind variable is introduced in a view criteria

The transformation uses the pMail bind parameter and makes it uppercase.

    /**
     * Returns the bind variable value for pMail.
     * @return bind variable value for pMail
     */
    public String getpMail() {
        String val = (String) getNamedWhereClauseParam("pMail");
        _logger.info("value: " + val);
        return val;
    }

    /**
     * Sets <code>value</code> for bind variable pMail.
     * @param value value to bind as pMail
     */
    public void setpMail(String value) {
        _logger.info("value:" + value);
        String newVal = value;
        if (value != null) {
            newVal = value.toUpperCase();
            _logger.info("Value transformed to " + newVal);
        }
        setNamedWhereClauseParam("pMail", newVal);
    }

I know that it would be easy to without this code by just setting the ‘ignore case’ flag when defining the query, but this is just a sample of a change of a parameter.

The data model in the application module looks like

As you see I added a second instance of the EmployeesView and attached the view criteria to this instance. Running the application module in the tester (see JDeveloper & ADF: Use the Application Module Tester (BC4J Tester) to Test all your BusinessLogic)

We get

And the following log

Feb 08, 2019 3:05:38 PM de.hahn.blog.execwithparams.model.EmployeesViewImpl executeQuery
INFO: executeQuery
Feb 08, 2019 3:05:38 PM de.hahn.blog.execwithparams.model.EmployeesViewImpl setpMail
INFO: value:ski
Feb 08, 2019 3:05:38 PM de.hahn.blog.execwithparams.model.EmployeesViewImpl setpMail
INFO: Value transformed to SKI

Feb 08, 2019 3:05:38 PM de.hahn.blog.execwithparams.model.EmployeesViewImpl setpName
INFO: value: null
Feb 08, 2019 3:05:38 PM de.hahn.blog.execwithparams.model.EmployeesViewImpl setpDate
INFO: value: null
Feb 08, 2019 3:05:38 PM de.hahn.blog.execwithparams.model.EmployeesViewImpl dumpQueryAndParameters
INFO: —query— SELECT Employees.EMPLOYEE_ID, Employees.FIRST_NAME, Employees.LAST_NAME, Employees.EMAIL, Employees.PHONE_NUMBER, Employees.HIRE_DATE, Employees.JOB_ID, Employees.SALARY, Employees.COMMISSION_PCT, Employees.MANAGER_ID, Employees.DEPARTMENT_ID FROM EMPLOYEES Employees WHERE ( ( ( ( Employees.LAST_NAME LIKE ( :pName || ‘%’) ) OR ( :pName IS NULL ) ) AND ( ( Employees.EMAIL LIKE ( :pMail || ‘%’) ) OR ( :pMail IS NULL ) ) AND ( ( Employees.HIRE_DATE >= :pDate ) OR ( :pDate IS NULL ) ) ) )
Feb 08, 2019 3:05:38 PM de.hahn.blog.execwithparams.model.EmployeesViewImpl dumpQueryAndParameters
INFO: —Variables:
Feb 08, 2019 3:05:38 PM de.hahn.blog.execwithparams.model.EmployeesViewImpl dumpQueryAndParameters
INFO: — Name: pMail Value: SK
I
Feb 08, 2019 3:05:38 PM de.hahn.blog.execwithparams.model.EmployeesViewImpl dumpQueryAndParameters
INFO: — Name: pName Value: null
Feb 08, 2019 3:05:38 PM de.hahn.blog.execwithparams.model.EmployeesViewImpl dumpQueryAndParameters
INFO: — Name: pDate Value: null
Feb 08, 2019 3:05:38 PM de.hahn.blog.execwithparams.model.EmployeesViewImpl dumpQueryAndParameters
INFO: — Name: pSalary Value: null

We see, that executeQuery() is called, then setpMail is called and the value given in the UI is converted to uppercase. In the dump of the query, we see that the uppercase parameter is used for the query.

The same works with the other view object in the application module. Just try it out yourself. The sample has a small UI project allowing you to test it in the browser too.

JDeveloper 12c: using Expression Language in pageDef to switch ControllerClass

An interesting question came up late 2018 in the JDeveloper & ADF forum. A user asked how to use Expression Language (EL) in a pageDef file to switch the ControllerClass at runtime depending on some condition of a page.

