Java.io.StreamTokenizer.slashSlashComments() 方法

  • 描述

    java.io.StreamTokenizer.slashSlashComments(boolean flag) 方法确定标记生成器是否识别C++ -风格的注释。如果 flag 参数为 true,则此流标记器识别 C++ 样式的注释。任何出现的两个连续斜杠字符 ('/') 都被视为注释的开始,该注释一直延伸到行尾。如果 flag 参数为 false,则不会对 C++ 样式的注释进行特殊处理。
  • 声明

    以下是java.io.StreamTokenizer.slashSlashComments()方法的声明。
     public void slashSlashComments(boolean flag)
  • 参数

    flag - true 表示识别和忽略 C++ 风格的注释。
  • 返回值

    此方法不返回值。
  • 异常

    N/A
  • 例子

    以下示例显示java.io.StreamTokenizer.slashSlashComments()方法的用法。
     
    package com.jc2182;
    
    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 slash-slash comments as recognizable
             st.slashSlashComments(true);
    
             // 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();
          }
       }
    }
    
    让我们编译并运行以上程序,这将产生以下结果-
     
    Word: CHello.
    Word: This
    Word: is
    Word: a
    Word: text
    Word: that
    End of File encountered.