Comment créer un fichier zip en Java

Question

J'ai un fichier texte dynamique qui extrait le contenu d'une base de données en fonction de la requête de l'utilisateur. Je dois écrire ce contenu dans un fichier texte et le zipper dans un dossier dans une servlet. Comment dois-je m'y prendre ?

Answer 1

Le contrôleur Spring boot, zippe les fichiers dans un répertoire, et peut être téléchargé.

@RequestMapping(value = "/files.zip")
@ResponseBody
byte[] filesZip() throws IOException {
    File dir = new File("./");
    File[] filesArray = dir.listFiles();
    if (filesArray == null || filesArray.length == 0)
        System.out.println(dir.getAbsolutePath() + " have no file!");
    ByteArrayOutputStream bo = new ByteArrayOutputStream();
    ZipOutputStream zipOut= new ZipOutputStream(bo);
    for(File xlsFile:filesArray){
        if(!xlsFile.isFile())continue;
        ZipEntry zipEntry = new ZipEntry(xlsFile.getName());
        zipOut.putNextEntry(zipEntry);
        zipOut.write(IOUtils.toByteArray(new FileInputStream(xlsFile)));
        zipOut.closeEntry();
    }
    zipOut.close();
    return bo.toByteArray();
}

Answer 2

El java.util.zip contient des classes permettant de créer des fichiers Zip à partir de Java. Cela correspond-il à ce que vous recherchez ?

Answer 3

C'est ainsi que l'on crée un fichier zip à partir d'un fichier source :

String srcFilename = "C:/myfile.txt";
String zipFile = "C:/myfile.zip";

try {
    byte[] buffer = new byte[1024];
    FileOutputStream fos = new FileOutputStream(zipFile);
    ZipOutputStream zos = new ZipOutputStream(fos);         
    File srcFile = new File(srcFilename);
    FileInputStream fis = new FileInputStream(srcFile);
    zos.putNextEntry(new ZipEntry(srcFile.getName()));          
    int length;
    while ((length = fis.read(buffer)) > 0) {
        zos.write(buffer, 0, length);
    }
    zos.closeEntry();
    fis.close();
    zos.close();            
}
catch (IOException ioe) {
    System.out.println("Error creating zip file" + ioe);
}

Answer 4

public static void main(String args[])
{
    omtZip("res/", "omt.zip");
}
public static void omtZip(String path,String outputFile)
{
    final int BUFFER = 2048;
    boolean isEntry = false;
    ArrayList<String> directoryList = new ArrayList<String>();
    File f = new File(path);
    if(f.exists())
    {
    try {
            FileOutputStream fos = new FileOutputStream(outputFile);
            ZipOutputStream zos = new ZipOutputStream(new BufferedOutputStream(fos));
            byte data[] = new byte[BUFFER];

            if(f.isDirectory())
            {
               //This is Directory
                do{
                    String directoryName = "";
                    if(directoryList.size() > 0)
                    {
                        directoryName = directoryList.get(0);
                        System.out.println("Directory Name At 0 :"+directoryName);
                    }
                    String fullPath = path+directoryName;
                    File fileList = null;
                    if(directoryList.size() == 0)
                    {
                        //Main path (Root Directory)
                        fileList = f;
                    }else
                    {
                        //Child Directory
                        fileList = new File(fullPath);
                    }
                    String[] filesName = fileList.list();

                    int totalFiles = filesName.length;
                    for(int i = 0 ; i < totalFiles ; i++)
                    {
                        String name = filesName[i];
                        File filesOrDir = new File(fullPath+name);
                        if(filesOrDir.isDirectory())
                        {
                            System.out.println("New Directory Entry :"+directoryName+name+"/");
                            ZipEntry entry = new ZipEntry(directoryName+name+"/");
                            zos.putNextEntry(entry);
                            isEntry = true;
                            directoryList.add(directoryName+name+"/");
                        }else
                        {
                            System.out.println("New File Entry :"+directoryName+name);
                            ZipEntry entry = new ZipEntry(directoryName+name);
                            zos.putNextEntry(entry);
                            isEntry = true;
                            FileInputStream fileInputStream = new FileInputStream(filesOrDir);
                            BufferedInputStream bufferedInputStream = new BufferedInputStream(fileInputStream, BUFFER);
                            int size = -1;
                            while(  (size = bufferedInputStream.read(data, 0, BUFFER)) != -1  )
                            {
                                zos.write(data, 0, size);
                            }
                            bufferedInputStream.close();
                        }
                    }
                    if(directoryList.size() > 0 && directoryName.trim().length() > 0)
                    {
                        System.out.println("Directory removed :"+directoryName);
                        directoryList.remove(0);
                    }

                }while(directoryList.size() > 0);
            }else
            {
                //This is File
                //Zip this file
                System.out.println("Zip this file :"+f.getPath());
                FileInputStream fis = new FileInputStream(f);
                BufferedInputStream bis = new BufferedInputStream(fis,BUFFER);
                ZipEntry entry = new ZipEntry(f.getName());
                zos.putNextEntry(entry);
                isEntry = true;
                int size = -1 ;
                while(( size = bis.read(data,0,BUFFER)) != -1)
                {
                    zos.write(data, 0, size);
                }
            }               

            //CHECK IS THERE ANY ENTRY IN ZIP ? ----START
            if(isEntry)
            {
              zos.close();
            }else
            {
                zos = null;
                System.out.println("No Entry Found in Zip");
            }
            //CHECK IS THERE ANY ENTRY IN ZIP ? ----START
        }catch(Exception e)
        {
            e.printStackTrace();
        }
    }else
    {
        System.out.println("File or Directory not found");
    }
 }    

}

Answer 5

Étant donné que exportPath y queryResults en tant que variables String, le bloc suivant crée un results.zip fichier sous exportPath et écrit le contenu de queryResults à un results.txt dans le fichier zip.

URI uri = URI.create("jar:file:" + exportPath + "/results.zip");
Map<String, String> env = Collections.singletonMap("create", "true");

try (FileSystem zipfs = FileSystems.newFileSystem(uri, env)) {
  Path filePath = zipfs.getPath("/results.txt");
  byte[] fileContent = queryResults.getBytes();

  Files.write(filePath, fileContent, StandardOpenOption.CREATE);
}