Question

当我第一次调用stream.next（）时，如何返回我输入的值？

> StringStream stream= new StringStream("pez");
> stream.next()
"pfa"
> stream.next()
"pfb"

例如，当我第一次调用stream.next（）时，它应该是“pez”，并且“pfa”应该出现，直到我第二次调用stream.next（）。

import java.io.*;

    //the class produces a continuous sequence of strings that consist of lower case letters.

    public class StringStream extends stream {
      //@param FirtsV is the first value we input
      private String FirstV;

      //the constructor that represents the first value returned by the stream.
      public StringStream(String FirstV) {
        this.FirstV = FirstV;
      }

      //the method returns the next value of the stream.
      public String next() {
        StringBuilder sb = new StringBuilder(FirstV);
        int l = sb.length();
        if(sb.charAt(l-1) < 'z') {
          sb.setCharAt(l-1, (char)(sb.charAt(l-1) + 1));
          FirstV = sb.toString();
        }else{
          if(sb.charAt(l-1) == 'z') {
            sb.setCharAt(l-1, 'a');
            sb.setCharAt(l-2, (char)(sb.charAt(l-2) + 1));
            FirstV = sb.toString();
        }
      }
       return FirstV;
      }

      @Override
      public String data() {
        return FirstV;
      }

    }

Answer 1

通过在开头添加以下行来修改next（）方法：

String originalV = FirstV;

然后将您的return语句更改为

return originalV;

如何首先返回原始值？

1 个答案: