Unzip zip file using java.util.zip

Example to unzip /mnt/sdcard/test/test.zip file to /mnt/sdcard/test/unzip/ folder.

package com.AndroidUnZip;

import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.zip.ZipEntry;
import java.util.zip.ZipInputStream;

import android.app.Activity;
import android.os.Bundle;
import android.os.Environment;
import android.widget.Toast;

public class AndroidUnZipActivity extends Activity {
 
 String extStorageDirectory;
 final String testDir = "/test";
 final String unzipDir = "/unzip/";
 final String orgZipFile = "test.zip";
 String srcFile;
 String targetDir;
 
  /** Called when the activity is first created. */
  @Override
  public void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.main);
    
      CheckExtStorageDirectory();
      unzip();
      Toast.makeText(AndroidUnZipActivity.this,
     "Unzip finished!",
     Toast.LENGTH_LONG).show();
    

  }

  private void CheckExtStorageDirectory(){
   extStorageDirectory = Environment.getExternalStorageDirectory().toString();
   srcFile = extStorageDirectory + testDir + "/" + orgZipFile;
   targetDir = extStorageDirectory + testDir + unzipDir;
   Toast.makeText(AndroidUnZipActivity.this,
     srcFile + "\n\n" + targetDir,
     Toast.LENGTH_LONG).show();  
   
  }

  private void unzip(){
   
   final int BUFFER_SIZE = 4096;
   BufferedOutputStream bufferedOutputStream = null;
      FileInputStream fileInputStream;
    
      try {
   fileInputStream = new FileInputStream(srcFile);
   
   ZipInputStream zipInputStream = new ZipInputStream(new BufferedInputStream(fileInputStream));
         ZipEntry zipEntry;
       
         while ((zipEntry = zipInputStream.getNextEntry()) != null){
          String zipEntryName = zipEntry.getName();
             File file = new File(targetDir + zipEntryName);
           
             if (file.exists()){
              
             }else{
              if(zipEntry.isDirectory()){
               file.mkdirs();
              }else{
               byte buffer[] = new byte[BUFFER_SIZE];
               
               FileOutputStream fileOutputStream = new FileOutputStream(file);
                     bufferedOutputStream
                      = new BufferedOutputStream(fileOutputStream, BUFFER_SIZE);
                     int count;
                   
                     while ((count = zipInputStream.read(buffer, 0, BUFFER_SIZE)) != -1) {
                             bufferedOutputStream.write(buffer, 0, count);      
                     }
                   
                     bufferedOutputStream.flush();
                     bufferedOutputStream.close();
              }
             }
         }
         zipInputStream.close();
       
  } catch (FileNotFoundException e) {
   // TODO Auto-generated catch block
   e.printStackTrace();
  }catch (IOException e) {
   // TODO Auto-generated catch block
   e.printStackTrace();
  }
  }

}

To create folder and save unzipped files in sdcard, AndroidManifest.xml have to be modified to add permission of "android.permission.WRITE_EXTERNAL_STORAGE".

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
  package="com.AndroidUnZip"
  android:versionCode="1"
  android:versionName="1.0" >

  <uses-sdk android:minSdkVersion="10" />
  <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>

  <application
      android:icon="@drawable/ic_launcher"
      android:label="@string/app_name" >
      <activity
          android:name=".AndroidUnZipActivity"
          android:label="@string/app_name" >
          <intent-filter>
              <action android:name="android.intent.action.MAIN" />

              <category android:name="android.intent.category.LAUNCHER" />
          </intent-filter>
      </activity>
  </application>

</manifest>