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![Structured Bindings
std::tuple<int, int> point();
auto [x, y] = point();
@pati_gallardo](https://image.slidesharecdn.com/javazone2017-170913091216/75/C-for-Java-Developers-JavaZone-2017-37-2048.jpg)
![Lambda and Captures
auto meaning = [](){ return 42; }
auto life = 42;
auto meaning = [life]() { return life; }
auto meaning = [=]() { return life; }
auto meaning = [&]() { life++; return life;}
@pati_gallardo](https://image.slidesharecdn.com/javazone2017-170913091216/75/C-for-Java-Developers-JavaZone-2017-38-2048.jpg)
{
return i == 42;
});
@pati_gallardo](https://image.slidesharecdn.com/javazone2017-170913091216/75/C-for-Java-Developers-JavaZone-2017-61-2048.jpg)
Uploaded byPatricia Aas
C++ for Java Developers (JavaZone 2017)
The document is a presentation on C++ for Java developers. It introduces C++ concepts like classes, references, pointers, memory management and standard libraries. It emphasizes using modern C++ features like the stack instead of heap for memory, values instead of pointers, and standard libraries. It summarizes that developers should use modern C++ practices like values, references, const, and libraries, but most importantly not use raw pointers like "Banana * b = new Banana();".
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C++ for Java Developers (JavaZone 2017)
- 1.
- 2. C++ for JavaDevelopers Android Edition Patricia Aas JavaZone 2017 @pati_gallardo
- 3.
- 4. Patricia Aas Programmer -mainly in C++ Currently : Vivaldi Technologies Previously : Cisco Systems, Knowit, Opera Software Master in Computer Science - main language Java Twitter : @pati_gallardo
- 5. What Do IWant You To Remember? @pati_gallardo
- 6. Don’t do This! Banana* b = new Banana(); EVER @pati_gallardo
- 7. Why Should YouCare? @pati_gallardo
- 8. Portable Languages Tools ofthe Trade Java JavaScript Python C++ @pati_gallardo
- 9. "Here be dragons"@pati_gallardo
- 10. Interesting Parts ofAndroid @pati_gallardo
- 11. SurfaceFlinger The Compositor Composes thefinal frame of Android Which consists of many surfaces from many clients @pati_gallardo
- 12. Binder IPC Mechanism around whichAndroid is built Requires kernel support Does context switch on IPC calls @pati_gallardo
- 13. Zygote Prototype App process UsesLinux features to isolate apps and use memory efficiently @pati_gallardo
- 14. Let’s Learn someModern C++ (11-17) @pati_gallardo
- 15.
- 16. Your First Object #include"Banana.h" int main() { Banana b; } @pati_gallardo
- 17.
- 18. Your First Program #include<iostream> #include <string> int main() { std::string s("Hello "); std::cout << s << "World!"; } @pati_gallardo
- 19. Includes - JavaImport Including your own headers #include "Banana.h" Including library headers #include <string> @pati_gallardo
- 20. Namespaces - JavaPackages namespace fruits { class Banana { }; } @pati_gallardo
- 21. fruits::Banana b; using namespacefruits; Banana b; Using namespace - Java Import static @pati_gallardo
- 22. Using Namespace #include <iostream> #include<string> using namespace std; int main() { string s("Hello World!"); cout << s; } @pati_gallardo
- 23. Values, Objects andReferring to them @pati_gallardo
- 24. Anything Can Bea Value int main() { Banana b; int meaning = 42; auto pi { 3.14 } std::string s = "Hi!"; std::mutex my_mutex; } @pati_gallardo
- 25. Referring to Things ●Reference ● Pointer ● Value @pati_gallardo
- 26. C++ Reference & AC++ reference is not a Java pointer It has to reference an object It is never null It can never reference another object SAFE : Banana & b @pati_gallardo
- 27. C++ Pointer * AC++ pointer is not a Java pointer It’s often called a “Raw Pointer” It’s a raw memory address UNSAFE : Banana * b @pati_gallardo
- 28. C++ Value In C++everything is a value, even objects When passed by value it is COPIED* Can only pass-by-value if copying is supported* SAFE : Banana b * Sometimes the original value can be reused @pati_gallardo
- 29. Range based For vector<Banana>bananas; for (auto & banana : bananas) cout << banana; @pati_gallardo
- 30. Const : TheMany Meanings ● Object ● Function ● Local variable ● Member ● Pointer @pati_gallardo
- 31. const - Relatedto Final Variables in Java More things can be const than can be final Java : final Banana ptr; // ptr is final C++: Banana * const ptr; // ptr is const C++: const Banana * ptr; // object is const C++: const Banana * const ptr; // object & ptr is const @pati_gallardo
