kotlin constructors

a folder in which the war package will contain all dependent libraries (Java project depends on the most of the library is a jar package)In addition, I added the following in my gradle configuration file:apply plugin: "war"apply plugin: ‘application‘mainClassName = ‘com.ysl.jna.JnaApplicationKt‘(At the moment I don't know if it really works)The packaged operation is done here after you can choose the form you want to pack (or both forms of the package) after the package is finished, you will fi

Introduction to common operators and usages appearing in Kotlin . Operator Indicates that this object may be empty Add a question mark after the variable type, representing the variable as a nullable variable var name:string? = "Zhangsan" /** * If Str cannot be converted to INT type, then return null /Fun parseint (str:string): Int? { //(code slightly) } B?. Length//If B is non-null, return b.length, otherwise null, the type of the express

Kotlin commonly used operator 1, Elvis operator?: If the left expression is not empty, the Elvis operator returns the result on the left, otherwise it returns the result on the right.Note that the expression on the right only evaluates when the left side is empty Val a = b?. Length?:-1 //equivalent to: val a:int = if (b!= null) B.length else-12, safe conversion as? When using as transformation, classcastexception may often appear. So, now you can ma

Java. var and Val all member variables (including defined in the class and directly defined in the KT file) must be initialized when defined, and local variables (defined within the method) can be uninitialized. Such as: var s:string? = null var s2:string = "" Fun Main (args:arrayS,s2,test three variables in the above code must be initialized, but not m is not required. var: defines a variable variable. Val: Defining constants, the defined variables are final types. such as

Control Flow If expression In Kotlin, if is an expression that has a return value. But does not support three mesh operations Val A = 1 val b = 2 var max = a if (a If the if branch is a block of code, the last expression of the code block defaults to the return value Val max4 = if (a > B) { print ("Choose a") a } else { print ("Choose B") b } If an if expression returns a result or if an if expres

Arrays are represented by arrayThere are three ways to initialize a number group:var = arrayof (array1:arrayvar array2:arrayvar array3:arrayKotlin also has a specialized class with no boxing overhead to represent arrays of native types: ByteArray, Shortarray, Intarray, and so on. These classes and arrays have no inheritance relationships, but they have the same set of method properties.The array type of the basic type of Kotlin (number, character, Boo

parameter, but it is not the first parameter. When called, the parameter B is assigned by means of the parameter name = value, otherwise the assigned value is passed to the variable parameter a. To turn on the class of the KT file above, you can find that the corresponding Java code for this function is as follows: As you can see, variable parameter A has become a string array. Generic type Specify the generic type by Fun Main (args:arrayThis functionality is equivalent to extending the funct

When testing the Kotlin, we need a main function entry that is the same as the Java language, so be careful how you create it. Right-click Select the File type when you create a new item here.When you click OK, you create a. kt file that basically has nothing but a package xx.Then enter main return, the final generated main function: Fun Main (args:array After generating the main function, we can create the class directly in the current. kt file

This is a article on constructors in C # for the beginner level programmers. It covers simple constructors, constructors overloading, behaviour of constructors in inheritance, constructor chaining D Static Constructors. At the "End", it contains the general FAQs about

A. Overview of constructors in C # :C # the middle class contains data members and function members. Function members provide some functionality for manipulating data in classes, including methods, properties, constructors, and finalizers, operators, and indexers. 1. definition of constructor design :A constructor is a special method that allows an instance of a type to be initialized to a good state.2

Literals and constructorsThe literal patterns in JavaScript are more concise, expressive, and are not prone to error when defining objects. This chapter discusses literals, including objects, arrays, and regular expression literals, and why literals are better than equivalent built-in constructors (such as Object() , Array() etc.). This chapter also describes the JSON format, which is a data interchange format defined using the form of arrays and obje

to cause the object to fail, a Std::bad_alloc exception is thrown, and the "new" Operation never returns NULLPTR. On the other hand, the C + + language also guarantees that if the pointer P is a nullptr, then "delete P" does nothing and naturally there will be no error. Therefore, there is no need to check the validity of pointers before using "new" to create objects and the "delete" keyword before destroying them, so it is good to use them directly.// Creating Objects New Teacher (); // use po