java编程代码

				
				import java.io.ObjectOutputStream;
				import java.io.FileOutputStream;
				import java.io.ObjectInputStream;
				import java.io.FileInputStream;
				import java.io.IOException;
				import java.io.FileNotFoundException;
				
				/**
				 Demonstrates binary file I/O of serializable class objects.
				*/
				public class ObjectIODemo
				{
				
				   public static void main(String[] args)
				   {
				
				      try
				      {
				          ObjectOutputStream outputStream =
				             new ObjectOutputStream(new FileOutputStream("datafile"));
				
				          SomeClass oneObject = new SomeClass(1, 'A');
				          SomeClass anotherObject = new SomeClass(42, 'Z');
				
				          outputStream.writeObject(oneObject);
				          outputStream.writeObject(anotherObject);
				
				          outputStream.close( );
				
				          System.out.println("Data sent to file.");
				      }
				      catch(IOException e)
				      {
				         System.out.println("Problem with file output.");
				      }
				
				      System.out.println(
				              "Now let's reopen the file and display the data.");
				
				      try
				      {
				          ObjectInputStream inputStream = 
				            new ObjectInputStream(new FileInputStream("datafile"));
				
				
				          SomeClass readOne = (SomeClass)inputStream.readObject( );
				          SomeClass readTwo = (SomeClass)inputStream.readObject( );
				
				          System.out.println("The following were read from the file:");
				          System.out.println(readOne);
				          System.out.println(readTwo);
				      }
				      catch(FileNotFoundException e)
				      {
				          System.out.println("Cannot find datafile.");
				      }
				      catch(ClassNotFoundException e)
				      {
				
				          System.out.println("Problems with file input.");
				      }
				      catch(IOException e)
				      {
				          System.out.println("Problems with file input.");
				      }
				
				      System.out.println("End of program.");
				   }
				}