- 32. Immutable View OfAn OBJECT const Banana & banana; But the object is mutable - just not by you Mark functions that don’t mutate as const @pati_gallardo
- 33. Parameter Passing, ReturnValues & Lambdas @pati_gallardo
- 34. Parameter Passing Pass byconst ref : const Banana & banana Pass by reference : Banana & banana Pass by value : Banana banana Pass by pointer - be very careful @pati_gallardo
- 35. Auto return type automeaning() { return 42; } @pati_gallardo
- 36. Return by Value Bananafruit() { return Banana(); } @pati_gallardo
- 37. Structured Bindings std::tuple<int, int>point(); auto [x, y] = point(); @pati_gallardo
- 38. Lambda and Captures automeaning = [](){ return 42; } auto life = 42; auto meaning = [life]() { return life; } auto meaning = [=]() { return life; } auto meaning = [&]() { life++; return life;} @pati_gallardo
- 39. Memory : Lifetime& Ownership @pati_gallardo
- 40. Where is it? Stack Bananab; Heap auto b = make_unique<Banana>(); Banana * b = new Banana(); @pati_gallardo
- 41. Stack - Similarto “Try With Resources” Destroyed when exiting scope Deterministic Garbage Collection @pati_gallardo
- 42. Loving the Stack #include<iostream> #include <string> using namespace std; int main() { { string s("Hello World!"); cout << s; } // <- GC happens here! } @pati_gallardo
- 43. Hold a Valueon the Stack that Controls The Lifetime of Your Heap Allocated Object using namespace std; auto myBanana = make_unique<Banana>(); auto ourBanana = make_shared<Banana>(); Smart Pointers @pati_gallardo
- 44.
- 45. Class Declaration inHeader File Class Definition in Cpp File Banana.h & Banana.cpp A header is similar to an interface Function declarations Member variables @pati_gallardo
- 46.
- 47. No Explicit RootSuperclass Implicitly defined member functions Don’t redefine them if you don’t need to The defaults are good Rule-of-zero (Zero except for the constructor) @pati_gallardo
- 48. class B { public: // Constructor B(); //Destructor ~B(); // Copy constructor B(const B&); // Copy assignment op B& operator=(const B&); // Move constructor B(B&&); // Move assignment op B& operator=(B&&); }; Implicitly Defined Functions @pati_gallardo
- 49. All Classes AreFinal by Default By extension : All methods are final by default @pati_gallardo
- 50. Virtual Functions Pure virtual- Interface virtual void bootFinished() = 0; Use override void bootFinished() override; @pati_gallardo
- 51. Multiple Inheritance isAllowed Turns out the ‘Diamond Problem’ is mostly academic ( and so is inheritance ;) ) @pati_gallardo
- 52. All Classes Are“Abstract” Interface : only pure virtual methods Abstract Class : some pure virtual methods Plain Old Class : no pure virtual methods @pati_gallardo
- 53. Structs A C++ Structis a Class Where all members are public by default @pati_gallardo
- 54. Static : TheMany Meanings “There can be only one” Function in cpp file Local variable in a function Member / function in a class @pati_gallardo
- 55. Static member /function in a Class Pretty much the same as Java @pati_gallardo
- 56. Static Function ina Cpp File The function is local to the file @pati_gallardo
- 57. Static Variable ina Function Global variable Only accessible in this function Same variable across calls @pati_gallardo
- 58. Containers and StandardTypes @pati_gallardo
- 59. Use std::String -never char * Or whatever string your project uses :D @pati_gallardo
- 60. Std::Vector Is Great std::vectorhas great performance Don’t use raw arrays Prefer std::vector or std::array @pati_gallardo
- 61. Use std::Algorithms using namespacestd; vector<int> v { 1337, 42, 256 }; auto r = find_if(begin(v), end(v), [](int i){ return i == 42; }); @pati_gallardo
- 62. The Standard Library& co @pati_gallardo
- 63. Many Common Libraries TheStandard Library Boost (Pre-Standard) Qt (Gui and Portable) ++ Use the Libraries @pati_gallardo
- 64.
- 65. Do Modern C++ Usethe Stack Use Values Use References Use Const Use the Libraries But Most Importantly... What to Remember @pati_gallardo
- 66. Don’t do This! Banana* b = new Banana(); EVER @pati_gallardo
- 67. #include "Banana.h" int main() { Bananab; } @pati_gallardo
- 68. Make Everyone FeelSafe To Be Themselves @pati_gallardo
- 69. C++ for JavaDevelopers Android Edition Patricia Aas, Vivaldi Technologies @pati_gallardo Photos from pixabay.com
- 70. Vivaldi Swag Patricia Aas,Vivaldi Technologies @pati_gallardo Photos from pixabay.com