\documentclass[10pt,a4paper]{article}

% Packages
\usepackage{fancyhdr}           % For header and footer
\usepackage{multicol}           % Allows multicols in tables
\usepackage{tabularx}           % Intelligent column widths
\usepackage{tabulary}           % Used in header and footer
\usepackage{hhline}             % Border under tables
\usepackage{graphicx}           % For images
\usepackage{xcolor}             % For hex colours
%\usepackage[utf8x]{inputenc}    % For unicode character support
\usepackage[T1]{fontenc}        % Without this we get weird character replacements
\usepackage{colortbl}           % For coloured tables
\usepackage{setspace}           % For line height
\usepackage{lastpage}           % Needed for total page number
\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{Philip Schmid (Higarigh)}
\pdfinfo{
  /Title (oov1.pdf)
  /Creator (Cheatography)
  /Author (Philip Schmid (Higarigh))
  /Subject (OOv1 Cheat Sheet)
}

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% This two commands together give roughly
% the right line height in the tables
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% Commands
\newcommand{\SetRowColor}[1]{\noalign{\gdef\RowColorName{#1}}\rowcolor{\RowColorName}} % Shortcut for row colour
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% Font and Colours
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\renewcommand{\familydefault}{\sfdefault}
\color{TextColor}

% Header and Footer
\pagestyle{fancy}
\fancyhead{} % Set header to blank
\fancyfoot{} % Set footer to blank
\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}}
    }
\end{tabulary}
\columnbreak
\begin{tabulary}{11cm}{L}
    \vspace{-2pt}\large{\bf{\textcolor{DarkBackground}{\textrm{OOv1 Cheat Sheet}}}} \\
    \normalsize{by \textcolor{DarkBackground}{Philip Schmid (Higarigh)} via \textcolor{DarkBackground}{\uline{cheatography.com/20304/cs/3111/}}}
\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}Philip Schmid (Higarigh) \\
  \uline{cheatography.com/higarigh} \\
  \end{tabulary}
\vfill
\columnbreak
\begin{tabulary}{5.8cm}{L}
  \SetRowColor{FootBackground}
  \mymulticolumn{1}{p{5.377cm}}{\bf\textcolor{white}{Cheat Sheet}}  \\
   \vspace{-2pt}Published 25th January, 2015.\\
   Updated 12th May, 2016.\\
   Page {\thepage} of \pageref{LastPage}.
\end{tabulary}
\vfill
\columnbreak
\begin{tabulary}{5.8cm}{L}
  \SetRowColor{FootBackground}
  \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}
\raggedright
\raggedcolumns

% Set font size to small. Switch to any value
% from this page to resize cheat sheet text:
% www.emerson.emory.edu/services/latex/latex_169.html
\footnotesize % Small font.

\begin{multicols*}{3}

\begin{tabularx}{5.377cm}{x{1.54287 cm} x{3.43413 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{Java basics}}  \tn
% Row 0
\SetRowColor{LightBackground}
`x = a ? b : c` & a true? x = b, a false? x = c \tn 
% Row Count 2 (+ 2)
% Row 1
\SetRowColor{white}
`0.1 + 0.1 == 0.3` & False, workaround: `Math.abs(0.1 + 0.1) \textless{} 0.2e6` \tn 
% Row Count 4 (+ 2)
% Row 2
\SetRowColor{LightBackground}
`a \&\& b` & Only check b if a is true \tn 
% Row Count 5 (+ 1)
% Row 3
\SetRowColor{white}
`a || b` & Only check b if a is false \tn 
% Row Count 6 (+ 1)
% Row 4
\SetRowColor{LightBackground}
`0b11001` & binary, leading "0b" \tn 
% Row Count 7 (+ 1)
% Row 5
\SetRowColor{white}
`0x1e` & hexadecimal, leading "0x" \tn 
% Row Count 8 (+ 1)
% Row 6
\SetRowColor{LightBackground}
`010 != 10` & Leading 0 means octal \tn 
% Row Count 9 (+ 1)
% Row 7
\SetRowColor{white}
`'A' == 'a'` & False (case sensitive) \tn 
% Row Count 10 (+ 1)
% Row 8
\SetRowColor{LightBackground}
`'A'  \textless{}  'B'` & True \tn 
% Row Count 12 (+ 2)
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\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{p{0.74655 cm} x{4.23045 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{Java primitive data types}}  \tn
% Row 0
\SetRowColor{LightBackground}
\seqsplit{boolean} & true, false \tn 
% Row Count 2 (+ 2)
% Row 1
\SetRowColor{white}
char & 16 bit, UTF-16 \tn 
% Row Count 3 (+ 1)
% Row 2
\SetRowColor{LightBackground}
byte & 8 bit, -128...127 \tn 
% Row Count 4 (+ 1)
% Row 3
\SetRowColor{white}
short & 16 bit, -32.768 ... 32.767 \tn 
% Row Count 5 (+ 1)
% Row 4
\SetRowColor{LightBackground}
int & 32 bit, -2\textasciicircum{}31\textasciicircum{} to +2\textasciicircum{}31\textasciicircum{}-1 \tn 
% Row Count 6 (+ 1)
% Row 5
\SetRowColor{white}
long & 64 bit, -2\textasciicircum{}63\textasciicircum{} to +2\textasciicircum{}63\textasciicircum{}-1,`long x = 100l;` \tn 
% Row Count 8 (+ 2)
% Row 6
\SetRowColor{LightBackground}
float & 32 bit, `float x = 100f;` \tn 
% Row Count 9 (+ 1)
% Row 7
\SetRowColor{white}
\seqsplit{double} & 64 bit, `double x = 100d;` \tn 
% Row Count 10 (+ 1)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
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\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Java type casting}}  \tn
\SetRowColor{LightBackground}
\mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/higarigh_1419424860_Cast_overview.png}}} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{red arrows =implizit (probably information loss due inaccurate dataformat) \newline black arrows = explizit cast (heavy information loss possible -{}-\textgreater{} developer)}  \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
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\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{X}
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\mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Java interfaces}}  \tn
% Row 0
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\mymulticolumn{1}{x{5.377cm}}{Methods in intefaces are implicitly public and abstract and can't be private.} \tn 
% Row Count 2 (+ 2)
% Row 1
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\mymulticolumn{1}{x{5.377cm}}{Only constant variables are allowed: `public static final int HIGHWAY\_MIN\_SPEED = 60;` "public static final" is optional.} \tn 
% Row Count 5 (+ 3)
% Row 2
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\mymulticolumn{1}{x{5.377cm}}{Same named methods in basic interface and super interface must have the same return type.} \tn 
% Row Count 7 (+ 2)
% Row 3
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\mymulticolumn{1}{x{5.377cm}}{Same named variables in basic interface and super interface can have different return types.} \tn 
% Row Count 9 (+ 2)
% Row 4
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\mymulticolumn{1}{x{5.377cm}}{Default methods: Basic interface doesn't have to implement default methods. If one method is not overriden, it just takes the default method.} \tn 
% Row Count 12 (+ 3)
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\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{x{2.4885 cm} x{2.4885 cm} }
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\mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{Java reference types}}  \tn
% Row 0
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`int{[}{]} x = new int{[}10{]};` & normal Array (`public int{[}{]} x(int{[}{]} y)\{return z\}`) \tn 
% Row Count 3 (+ 3)
% Row 1
\SetRowColor{white}
`int{[}{]}{[}{]} m = new int{[}2{]}{[}3{]};` & 2 dimensional array \tn 
% Row Count 5 (+ 2)
% Row 2
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`Arrays.equals(a, b)` & Compare array content \tn 
% Row Count 7 (+ 2)
% Row 3
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\seqsplit{`Arrays.deepEquals(a}, b)` & Compare x dimensional array \tn 
% Row Count 9 (+ 2)
% Row 4
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`public enum Weekday\{ MONDAY, ..., SUNDAY \}` & Enum \tn 
% Row Count 12 (+ 3)
% Row 5
\SetRowColor{white}
