Android 多个文件写入一个文件，读取文件中的内容，追加写入；正常写file

package com.example.lib_tab;
 
import com.alibaba.fastjson.JSONArray;
import com.alibaba.fastjson.JSONObject;
 
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStreamReader;
 
public class MyClass {
 
    private static String targetFilePath = "C:\\Users\\HASEE\\Desktop\\Downloads\\clean3";
    private static String copyFilePath = "C:\\Users\\HASEE\\Desktop\\Downloads\\total.json";
 
    public static void main(String[] args) {
 
 
        //定义输出目录
//        String copyFilePath="E:\\Mycode\\SBgong\\output\\1.txt";
        int fileCount = 0;
        int folderConut = 0;
 
 
        try {
            BufferedWriter bw = new BufferedWriter(new FileWriter(copyFilePath));
            File[] list = new File(targetFilePath).listFiles();
            for (File file : list) {
                if (file.isFile()) {
                    fileCount++;
                    file.getAbsolutePath();
                    BufferedReader br = new BufferedReader(new InputStreamReader(new FileInputStream(file), "utf-8"));
                    String line;
                    while ((line = br.readLine()) != null) {
                        bw.write(line + ",");
                        bw.newLine();
                    }
                    br.close();
                } else {
                    folderConut++;
                }
            }
            bw.close();
            String content = readFileContent(copyFilePath);
            content="["+content.substring(0,content.length()-1)+"]";
            JSONArray jsonArray = JSONObject.parseArray(content);
//            system  cache  apk  residual
            Object o = jsonArray.getJSONObject(0);
            for (int i=0;i<jsonArray.size();i++){
                JSONObject jsonObject=jsonArray.getJSONObject(i);
                JSONArray systemArray = jsonObject.getJSONArray("system");
                JSONArray cacheArray = jsonObject.getJSONArray("cache");
                JSONArray apkArray = jsonObject.getJSONArray("apk");
                JSONArray residualArray = jsonObject.getJSONArray("residual");
            }
//            jsonObject.getString("");
            System.out.println("jsonArray.size:"+jsonArray.size());
        } catch (Exception e) {
 
        }
 
    }
 
    /**
     * 获取文件中文本内容
     * @param fileName 文件路劲名
     * @return
     */
    public static String readFileContent(String fileName) {
        File file = new File(fileName);
        BufferedReader reader = null;
        StringBuffer sbf = new StringBuffer();
        try {
            reader = new BufferedReader(new FileReader(file));
            String tempStr;
            while ((tempStr = reader.readLine()) != null) {
                sbf.append(tempStr);
            }
            reader.close();
            return sbf.toString();
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            if (reader != null) {
                try {
                    reader.close();
                } catch (IOException e1) {
                    e1.printStackTrace();
                }
            }
        }
        return sbf.toString();
    }
}
 
/**
*
*追加写入
*/
    public void method1() {
        FileWriter fw = null;
        try {
//如果文件存在，则追加内容；如果文件不存在，则创建文件
            File f=new File("E:\\dd.txt");
            fw = new FileWriter(f, true);
            PrintWriter pw = new PrintWriter(fw);
            pw.println("追加内容");
            pw.flush();
            fw.flush();
            pw.close();
            fw.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
 
    }

******正常写：

    private static final String save_path="C:\\Users\\HASEE\\Desktop\\广告sdk\\log.txt";
    
    /**
     * @param content 保存字符串
     */
    public static void saveContent(String content){
        try {
            File f = new File(save_path);
            FileWriter fw = new FileWriter(f, true);
            PrintWriter pw = new PrintWriter(fw);
            pw.println(content);
            pw.flush();
            fw.flush();
            pw.close();
            fw.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }