java读写文件

package com.v514.chapter;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.PrintWriter;

public class CountFileHandler {
public static void writeFile(String filename, long count) {
try {
PrintWriter out = new PrintWriter(new FileWriter(filename));//创建文件
out.println(count);//向文件中写数据
out.close();
} catch (IOException e) {
e.printStackTrace();
}
}

public static long readFile(String filename) {
File f = new File(filename);
long count = 0;
if (!f.exists()) {//文件不存在,创建文件,写入访问次数为0
writeFile(filename, 0);
}
try {
BufferedReader in = new BufferedReader(new FileReader(f));
count = Long.parseLong(in.readLine());
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (NumberFormatException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return count;
}
}


其中，在writeFile()这个方法中，参数filename是指定文件的路径。