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2nd Annual - SCJP Study Aids Contest !!!

 
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Hey there SCJP candicates !!
It's time again (hence the whole '2nd annual' title), for a study aid contest. (Thanks to Juliane, a recent graduate, who jogged our memories!) Some of you may remember this from last year, here's how it goes:
We want everyone to contribute their favorite, home-made study aid. Maybe it's a short poem about wrappers, maybe it's a limerick about primitives, perhaps it's a mnemonic about the Collection classes.
After a while we'll have a collection of study aids, Kathy and I will retire to our judges chambers, and pick about 4 winners, based on completely arbitrary criteria. The winners will each receive a copy of our SCJP certification book - which will be delivered more slowly than they should, but will eventually get to the winners!
The great thing about this is that these aids is that making them up and reading them really helps in your studies, so really, if you think about it, EVERYBODY'S A WINNER.
Here's a really terrible example:
Since 'unsigned' is a longer word than 'signed', it gets the three >>>, not two >>.
Good luck, and let's see some posts! (You've got at least a week, and we'll give at least a couple of days notice when the end date approaches!)
Bert
 
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Hi Bert:
What is the deadline to submit this?
PI
 
Bert Bates
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Hmmm....


(You've got at least a week, and we'll give at least a couple of days notice when the end date approaches!)



[ February 28, 2004: Message edited by: Bert Bates ]
 
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Hello Bert,
I have some questions regarding this contest.
1>Should the teaching aids be limited to poems, limericks, and mnemonics only, or can they be something else like games, or powerpoint presentations.
2>Where do we post or deliver this study aid.
3>How many such study aids should we prepare.
4>Where should we look out for information like deadlines etc, regarding this contest.
Thank you.
 
Bert Bates
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Hello Bert,
I have some questions regarding this contest.
1>Should the teaching aids be limited to poems, limericks, and mnemonics only, or can they be something else like games, or powerpoint presentations.
2>Where do we post or deliver this study aid.
3>How many such study aids should we prepare.
4>Where should we look out for information like deadlines etc, regarding this contest.
Thank you.


All the information is in this thread! This is a very informal contest
Post all of your study aids right here in this very thread!
I guess the only real limitation is that whatever you post needs to fit into this thread.
Deadlines aren't certain yet, it depends on the turnout, but you have at least one week, and probably more - this is very informal and friendly, we'll post a notice when we think we're close to the end... if someone begs for a little more time, we'll be easy
Post as many as you'd like - you can even post multiples in a single post!
Here's a little flavor of what last year's contest looked like...
https://coderanch.com/t/240390/java-programmer-SCJP/certification/Best-Java-Memory-Aid-Contest
Bert
 
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The letters OS obviously stand for Operating System, however to me they also stand for Object Synchronized. That is, when dealing with threads - the methods in Object (wait, notify, notifyAll) need to be called within a Synchronized block.
OS also came to mean Original Synchronized, that is the difference between Hashtable and HashMap is that one is synchronized the other isn't. The Original (Hashtable) is Synchronized.
ps - Thanks for helping me pass the exam Bert.
 
Bert Bates
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Attn: SCJP candidates!
Ok, at this point Charlie is guaranteed to win! Get those synapses firing! (or neurons )
Bert
ps - Nice idea Charlie, got any more?
 
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Promise not to laugh
I rememeber thread concept like this.
A person can have a key and when he goes to sleep he locks the room and keeps the key with him. (sleep())
A person can have more than one keys (ie) he can have keys of more than one room. (A thread can have more than one locks)
Synchronized is like a private room. When he goes there, he can either lock the private room alone(just the block) or he can choose to lock the entire room(the entire method)
Unsynchronized is like the main room or the room which is not locked. Anybody can access it!!!
so it goes on like this....
I know that you are laughing... STOP IT
Regards,
Raman
 
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This is a short one, but helped me to avoid falling into trick question :
It's MINC not MIC : Map Is Not a Collection.
 
Bert Bates
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Now we're rolling
 
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Here's mine:
ACURA (cars)
Assignment, Conditional and Unary operators have Right Associativity
Rest of them have left associativity.


