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判断文件是否存在,存在则读取,不存在则生成文件

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如题,判断本地文件是否存在,是则读取文件内容,否则创建该文件,代码丑陋,见谅。

package com.agehua.utils;

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.FileReader;
import java.io.IOException;
import java.io.OutputStreamWriter;
import java.io.Writer;

/**
 * @author Agehua
 *
 */
public class FirstUse {

	public FirstUse(){

	}
	
	public void FirstOrNot(){
		java.io.File firstUsed = new File("use");
		try {
			if (firstUsed.exists()){
				//读取文件内容
				BufferedReader in = new BufferedReader(new FileReader(firstUsed));
				String firstOrNot;
				try {
					while ((firstOrNot = in.readLine())!= null){
						System.out.println(firstOrNot);
					}
					in.close();
				} catch (IOException e) {
					// TODO Auto-generated catch block
					System.out.println("文件写入失败!!!");
					e.printStackTrace();
				}
			}else {
				try {
				//文件不存在就生成该文件
				Writer out = new BufferedWriter(new OutputStreamWriter(new FileOutputStream("use"),"GB2312"));
				String s = "First = false";
				out.write(s);
				out.close();
				}catch (IOException e) {
					// TODO: handle exception
					System.out.println("文件内容读取失败!!!");
					e.printStackTrace();
				}
			}
		} catch (FileNotFoundException e) {
			// TODO Auto-generated catch block
			System.out.println("验证文件不存在!!!");
			e.printStackTrace();
		}
	}
	
	public static void main(String[] args){
		FirstUse fu = new FirstUse();
		fu.FirstOrNot();
	}
}

 

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