java 倒序读取文件（最后一行开始读取）

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Java代码

package cn.com.songjy.test.io;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.RandomAccessFile;
/**
* http://bbs.csdn.net/topics/190181198
* 从最后一行开始读取
*/
public class FromEndRF {
/**
*
* @param filename 目标文件
* @param charset 目标文件的编码格式
*/
public static void read(String filename, String charset) {
RandomAccessFile rf = null;
try {
rf = new RandomAccessFile(filename, "r");
long len = rf.length();
long start = rf.getFilePointer();
long nextend = start + len - 1;
String line;
rf.seek(nextend);
int c = -1;
while (nextend > start) {
c = rf.read();
if (c == '\n' || c =='\r') {
line = rf.readLine();
if (line != null) {
System.out.println(new String(line
.getBytes("ISO-8859-1"), charset));
} else {
System.out.println(line);
}
nextend--;
}
nextend--;
rf.seek(nextend);
if (nextend == 0) {// 当文件指针退至文件开始处，输出第一行
// System.out.println(rf.readLine());
System.out.println(new String(rf.readLine().getBytes(
"ISO-8859-1"), charset));
}
}
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} finally {
try {
if (rf != null)
rf.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
public static void main(String args[]) {
read("mynewfile.txt", "UTF-8");
}
}

package cn.com.songjy.test.io;import java.io.FileNotFoundException;import java.io.IOException;import java.io.RandomAccessFile;/** * http://bbs.csdn.net/topics/190181198 * 从最后一行开始读取 */public class FromEndRF {/** *  * @param filename 目标文件 * @param charset 目标文件的编码格式 */public static void read(String filename, String charset) {RandomAccessFile rf = null;try {rf = new RandomAccessFile(filename, "r");long len = rf.length();long start = rf.getFilePointer();long nextend = start + len - 1;String line;rf.seek(nextend);int c = -1;while (nextend > start) {c = rf.read();if (c == '\n' || c == '\r') {line = rf.readLine();if (line != null) {System.out.println(new String(line.getBytes("ISO-8859-1"), charset));} else {System.out.println(line);}nextend--;}nextend--;rf.seek(nextend);if (nextend == 0) {// 当文件指针退至文件开始处，输出第一行// System.out.println(rf.readLine());System.out.println(new String(rf.readLine().getBytes("ISO-8859-1"), charset));}}} catch (FileNotFoundException e) {e.printStackTrace();} catch (IOException e) {e.printStackTrace();} finally {try {if (rf != null)rf.close();} catch (IOException e) {e.printStackTrace();}}}public static void main(String args[]) {read("mynewfile.txt", "UTF-8");}}