`String a = "Prog1";` & new reference to String-Object "Prog1" (if already exists, otherwise create it) \tn 
% Row Count 16 (+ 4)
% Row 6
\SetRowColor{LightBackground}
`String c = new String("Prog1");` & new String-Object \tn 
% Row Count 18 (+ 2)
% Row 7
\SetRowColor{white}
`a.equals(b)` & Compare Strings \tn 
% Row Count 19 (+ 1)
% Row 8
\SetRowColor{LightBackground}
\mymulticolumn{2}{x{5.377cm}}{`StringBuilderbuilder = new StringBuilder("Hi"); builder.append(" you!"); builder.insert(0, "XY"); String text= builder.toString();`} \tn 
% Row Count 22 (+ 3)
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\mymulticolumn{1}{x{5.377cm}}{@Override  \newline 	public boolean equals(Object obj) \{  \newline 	~	if (obj == null) \{  \newline 			~~~~return false;  \newline 	~	\} else if (getClass() != obj.getClass()) \{ \newline 			~~~~return false; \newline 	~	\} else if (!super.equals(obj)) \{  \newline 			~~~~return false; \newline 	~	\} else \{ \newline 			~~~~Student other = (Student)obj; return regNumber == other.regNumber;  \newline 	~	\} \newline 	\}} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{If equals() is changed, hashCode() has also be changed! x.equals(y) -\textgreater{} x.hashCode() == y.hashCode()}  \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
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\begin{tabularx}{5.377cm}{x{1.14471 cm} x{3.83229 cm} }
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\mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{Keywords}}  \tn
% Row 0
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public & can be seen by all that imports this package \tn 
% Row Count 2 (+ 2)
% Row 1
\SetRowColor{white}
\seqsplit{protected} & can be seen by all classes in this package and all subclasses of this \tn 
% Row Count 5 (+ 3)
% Row 2
\SetRowColor{LightBackground}
package & can be seen by all classes in this package \tn 
% Row Count 7 (+ 2)
% Row 3
\SetRowColor{white}
private & can be seen only by this class \tn 
% Row Count 8 (+ 1)
% Row 4
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static & only once for all instances of this class \tn 
% Row Count 10 (+ 2)
% Row 5
\SetRowColor{white}
final & can only be defined once and not changed later. Class: no subclasses, Method: no overriding \tn 
% Row Count 14 (+ 4)
% Row 6
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static final & Means this is a constant \tn 
% Row Count 16 (+ 2)
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\mymulticolumn{3}{x{5.377cm}}{\bf\textcolor{white}{Javadoc}}  \tn
% Row 0
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Start with /** & end with */ & each line * \tn 
% Row Count 2 (+ 2)
% Row 1
\SetRowColor{white}
@author name & author & class / \seqsplit{interface} \tn 
% Row Count 4 (+ 2)
% Row 2
\SetRowColor{LightBackground}
@version number & version & class / \seqsplit{interface} \tn 
% Row Count 6 (+ 2)
% Row 3
\SetRowColor{white}
@param name description & parameter & method \tn 
% Row Count 8 (+ 2)
% Row 4
\SetRowColor{LightBackground}
@return description & \seqsplit{returnvalue} & method \tn 
% Row Count 9 (+ 1)
% Row 5
\SetRowColor{white}
@throws/@exception type description & potential exception & method \tn 
% Row Count 11 (+ 2)
% Row 6
\SetRowColor{LightBackground}
@deprecated description & deprecated (outdated) & method \tn 
% Row Count 13 (+ 2)
\hhline{>{\arrayrulecolor{DarkBackground}}---}
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\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Java hashcode() example}}  \tn
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{public int hashCode() \{ \newline ~~~~return firstName.hashCode() + 31 * surName.hashCode(); \newline \}} \tn 
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\begin{tabularx}{5.377cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Java compareTo example}}  \tn