Cheers,
Sindhur.
[ March 01, 2004: Message edited by: Sindhur Sat ]
 
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How do you like this to remember operator precedence?
U Unary
ARE (a) Arithmetic
LOCAL Logical
COMPUTER Comparison
ASS Assignment
It atleast helped me pass SCJP1.4!
[ March 01, 2004: Message edited by: La Vish ]
 
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Tip 1
Here is my way of remembering which modifiers cannot go along with the modifier "abstract":

Abstract people
1. Do not like SSN numbers.
2. Do not like static (lazy) people
3. Do not like private (secretive) people
4. Do not like finals of any sport.

In technical terms it translates to

The modifier abstract cannot be used along with
1. Strictfp, Synchronized, Native
2. static
3. private
4. final


Tip 2
While preparing for SCJP, I made one simple table to remember the concept of static method overriding.

-----------------------------------------------------------------------
Superclass......Subclass........Compliles?......Polymorphism applies?
-----------------------------------------------------------------------
Non-static......Non-static......Yes.............Yes
Non-static......Static............No................-
Static............Non-static......No................-
Static............Static............Yes..............NO
-----------------------------------------------------------------------

Have a nice day. Bye.
[ March 01, 2004: Message edited by: Sandeep Achar ]
 
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A native Englishman finaly understood the abstract, it was strictly private and handled static electricity.
Abstract can not be used with:
  • native
  • final
  • strictfp
  • private
  • static

  •  
    imre leber
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    Forget about that last one, i forgot synchronized. Still working on it though.
     
    imre leber
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    Here is one:
    01234567 \" BeFoRe TeN '
    All the characters you can use after a \ in a character or string:
    0,1,2,3,4,5,6,7,",',\,b,t,r,n,f
     
    Abdulla Mamuwala
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    This is a poem I have composed on Collections.The important words are highlighted.Here it goes,

    The Collection family is a crazy twist,
    with children Set and List.

    Daughter Set is a freak,
    thats what makes her unique.

    Set has three sons,
    HashSet, LinkedHashSet,TreeSet who like her are fun.
    LinkHashSet is ordered,
    unlike son Hashset,
    who is not bothered and is [/B]unorderd[/B].
    TreeSet follows the natural order,
    for he eats only fodder.
    Thats what makes him sorted
    I hope you have this jotted.

    Lets talk about the family of the next son,
    without any distraction.
    Son List only cares about the index
    for he is male by sex.
    Son List has three sons,
    eldest son Vector is synchronized as,
    Kathy has diagonized.
    Son ArrayList grows fast,
    that too without a cast.
    Son LinkedList is good at fast insertion and deletion,
    that too without excertion.
     
    Abdulla Mamuwala
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    Regarding my poem above, please note that unordered should be bold and extertion in the last line is not bold.
     
    Abdulla Mamuwala
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    Sorry for posting again,
    I wanted to tell, as to what inspired me writing a poem for the Collections class.
    People at SUN, could make a cartoon film or a series of books on Collection or any other topic. Showing Collection as the grand daddy, with sons Set and List and their sons and so on. All these guys having characteristics according to JLS. This would be fun for everyone to learn. This would add a different shade to java, you know cartoon figures and all that stuff, just like the way javaRanch is designed.
    Also studies show that people tend to remeber funny and abstract stuff. Remembering poems and songs is more easy as compared to normal text.
     
    raman padma
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    Hi
    That is too good. The poem about collection will help me in my exam.
    Thanks a lot.
    Raman
     
    raman padma
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    HI
    For Package, Import, Class Order I use "PIC ME PIC ME". The first letters of each word.
    For remembering which length method is for array and String , I remember i can make a ( ) using a string.....so for string, I use length(). For array plain length.

