Freemarker布尔属性检索

Question

I have a Customer object which has a boolean attribute letterActivated. The getter method goes as below as per the standard java practices.

public Boolean isLetterActivated() {
    return letterActivated;
}

But seems like Freemaker doesn't pickup customer.letterActivated expression and i guess it might be cause of i don't have getLetterActivated method. (Note that other expressions of customer object works fine which all have get*** methods).

How should i reference this boolean variable from FTL? Note that i'm unable to change the getter method name (isMobileBillingAccount) as it is in existing code and referred in many places. Also it is the correct way for a boolean getter i guess.

Answer 1

Either use public boolean isLetterActivated() or public Boolean getLetterActivated() . The Boolean + is combination doesn't define a JavaBean property according the JavaBeans specification. You don't have to change the name, you can just add the correct getter. Or as a last chance, you can use customer.isLetterActivated() in FTL.

Answer 2

a boolean getter can be name getXXX also.. and as you said there are other references refering with the existing method isLetterActivated . i would suggest doing this since the other references are out of scope to you.

public boolean getLetterActivated() {
    return this.isLetterActivated();
}

This way you dont mess up the existing code and the new code can use the new method... but i think this is a bad design. but given the circumstance i would advice you to go for this.

Answer 3

${customer.letterActivated?c}

Uses isLetterActivated() and
Display "true" if the value is true .

Following code also function without any problem for me ( tested in freemarker 2.3.20 )

<#if (customer.letterActivated)!false>
 Great letter is activated! ${customer.letterActivated?c} man
<#/if>

()!false part is only there to handle null values.

Even more information from freemarker compiler:

Freemarker Compiler output

Can't convert boolean to string automatically, because the "boolean_format" setting was "true,false", which is the legacy default computer-language format, and hence isn't accepted.

Tip: If you just want "true"/"false" result as you are generting computer-language output, use "?c", like ${myBool?c}.

Tip: You can write myBool?string('yes', 'no') and like to specify boolean formatting in place.

Tip: If you need the same two values on most places, the programmers should set the "boolean_format" setting to something like "yes,no".