Java Java.io.StreamTokenizer.ordinaryChar()用法及代码示例

描述

这个java.io.StreamTokenizer.ordinaryChar(int ch)方法指定此分词器中的字符参数为 "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。

制作行终止符 "ordinary" 可能会干扰 StreamTokenizer 计算行数的能力。 lineno 方法可能不再反映其行数中此类终止符的存在。

声明

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

public void ordinaryChar(int ch)

参数

ch─ 角色。

返回值

此方法不返回值。

异常

NA

示例

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

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，这将产生以下结果——

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.