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\usepackage{seqsplit}           % Splits long words.
%\usepackage{opensans}          % Can't make this work so far. Shame. Would be lovely.
\usepackage[normalem]{ulem}     % For underlining links
% Most of the following are not required for the majority
% of cheat sheets but are needed for some symbol support.
\usepackage{amsmath}            % Symbols
\usepackage{MnSymbol}           % Symbols
\usepackage{wasysym}            % Symbols
%\usepackage[english,german,french,spanish,italian]{babel}              % Languages

% Document Info
\author{Edgar (edgarjoel21)}
\pdfinfo{
  /Title (ood.pdf)
  /Creator (Cheatography)
  /Author (Edgar (edgarjoel21))
  /Subject (OOD Cheat Sheet)
}

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% Header and Footer
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\fancyhead[L]{
\noindent
\begin{multicols}{3}
\begin{tabulary}{5.8cm}{C}
    \SetRowColor{DarkBackground}
    \vspace{-7pt}
    {\parbox{\dimexpr\textwidth-2\fboxsep\relax}{\noindent
        \hspace*{-6pt}\includegraphics[width=5.8cm]{/web/www.cheatography.com/public/images/cheatography_logo.pdf}}
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\columnbreak
\begin{tabulary}{11cm}{L}
    \vspace{-2pt}\large{\bf{\textcolor{DarkBackground}{\textrm{OOD Cheat Sheet}}}} \\
    \normalsize{by \textcolor{DarkBackground}{Edgar (edgarjoel21)} via \textcolor{DarkBackground}{\uline{cheatography.com/44289/cs/14900/}}}
\end{tabulary}
\end{multicols}}

\fancyfoot[L]{ \footnotesize
\noindent
\begin{multicols}{3}
\begin{tabulary}{5.8cm}{LL}
  \SetRowColor{FootBackground}
  \mymulticolumn{2}{p{5.377cm}}{\bf\textcolor{white}{Cheatographer}}  \\
  \vspace{-2pt}Edgar (edgarjoel21) \\
  \uline{cheatography.com/edgarjoel21} \\
  \end{tabulary}
\vfill
\columnbreak
\begin{tabulary}{5.8cm}{L}
  \SetRowColor{FootBackground}
  \mymulticolumn{1}{p{5.377cm}}{\bf\textcolor{white}{Cheat Sheet}}  \\
   \vspace{-2pt}Not Yet Published.\\
   Updated 27th February, 2018.\\
   Page {\thepage} of \pageref{LastPage}.
\end{tabulary}
\vfill
\columnbreak
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  \mymulticolumn{1}{p{5.377cm}}{\bf\textcolor{white}{Sponsor}}  \\
  \SetRowColor{white}
  \vspace{-5pt}
  %\includegraphics[width=48px,height=48px]{dave.jpeg}
  Measure your website readability!\\
  www.readability-score.com
\end{tabulary}
\end{multicols}}




\begin{document}
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% www.emerson.emory.edu/services/latex/latex_169.html
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\begin{multicols*}{4}

\begin{tabularx}{3.833cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{3.833cm}}{\bf\textcolor{white}{Design Principles}}  \tn
\SetRowColor{white}
\mymulticolumn{1}{x{3.833cm}}{1. Javadoc all public classes and methods. Class comment should be at least two sentences, and provide information not already clear from its definition. \newline % Row Count 4 (+ 4)
2. Use interface types over concrete classes wherever possible. Exception: immutable "value" objects. Classes with no interface. \newline % Row Count 7 (+ 3)
3. Fields must always be private. Exception: constants. Methods, classes should be as private as possible. \newline % Row Count 10 (+ 3)
4. Class should never have public methods not in the interface (aside from constructor). \newline % Row Count 12 (+ 2)
5. Composition over inheritance. \newline % Row Count 13 (+ 1)
6. Catch and handle/report errors as early as possible. Use Java compiler checks, enums, final first, runtime checks second. \newline % Row Count 16 (+ 3)
7. Use class types over strings. \newline % Row Count 17 (+ 1)
8. Check inputs. \newline % Row Count 18 (+ 1)
9. Use exceptions only for exceptional situations -{}- not for flow control. \newline % Row Count 20 (+ 2)
10. Checked vs unchecked: checked: reasonable expectation that the program can recover. Unchecked: programmer error (may still be recoverable). \newline % Row Count 23 (+ 3)
11. Don't leave things in an inconsistent state for any substantive length of time. \newline % Row Count 25 (+ 2)
12. Beware of references, copies, and mutation. Make defensive copies. \newline % Row Count 27 (+ 2)
13. Separate responsibilities: one class, one responsibility. \newline % Row Count 29 (+ 2)
14. Use class hierarchies and dynamic dispatch over tagged classes, complex if/switch statements. \newline % Row Count 31 (+ 2)
} \tn 
\end{tabularx}
\par\addvspace{1.3em}

