Java - Primitive Data Type Read

Description

Primitive Data Type Read

Demo

import java.io.Closeable;
import java.io.DataInputStream;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;

public class Main {
  public static void main(String[] args) {
    String srcFile = "primitives.dat";

    try (DataInputStream dis = new DataInputStream(new FileInputStream(srcFile))) {
      // Read the data in the same order they were written
      int intValue = dis.readInt();
      double doubleValue = dis.readDouble();
      boolean booleanValue = dis.readBoolean();
      String msg = dis.readUTF();

      System.out.println(intValue);
      System.out.println(doubleValue);
      System.out.println(booleanValue);
      System.out.println(msg);/* w w w .  j  av a 2  s. c o  m*/
    } catch (FileNotFoundException e) {
      FileUtil.printFileNotFoundMsg(srcFile);
    } catch (IOException e) {
      e.printStackTrace();
    }
  }
}

class FileUtil {
  // Prints the location details of a file
  public static void printFileNotFoundMsg(String fileName) {
    String workingDir = System.getProperty("user.dir");
    System.out.println("Could not find the file '" + fileName + "' in '"
        + workingDir + "' directory ");
  }

  // Closes a Closeable resource such as an input/output stream
  public static void close(Closeable resource) {
    if (resource != null) {
      try {
        resource.close();
      } catch (IOException e) {
        e.printStackTrace();
      }
    }
  }
}

Result