blocks|key|958714|text|当你使用new+AClass+{+...+}时，你正在创建一个扩展这个类的匿名类。当一个类是final时，它不能被扩展。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|958715|一种做你想做的事情的方法是这样的：|958716|val+a:+AClass+=+new+AClass+
import+a._
setStr("Pooya")
func1(this)|code-block|syntax|javascript|958717|遵循@Vladimir的建议，以一种稍微干净的方式：|958718|val+a:+AClass+=+{+val+a+=+new+AClass+
++import+a._
++setStr("Pooya")
++func1(this)+
++a+
}|958719|现在，您可以多次重复该操作，而不会使setStr模棱两可。对于具有当前定义的func1来说，它是否在{}块中应该无关紧要。|958720|entityMap^0|4|I|1A|5|0|0|0|0|0|I|6|12|5|1E|2|0^^$0|@$1|2|3|4|5|6|7|U|8|@$9|V|A|W|B|C]|$9|X|A|Y|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|Z|8|@]|D|@]|E|$]]|$1|H|3|I|5|J|7|10|8|@]|D|@]|E|$K|L]]|$1|M|3|N|5|6|7|11|8|@]|D|@]|E|$]]|$1|O|3|P|5|J|7|12|8|@]|D|@]|E|$K|L]]|$1|Q|3|R|5|6|7|13|8|@$9|14|A|15|B|C]|$9|16|A|17|B|C]|$9|18|A|19|B|C]]|D|@]|E|$]]|$1|S|3|-4|5|6|7|1A|8|@]|D|@]|E|$]]]|T|$]]

When you do <code>new AClass { ... }</code> you are creating an anonymous class that extends this class. When a class is <code>final</code> it cannot be extended.

One way to do what you want is like that:

<pre><code>val a: AClass = new AClass 
import a._
setStr("Pooya")
func1(this)
</code></pre>

Following @Vladimir's suggestion, a slightly cleaner way:

<pre><code>val a: AClass = { val a = new AClass 
 import a._
 setStr("Pooya")
 func1(this) 
 a 
}
</code></pre>

Now you can repeat that as many times as you want without making <code>setStr</code> ambiguous. For the <code>func1</code>, with its current definition, should't matter if it's in the <code>{}</code> block or not.

blocks|key|2555213|text|要获得final语义，请将初始状态传递给构造函数。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|2555214|另一种模式是使用早期定义。请注意，BClass#strs是最终版本。|2555215|最后的意思是当你的初始化器完成时，值不能改变。|2555216|并失去可变状态。|2555217|但是，如果您喜欢或需要可变性，那么在构建对象时，可以使用伴生对象上的工厂来处理您需要的任何正常工作。|2555218|package+inheritthewind

object+Test+extends+App+{
++val+a+=+new+AClass(new+AInit+{+val+str+=+"Pooya"+})
++a.aMethod()
++val+b+=+new+{
++++val+str:+String+=+"Pooya"
++}+with+BClass
++b.aMethod()
++val+b2+=+new+BClass+{
++++val+str:+String+=+"Pooya"
++}
++b2.aMethod()++//+uh+no,+result+is+"nulls"
++val+c+=+CClass(new+CPrototype+{+val+str+=+"Pooya"+})
++c.aMethod()
++//+not+allowed
++//val+nope+=+new+CClass
}

trait+AInit+{
++def+str:+String
}

final+class+AClass(init:+AInit)+{
++private+final+val+str:+String+=+init.str
++def+aMethod()+=+Console+println+str
}

abstract+class+BClass+{
++val+str:+String
++final+val+strs+=+str+%2B+"s"
++def+aMethod()+=+Console+println+strs
}

trait+CPrototype+extends+AInit

final+class+CClass+private()+{
++private+var+str:+String+=+_
++def+aMethod()+=+Console+println+str
}
object+CClass+{
++def+apply(p:+CPrototype):+CClass+=+{
++++val+res+=+new+CClass
++++res.str+=+p.str
++++res
++}
}|code-block|syntax|javascript|2555219|和|2555220|scala>+:javap+-pv+inheritthewind.BClass
[snip]
++private+final+java.lang.String+strs;
++++flags:+ACC_PRIVATE,+ACC_FINAL

++public+abstract+java.lang.String+str();
++++flags:+ACC_PUBLIC,+ACC_ABSTRACT

++public+final+java.lang.String+strs();
++++flags:+ACC_PUBLIC,+ACC_FINAL|2555221|entityMap^0|3|5|0|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|Y|8|@$9|Z|A|10|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|11|8|@]|D|@]|E|$]]|$1|H|3|I|5|6|7|12|8|@]|D|@]|E|$]]|$1|J|3|K|5|6|7|13|8|@]|D|@]|E|$]]|$1|L|3|M|5|6|7|14|8|@]|D|@]|E|$]]|$1|N|3|O|5|P|7|15|8|@]|D|@]|E|$Q|R]]|$1|S|3|T|5|6|7|16|8|@]|D|@]|E|$]]|$1|U|3|V|5|P|7|17|8|@]|D|@]|E|$Q|R]]|$1|W|3|-4|5|6|7|18|8|@]|D|@]|E|$]]]|X|$]]

To get <code>final</code> semantics, pass in your initial state to the constructor.

The other mode is to use early definitions. Note that BClass#strs is final.

Final means that when your initializer is done, the value mustn't change.

And lose the mutable state.

But if you love or need mutability, a factory on the companion object can work whatever sanity you require when you build the object.

<pre><code>package inheritthewind

object Test extends App {
 val a = new AClass(new AInit { val str = "Pooya" })
 a.aMethod()
 val b = new {
 val str: String = "Pooya"
 } with BClass
 b.aMethod()
 val b2 = new BClass {
 val str: String = "Pooya"
 }
 b2.aMethod() // uh no, result is "nulls"
 val c = CClass(new CPrototype { val str = "Pooya" })
 c.aMethod()
 // not allowed
 //val nope = new CClass
}

trait AInit {
 def str: String
}

final class AClass(init: AInit) {
 private final val str: String = init.str
 def aMethod() = Console println str
}

abstract class BClass {
 val str: String
 final val strs = str + "s"
 def aMethod() = Console println strs
}

trait CPrototype extends AInit

final class CClass private() {
 private var str: String = _
 def aMethod() = Console println str
}
object CClass {
 def apply(p: CPrototype): CClass = {
 val res = new CClass
 res.str = p.str
 res
 }
}
</code></pre>

And

<pre><code>scala&gt; :javap -pv inheritthewind.BClass
[snip]
 private final java.lang.String strs;
 flags: ACC_PRIVATE, ACC_FINAL

 public abstract java.lang.String str();
 flags: ACC_PUBLIC, ACC_ABSTRACT

 public final java.lang.String strs();
 flags: ACC_PUBLIC, ACC_FINAL
</code></pre>

I have this code in Scala
when I define the <code>a</code> value, Also I call some methods in the object like <code>setStr</code> and it is very useful and amazing. But when I define my <code>AClass</code> as final, compiler will throws an exception as Illegal inheritance from final class. In some cases I should use final classes and this type of method calling after the class initiation is very useful to me, and my question is how to solve this problem 

<pre><code>test("Test function call") {
 val a: AClass = new AClass {
 setStr("Pooya")
 func1(this)
 }
}

class AClass { // when I declare the class final, the compiler will raise an error
 private var str:String=""
 def setStr(str:String)={
 this.str=str
 }
 def aMethod() = print(str)
}

def func1(a: AClass) {
 a.aMethod()
}
</code></pre>

How to solve Illegal inheritance from final class in Scala

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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当我定义a值时，我用Scala编写了这段代码，我还调用了对象中的一些方法，比如setStr，它非常有用，令人惊叹。但是当我将我的AClass定义为final时，编译器会抛出一个异常，因为非法继承了final类。在某些情况下，我应该使用final类，在类初始化之后调用这种类型的方法对我来说非常有用，我的问题是如何解决这个...

问如何解决Scala中从最终类非法继承的问题
EN

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