Java I/O How to - Copy Characters between FileReader and FileWriter








Question

We would like to know how to copy Characters between FileReader and FileWriter.

Answer

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import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;

public class CopyCharacters {
  public static void main(String[] args) throws IOException {
    FileReader inputStream = null;
    FileWriter outputStream = null;

    try {
      inputStream = new FileReader("xanadu.txt");
      outputStream = new FileWriter("characteroutput.txt");

      int c;
      while ((c = inputStream.read()) != -1) {
        outputStream.write(c);
      }
    } finally {
      if (inputStream != null) {
        inputStream.close();
      }
      if (outputStream != null) {
        outputStream.close();
      }
    }
  }
}