Java StreamTokenizer eolIsSignificant()方法及示例
StreamTokenizer类eolIsSignificant()
方法
eolIsSignificant()方法在java.io包中可用。
eolIsSignificant()方法用于识别行尾是否被视为标记。当布尔变量设置为true时,如果指示将行的末尾视为标记,并nextToken()
返回TT_EOL并在布尔值设置为false时读取行的末尾,则将type字段设置为该值,则表示结束该行的空格被视为空白,并且仅分配给单独的令牌。
eolIsSignificant()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。
在检查行尾是否有意义时,eolIsSignificant()方法不会引发异常。
语法:
Public void eolIsSignificant(boolean status);
参数:
布尔状态–当它标识行尾字符是单独的标记时,此参数设置为true;否则,它标识行尾字符是空格。
返回值:
该方法的返回类型为void,不返回任何内容。
示例
//Java程序演示示例 //eolIsSignificant(booleanstatus)方法的 //StreamTokenizer- import java.io.*; public class EolIsSignificant { public static void main(String[] args) { String str = "Hi, This is a mathematical expression : \n" + " 2 * 4 = 8" + "8 + 5 = 13"; try { //实例化FileOutputStream和ObjectOutputStream- FileOutputStream fos_stm = new FileOutputStream("D:\\includehelp.txt"); ObjectOutputStream obj_out_stm = new ObjectOutputStream(fos_stm); //通过使用writeUTF()方法是 //将给定的字符串写入文件 obj_out_stm.writeUTF(str); obj_out_stm.flush(); //实例化FileOutputStream和ObjectOutputStream- ObjectInputStream obj_in_stm = new ObjectInputStream(new FileInputStream("D:\\includehelp.txt")); //实例化StreamTokenizer和Reader- Reader reader = new BufferedReader(new InputStreamReader(obj_in_stm)); StreamTokenizer st = new StreamTokenizer(reader); //通过使用eolIsSignificant()方法是 //将行尾设置为空白 //即“\n”被视为空格,而不是"\n"considers as whitespace instead of //找到行尾 st.eolIsSignificant(false); //在这里,我们开始考虑 //文件不为空 boolean end_of_file = false; while (!end_of_file) { 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
= Found. word: Hi , Found. word: This word: is word: a word: mathematical word: expression : Found. number: 2.0 * Found. number: 4.0 = Found. number: 88.0 + Found. number: 5.0 = Found. number: 13.0 End of File Found