// DeleteLastLine.java import java.io.*;public class DeleteLastLine { public static void main(String [] args) throws IOException { RandomAccessFile raf = new RandomAccessFile("DeleteLastLine.java", "rw"); long len = raf.length(); raf.setLength(len - 2); raf.close(); } }------------------------------------------------------------------------------
RandomAccessFile raf = new RandomAccessFile("c:/data.text", "rw"); long len = raf.length(); long lastLineLength = ? raf.setLength(len - lastLineLength);用raf.seek(len)方法定位current offset in this file从后往前找'\n'就能得到最后一行的长度
从后往前seek()
从后往前seek(),seek 到了,怎么delete那行\n?
用哪个方法是删除一行或一个字符的?
import java.io.*;public class DeleteLastLine
{
public static void main(String [] args) throws IOException
{
RandomAccessFile raf = new RandomAccessFile("DeleteLastLine.java", "rw");
long len = raf.length();
raf.setLength(len - 2);
raf.close();
}
}------------------------------------------------------------------------------
long len = raf.length();
long lastLineLength = ?
raf.setLength(len - lastLineLength);用raf.seek(len)方法定位current offset in this file从后往前找'\n'就能得到最后一行的长度