Hi
I created three new helper classes with wide usage potential. In specific cases they can significantly simplify the code and make it re-factoring friendly and even faster because there is no need to reference a view object to get an attribute value. I already use them on my daily ADF tasks.
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In short (and exciting)
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(1)
Class DynMap
This is helper class to mimic function call from an EL statement, with one passing parameter.
(2)
Class DynMap2
This is a variant of the upper class allowing you to pass two parameters to a function from an EL statement.
Following the same rules you can create corresponding classes to serve 3 and more parameters, too.
(3)
Class DynMapIn
Cool small class to test if some (binding) value is included in a final set of values.
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In detail (and boring)
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Currently, EL (Expression language) on ADF platform doesn’t support calling functions with parameters. For example you might want to write a (very logical) function call like this:
< af:inputText value="#{mybean.func(bindings.var.inputValue, "V")}" />
...but you can’t do it in ADF. The standard approach is to create a getter on your managed bean, and there to read the attribute from the bindings and do the logic.
public String getFunc(){
DCIteratorBinding iterator = ADFUtils.findIterator("MyIterator");
String myVar1 =iterator.getCurrentRow().getAttribute("MyVar");
String myVar2 =’V’;
//some logic here
return myVar1+”,”+myVar2;
}
And that’s what we usually do, and in most cases it is the only way. A negative consequence of doing it this way is that it that the code cannot be re-factored, because of strings used to reference objects.
I got an idea from how ADF page is using bundles for labels, as it passes a parameter of a key to return associated value. So I used the same idea and constructed a kind of dynamic maps, where the key returned is not a fixed value, but is calculated at the moment of the call. Then I wrapped it all in an easy to use classes.
On the page:
< af:inputText value="#{mybean.func[bindings.var.inputValue]["V"]}" />
In the bean, the getter:
public DynMap getFunc(Object myvar1, Object myvar2){
return new DynMap2() {
@Override
public Object ret(Object var1, Object var2) {
//put some logic here
return var1+","+var2;
}};
}
This is when we have two parameters to pass. And here is a simpler example, when only one parameter has to be passed:
The getter:
public DynMap getFunc(Object myvar) {
return new DynMap() {
@Override
public Object ret(Object var) {
//put some logic here
return var1+"!";
}
};
}
The last example is for testing if a value is included in some set of values:
So instead of:
disabled="#{!(bindings.CriterionTypeId.inputValue=='01'
|| bindings.CriterionTypeId.inputValue=='02'
|| bindings.CriterionTypeId.inputValue=='03'
|| bindings.CriterionTypeId.inputValue=='04'
|| bindings.CriterionTypeId.inputValue=='05'
|| bindings.CriterionTypeId.inputValue=='06'
|| bindings.CriterionTypeId.inputValue=='08'
|| bindings.CriterionTypeId.inputValue=='09'
|| bindings.CriterionTypeId.inputValue=='10'
|| bindings.CriterionTypeId.inputValue=='11'
|| bindings.CriterionTypeId.inputValue=='12'
|| bindings.CriterionTypeId.inputValue=='13'
|| bindings.CriterionTypeId.inputValue=='14'
|| bindings.CriterionTypeId.inputValue=='15'
|| bindings.CriterionTypeId.inputValue=='16'
|| bindings.CriterionTypeId.inputValue=='17'
)}"
...I have to write only:
disabled="#{my_Backing.isDisabled[bindings.ValueTypeId.inputValue]}"
and the getter:
public DynMap getIsDisabled() {
return new DynMapIn("01|02|03|04|05|06|08|09|10|11|12|13|14|15|16|17");
}
Implementations:
public class DynMap extends HashMap {
@Override
public Object get(Object ob) {
return ret(ob);
}
Object ret(Object ob) {
return null;
}
}
public class DynMap2 extends HashMap> {
@Override
public Map get(final Object test1) {
return new HashMap() {
@Override
public Object get(Object test2) {
return ret(test1, test2);
}
};
}
public Object ret(Object test1, Object test2) {
return null;
}
}
public class DynMapIn extends DynMap {
String sInput;
String sDelimiter;
public DynMapIn(String p_sInput) {
super();
sInput = p_sInput;
sDelimiter = ",";
}
@Override
Object ret(Object ob) {
return Arrays.asList(sInput.split(sDelimiter)).contains(ob);
}
}
Regards,
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