\vfill
\columnbreak
\begin{tabularx}{3.833cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{3.833cm}}{\bf\textcolor{white}{Design Principles (cont)}}  \tn
\SetRowColor{white}
\mymulticolumn{1}{x{3.833cm}}{15. Don't duplicate code. \newline % Row Count 1 (+ 1)
16. Open for extension, closed for modification: make changes without modifying existing code; write code to support later changes without modification. \newline % Row Count 5 (+ 4)
17. Extensibility: design to make likely later changes easier. \newline % Row Count 7 (+ 2)
18. Write tests first, cover the range of situations, edge cases. Write code to be testable (avoid System.out); do not expose fields or add public methods just to allow for testing. \newline % Row Count 11 (+ 4)
19. Loose coupling over tight coupling (avoid System.out). Write reusable components when possible. \newline % Row Count 13 (+ 2)
20. You can't change an interface once it's published. \newline % Row Count 15 (+ 2)
21. If you override equals(), override hashCode(), and vice-versa. \newline % Row Count 17 (+ 2)
22. Reuse existing exceptions, classes, libraries, and designs.% Row Count 19 (+ 2)
} \tn 
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\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{3.833cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{3.833cm}}{\bf\textcolor{white}{Scanner Methods}}  \tn
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{3.833cm}}{`public boolean hasNext() Returns true if the scanner has another token in its input` \newline `public String next() Finds and returns the next complete token from the sc (throws NoSuchElement if no tokens and IllegalState if scanner is closed` \newline `Scanner(Readable source) Constructs a new Scanner that produces values scanned from the specified source.` \newline `Readable r = new StringReader(String);` \newline `Appendable a = new StringBuilder(); THROWS EXCEPTION`} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{3.833cm}{x{1.16722 cm} x{2.26578 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{3.833cm}}{\bf\textcolor{white}{CLASS INVARIANTS}}  \tn
% Row 0
\SetRowColor{LightBackground}
NOT INVARIANTS & INVARIANT \tn 
% Row Count 2 (+ 2)
% Row 1
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value is small & A logical statement is a claim that is true or false \tn 
% Row Count 4 (+ 2)
% Row 2
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value never decreases & The instantanous state of an object is the combination of values of all its fields at some point in time \tn 
% Row Count 8 (+ 4)
% Row 3
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value is an int & The invariant is ensured by constructors in the sense that whenever a public constructor returns, the logical statement holds \tn 
% Row Count 13 (+ 5)
% Row 4
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 & Preserving the logical statement means that the method doesn't introduce nonsense - instead, we know that if given a object in a good state then it will leave the object in a good state as well \tn 
% Row Count 21 (+ 8)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\SetRowColor{LightBackground}
\mymulticolumn{2}{x{3.833cm}}{Enables a form of reasoning called rely-guarantee.  \newline - If the constructor ensures some property \newline - and every method preserves the property \newline - then every public method, on entry, can rely on the property}  \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{3.833cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{3.833cm}}{\bf\textcolor{white}{Composition over inheritance}}  \tn
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{3.833cm}}{- Composition over inheritance \newline - delegate design pattern: take the previous code we want to use and make it a field instead of extending it  \newline - has-a instead of is-a  \newline - always get copies of every private field instead of passing in the real thing \newline  \newline public boolean remove(int i) \{ \newline     return deletgate.remove(i); \newline \} \newline  \newline public boolean contains(int i) \{ \newline    return delegate.contains(i); \newline \}} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{3.833cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{3.833cm}}{\bf\textcolor{white}{Map methods}}  \tn
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{3.833cm}}{clear() \newline containsKey(Object key) \newline containsValue(Object value) \newline entrySet() returns a set view of the mappings (Set\textless{}Map.Entry\textless{}K, V\textgreater{}\textgreater{}) \newline equals(Object o) \newline get(Object key) \newline hashCode() \newline isEmpty() \newline keySet() returns a set of the keys Set\textless{}K\textgreater{} \newline put(k key, V value) Associates the value with the key \newline putAll(Map\textless{}? extends K, ? extends V\textgreater{} m) Copies into new map  \newline remove(Object key) \newline size() \newline values() Returns a Collection view of the values (Collection\textless{}V\textgreater{})} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{3.833cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{3.833cm}}{\bf\textcolor{white}{Equals}}  \tn