The ControllerClass can be used to add custom code into the lifecycle of a page or fragment (see the full details at 27.4 Customizing the ADF Page Lifecycle). A tip

Tip:
You can specify the value of the page definition’s ControllerClass attribute as a fully qualified class name or you can enter an EL expression that resolves to a class directly in the ControllerClass field.
When using an EL expression for the value of the ControllerClass attribute, the Structure window may show a warning indicating that e “#{YourExpression}” is not a valid class. You can safely ignore this warning.

given in the documentation mentioned that you can use EL to specify the ControllerClass. The missing information is exactly how to do it.

Use Case

For a JSF page, a ControllerClass should be defined at runtime. The selected ControllerClass should depend on a condition.

Solution

There are a couple of blogs available which use a custom ControllerClass in a pageDef, but they use the direct specification of the custom class in the pageDef. Only one sample (https://github.com/oracle/adf-samples/releases/download/v1.0.0/OnPageLoad.zip) from Duncan Mills uses EL to set the ControllerClass. However, this sample was built for JDev 10.3.1! None of the samples I found use EL to switch the ControllerClass at runtime.

In summary, it’s time for a fresh sample using JDev 12.2.1.3

Building the UI

We start by creating a new Fusion Web Application from the gallery. The steps to follow can be looked up at Why and how to write reproducible test cases, so I skip them here.

Once the basic Fusion Web Application is built we open the adfc-config.xml (the unbounded ADF task flow) and add a page onto it.

We name the page index and create it using a Quick Layout. I normally use

but you can use whatever layout like. We add a Text to the header section and an af:inputText and an af:button to the content section. The page markup will look like

<?xml version='1.0' encoding='UTF-8'?>
<!DOCTYPE html>
<f:view xmlns:f="http://java.sun.com/jsf/core" xmlns:af="http://xmlns.oracle.com/adf/faces/rich">
    <af:document title="index.jsf" id="d1">
        <af:form id="f1">
            <af:panelGridLayout id="pgl1">
                <af:gridRow height="50px" id="gr2">
                    <af:gridCell width="100%" halign="stretch" valign="stretch" id="gc1">
                        <!-- Header -->
                        <af:outputText value="Using EL to switch ControllerClass" id="ot1"
                                       inlineStyle="font-size:x-large;"/>
                    </af:gridCell>
                </af:gridRow>
                <af:gridRow height="100%" id="gr1">
                    <af:gridCell width="100%" halign="stretch" valign="stretch" id="gc2">
                        <!-- Content -->
                        <af:panelGroupLayout id="pgl2" layout="horizontal">
                            <af:inputText label="Use Listener" id="it1"/>
                            <af:button text="Update" id="b1"/>
                        </af:panelGroupLayout>
                    </af:gridCell>
                </af:gridRow>
            </af:panelGridLayout>
        </af:form>
    </af:document>
</f:view>

Next, we open the properties of the af:button and edit the actionListener property. Here we create a new bean, name it ‘IndexBean’, create a new method ‘updatePage’. The bean we create in sessionScope. Once the bean has been created, we delete the actionListener from the af:button we just created. The ‘updatePage’ method in the IndexBean we delete too. We don’t need the listener and I only used it to create the bean in the right scope for other things.

I created the bean in session scope as I will use it to store the data from the inputText we added to the page. This is just a convenience, we could have used a pageDef variable for this.

We add a String property ‘usePPListener’ to the IndexBean add the needed getter and setter methods.

public class IndexBean {
    String usePPListener = "1";

    public IndexBean() {
    }

    public void setUsePPListener(String usePPListener) {
        this.usePPListener = usePPListener;
    }

    public String getUsePPListener() {
        return usePPListener;
    }
}

We set the default value of the ‘usePPListener’ to “1”. We set the ‘usePPListener’ to the value property of the af:inputText field of the page. And set the autoSubmit property of the af:inputText to true. The page markup for the content:

<af:gridCell width="100%" halign="stretch" valign="stretch" id="gc2">
    <!-- Content -->
    <af:panelGroupLayout id="pgl2" layout="horizontal">
        <af:inputText label="Use Listener" id="it1" value="#{IndexBean.usePPListener}"
                      autoSubmit="true"/>
        <af:button text="Update" id="b1"/>
    </af:panelGroupLayout>
</af:gridCell>

Running the application at this stage shows

Creating the PagePhaseListener Class

Now we can go on and create the custom PagePhaseListener classes which we then use to switch using an EL. To create such a custom class, the documentation tells us that all we have to do is to create a class which implements the ‘PagePhaseListener’ interface.

