How to read file from ZIP using InputStream?

Question

I must get file content from ZIP archive (only one file, I know its name) using SFTP. The only thing I'm having is ZIP's InputStream. Most examples show how get content using this statement:

ZipFile zipFile = new ZipFile("location"); 

But as I said, I don't have ZIP file on my local machine and I don't want to download it. Is an InputStream enough to read?

UPD: This is how I do:

import java.util.zip.ZipInputStream;  import com.jcraft.jsch.Channel; import com.jcraft.jsch.ChannelSftp; import com.jcraft.jsch.JSch; import com.jcraft.jsch.Session;  public class SFTP {       public static void main(String[] args) {          String SFTPHOST = "host";         int SFTPPORT = 3232;         String SFTPUSER = "user";         String SFTPPASS = "mypass";         String SFTPWORKINGDIR = "/dir/work";         Session session = null;         Channel channel = null;         ChannelSftp channelSftp = null;         try {             JSch jsch = new JSch();             session = jsch.getSession(SFTPUSER, SFTPHOST, SFTPPORT);             session.setPassword(SFTPPASS);             java.util.Properties config = new java.util.Properties();             config.put("StrictHostKeyChecking", "no");             session.setConfig(config);             session.connect();             channel = session.openChannel("sftp");             channel.connect();             channelSftp = (ChannelSftp) channel;             channelSftp.cd(SFTPWORKINGDIR);             ZipInputStream stream = new ZipInputStream(channelSftp.get("file.zip"));             ZipEntry entry = zipStream.getNextEntry();             System.out.println(entry.getName); //Yes, I got its name, now I need to get content         } catch (Exception ex) {             ex.printStackTrace();         } finally {             session.disconnect();             channelSftp.disconnect();             channel.disconnect();         }       } } 

Answer 1

Below is a simple example on how to extract a ZIP File, you will need to check if the file is a directory. But this is the simplest.

The step you are missing is reading the input stream and writing the contents to a buffer which is written to an output stream.

// Expands the zip file passed as argument 1, into the // directory provided in argument 2 public static void main(String args[]) throws Exception {     if(args.length != 2)     {         System.err.println("zipreader zipfile outputdir");         return;     }      // create a buffer to improve copy performance later.     byte[] buffer = new byte[2048];      // open the zip file stream     InputStream theFile = new FileInputStream(args[0]);     ZipInputStream stream = new ZipInputStream(theFile);     String outdir = args[1];      try     {          // now iterate through each item in the stream. The get next         // entry call will return a ZipEntry for each file in the         // stream         ZipEntry entry;         while((entry = stream.getNextEntry())!=null)         {             String s = String.format("Entry: %s len %d added %TD",                             entry.getName(), entry.getSize(),                             new Date(entry.getTime()));             System.out.println(s);              // Once we get the entry from the stream, the stream is             // positioned read to read the raw data, and we keep             // reading until read returns 0 or less.             String outpath = outdir + "/" + entry.getName();             FileOutputStream output = null;             try             {                 output = new FileOutputStream(outpath);                 int len = 0;                 while ((len = stream.read(buffer)) > 0)                 {                     output.write(buffer, 0, len);                 }             }             finally             {                 // we must always close the output file                 if(output!=null) output.close();             }         }     }     finally     {         // we must always close the zip file.         stream.close();     } } 

Code excerpt came from the following site:

http://www.thecoderscorner.com/team-blog/java-and-jvm/12-reading-a-zip-file-from-java-using-zipinputstream#.U4RAxYamixR