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{3.833cm}}{@Override \newline public boolean equals(Object that) \{ \newline    if (this == that) \{ \newline       return true; \newline    \} \newline    if (!(that instanceof Duration)) \{ \newline       return false; \newline    \{ \newline    return ((Duration) that).inSeconds() == this.inSeconds(); \newline   \}} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{3.833cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{3.833cm}}{\bf\textcolor{white}{Stack Methods}}  \tn
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{3.833cm}}{`empty()`  Tests if this stack is empty (boolean)| \newline `peek()` Looks at top object of stack without removing it (E) | \newline `pop()` Removes the object at the top of this stack and returns that object (E)|  \newline `push(E item)` Pushes an item onto the top of this stack (E) | \newline `search(Object o)` Returns the 1-based position where an object is on this stack (int)  | \newline `add, add, addAll, addAll, addElement, capacity, clear, clone, contains, containsAll, copyInto, elementAt, elements, ensureCapacity, equals, firstElement, get, hashCode, indexOf, indexOf, insertElementAt, isEmpty, iterator, lastElement, lastIndexOf, lastIndexOf, listIterator, listIterator, remove, remove, removeAll, removeAllElements, removeElement, removeElementAt, removeRange, retainAll, set, setElementAt, setSize, size, subList, toArray, toArray, toString, trimToSize`} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{3.833cm}}{`Deque\textless{}E\textgreater{} is an interface (double ended queue)` \newline `Deque\textless{}Integer\textgreater{} stack = new ArrayDeque\textless{}Integer\textgreater{}();`}  \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{3.833cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{3.833cm}}{\bf\textcolor{white}{TIps}}  \tn
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{3.833cm}}{- check for overflow  \newline - canonicalize means converting data with multiple representations into a standard or normal form \newline - bug may be that a method used a non-copy of something \newline - interfaces can be extended to add methods to something} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{3.833cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{3.833cm}}{\bf\textcolor{white}{Static}}  \tn
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{3.833cm}}{Static: Java's version of global variables \newline Static Methods: Called on the class rather than an instance and thus dont have a this to work on. Ex: Long.hashCode() \newline Static classes: behave like normal classes just nested in its enclosing classes namespace. Outer.nested is how you refer to it. Outer.nested can see outers private members and vise versa \newline - constants should be public static final and in all caps} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{3.833cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{3.833cm}}{\bf\textcolor{white}{Hashcode}}  \tn
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{3.833cm}}{@Override \newline public int hashCode() \{ \newline    return Object.hash(field, field, field); \newline    \}} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{3.833cm}}{Must use fields that equals uses}  \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{3.833cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{3.833cm}}{\bf\textcolor{white}{ABSTRACT TEST}}  \tn
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{3.833cm}}{protected abstract FreecellOperations\textless{}Card\textgreater{} freecellModel(); \newline  \newline   public static class SingleMove extends \seqsplit{AbstractFreecellModelTests2} \{ \newline  \newline  \newline     @Override \newline     protected FreecellOperations\textless{}Card\textgreater{} freecellModel() \{ \newline       return \seqsplit{FreecellModelCreator.create(GameType.SINGLEMOVE);} \newline     \} \newline   \} \newline  \newline   public static class MultiMove extends \seqsplit{AbstractFreecellModelTests2} \{ \newline     @Override \newline     protected FreecellOperations\textless{}Card\textgreater{} freecellModel() \{ \newline       return \seqsplit{FreecellModelCreator.create(GameType.MULTIMOVE);} \newline     \}} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{3.833cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{3.833cm}}{\bf\textcolor{white}{Array}}  \tn
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{3.833cm}}{- an array is a mutable, fixed-length, constant-time-indexed sequence of values of type t \newline - new int{[}{]}\{2, 4, 6, 8\} gives you fixed size array \newline - new int{[}9{]}\{\} gives you a empty array of 9 spaces with null or 0 \newline - uses length function \newline - mutability (intArray{[}3{]} = 17;) means int at index 3 is now 17 \newline - assertArrayEquals} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}


% That's all folks
\end{multicols*}

\end{document}