Java StreamTokenizer slashSlashComments()方法及示例
StreamTokenizer类slashSlashComments()方法
slashSlashComments()方法在java.io包中可用。
slashSlashComments()方法用于标识此StreamTokenizer是否识别双斜杠注释（C++类型注释）。当布尔变量设置为true时，表明此StreamTokenizer识别双斜杠注释，否则特别不使用双斜杠注释。
slashSlashComments()方法是一种非静态方法，只能通过类对象访问，如果尝试使用类名称访问该方法，则会收到错误消息。
slashSlashComments()方法在标识双斜杠注释时不会引发异常。
语法：
Public void slashSlashComments(boolean status);
参数：
布尔状态–当此参数识别并避免双斜杠注释（即，基于C++的注释）时，将其设置为true。
返回值：
该方法的返回类型为void，不返回任何内容。
示例
//“+”8+5=13“;“+”8+5=13“;“+”8+5=13“;Java程序演示示例
//“+”8+5=13“;“+”8+5=13“;“+”8+5=13“;无效的slashSlashComments（booleanstatus）
//“+”8+5=13“;“+”8+5=13“;“+”8+5=13“;StreamTokenizer的方法
import java.io.*;
public class slashSlashComments {
public static void main(String[] args) {
String str = "Hi, This is \n a mathematical expression :\n " +
" 2 * 4 = 8 //“+”8+5=13“;“+”8+5=13“;“+”8+5=13“;" + "8 + 5 = 13";
try {
//“+”8+5=13“;“+”8+5=13“;“+”8+5=13“; Instantiates FileOutputStream and ObjectOutputStream
FileOutputStream fos_stm = new FileOutputStream("D:\\includehelp.txt");
ObjectOutputStream obj_out_stm = new ObjectOutputStream(fos_stm);
//“+”8+5=13“;“+”8+5=13“;“+”8+5=13“; By using writeUTF() method is to
//“+”8+5=13“;“+”8+5=13“;“+”8+5=13“; write the given string in the file
obj_out_stm.writeUTF(str);
obj_out_stm.flush();
//“+”8+5=13“;“+”8+5=13“;“+”8+5=13“; Instantiates FileOutputStream and ObjectOutputStream
ObjectInputStream obj_in_stm = new ObjectInputStream(new FileInputStream("D:\\includehelp.txt"));
//“+”8+5=13“;“+”8+5=13“;“+”8+5=13“; Instantiates StreamTokenizer and Reader
Reader reader = new BufferedReader(new InputStreamReader(obj_in_stm));
StreamTokenizer st = new StreamTokenizer(reader);
//“+”8+5=13“;“+”8+5=13“;“+”8+5=13“; By using slashSlashComments() method is to
//“+”8+5=13“;“+”8+5=13“;“+”8+5=13“; set comments when boolean set to true and
//“+”8+5=13“;“+”8+5=13“;“+”8+5=13“; when it encounters '//“+”8+5=13“;“+”8+5=13“;“+”8+5=13“;' in str
st.slashSlashComments(true);
//“+”8+5=13“;“+”8+5=13“;“+”8+5=13“; Here, we are considering initially
//“+”8+5=13“;“+”8+5=13“;“+”8+5=13“; file is not empty
boolean end_of_file = false;
while (!end_of_file) {
//“+”8+5=13“;“+”8+5=13“;“+”8+5=13“; By using nextToken() method is to
//“+”8+5=13“;“+”8+5=13“;“+”8+5=13“; parse the next token from the stream
int token = st.nextToken();
switch (token) {
case StreamTokenizer.TT_EOF:
System.out.println("End of File Found");
end_of_file = true;
break;
case StreamTokenizer.TT_EOL:
System.out.println("End of Line Found");
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 + " Found.");
}
}
} catch (Exception ex) {
ex.printStackTrace();
}
}
}输出结果
word: BHi , Found. word: This word: is word: a word: mathematical word: expression : Found. number: 2.0 * Found. number: 4.0 = Found. number: 8.0 End of File Found