Win a copy of Java by Comparison (eBook) this week in the Java in General forum!

Danjel Nyberg

Greenhorn
+ Follow
since Sep 12, 2012
Danjel likes ...
Eclipse IDE Java MS IE
Cows and Likes
Cows
Total received
0
In last 30 days
0
Total given
0
Likes
Total received
0
Received in last 30 days
0
Total given
1
Given in last 30 days
0
Forums and Threads
Scavenger Hunt
expand Ranch Hand Scavenger Hunt
expand Greenhorn Scavenger Hunt

Recent posts by Danjel Nyberg

How to add your name to the wall of fame?

/Danjel
Hi

I passed the OCAJP7 1Z0-803 exam today with 90%
I have used the enthuware mock exams to study.

Thank you all for support and sharing of knowledge

Kind Regards
/Danjel
5 years ago
I would say that this line of code would not compile



however if you put it like this, then it would work



Regards
/Danjel
I was just tweaking a bit and stumbled across something strange, which i can't explain

given this simple class:


this gives different output every time i run it...

expected output is:

0
1
2
3
4
Exception in thread "main" java.lang.Exception
at SCJP.Test18.main(Test18.java:9)

but if I run it several times it could give me this output:

0
1Exception in thread "main" java.lang.Exception
at SCJP.Test18.main(Test18.java:9)

2
3
4

My only explenation to this is that the update of output to the Eclipse console is not keeping up.

Any ideas or input?


/Danjel
Returns a fixed-size list backed by the specified array. (Changes to the returned list "write through" to the array.) This method acts as bridge between array-based and collection-based APIs, in combination with Collection.toArray(). The returned list is serializable and implements RandomAccess.

/Danjel
Sorry for this, was just spinning off of the recent chars not compiling threads, plus i though i'd give you some fun for the weekend. perhaps the wrong forum.

Kind Regards
/Danjel
What is the output of this?



Have a nice weekend everyone!
/Danjel

[John] Split long lines in post
One point... The default constructor of a singleton instance should be private. You can also use Enums for singleton




/Danjel

Same goes for strings...

String a = "Test";
String b = "Test";
System.out.println(a==b); //prints true
String c = new String("Test");
System.out.println(a==c); //prints false

In this case since a and b are created via string litherals they point to the same object, but since c is created with new keyword this will be another object and therefore a is not the same as c

This is wierd in so many ways. In all normal cases you allways compare objects with equals method only...

/Danjel
Of course... absolutely correct, and so are protected (in the same package)

/Danjel
Hi

Not quite sure how that differs from what i stated above. A Default accessed attribute in a superclasss is accessible in a subclass of superclass as long as they are in the same package.

In difference here from protected:

The above method would work if i change: Account acc = new Account(); to GoldAccount acc = new GoldAccount();
as they are in different packages, but if accountNo would have been declared with default access, this should not work. (if they are in different packages)

/Danjel
Realized that only minutes after posting.. sometimes it is good to just write it down... got it now.

Thanks
/Danjel
I state the following...

public - everyone can access methods and attributes of the class
protected - class, and every subclass of class no matter of the package can access
private - only class can access
default - class, and every subclass can access if they are in the same package

accesscontrol

Question im having trouble with:


another package... another class...
[Added code tags - see UseCodeTags]

This gives a compilation error, any suggestions as to what mistake i might have made?

/Danjel
Hi

You can also convert decimals to binary with:
Integer.toBinaryString(a);

Where a is of type int

and convert binary string to decimals with:
int a = Integer.parseInt(s1, 2);
where s1 is of type string

also adding and removing specific bits from a binary is possible with follwing code:



Kind Regards
/Danjel
Can not find this book, can anyone point out a store who sells this book?

Right now im training with the EPractize labs. Is this a good way to train for the OCA 7?

/Danjel