    P.S: As I already have the book, I would prefer something elase as a prize!!!
    Regards,
    Raman
     
    Greenhorn
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    This is how I remember the order of arguments for Thread's constructor. It's silly but it worked for me:
    "good threads negotiate"
    i.e.
    Thread(ThreadGroup group, Runnable target, String name)
    Any combination of arguments in this order is fine, except that Group on its own is invalid, i.e.:
    g t n Constructor
    0 0 0 Thread()
    0 0 1 Thread(name)
    0 1 0 Thread(target)
    0 1 1 Thread(target,name)
    1 0 0 *does not exist*
    1 0 1 Thread(group,name)
    1 1 0 Thread(group,target)
    1 1 1 Thread(group,target,name)
    [ March 03, 2004: Message edited by: Mel Edwards ]
     
    Abdulla Mamuwala
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    Here is how I remember valid modifiers for interface methods and fields
    PAM, Please Sustain Fabulous Figure
    By PAM I mean Pamela Anderson
    Now, lets see what each of the bold letters correspond to,

    Methods
    P public A abstract M method
    Fields
    P public S static Ffinal F field
    That gives us,
    public abstract method, public static final field
    PAM , Please Sustain Fabulous Figure
    I am sure guys will find it hard to forget this one.
     
    Greenhorn
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    Not really mine (I got it from this board a while back) but it makes one of my least favourite questions soooo easy.
    a = x >> y;
    same as:
    a = x/2^y;(2 to the power of y)
    eg.
    a = 99 >> 4;
    same as:
    a = 99/(2*2*2*2);
    result:
    a=6;
    And for left shift
    a = x << y;
    same as:
    a = x * 2^y; (2 to the power of y)
    eg.
    a = 99 << 4;
    same as:
    a = 99 * 2^4; (2*2*2*2)
    result:
    a=1584;
     
    Bert Bates
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    Wow!!!
    We've been offline for a few days - moving across town - just have a few minutes to check in, hoping to be back online in about 24 hours...
    You guys, THESE ARE GREAT!!!
     
    Abdulla Mamuwala
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    To remember how restrictive a particular modifier is, remember the following sentence:
    The public protects by default its private rights.
    public is the most restrictive and private the least thats how they have been ordered in the sentence.
    Note: I have used protects inplace of protected
     
    Sandeep Achar
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    HI Abdullasm,
    I think you got the last one wrong. It should read:
    public is the least restrictive and private the most thats how they have been ordered in the sentence.
     
    Abdulla Mamuwala
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    Firstly, I am extremely sorry for messing it up. I happened to type that in a hurry and a lot of things were going around in my mind too. Again, I am extremely sorry.
    Thanks Sandeep for pointing out my mistake, I will try not to make similar mistake in the future.
    The public protects by default its private rights.
    Correct Explanation:
    public being the least restrictive to private being the most restrictive.
    I hope it helps.
     
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    Here's how I remember bit-count for numeric types:
    I start from the byte, everyone knows it's 8-bit, then just double the bit count for the every other type:
    byte: 8 (we know that from CS101)
    short: 8 * 2 = 16
    int: 16 * 2 = 32
    long: 32 * 2 = 64
    Or is that just too obvious?
     
    Abdulla Mamuwala
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    Although, the trick to remember operator precedence has aldready been posted. I have composed a small poem. The words in bold are the operators. Here it goes,
    Post your creation[\b],
    [b]multiplying, adding, shifting
    ,the relation on every expression,
    equality bitwise is logical and not conditional,
    because this is an assignment which will become tradional.
    Note:
    your-unary
    Also,
    multipying-[b]multiplicative(* / %) so on...
    I hope it helps.
     
    Abdulla Mamuwala
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    I am posting cos, it didnt appear properly the first time.
    Although, the trick to remember operator precedence has aldready been posted. I have composed a small poem. The words in [/b] bold are the operators. Here it goes,
    Post your creation,
    multiplying, adding, shifting,the relation on every expression,
    equality bitwise is logical and not conditional,
    for this is an assignment which will become tradional.
    Note:
    your-unary
    Also,
    multipying-[b]multiplicative(* / %) so on...
     
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    Hi,

    1. Collections end with the letter 's' so does class. So, remember Collections is a class that holds static collection methods.
    - -
    2. parseXxx(), XxxValue(), valueOf()
    If you want to remember which of these methods return Object, just think which has the letter big 'O'? valueOf - O for Object.
    Regards,
    Raman
     
