📅 最后修改于: 2020-09-27 07:22:24 🧑 作者: Mango
Java PushbackReader类是字符流读取器。它用于将字符推回流中并覆盖FilterReader类。
我们来看一下java.io.PushbackReader类的声明：
public class PushbackReader extends FilterReader
| Method | Description |
|---|---|
| int read() | It is used to read a single character. |
| void mark(int readAheadLimit) | It is used to mark the present position in a stream. |
| boolean ready() | It is used to tell whether the stream is ready to be read. |
| boolean markSupported() | It is used to tell whether the stream supports mark() operation. |
| long skip(long n) | It is used to skip the character. |
| void unread (int c) | It is used to pushes back the character by copying it to the pushback buffer. |
| void unread (char[] cbuf) | It is used to pushes back an array of character by copying it to the pushback buffer. |
| void reset() | It is used to reset the stream. |
| void close() | It is used to close the stream. |
import java.io.*;
public class ReaderExample{
public static void main(String[] args) throws Exception {
char ary[] = {'1','-','-','2','-','3','4','-','-','-','5','6'};
CharArrayReader reader = new CharArrayReader(ary);
PushbackReader push = new PushbackReader(reader);
int i;
while( (i = push.read())!= -1) {
if(i == '-') {
int j;
if( (j = push.read()) == '-'){
System.out.print("#*");
}else {
push.unread(j); // push back single character
System.out.print((char)i);
}
}else {
System.out.print((char)i);
}
}
}
}
输出量
1#*2-34#*-56