Java.io.StreamTokenizer.ordinaryChar() 方法

描述

java.io.StreamTokenizer.ordinaryChar(int ch) 方法指定字符参数在此标记器中是"ordinary"。 它删除了字符作为注释字符、单词组件、字符串分隔符、空格或数字字符的任何特殊意义。 当解析器遇到这样的字符时，解析器将其视为单字符标记并将 ttype 字段设置为字符值。

将行终止符设置为"ordinary"可能会干扰 StreamTokenizer 计算行数的能力。 lineno 方法可能不再在其行数中反映此类终止符的存在。

声明

以下是 java.io.StreamTokenizer.ordinaryChar() 方法的声明。

public void ordinaryChar(int ch)

参数

ch − 字符

返回值

此方法不返回值。

异常

NA

示例

下面的例子展示了 java.io.StreamTokenizer.ordinaryChar() 方法的使用。

package com.tutorialspoint;

import java.io.*;

public class StreamTokenizerDemo {
   public static void main(String[] args) {
      String text = "Hello. This is a text \n that will be split "
         + "into tokens. 1 + 1 = 2";
         
      try {
         // create a new file with an ObjectOutputStream
         FileOutputStream out = new FileOutputStream("test.txt");
         ObjectOutputStream oout = new ObjectOutputStream(out);

         // write something in the file
         oout.writeUTF(text);
         oout.flush();

         // create an ObjectInputStream for the file we created before
         ObjectInputStream ois = new ObjectInputStream(new FileInputStream("test.txt"));

         // create a new tokenizer
         Reader r = new BufferedReader(new InputStreamReader(ois));
         StreamTokenizer st = new StreamTokenizer(r);

         // set \n as an ordinary char
         st.ordinaryChar('\n');

         // print the stream tokens
         boolean eof = false;
         
         do {
            int token = st.nextToken();
            
            switch (token) {
               case StreamTokenizer.TT_EOF:
                  System.out.println("End of File encountered.");
                  eof = true;
                  break; 
                  
               case StreamTokenizer.TT_EOL:
                  System.out.println("End of Line encountered.");
                  break;
                  
               case StreamTokenizer.TT_WORD:
                  System.out.println("Word: " + st.sval);
                  break;
                  
               case StreamTokenizer.TT_NUMBER:
                  System.out.println("Number: " + st.nval);
                  break;
                  
               default:
                  System.out.println((char) token + " encountered.");
                  
                  if (token == '!') {
                     eof = true;
                  }
            }
         } while (!eof);

      } catch (Exception ex) {
         ex.printStackTrace();
      }
   }
}

让我们编译并运行上面的程序，这将产生下面的结果 −

Word: AHello.
Word: This
Word: is
Word: a
Word: text
End of Line encountered.
Word: that
Word: will
Word: be
Word: split
Word: into
Word: tokens.
Number: 1.0
+ encountered.
Number: 1.0
= encountered.
Number: 2.0
End of File encountered.