ourdateutility.java

java 完全探索的随书源码

import java.util.Date;
import java.io.*;

public class OurDateUtility
{
  /**
   * Static utility method that takes an instance of the Date class and a
   * file name and serializes the Date instance to the file
   */
  public static void writeDateToFile( Date dateInstance, String fileName )
  {
    try
    {
      // Create the object stream on an output file stream
      FileOutputStream fileStream = new FileOutputStream( fileName, false );
      ObjectOutputStream objectStr = new ObjectOutputStream( fileStream );
      // write out the object
      objectStr.writeObject( dateInstance );

      // Close the resources
      objectStr.close();
      fileStream.close();
    }
    catch( FileNotFoundException ex )
    {
      ex.printStackTrace();
      System.out.println( "Could not create the file for some reason" );
      System.exit(-1);
    }
    catch( IOException ex )
    {
      ex.printStackTrace();
      System.out.println( "There was a problem writing the object to the stream" );
      System.exit(-1);
    }
  }
  /**
   * Static utility method that takes a file name and deserializes
   * a date instance from it and returns the Date instance
   */
  public static Date readDateFromFile( String fileName )
  {
    Date dateFromFile = null;
    try
    {
      // Create an Object input stream on an input file stream
      FileInputStream in = new FileInputStream( fileName );
      ObjectInputStream objectInStr = new ObjectInputStream( in );
      // read in the object
      Object obj = objectInStr.readObject();

      // Double check that it is the right type before casting
      if ( obj instanceof Date )
      {
        dateFromFile = (Date)obj;
      }
    }
    catch( ClassNotFoundException ex )
    {
      ex.printStackTrace();
    }
    catch( FileNotFoundException ex )
    {
      ex.printStackTrace();
    }
    catch( IOException ex )
    {
      ex.printStackTrace();
    }
    return dateFromFile;
  }
}