Converting a String to Boolean

[Jamie Wool]

I'm having problems doing the above, have tried numerous things but everything errors, which is frustrating when it's quite a simple thing i want to accomplish(breathe).

  
 
...    }else if (tagName.equals("active")){
       Text textNode = (Text)childElement.getFirstChild();  
       String abdata = textNode.getData();
       //active = Bool.parseBoolean(adata);
       active = Boolean.valueOf((String)abdata);
       //active = Boolean.parse(abdata);
       //boolean actualBool = Boolean.parse(abdata);
 

[Layne Lund]

It would help if you post the exact error message you get.

Layne

[Jamie Wool]

ShrubListParser.java:194: incompatable types
found java.lang.Boolean
required: boolean
active = Boolean.valueOf((String)abdata);

boolean active = false;

[Paul Sturrock]

You are trying to assign a Boolean object to a boolean primative. That won't work. You need to call a method on your Boolean object to get the primative value from it before you can assign it to a primative.

[ramprasad madathil]

>active = Boolean.valueOf((String)abdata);

As Paul said above, this returns a Boolean object. You will have to convert it to primitive boolean

  
   active = Boolean.valueOf((String)abdata).booleanValue();

However this has the effect of first creating a Boolean object from your String object and then converting it inot primitive boolean. Isnt that too many objects for such a task. Always optimize where you can.
Consider using this

  
active = Boolean.getBoolean((String)abdata);

The above directly converts the String object to boolean primitive without the overhead of an intermediate Boolean object.

ram.

[David Harkness]

Originally posted by ramprasad madathil:

active = Boolean.getBoolean((String)abdata);

The above directly converts the String object to boolean primitive without the overhead of an intermediate Boolean object.

The method you want is parseBoolean(String), though getBoolean(String) is related:

public boolean getBoolean(String name)

Returns true if and only if the system property named by the argument exists and is equal to the string "true".

[ramprasad madathil]

Originally posted by David Harkness:
The method you want is parseBoolean(String), though getBoolean(String) is related:

David,
Yes, thanks, teaches me to read the api a bit more carefully here on without taking things for granted, though the method name is a bit misleading, in my humble opinion.
Curiously the method I searched for was parseBoolean() to begin with (I used javap for the search), couldnt find it and that's when I saw this getBoolean() method. Dint bother to check up javadoc to see what it does.
And when I read your post, I was wundering how could I have missed the parseBoolean() method? That's when I went to javadoc and found that
there's indeed no parseBoolean() method either
Am I missing soemthing here? Looks like, unlike other primitives, converting a String to boolean requires converting it to a boolean object first.

ram.

[David Harkness]

Originally posted by ramprasad madathil:
Yes, thanks, teaches me to read the api a bit more carefully here on without taking things for granted, though the method name is a bit misleading, in my humble opinion.

I've started looking up methods when posting answers here, usually to quote something, but also to make sure I'm not thinking of the wrong method. And I agree about the name. I don't see why Boolean.getProperty() wasn't clear enough. Clearly a get method on the Boolean class should need to say it's getting a Boolean!

That's when I went to javadoc and found that
there's indeed no parseBoolean() method either
Am I missing soemthing here?

No, I missed something:

public static boolean parseBoolean(String s)

...

Since:
1.5

Oops!

[ramprasad madathil]

Since:
1.5

oh-oh , ofcourse !! a bit stupid of me, I should have checked that. Anyways, one lives and learns.

Thanks,
ram.