CS 596 Client-Server Programming
Java Files

1. Streams and Files
   1. InputStream
   2. PrintStream
   3. File
   4. FileInputStream
   5. FileOutputStream
   6. Reading Files - Simple Way
   7. ASCIIInputStream

class  PrintStreamExample
	{
	public  static  void  main( String  args[] )
		{
		System.out.println(  "Hi Mom"  );
		}
	}

Creates a new PrintStream.

Creates a new PrintStream, with auto flushing.

Flushes the print stream and returns whether or not there was an error on the output stream.

class  PoorPrint
	{
	String  name  =  "sam";
	}

class  FancyPrint
	{
	String  name  =  "pete";

	public  String  toString()
		{
		return  "FancyPrint( "  +  name  +  " )";
		}
	}

class  TestPrint
	{
	public  static  void  main( String  args[]  )
		{
		PoorPrint  outOfIt  =  new  PoorPrint();
		FancyPrint  cool  =  new FancyPrint();

		System.out.println(  outOfIt  );
		System.out.println( cool  );
		}
	}

import java.io.*;
class  FileExamples
	{
	public  static  void  main( String  args[]  )
		{
		// New files
		File  classDirectory  =  new File(  "cs596"  );
		classDirectory.mkdir();			// Did not exist prior

		File  gradeFile  =  new File( "cs596", "grades.text"  );
		gradeFile.mkdir();				// Did not exist prior

		File  lectureNotes  =  new File( "cs596/lectures.text" );
		lectureNotes.mkdir();				// Did not exist prior

		// Existing file
		File  sourceFile  =  new File( "FileExamples.java" );

		String[]  fileList  =  classDirectory.list();
		for (  int fileNum = 0;  fileNum < fileList.length; fileNum++ )
			System.out.print(  fileList[ fileNum ] + "\t" );
		System.out.println();

		System.out.println(  classDirectory.getAbsolutePath()  );
		System.out.println(  gradeFile.exists()  );
		System.out.println(  gradeFile.getParent()  );
		System.out.println(  sourceFile.length()  );
		System.out.println(  sourceFile.lastModified()  );
		gradeFile.delete();
		}
	}

import java.io.*;
class  MakeDirectoriesExamples
	{
	public  static  void  main( String  args[]  )
		{

		// Does nothing if test/this does not exist
		File  a  =  new File(  "test/this/out"  );
		a.mkdir();


		// creates all four directories 
		File  b  =  new File( "second/test/of/this"  );
		b.mkdirs();
		}
	}


import java.io.*;
class  MachineIndependentFileNames
	{
	public  static  void  main( String  args[]  )
		{
		String  gradeFile  =  "/home/ma/whitney/cs596/grades"
		gradeFile  =  gradeFile.replace( '/', File.separator );
		System.out.println(  gradeFile  );
		}
	}

Creates an input file with the specified system dependent file name.

Creates an input file from the specified File object.

Creates an output file with the specified system dependent file name.

Creates an output file with the specified File object.

import java.io.*;
class  ReadingFileExample
	{
	public  static  void  main( String  args[]  )
		{
		File  sourceFile  =  new File( "ReadingFileExample.java" );
		FileInputStream inputFile = new FileInputStream( sourceFile);
		ASCIIInputStream  cin = new ASCIIInputStream( inputFile );

		for  ( int  k = 1 ;  k  <  10;  k++ )
			System.out.println(  cin.readWord()  )

		for  ( int  k = 1 ;  k  <  10;  k++ )
			System.out.println(  cin.readLine()  )
		}
	}

import java.io.*;
import sdsu.io.*;
class  WritingToFileExample
	{
	public  static  void  main( String  args[]  )
		{
		FileOutputStream writeFile = 
						new FileOutputStream( "newFile");
		PrintStream  cout = new PrintStream( inputFile );

		cout.println( "Save this for me");
		}
	}

Creates a new ASCIIInputStream.