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{class Person implements Comparable\textless{}Person\textgreater{} \{ \newline 	~	private String firstName, lastName;  \newline 	~	// Constructor…  \newline 	~	@Override  \newline 	~	public int compareTo(Person other) \{ \newline 	~~~~		int c = compareStrings(lastName, other.lastName); \newline 	~~~~		if (c != 0) \{ return c; \} \newline 	~~~~		else \{ return compareStrings(firstName, other.firstName); \} \newline 		~\}  \newline 		private int compareStrings(String a, String b) \{ \newline 		~	if (a == null) \{ return b == null ? 0 : 1; \} \newline 		~	else \{ return a.compareTo(b); \} \newline 		~~\} \newline 	\}} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{x{2.4885 cm} x{2.4885 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{Java collections}}  \tn
% Row 0
\SetRowColor{LightBackground}
`ArrayList\textless{}Object\textgreater{} a1 = new ArrayList\textless{}\textgreater{}();` & `get(int), set(int, "OO"), add("CN2"), remove(int), remove("CN1"), contains("CN1"), size()` \tn 
% Row Count 5 (+ 5)
% Row 1
\SetRowColor{white}
`LinkedList\textless{}Object\textgreater{} l1 = new LinkedList\textless{}\textgreater{}();` & `add("ICTh"), add(int, "Bsys1"), remove(int), remove("ICTh"), contains("ICTh")` \tn 
% Row Count 9 (+ 4)
% Row 2
\SetRowColor{LightBackground}
`Set\textless{}String\textgreater{} s1= new TreeSet\textless{}\textgreater{}();` or `Set\textless{}String\textgreater{} s2= new HashSet\textless{}\textgreater{}();` & `add("Test"), remove("Test"), size()` checks if already added -\textgreater{} if so, return false. TreeSet = sorted, always efficient. HashSet = unsorted, usually very efficient \tn 
% Row Count 18 (+ 9)
% Row 3
\SetRowColor{white}
`Map\textless{}Integer, Object\textgreater{} m1= new HashMap\textless{}\textgreater{}();` or `Map\textless{}Integer, Object\textgreater{} m2= new TreeMap\textless{}\textgreater{}();` & `get(key), put(key, "Test"), remove(key), containsKey(key), size(),` TreeMap = sorted by key, always efficient. HashMap = unsorted, usually very efficient \tn 
% Row Count 26 (+ 8)
% Row 4
\SetRowColor{LightBackground}
\mymulticolumn{2}{x{5.377cm}}{`Iterator\textless{}String\textgreater{} it= m1.iterator(); while(it.hasNext()) \{..\}`} \tn 
% Row Count 28 (+ 2)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{x{2.4885 cm} x{2.4885 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{Java inheritance}}  \tn
% Row 0
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`Vehicle v1 = new Car();` & {\bf{Vehicle = static type, Car = dynamic type}} \tn 
% Row Count 3 (+ 3)
% Row 1
\SetRowColor{white}
`Object o = new Vehicle(); Vehicle v = (Vehicle)o;` & Vaild -\textgreater{} Down-Cast: Static type can be down casted \tn 
% Row Count 6 (+ 3)
% Row 2
\SetRowColor{LightBackground}
`Vehicle v = new Vehicle; Car c = (Car)v;` & Error -\textgreater{} Dynamic type can't be down casted \tn 
% Row Count 9 (+ 3)
% Row 3
\SetRowColor{white}
`if(v instanceof Car) \{ Car c = (Car)v;\}` & Test if dynamic type matches static type \tn 
% Row Count 12 (+ 3)
% Row 4
\SetRowColor{LightBackground}
`super.variable` & Hiding: variable from super class \tn 
% Row Count 14 (+ 2)
% Row 5
\SetRowColor{white}
\seqsplit{`((SuperSuperClass)this)}.variable` & Hiding: variable from "super.super" class \tn 
% Row Count 17 (+ 3)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\SetRowColor{LightBackground}
\mymulticolumn{2}{x{5.377cm}}{{\bf{Dynamic dispatch}}: Methods: from dynamic typ and variables from static type.}  \tn 
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\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{x{2.63781 cm} x{2.33919 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{Java Lambdas / Stream API}}  \tn
% Row 0
\SetRowColor{LightBackground}
\seqsplit{`Collections.sort(people}, (p1, p2) -\textgreater{} p1.getAge() –p2.getAge());` & sort ascending by age \tn 
% Row Count 4 (+ 4)
% Row 1
\SetRowColor{white}
