Java.io.StreamTokenizer.quoteChar() 方法

描述

java.io.StreamTokenizer.quoteChar(int ch) 方法规定，在此标记生成该字符界定字符串常量的匹配对。当 nextToken 方法遇到字符串常量时，ttype 字段设置为字符串分隔符，sval 字段设置为字符串的主体。如果遇到字符串引号字符，则识别字符串，由字符串引号字符之后（但不包括）到（但不包括）下一次出现的相同字符串引号字符或行终止符组成, 或文件结尾。在解析字符串时，通常的转义序列（例如“\n”和“\t”）会被识别并转换为单个字符。指定字符的任何其他属性设置都将被清除。

声明

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

 public void quoteChar(int ch)

参数

ch - 字符。

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.quoteChar()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);

         // specify o as a quote char
         st.quoteChar('o');

         // 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: AHell
o encountered.
Word: that
Word: will
Word: be
Word: split
Word: int
o encountered.
Word: kens.
Number: 1.0
+ encountered.
Number: 1.0
= encountered.
Number: 2.0
End of File encountered.