java - 如何查询报关单？

Question

我正在解决一个问题，我有一个字符串列表，它只不过是一个java代码。因此，如果该代码在方法体之前或之后有任何声明，那么该脚本应该给我一个错误。如果变量声明位于方法体内，那么它应该可以正常工作。
例如:

int abcs; // This should generate error.
double cad;  //This should generate error.

Void main(){
  int test;   //This should not generate error.

  void test1(){
    int test3;   //This should not generate error.
   }
}

我为此编写了一个小程序，但无法获得所需的结果，我的代码是:

private void check( String line)

{ 整数计数 = 0; int 标志 = 0;

    // is there an open brace on the current line
    int bracketpos = line.indexOf('{');
    // is there a close brace on the current line
    int closebracketpos = line.indexOf('}');
    // is there a semicolon on the current line
    int charpos = line.indexOf(';');

    // increment count if there is an open brace
    if(bracketpos>=0 )
        ++count;

    // decrement count if there is a close brace
    if(closebracketpos>=0 )
        --count;

    // if there is an open brace on the current line
    // ...and there's a close brace on the current line
    // ...and there's a semicolon on the current line
    // ...and the number of brackets are balanced (count==0)
    if(bracketpos>=0 && closebracketpos>=0 && charpos>=0 && count==0){
        // if the first semicolon appears after the first close brace
        if(charpos>closebracketpos){
            flag =2;
        }
        else
            // the close brace appears after the semicolon, or neither exist
            flag =0;
    }

    else if (charpos >= 0 && count ==0) {

        flag= 1;
    } 
    else {
    flag = 0;
        // the line does not have a ;,{,}
    }

if(flag!=0)
 {
       //ERROR
 }
}

我正在逐行传递示例，因此 count 正在记录“{”和“}”。

问题:我将示例逐行输入到 check() 中。我想检查一下示例中是否有任何声明。但是如果方法体内有任何声明那就没问题，但是如果方法体外有声明那么我的 check() 应该提示/或者给我一个错误。

Answer 1

你的逻辑是错误的。您应该添加注释来描述代码在每个阶段的作用。这是让您开始的...

private void check( String line)
{       int count = 0;
        int flag = 0;

        // is there an open brace on the current line
        int bracketpos = line.indexOf('{');
        // is there a close brace on the current line
        int closebracketpos = line.indexOf('}');
        // is there a semicolon on the current line
        int charpos = line.indexOf(';');

        // increment count if there is an open brace
        if(bracketpos>=0 )
            ++count;

        // decrement count if there is a close brace
        if(closebracketpos>=0 )
            --count;

        // if there is an open brace on the current line
        // ...and there's a close brace on the current line
        // ...and there's a semicolon on the current line
        // ...and the number of brackets are balanced (count==0)
        if(bracketpos>=0 && closebracketpos>=0 && charpos>=0 && count==0){
            // if the first semicolon appears after the first close brace
            if(charpos>closebracketpos){
                flag =2;
            }
            else
                // the close brace appears after the semicolon, or neither exist
                flag =0;
        }

        else if (charpos >= 0 && count ==0) {

            flag= 1;
        } 
        else {
        flag = 0;
            // the line does not have a ;,{,}
        }

  if(flag!=0)
{
        //ERROR
    }
}