最近的一些总结

我会带着你远行 2022-08-19 08:59 264阅读 0赞

**首先关于.zip文件的读取操作**

public static void test() { 
                long startTime=System.currentTimeMillis(); 
                try { 
                    ZipInputStream Zin=new ZipInputStream(new FileInputStream( 
                            "F:\\Parser.zip"));//输入源zip路径 
                    BufferedInputStream Bin=new BufferedInputStream(Zin); 
                    String Parent="F:\\"; //输出路径（文件夹目录） 
                    File Fout=null; 
                    ZipEntry entry; 
                    try { 
                        while((entry = Zin.getNextEntry())!=null && !entry.isDirectory()){ 
                            Fout=new File(Parent,entry.getName()); 
                            if(!Fout.exists()){ 
                                (new File(Fout.getParent())).mkdirs(); 
                            } 
                            FileOutputStream out=new FileOutputStream(Fout); 
                            BufferedOutputStream Bout=new BufferedOutputStream(out); 
                            int b; 
                            while((b=Bin.read())!=-1){ 
                                System.out.println((char)b);
                                Bout.write(b); 
                            } 
                            Bout.close(); 
                            out.close(); 
                            System.out.println(Fout+"解压成功");     
                        } 
                        Bin.close(); 
                        Zin.close(); 
                    } catch (IOException e) { 
                        e.printStackTrace(); 
                    } 
                } catch (FileNotFoundException e) { 
                    e.printStackTrace(); 
                } 
                long endTime=System.currentTimeMillis(); 
                System.out.println("耗费时间： "+(endTime-startTime)+" ms"); 
            }

**其次是关于文件常用的一个操作，读取目录下的所有文件，包括不同等级下的目录**

public static boolean readfile(String filepath)   {
            File file = new File(filepath);
            if (!file.isDirectory()) {
                    System.out.println("文件");
                    System.out.println("path=" + file.getPath());
                    System.out.println("absolutepath=" + file.getAbsolutePath());
                    System.out.println("name=" + file.getName());
    
            } else if (file.isDirectory()) {
                    System.out.println("文件夹");
                    String[] filelist = file.list();
                    for (int i = 0; i < filelist.length; i++) {
        
                            File readfile = new File(filepath + "\\" + filelist[i]);
                            if (!readfile.isDirectory()) {
                                    System.out.println("path=" + readfile.getPath());
                                    System.out.println("absolutepath="
                                                    + readfile.getAbsolutePath());
                                    System.out.println("name=" + readfile.getName());
    
                            } else if (readfile.isDirectory()) {
                                    readfile(filepath + "\\" + filelist[i]);
                            }
                    }
    
            }
            return true;
    }

**对超大文件的读取**

File file = new File(filepath);   
    BufferedInputStream fis = new BufferedInputStream(new FileInputStream(file));    
    BufferedReader reader = new BufferedReader(new InputStreamReader(fis,"utf-8"),5*1024*1024);// 用5M的缓冲读取文本文件  
    
    String line = "";
    while((line = reader.readLine()) != null){
    //TODO: write your business
    }