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Java尾部递归:在Fibonacci代码下面是否尾部递归?

[英]Java tail recursion : Is below Fibonacci code tail recursive ?

I recently learnt about tail recursion. 我最近了解了尾递归。 I understand, many programming language compilers perform[Current java doesn't] s, code optimization when it finds a recursive method a "Tail recursive". 我了解,许多编程语言编译器在找到递归方法“尾递归”时会执行代码优化。

My understanding of TR : Compiler, does not create new stack frame(instead replace with older call's stack frame) when there is no further operation to be performed after the call has returned. 我对TR的理解:编译器在调用返回后不再执行任何操作时不会创建新的堆栈框架(而是替换为较早的调用的堆栈框架)。

Is below code[ even though in java] a tail recursive ? 下面的代码[即使在Java中]是尾递归的吗?

suppose totalSeriesLenght = 10. 假设totalSeriesLenght = 10。

public void generateFibonacciSeries(int totalSeriesLenght) {
    int firstNum = 0;
    int secondNum = 1;
    printNextFibonacciNumber(firstNum, secondNum,totalSeriesLenght);
}

public void  printNextFibonacciNumber(int fiboOne , int fiboTwo,int totalSeriesLenght) {
    if(totalSeriesLenght >= 1) {
        System.out.print(fiboOne + ",");
        int fiboNext = fiboOne + fiboTwo;           
        totalSeriesLenght --;
        printNextFibonacciNumber(fiboTwo, fiboNext,totalSeriesLenght);
    }
}

Yes the function call is tail-recursive, but Java does not have any tail call optimization, so new stack frames will be created. 是的,函数调用是尾部递归的,但是Java没有任何尾部调用优化,因此将创建新的堆栈框架。

As proof consider the following program: 作为证明,请考虑以下程序:

public class Test{
  public static void main(String[] args){
    recursive();
  }

  public static void recursive(){
    recursive();
  }
}

running this program results in a StackOverflowError which means that the stack had to be filled with something: stack frames! 运行该程序会导致StackOverflowError,这意味着堆栈中必须填充某些东西:堆栈框架!

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