int nextToken()
描述 (Description)
java.io.StreamTokenizer.nextToken()方法解析此tokenizer的输入流中的下一个标记。 在ttype字段中返回下一个标记的类型。 有关令牌的其他信息可能位于此标记生成器的nval字段或sval字段中。 此类的典型客户端首先设置语法表,然后在循环中调用nextToken来解析连续的令牌,直到返回TT_EOF。
声明 (Declaration)
以下是java.io.StreamTokenizer.nextToken()方法的声明。
public int nextToken()
参数 (Parameters)
NA
返回值 (Return Value)
此方法返回ttype字段的值。
异常 (Exception)
IOException - 如果发生I/O错误。
例子 (Example)
以下示例显示了java.io.StreamTokenizer.nextToken()方法的用法。
package com.iowiki;
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);
// 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: Hello.
Word: This
Word: is
Word: a
Word: text
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.