Question

I am trying to copy a 5mb database file to data folder from raw folder of my application.

I can copy it some times successfully.But after that i cannot click on images, while clicking i am getting OutOfMemory-exception.

so am trying to clear heap memory. is there any way to do that.

private void copyFromZipFile() throws IOException{
     InputStream is = mycontext.getResources().openRawResource(R.raw.dbfile);
         // Path to the just created empty db
         File outFile = new File(DB_PATH ,DB_NAME);
          //Open the empty db as the output stream
         OutputStream myOutput = new FileOutputStream(outFile.getAbsolutePath());
         ZipInputStream zis = new ZipInputStream(new BufferedInputStream(is));
          try {
              ZipEntry ze;
              while ((ze = zis.getNextEntry()) != null) {
                  ByteArrayOutputStream baos = new ByteArrayOutputStream();
                  byte[] buffer = new byte[1024];
                  int count;
                  while ((count = zis.read(buffer)) != -1) {
                      try
                      {
                      baos.write(buffer, 0, count);
                     Log.d("", "writing..."+buffer.toString());
                      }catch (Exception e) {
                        // TODO: handle exception
                          Log.v("","Error writing"+e );
                    }
                  }
                  baos.writeTo(myOutput);


              }
          } finally {
              zis.close();
              myOutput.flush();
              myOutput.close();
              is.close();
          }
        }

Answer 1

In your first while-loop, you are recreating the ByteArrayOutputStream for every iteration. You are not closing it and you don’t explicitly set it to null after you’re done, so this is a Memory-Leak because the garbage-collector can’t collect the instance.

A better approach would be moving the creation of baos, buffer and count out of the loop and using the reset()-method on the ByteArrayOutputStream after you wrote to the OutputStream.