\seqsplit{`Collections.sort(people}, (p1, p2) -\textgreater{} \seqsplit{p1.getLastName().compareTo(p2.getLastName()));`} & sort by lastname \tn 
% Row Count 9 (+ 5)
% Row 2
\SetRowColor{LightBackground}
\seqsplit{`people.stream().filter(p} -\textgreater{} p.getAge() \textgreater{}= 18) .map(p -\textgreater{} p.getLastName()) .sorted() \seqsplit{.forEach(System.out::println);`} & stream API example \tn 
% Row Count 15 (+ 6)
% Row 3
\SetRowColor{white}
`people.stream() .filter(p -\textgreater{} \seqsplit{p.getLastName().contains(pattern))} .forEach(System.out::println);` & `pattern` has to be final! \tn 
% Row Count 20 (+ 5)
% Row 4
\SetRowColor{LightBackground}
`Random random= newRandom(4711); \seqsplit{Stream.generate(random::nextInt)} .forEach(System.out::println);` & generate random stream \tn 
% Row Count 25 (+ 5)
% Row 5
\SetRowColor{white}
`List\textless{}Person\textgreater{} list= \seqsplit{peopleStream.collect(Collectors.toList());`} & stream to collection (List/Set/Map) \tn 
% Row Count 28 (+ 3)
% Row 6
\SetRowColor{LightBackground}
`Person{[}{]} array= peopleStream.toArray(length-\textgreater{} newPerson{[}length{]});` & stream to array \tn 
% Row Count 32 (+ 4)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\SetRowColor{LightBackground}
\mymulticolumn{2}{x{5.377cm}}{Possible Stream API operations: `filter(Predicate), map(Function), mapToInt(Function), mapToDouble(Function), sorted(), distinct(), limit(long n), skip(long n), count(), min(), max(), average(), sum()`}  \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Comparator \& Methodreference}}  \tn
% Row 0
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{Inferface used to compare 2 Objects(before you used lamdas).} \tn 
% Row Count 2 (+ 2)
% Row 1
\SetRowColor{white}
\mymulticolumn{1}{x{5.377cm}}{Contains the method `public int compare(T o1, T o2)` which you need to override. Returns positiv number if o1 is bigger then o2 and negative if oppisite 0 means that they are equal} \tn 
% Row Count 6 (+ 4)
% Row 2
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{Instead of a comparator use methodrefernce class:methodName eg \seqsplit{`PersonComp::compareName`}} \tn 
% Row Count 8 (+ 2)
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Nested class}}  \tn
% Row 0
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{Use this if a class is only used in another class} \tn 
% Row Count 1 (+ 1)
% Row 1
\SetRowColor{white}
\mymulticolumn{1}{x{5.377cm}}{No seperate classfile} \tn 
% Row Count 2 (+ 1)
% Row 2
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{The inner class can use all members of the outer class (this include private members)} \tn 
% Row Count 4 (+ 2)
% Row 3
\SetRowColor{white}
\mymulticolumn{1}{x{5.377cm}}{Instantiation from outside eg `Polygon.Pointpoint= myPolygon.newPoint();`} \tn 
% Row Count 6 (+ 2)
% Row 4
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{Can be declared in a method -\textgreater{} All variables from outside are getting final  eg `Car getSuperCar() \{ class SuperCar extends Car \{ @Override public int getMaxSpeed() \{return 300; \} \} return newSuperCar();\}`} \tn 
% Row Count 11 (+ 5)
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Java own exception class}}  \tn
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{public class MyException extends Exception \{ \newline ~private static final long serialVersionUID = 1L;  \newline ~public MyException(String msg) \{ \newline ~~		super(msg); \newline ~\} \newline \}} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Java package import conflict order}}  \tn
\SetRowColor{white}
\mymulticolumn{1}{x{5.377cm}}{1. own class (inc. nested class) \newline % Row Count 1 (+ 1)
2. single type imports -\textgreater{} `import p2.A;` \newline % Row Count 2 (+ 1)
3. type in own package -\textgreater{} `package p1; class X` \newline % Row Count 3 (+ 1)
4. Import on demand -\textgreater{} `import p2.*;`% Row Count 4 (+ 1)
} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{x{1.54287 cm} x{3.43413 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{Java regex}}  \tn
% Row 0
\SetRowColor{LightBackground}
`1*` & 0 to * \tn 
% Row Count 1 (+ 1)
% Row 1
\SetRowColor{white}
`1+` & 1 to * \tn 
% Row Count 2 (+ 1)
% Row 2
\SetRowColor{LightBackground}
`1\{2,5\}` & min 2 max 5 (11..11111) \tn 
% Row Count 3 (+ 1)
% Row 3
\SetRowColor{white}
`1\{2,\}` & min 2 max * (11, 111, etc.) \tn 
% Row Count 4 (+ 1)
% Row 4
\SetRowColor{LightBackground}
`1\{3\}` & exactly 111 \tn 
% Row Count 5 (+ 1)
% Row 5
\SetRowColor{white}
`-?1` & -1 or 1, "-" is optional \tn 
% Row Count 6 (+ 1)
% Row 6
\SetRowColor{LightBackground}
`Mo|Di` & Or \tn 
% Row Count 7 (+ 1)
% Row 7
\SetRowColor{white}
`{[}a-z{]}` & any letter from a to z \tn 
% Row Count 8 (+ 1)
% Row 8
\SetRowColor{LightBackground}
`{[}a-zA-Z{]}` & any letter from a to z or A to Z \tn 
% Row Count 10 (+ 2)
% Row 9
\SetRowColor{white}
`\textbackslash{}s` & whitespace \tn 
% Row Count 11 (+ 1)
% Row 10
\SetRowColor{LightBackground}
`.` & anything except newline \tn 
% Row Count 12 (+ 1)
% Row 11
\SetRowColor{white}
`{[}\textasciicircum{}abc{]}` & anything except a, b or c \tn 
% Row Count 13 (+ 1)
% Row 12
\SetRowColor{LightBackground}
`\$` & end of string \tn 
% Row Count 14 (+ 1)
% Row 13
\SetRowColor{white}
`\textbackslash{}d` & any digit \tn 
% Row Count 15 (+ 1)
% Row 14
\SetRowColor{LightBackground}
`\textbackslash{}D` & not digit \tn 
% Row Count 16 (+ 1)
% Row 15
\SetRowColor{white}
`(?\textless{}Group1\textgreater{}REGEX)` & name capture group -\textgreater{} `String Part1 = \seqsplit{matcher.group("Group1");`} \tn 
% Row Count 19 (+ 3)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\SetRowColor{LightBackground}
\mymulticolumn{2}{x{5.377cm}}{Example: Check daytime: `({[}0-1{]}?{[}0-9{]}|2{[}0-3{]}):{[}0-5{]}{[}0-9{]}`}  \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Java regex code example}}  \tn
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{String input = scanner.nextLine(); \newline Pattern pattern = Pattern.compile("({[}0-2{]}?{[}0-9{]}):({[}0-5{]}{[}0-9{]})"); \newline Matcher matcher = pattern.matcher(input); \newline if (matcher.matches()) \{ \newline ~~String hoursPart = matcher.group(1); \newline ~~String minutesPart = matcher.group(2); \newline ~~System.out.println(..); \newline \}} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{x{2.4885 cm} x{2.4885 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{Java JUnit}}  \tn
% Row 0
\SetRowColor{LightBackground}
\seqsplit{`assertEquals(expected}, actual)` & actual «equals» expected \tn 
% Row Count 2 (+ 2)
% Row 1
\SetRowColor{white}
\seqsplit{`assertSame(expected},actual)` & actual== expected (only reference comparation) \tn 
% Row Count 5 (+ 3)
% Row 2
\SetRowColor{LightBackground}
\seqsplit{`assertNotSame(expected}, actual)` & expected != actual (only reference comparation) \tn 
% Row Count 8 (+ 3)
% Row 3
\SetRowColor{white}
\seqsplit{`assertTrue(condition)`} & condition \tn 
% Row Count 10 (+ 2)
% Row 4
\SetRowColor{LightBackground}
\seqsplit{`assertFalse(condition)`} & !condition \tn 
% Row Count 12 (+ 2)
% Row 5
\SetRowColor{white}
`assertNull(value)` & value== null \tn 
% Row Count 13 (+ 1)
% Row 6
\SetRowColor{LightBackground}
\seqsplit{`assertNotNull(value)`} & value!= null \tn 
% Row Count 15 (+ 2)
% Row 7
\SetRowColor{white}
`fail()` & everytime false \tn 
% Row Count 16 (+ 1)
% Row 8
\SetRowColor{LightBackground}
`@Test(timeout= 5000)` & set test timeout \tn 
% Row Count 18 (+ 2)
% Row 9
\SetRowColor{white}
`@Test(expected= \seqsplit{IllegalArgumentException}.class)` & expect exception, if exception is thrown, test passes \tn 
% Row Count 21 (+ 3)
% Row 10
\SetRowColor{LightBackground}
`@Before public void setUp() \{ … \}` & run this before each test \tn 
% Row Count 23 (+ 2)
% Row 11
\SetRowColor{white}
