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public void fio52_ncence1(String filename){
	// Identify a file by its path
    Path file1 = Paths.get(filename);
 
 
    // Open the file for writing
    try(BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(Files.newOutputStream(file1)))) {
        // Write to file...
    } catch (Exception e) {
    	System.out.println("Exception during file access" + e);
    } 
    // Close the file
    /*
     * A race condition here allows for an attacker to switch
     * out the file for another
     */

    // Reopen the file for reading
    Path file2 = Paths.get(filename);
    
    
    try(BufferedReader br = new BufferedReader(new InputStreamReader(Files.newInputStream(file2)))){
        String line;
        while ((line = br.readLine()) != null) {
            System.out.println(line);
        }
    } catch (Exception e) {
        System.out.println("Exception during file access" + e);
    }
}

public void fio52_nce1nce2(String filename){
    // Identify a file by its path
    Path file1 = Paths.get(filename);
    // Open the file for writing
    try(BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(Files.newOutputStream(file1)))) {
            // Write to file
    } catch (Exception e) {
      System.out.println("Exception during file access" + e);
    } 
    // ...
    // Reopen the file for reading
    Path file2 = Paths.get(filename);
    if (!Files.isSameFile(file1, file2)) {
      System.out.println("File tampered with");
      // Handle error
    }
    try(BufferedReader br = new BufferedReader(new InputStreamReader(Files.newInputStream(file2)))) { 
            String line;
            while ((line = br.readLine()) != null) {
                    System.out.println(line);
            }
    } catch (Exception e) {
      System.out.println("Exception during file access" + e);
    }
}

public void fio52_cecs1(String filename) throws IOException{
   // Identify a file by its path
   Path file1 = Paths.get(filename);
   BasicFileAttributes attr1 = Files.readAttributes(file1, BasicFileAttributes.class);
   FileTime creation1 = attr1.creationTime();
   FileTime modified1 = attr1.lastModifiedTime();

   // Open the file for writing
   try(BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(Files.newOutputStream(file1)))) {
           // Write to file...
   } catch (Exception e){
           System.out.println("Exception during file access" + e);
   } 
   // Reopen the file for reading
   Path file2 = Paths.get(filename);
   BasicFileAttributes attr2 = Files.readAttributes(file2, BasicFileAttributes.class);
   FileTime creation2 = attr2.creationTime();
   FileTime modified2 = attr2.lastModifiedTime();
   if ( (!creation1.equals(creation2)) || (!modified1.equals(modified2)) ) {
     System.out.println("File tampered with");
     // Handle error
   }
   try(BufferedReader br = new BufferedReader( new InputStreamReader(Files.newInputStream(file2)))){
		String line;
        while ((line = br.readLine()) != null) {
        	System.out.println(line);
        }
   } catch (Exception e){
       System.out.println("Exception during file access" + e);
   }
}

public void fio52_ce1cs2(String filename) throws IOException{
    // Identify a file by its path
    Path file1 = Paths.get(filename);
    BasicFileAttributes attr1 = Files.readAttributes(file1, BasicFileAttributes.class);
    Object key1 = attr1.fileKey();
    // Open the file for writing
    try(BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(Files.newOutputStream(file1)))) {
            // Write to file
    } catch (Exception e) {
    	System.out.println("Exception during file access" + e);
    } 
    // Reopen the file for reading
    Path file2 = Paths.get(filename);
    BasicFileAttributes attr2 = Files.readAttributes(file2, BasicFileAttributes.class);
    Object key2 = attr2.fileKey();

    if ( !key1.equals(key2) ) {
      System.out.println("File tampered with");
      // Handle error
    }

    try(BufferedReader br = new BufferedReader(new InputStreamReader(Files.newInputStream(file2)))) {
    	String line;
        while ((line = br.readLine()) != null) {
        	System.out.println(line);
        }
    } catch (Exception e) {
        System.out.println("Exception during file access" + e);
    }
} 

public void fio52_ce2cs3(String filename) throws IOException{
    // Identify a file by its path
    RandomAccessFile file = new RandomAccessFile( filename, "rw");

    // Write to file...

    // Go back to beginning and read contents
    file.seek(0);
    try {
      while (true) {
        String s = file.readUTF();
        System.out.print(s);
      }
    } catch (EOFException x) {
      // Ignore, this breaks out of while loop
    }
    br.close();
}