    stable boy
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    Just a little song ...
    Oh, I'm a aspirant and I'm O.K.
    I study all night and I sleep all day
    He's an anspirant and he's O.K.
    He study all night and he sleeps all day
    I type in code, I read my dumps, I take them to the lavatory,
    On Wednesdays I finish debugging and write thirteen lines of Garbage Collection
    He types in code, he prints his dumps, he takes them to the lavatory,
    On Wednesdays he finishes debugging and writes thirteen lines of Garbage Collection
    He's an aspirant and he's O.K.
    He study all night and he sleeps all day
    I type in code, I branch and jump, I bump the switch marked 'power'
    I write modules in C++ that hang the server for hours.
    He types in code, he branches and jumps, he bumps the switch marked 'power'
    He writes modules in C++ that hang the server for hours!?!
    Yeecch!
    He's an anspirant and he's O.K.
    He study all night and he sleeps all day
    I type in code, I spill tape reels, punchcards, and cola
    I wish I'd been an ME, just like my dear mama!
    He types in code, he spills tape reels, punchcards, and... COLA!?!
    [various outraged and incoherent deprecatory mumblings]
    He's a anspirant and he's O.K.
    He study all night and he sleeps all day....
     
    Abdulla Mamuwala
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    This is how I remember some of the Math class fundas.
    1> The Math class is final with static methods,

    Mass Flow Measuring System
    OR
    Multi Functional MachineS
    ____________________________________________________________________
    2>The ceil() and floor() methods accept a double and return a double,
    Have you guys heard of the well known field of,
    Computational Fluid Dynamics------(CFD)
    ___________________________________________________________________
    3>To remember abs() method is overloaded for int, long, float and d[b/]ouble,we use,
    [b]A
    merica Is the Land of the Free and Daring.
    OR
    America is the Land of Freedom and Democracy
    I hope it helps.
     
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    Simple (and stupid), but possibly helpful, when trying to remember override behavior:
    Polly Rides Over Runt Objects meaning, polymorphism uses overriding, and polymorphism is a runtime event that uses the object's type to determine which method to call....
    [ March 10, 2004: Message edited by: Richard Quist ]
     
    Bert Bates
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    Excellent job everyone! We will be going at least through the weekend. We have a good batch of entries here, but for those of you who haven't submitted an entry, I'd say there is still room for a couple of new winners in this batch! So put your thinking caps on, we can't let last year's crowd out do this year's crowd!!!
    Bert
     
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    Hi People,
    A small concept to remember the ststic memebers of java.lang ..
    VIP stands for Very Important Person..ofcourse coz they are static methods in Wrapper Classes
    V - valueOf
    I - isChar,...
    P - parseXXX
    Similarly an easy way to remember about the returns of these methods,
    valueOf returns Object - coz of the O ...
    parseXXX returns primitives coz of the P
    Thanks Guys for your other valuable information.
    RUF
     
    blacksmith
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    Hi there,
    My mnemonic for operator precedence:
    Postfix operators
    Unary operators
    Creation or cast
    Multiplicative
    Additive
    Shift
    Relational
    Equality
    Bitwise AND
    Bitwise exclusive OR
    Bitwise inclusive OR
    Logical AND
    Logical OR
    Conditional
    Assignment
    with the following verses I called 'Cassanova's art'
    or for the ladies in the house 'Cupid's way' between
    brackets:
    Probably
    U
    Can
    Manage
    A
    Single
    Relationship.
    Entertaining
    Babes (Boys)
    Becomes
    Bigamous
    Love:
    Learn (Let)
    Cassanova's (Cupid)
    Art (Arrange)
    Greetings,
    Gian Franco Casula
    [ March 16, 2004: Message edited by: Gian Franco Casula ]
     
    Bert Bates
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    Attention all study aids contestants!!
    If you haven't submitted your entry yet - you've got a few more days...
    If you've already submitted an entry - get another one in here!
    The contest will end at midnight, Colorado time, Friday. Remember, 4 books are up for grabs, and while we've had some great entries there is definitely room for a last minute entry to grab a winning spot.
    Sharpen your pencils!
    Bert
     
    La Vish
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    This stupid "poem" is dedicated to PP Operators.
    Confusion about pre and post fix operators,right?
    follow these simple rules,mate
    Plus plus before the variable?no sweat!
    increment and then assign it
    Plus plus after the variable? Great!
    assign and then increment it
    Minus minus?You work it out!
    [ March 16, 2004: Message edited by: La Vish ]
     
    Don't get me started about those stupid light bulbs.
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