`@After public void tearDown() \{ … \}` & run this after each test \tn 
% Row Count 25 (+ 2)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Java JUnit examples}}  \tn
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{@Test \newline publicvoidtestPrime\_2() \{ \newline ~~assertTrue("2 isprime", utils.isPrime(2)); \newline \}} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Java generics}}  \tn
% Row 0
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{Example: `class Node\textless{}T extends Number \& Serializable\textgreater{}\{ … \} Node\textless{}Integer\textgreater{} n1; // OK Node\textless{}Number\textgreater{} n1; // OK Node\textless{}String\textgreater{} n2; // ERROR` You can add different Interfaces with \& to ensure other functionality like serializable} \tn 
% Row Count 5 (+ 5)
% Row 1
\SetRowColor{white}
\mymulticolumn{1}{x{5.377cm}}{Wildcard type: `Node\textless{}?\textgreater{} undefinedNode; undefinedNode = new Node\textless{}Integer\textgreater{}(4); undefinedNode= new Node\textless{}String\textgreater{}("Hi!");` No read (`.getValue()`) and write (`.setValue(X)`) is allowed} \tn 
% Row Count 9 (+ 4)
% Row 2
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{static variables with generics NOT allowed eg static T maxSpeed;} \tn 
% Row Count 11 (+ 2)
% Row 3
\SetRowColor{white}
\mymulticolumn{1}{x{5.377cm}}{Generic Method: `public \textless{}T\textgreater{} T majority(T x, Ty, T z)\{ if(x.equals(y)) \{ returnx; \} if(x.equals(z)) \{ returnx; \} if(y.equals(z)) \{ return y; \} return null; \}` Call: `Double d = test.\textless{}Double\textgreater{}majority(1.0, 3.141, 1.0);` but also: `int i = majority(1,1,3);` called type inference(also possible to mix types of argument)} \tn 
% Row Count 18 (+ 7)
% Row 4
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{Rawtype: like you would insert Object -\textgreater{} you need to down cast the elements. e.g. `Node n; //without class n = new Node("Hi"); String s = (String)n.getValue();`} \tn 
% Row Count 22 (+ 4)
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Serializable}}  \tn
% Row 0
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{Is a marker interface (is empty, just says that this class supports it)} \tn 
% Row Count 2 (+ 2)
% Row 1
\SetRowColor{white}
\mymulticolumn{1}{x{5.377cm}}{Use it to say the developer that he can serialize objects of this class, which means he can write then in a bitecode and export them. Always serialize all the objects contained in the mainobject} \tn 
% Row Count 6 (+ 4)
% Row 2
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{Use serialVersionUID to identify your class (normally generated number) `private static final long serialVersionUID= -6583929648459736324L;`} \tn 
% Row Count 9 (+ 3)
% Row 3
\SetRowColor{white}
\mymulticolumn{1}{x{5.377cm}}{Example:`OutputStream fos= new \seqsplit{FileOutputStream("serial.bin")} try (ObjectOutputStream stream = new ObjectOutputStream(fos)) \{ \seqsplit{stream.writeObject(person);} \}`} \tn 
% Row Count 13 (+ 4)
% Row 4
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{Example:`InputStream fis= new \seqsplit{FileInputStream("serial.bin")} try (ObjectInputStream stream = new ObjectInputStream(fis)) \{ Person p = \seqsplit{(Person)stream.readObject();} … \}`} \tn 
% Row Count 17 (+ 4)
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Java clone() method}}  \tn
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{public Department clone() throws Exception \{ \newline ~Department d = new Department(); \newline ~d.name = name; \newline ~d.people = people; \newline ~d.subDepartments = new ArrayList\textless{}\textgreater{}(); \newline ~for (Department subD : subDepartments) \{ \newline ~~d.subDepartments.add(subD.clone()); \newline \} \newline ~return d; \newline \}} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}


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

\end{document}