final | 易学教程

Groovy closure not work with static final field from super class

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问题 class Parent { final static String newLine = "*" } class Child extends Parent{ List body = [3, 4, 5] String toString() { def str = new StringBuilder() body.each { str.append(it + newLine) } str } } def c = new Child() println c The above is one trivial sample to illustrate the problem. It couldn't be compiled using Groovy plugin on Eclipse . Remove either final or static in the field of super class solves the problem. However, I have no idea why it's the case. http://groovy.codehaus.org

Scala / PowerMockito - Java final classes causing build error in Scala Tests using Powermockito

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问题 I have a final class: public final class AClass { private final AConfig aClassConfig; public final static BeanName = "aClass" } and I'm trying to mock it in tests: @RunWith(classOf[PowerMockRunner]) @PrepareForTest(Array(classOf[AClass])) class AClassTests extends FunSuite { test("mock final class test") { val aClass = PowerMockito.mock(classOf[AClass]) assert(aClass != null) } } This causes the error: Cannot subclass final class class com.me.AClass java.lang.IllegalArgumentException: Cannot

Declaring local variable as final in a loop

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问题 I know that very similar questions have been asked and answered already, I read the ones I was able to locate and still not 100% clear. Considering this code snippet: public static void fooMethod { while(<...>) { .... final int temp = <something>; .... } } No inner classes, nothing else special or unusual. Seems counter-intuitive to me. Does declaring a local variable final in the above sample serve any purpose whatsoever? Do I understand correctly that with or without final here compiler

java中final的用法

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1.被final修饰的类无法被继承。 2.被final修饰的方法无法被重写，因为abstract修饰的方法就是用来重写的，所以final和abstract是互相矛盾的。 3.被final修饰的成员变量，其值初始化之后不可改变。（1）由于成员变量具有默认值而局部变量没有默认值，所以成员变量被final修饰时一定要赋值，不然会报错。（2）对于final修饰的成员变量，要么直接赋值，要么通过构造方法赋值，二者选其一。（3）必须保证类当中所有重载的构造方法都会对final修饰的变量赋值来源： https://www.cnblogs.com/iceywu/p/12017841.html

How do you specify variables to be final in C? [duplicate]

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问题 This question already has answers here : how const keyword works in c (6 answers) Closed 2 years ago . I am aware that it is possible to declare constants using the #define macro. With this, it would be simple to define integer, floating point or character literals to be constants. But, for more complicated data structures, such as an array, or a struct, say for example: typedef struct { int name; char* phone_number; } person; I want to be able to initialise this just once and then make it a

local variables referenced from an inner class must be final or effectively final

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问题 This program is the final assignment for my class and I'm have issues figuring out why I'm receiving the error "local variables referenced from an inner class must be final or effectively final". The program is running concurrent threads to sort an array of #'s and then find the high and low values of that array. When I created it without the concurrency, I didn't have this error. I'm struggling as to where to finalize the high and low variable. public void HiLo(int[] numbers){ int high =

The final field may not/already have been initialized [duplicate]

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问题 This question already has answers here : Closed 6 years ago . Possible Duplicate: How to handle a static final field initializer that throws checked exception In this example, I get the error The blank final field myClass may not have been initialized : private final static MyClass myClass; // <-- error static { try { myClass = new MyClass(); // <-- throws exception myClass.init(); } catch (Exception e) { // log } } In that example, I get the error The final field myClass may already have

Is there an equivalent to “sealed” or “final” in TypeScript?

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问题 I'm trying to implement a method in a super class that should be available for use, but not changeable, in sub classes. Consider this: export abstract class BaseClass { universalBehavior(): void { doStuff(); // Do some universal stuff the same way in all sub classes specializedBehavior(); // Delegate specialized stuff to sub classes } protected abstract specializedBehavior(): void; } My intention would be that any sub class of BaseClass would not only be free to omit implementation of

use mockito to stub final method [duplicate]

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问题 This question already has answers here : Final method mocking (7 answers) Closed 5 years ago . I need to use a mock who has a final method. So i use powermock but it does not work class B { public final int nb() { return 4; } } @RunWith(PowerMockRunner.class) @PrepareForTest(B.class) public class Exemple extends TestCase { @Test public void test() { B b = PowerMockito.mock(B.class); PowerMockito.when(b.nb()).thenReturn(5); final int actualState = b.nb(); assertEquals(5, actualState); } } if

java基础-final用法

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一、final关键字的含义 final在Java中可以声明成员变量、方法、类以及本地变量。一旦你将引用声明final，你将“ 不能改变 ”这个引用了，编译器会检查代码，如果你试图将变量再次初始化的话，编译器会报编译错误。二、修饰数据在编写程序时，我们经常需要说明一个数据是不可变的，我们成为常量。在java中，用final关键字修饰的变量，只能进行一次赋值操作，并且在生存期内不可以改变它的值。更重要的是，final会告诉编译器，这个数据是不会修改的，那么编译器就可能会在编译时期就对该数据进行替换甚至执行计算，这样可以对我们的程序起到一点优化。不过在针对基本类型和引用类型时，final关键字的效果存在细微差别。我们来看下面的例子： class Value { int v; public Value(int v) { this.v = v; } } public class finaltest { final int f1 = 1; final int f2; public finaltest() { f2 = 2; } public static void main(String[] args) { final int value1 = 1; // value1 = 4; System.out.println(value1); final double value2; value2