Question

我不知道如何编写“下一个源字符”代码来查找字符串的下一个字符。

public class scanner {
    protected char currentChar;
    protected StringBuffer currentSpelling;
    protected byte currentKind;

    private void take (char expectedChar){
        if (currentChar == expectedChar){
            currentSpelling.append(currentChar);
            currentChar = next source character;
        }
    }


    private void takeIt(){
        currentSpelling.append(currentChar);
        currentChar = next source character;
    }

}

Answer 1

可能你需要定义你的字符来源。在这里，我将它传递给Scanner的构造函数。

public class Scanner {
    protected char currentChar;
    protected StringBuffer currentSpelling;
    protected byte currentKind;
    private Reader inputStreamReader;

    public Scanner(InputStream inputStream) {
        reader = new InputStreamReader(inputStream);
    }

    private void take (char expectedChar){
        if (currentChar == expectedChar){
            currentSpelling.append(currentChar);
            currentChar = (char) inputStreamReader.read();
        }
    }


    // Note. Probably you need to get the currentChar before append it.
    // So the order of operations should be inverted
    private void takeIt(){
        currentSpelling.append(currentChar);
        currentChar = (char) inputStreamReader.read();
    }

}

要创建它，您可以执行类似的操作（或者您可以将其替换为从另一个流中读取数据，例如文件）：

Scanner myScanner = new Scanner(System.in);

注意：我将类的名称从scanner更改为Scanner，因为将类设为大写是一种很好的做法。

如何在Java中使用解析器的扫描程序中的下一个字符

1 个答案: