java 从文件末尾开始读取文件内容

/**
* 从文件末尾开始读取文件，并逐行打印
* @param filename  file path
* @param charset character
*/
public static void readFileFromEnd(String filename, String charset) {
RandomAccessFile rf = null;
try {
rf = new RandomAccessFile(filename, "r");
long fileLength = rf.length();
long start = rf.getFilePointer();// 返回此文件中的当前偏移量
long readIndex = start + fileLength -1;
String line;
rf.seek(readIndex);// 设置偏移量为文件末尾
int c = -1;
while (readIndex > start) {
c = rf.read();
String readText = null;
if (c == '\n' || c == '\r') {
line = rf.readLine();
if (line != null) {
readText = new String(line.getBytes("ISO-8859-1"), charset);
} else {
System.out.println("read line : " + line);
}
readIndex--;
}
readIndex--;
rf.seek(readIndex);
if (readIndex == 0) {// 当文件指针退至文件开始处，输出第一行
readText = rf.readLine();
}
if (readText != null) {
System.out.println(readText);
}
}
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} finally {
try {
if (rf != null)
rf.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}