This will create the first PagePhaseListener named ‘MyPagePhaseListenerA’. The resulting class looks like

package de.hahn.blog.elpagedef.view.beans;

import oracle.adf.controller.v2.lifecycle.PagePhaseEvent;
import oracle.adf.controller.v2.lifecycle.PagePhaseListener;

public class MyPagePhaseListenerA implements PagePhaseListener {
    public MyPagePhaseListenerA() {
        super();
        System.out.println("MyPagePhaseListenerA created");
    }

    @Override
    public void afterPhase(PagePhaseEvent pagePhaseEvent) {
        // TODO Implement this method
        System.out.println("MyPagePhaseListenerA afterPhase called");
    }

    @Override
    public void beforePhase(PagePhaseEvent pagePhaseEvent) {
        // TODO Implement this method
        System.out.println("MyPagePhaseListenerA beforePhase called");
    }
}

We do it again but name the class ‘MyPagePhaseListenerB’. As you see I added some System.out.println(“…”) statements so that we can see which PagePhaseListener is used later.

Using EL in pageDef.xml

Finally, we start with the interesting part, the EL to use in the pageDef ControllerClass property to switch the listener. The use case demands that we switch the PagePhaseListener depending on a condition. The condition we use is pretty simple:

  • Use MyPagePhaseListenerA if the inputText value stored in usePPListener is equal to “1”
  • Use MyPagePhaseListenerB if the inputText value stored in usePPListener is equal to “2”

We have two options to make the decision,

  1. directly in EL in the pageDef
  2. use a method in a bean where we check the condition

The essential part to know is the type of result both options need to return to work. The ControllerClass expects an object of type PagePhaseListener, or a class which implements this interface.

Solution 1

The classes we created before are implementing this interface, so they should work. To implement option 1 we need to need to instantiate an object of one of the classes and return it on the EL like in the pageDef.xml:

ControllerClass=”#{IndexBean.usePPListener eq ‘1’ ? MyPagePhaseListenerA : MyPagePhaseListenerB}”

And we need to register the bean named ‘MyPagePhaseListenerA’ and ‘MyPagePhaseListenerA’ in the task flow. This will instantiate the object when the task flows starts.

Running this application this way we get

Entering ‘2’ into the af:inputText and clicking ‘Update’ we get

Heureka! The PagePhaseListener have switched as expected.

Solution 2

We implement a method in a bean which returns the right PagePhaseListener class. The EL in the pageDef.xml looks like

ControllerClass="#{IndexBean.pagePhaseListener2Use}"

The method getPagePhaseListener2Use() we implement in the IndexBean as

public PagePhaseListener getPagePhaseListener2Use() {
    if (getUsePPListener() != null && getUsePPListener().equals("2")) {
        return new MyPagePhaseListenerB();
    } else {
        return new MyPagePhaseListenerA();
    }
}

The method returns the PagePhaseListener interface instead of the real class object. This is necessary as a method can only return one object type.

Running the application in this configuration results in exactly the same output we saw before.

Using EL in PageDef for Fragments used in Regions

If you plan to use this technique for fragments which run in regions you would need to return a RegionController instead of a PagePHaseListener. However, as it turned out, you can’t use EL at all in a pageDef of a fragment!

The problem is, that the framework simply doesn’t evaluate the EL you specify for the ControllerClass of a fragment, but uses the EL as the class name. This results in a ‘ClassNotFoundException’ as there is no class named ‘#{your_EL}’.

I’m not sure if this is a bug or a feature. I could not think of a valid use case to use EL for a fragment pageDef.

If you do have one, share it in the comments to this post, please.

If you really think you need to switch the behavior for a RegionController at runtime, you can create one Class which implements the different in the overwritten methods and decide which part to execute inside the method.

Sample

You can download the sample application, which was built using JDev 12.2.1.3 and no DB connection, from GitHub BlogELPageDef