Java Question: Consider a maze made up of a rectangular array of squares. The maze will
contain a character (either +, -, or |) to represent a blocked square, and to form the walls of the
maze. Mazes will have only one entrance at the Coordinate (0, 1), with only one exit in the lower
right hand corner of the maze. Beginning at the entrance to the maze, find a path to the exit at the
bottom right of the maze. You may only move up, down, left, and right. Each square in the maze
can be in one of four states: clear (space), blocked (X), path (.), or visited (*). Initially, after the
maze has been read in from the file, each square will be either clear or blocked. If a square lies
on a successful path, mark it with a period. If you visit a square but it does not lead to a
successful path, mark it as visited with an asterisk.
Solution
import java.io.*;
class Maze
{
// Any MazeSquare field is true if the corresponding
// wall exists, and false otherwise.
class MazeSquare
{
public boolean hasTopWall;
public boolean hasRightWall;
public boolean hasLeftWall;
public boolean hasBottomWall;
public MazeSquare()
{
hasTopWall = hasRightWall = hasLeftWall = hasBottomWall = false;
}
}
// This Exception class will help pinpoint format errors in the data file.
class MazeFormatException extends Exception
{
public final static int noError = 0;
public final static int badRowAndColumnCounts = 1;
public final static int wrongNumberOfEntriesInRow = 2;
public final static int badEntry = 3;
public int lineNumber;
public int problem;
public MazeFormatException( int line, int prob )
{
lineNumber = line;
problem = prob;
}
}
// Number of rows and columns in the maze.
private int nRows;
private int nColumns;
// The array of maze squares themselves.
MazeSquare[][] square;
public static void main( String[] args )
{
if( args.length != 1 )
{
System.err.println( \"Usage: java Maze mazeFileName\" );
System.exit( 1 );
}
Maze knosos = null;
try
{
knosos = new Maze( args[0] );
}
catch( FileNotFoundException e )
{
System.err.println( \"Can\'t open \" + args[0] + \". Check your spelling.\" );
System.exit( 1 );
}
catch( IOException e )
{
System.err.println( \"Severe input error. I give up.\" );
System.exit( 1 );
}
catch( MazeFormatException e )
{
switch( e.problem )
{
case MazeFormatException.badRowAndColumnCounts:
System.err.println( args[0] + \", line \" + e.lineNumber + \": row and column counts
expected\" );
break;
case MazeFormatException.wrongNumberOfEntriesInRow:
System.err.println( args[0] + \", line \" + e.lineNumber + \": wrong number of entries\"
);
break;
case MazeFormatException.badEntry:
System.err.println( args[0] + \", line \" + e.lineNumber + \": non-hexadecimal digit
detected\" );
break;
default:
System.err.println( \"This should never get printed.\" );
break;
}
System.exit( 1 );
}
knosos.print( System.out );
}
public Maze()
{
square = null;
nRows = nColumns = 0;
}
public Maze( String fileName ) throws FileNotFoundException, IOException,
MazeFormatException
{
Buffered.
Unit 3 Emotional Intelligence and Spiritual Intelligence.pdf
Java Question Consider a maze made up of a rectangular array of squ.pdf
1. Java Question: Consider a maze made up of a rectangular array of squares. The maze will
contain a character (either +, -, or |) to represent a blocked square, and to form the walls of the
maze. Mazes will have only one entrance at the Coordinate (0, 1), with only one exit in the lower
right hand corner of the maze. Beginning at the entrance to the maze, find a path to the exit at the
bottom right of the maze. You may only move up, down, left, and right. Each square in the maze
can be in one of four states: clear (space), blocked (X), path (.), or visited (*). Initially, after the
maze has been read in from the file, each square will be either clear or blocked. If a square lies
on a successful path, mark it with a period. If you visit a square but it does not lead to a
successful path, mark it as visited with an asterisk.
Solution
import java.io.*;
class Maze
{
// Any MazeSquare field is true if the corresponding
// wall exists, and false otherwise.
class MazeSquare
{
public boolean hasTopWall;
public boolean hasRightWall;
public boolean hasLeftWall;
public boolean hasBottomWall;
public MazeSquare()
{
hasTopWall = hasRightWall = hasLeftWall = hasBottomWall = false;
}
}
// This Exception class will help pinpoint format errors in the data file.
class MazeFormatException extends Exception
{
public final static int noError = 0;
public final static int badRowAndColumnCounts = 1;
public final static int wrongNumberOfEntriesInRow = 2;
public final static int badEntry = 3;
2. public int lineNumber;
public int problem;
public MazeFormatException( int line, int prob )
{
lineNumber = line;
problem = prob;
}
}
// Number of rows and columns in the maze.
private int nRows;
private int nColumns;
// The array of maze squares themselves.
MazeSquare[][] square;
public static void main( String[] args )
{
if( args.length != 1 )
{
System.err.println( "Usage: java Maze mazeFileName" );
System.exit( 1 );
}
Maze knosos = null;
try
{
knosos = new Maze( args[0] );
}
catch( FileNotFoundException e )
{
System.err.println( "Can't open " + args[0] + ". Check your spelling." );
System.exit( 1 );
}
catch( IOException e )
{
System.err.println( "Severe input error. I give up." );
System.exit( 1 );
}
catch( MazeFormatException e )
3. {
switch( e.problem )
{
case MazeFormatException.badRowAndColumnCounts:
System.err.println( args[0] + ", line " + e.lineNumber + ": row and column counts
expected" );
break;
case MazeFormatException.wrongNumberOfEntriesInRow:
System.err.println( args[0] + ", line " + e.lineNumber + ": wrong number of entries"
);
break;
case MazeFormatException.badEntry:
System.err.println( args[0] + ", line " + e.lineNumber + ": non-hexadecimal digit
detected" );
break;
default:
System.err.println( "This should never get printed." );
break;
}
System.exit( 1 );
}
knosos.print( System.out );
}
public Maze()
{
square = null;
nRows = nColumns = 0;
}
public Maze( String fileName ) throws FileNotFoundException, IOException,
MazeFormatException
{
BufferedReader in = null;
in = new BufferedReader( new FileReader( fileName ) );
load( in );
in.close();
4. }
public void load( BufferedReader in ) throws MazeFormatException
{
String line;
String[] tokens;
int lineNumber = 0;
// Get the number of rows and columns. Protect
// against out-of-range values.
try
{
line = in.readLine();
lineNumber++;
tokens = line.split( "s+" );
nRows = Integer.parseInt( tokens[0] );
nColumns = Integer.parseInt( tokens[1] );
if( nRows <= 0 || nColumns <= 0 )
throw new Exception();
}
catch( Exception e )
{
throw new MazeFormatException( lineNumber,
MazeFormatException.badRowAndColumnCounts );
}
// Allocate the 2D array of MazeSquares.
square = new MazeSquare[nRows][nColumns];
for( int i=0; i < nRows; i++ )
for( int j=0; j < nColumns; j++ )
square[i][j] = new MazeSquare();
// Read the square values from input into the array of MazeSquares.
for( int i=0; i < nRows; i++ )
{
try
{
line = in.readLine();
lineNumber++;
5. tokens = line.split( "s+" );
if( tokens.length != nColumns )
throw new Exception();
}
catch( Exception e )
{
throw new MazeFormatException( lineNumber,
MazeFormatException.wrongNumberOfEntriesInRow );
}
for( int j=0; j < nColumns; j++ )
{
int squareValue;
try
{
squareValue = