Java 逐行读写 TXT 文件
package com.weixiao.download;
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileReader;
import java.io.FileWriter;
import java.util.HashMap;
import java.util.Map;
import org.apache.log4j.Logger;
public class IOHelper {
private static Logger logger = Logger.getLogger(IOHelper.class);
/**
* 获取 BufferedReader 实例
* @author lipw
* @date 2017年12月14日上午9:50:37
* @param filePath 文件路径
* @return
*/
public static BufferedReader getBufferedReader(String filePath) {
File file = new File(filePath);
BufferedReader reader = null;
try {
reader = new BufferedReader(new FileReader(file));
} catch (Exception e) {
e.printStackTrace();
} finally {
// todo
}
return reader;
}
/**
* 获取 BufferedWriter 实例
* @author lipw
* @date 2017年12月14日上午9:50:07
* @param filePath 文件路径
* @return
*/
public static BufferedWriter getBufferedWriter(String filePath) {
File file = new File(filePath);
BufferedWriter writer = null;
try {
writer = new BufferedWriter(new FileWriter(file));
} catch (Exception e) {
e.printStackTrace();
} finally {
// todo
}
return writer;
}
/**
* 处理博客排序
* @author lipw
* @date 2017年12月14日上午9:47:06
* @param filePath 混序文件路径
* @param outPath 按顺序排列的输出文件路径
*/
public static void handBlogOrder(String filePath, String outPath) {
BufferedReader reader = getBufferedReader(filePath);
BufferedWriter writer = getBufferedWriter(outPath);
// 用户按排名记录
Map<Integer, String> blogMap = new HashMap<Integer, String>();
if (reader == null) {
logger.warn("读取文件失败！");
return;
}
if (writer == null) {
logger.warn("写入文件失败！");
return;
}
String lineStr = null;
int line = 1;
try {
// 逐行读取并处理
while ((lineStr = reader.readLine()) != null) {
// 6,===http://blog.csdn.net/augusdi
lineStr = lineStr.replaceAll("\\[com.weixiao.download.CsdnBlogDownloader\\]\\-排名：", "");
String[] blog = lineStr.split(",===");
if (blog.length != 2) {
continue;
}
if (blog[0].length() > 3) {
continue;
}
Integer num = Integer.parseInt(blog[0]);
if (num > 200) {
continue;
}
System.out.println("line" + line + ":" + lineStr);
line++;
// 放到 Map 缓存中
blogMap.put(num, lineStr);
}
// 根据排名索引读取并写入文件
for (int i = 0; i < 201; i++) {
lineStr = blogMap.get(i);
if (lineStr != null) {
writer.write(lineStr + "\r\n");
}
}
} catch (Exception e) {
e.printStackTrace();
} finally {
// 用完了记得关闭
if (reader != null) {
try {
reader.close();
} catch (Exception e) {
e.printStackTrace();
}
}
// 用完了记得关闭
if (writer != null) {
try {
writer.close();
} catch (Exception e) {
e.printStackTrace();
}
}
}
}
public static void main(String[] args) {
//处理博客排序
handBlogOrder("/Users/aven/Downloads/blogOrder.txt", "/Users/aven/Downloads/blogOrder200.txt");
}
}输入文件内容示例：
[com.weixiao.download.CsdnBlogDownloader]-排名：496,===http://blog.csdn.net/raptor [com.weixiao.download.CsdnBlogDownloader]-排名：515,===http://blog.csdn.net/zdy0_2004 [com.weixiao.download.CsdnBlogDownloader]-排名：374,===http://blog.csdn.net/hejianhua [com.weixiao.download.CsdnBlogDownloader]-排名：311,===http://blog.csdn.net/q383965374 [com.weixiao.download.CsdnBlogDownloader]-排名：868,===http://blog.csdn.net/kongqz [com.weixiao.download.CsdnBlogDownloader]-排名：675,===http://blog.csdn.net/lufy_Legend [com.weixiao.download.CsdnBlogDownloader]-排名：88,===http://blog.csdn.net/byxdaz [com.weixiao.download.CsdnBlogDownloader]-排名：250,===http://blog.csdn.net/yenange [com.weixiao.download.CsdnBlogDownloader]-排名：423,===http://blog.csdn.net/kkdelta [com.weixiao.download.CsdnBlogDownloader]-排名：208,===http://blog.csdn.net/matrix67 [com.weixiao.download.CsdnBlogDownloader]-排名：10,===http://blog.csdn.net/dyllove98 [com.weixiao.download.CsdnBlogDownloader]-排名：642,===http://blog.csdn.net/redarmy_chen [com.weixiao.download.CsdnBlogDownloader]-排名：957,===http://blog.csdn.net/chenleixing
输出文件内容示例：
1,===http://blog.csdn.net/abc649395594 2,===http://blog.csdn.net/phphot 3,===http://blog.csdn.net/ooduil 4,===http://blog.csdn.net/yuanmeng001 5,===http://blog.csdn.net/tianlesoftware 6,===http://blog.csdn.net/augusdi 7,===http://blog.csdn.net/chimomo 10,===http://blog.csdn.net/dyllove98相关文章：
