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Android Android Data Persistence File Storage Writing to Internal Storage

Posted by MUZ140854 Gladness Njanji
MUZ140854 Gladness Njanji
4,139 Points

The following code is similar to what you just wrote. Modify this code to only write the file if it does not already exi

i keep getting errors but i dont see were im going wrong

FileUtilities.java 
import java.io.InputStream;
import java.io.FileNotFoundException;
import java.io.IOException;

public class FileUtilities {

  public static boolean copyResult;

  public static void saveAssetImage(Context context, String assetName) {
    File fileToWrite = new File(context.getFilesDir(), assetName);
    AssetManager assetManager = context.getAssets();
if(fileToWrite.exists()){
        copyResult = copyFile(in, out);
      }

    try {
      InputStream in = assetManager.open(assetName);
      FileOutputStream out = new FileOutputStream(fileToWrite);
      copyResult = copyFile(in, out);
    } catch(FileNotFoundException e) {
      e.printStackTrace();
    } catch (IOException e) {
      e.printStackTrace();
    }
  }

  private static boolean copyFile(InputStream in, FileOutputStream out) {
    // Copy magic intentionally omitted
    return true;
  }
}

1 Answer

Ryan Ruscett
Ryan Ruscett
23,309 Points
Ryan Ruscett
Ryan Ruscett
23,309 Points

hey, you are close. See, the error you get is "what is in and what is out?" Because they are not defined yet. You are copying a file if the file does not exist.

file.exists() returns true if it does exist, we only want to copy when it does NOT exist.

so (!file.exists()) copy the files.

This has to go underneath the input and output streams or else I have not yet defined what to copy. So check out the code I have below.

import java.io.InputStream;
import java.io.FileNotFoundException;
import java.io.IOException;

public class FileUtilities {

  public static boolean copyResult;

  public static void saveAssetImage(Context context, String assetName) {
    File fileToWrite = new File(context.getFilesDir(), assetName);
    AssetManager assetManager = context.getAssets();

  try {
      InputStream in = assetManager.open(assetName);
      FileOutputStream out = new FileOutputStream(fileToWrite);

  ////////////////////////////////////////////////////////////////    
      if(!fileToWrite.exists()) {
        copyResult = copyFile(in, out);
      }
   ///////////////////////////////////////////////////////////////  

 } catch(FileNotFoundException e) {
      e.printStackTrace();
    } catch (IOException e) {
      e.printStackTrace();
    }
  }

 private static boolean copyFile(InputStream in, FileOutputStream out) {
    // Copy magic intentionally omitted
    return true;
  }
}
MUZ140854 Gladness Njanji
MUZ140854 Gladness Njanji
4,139 Points

aww thanx alot it worked!!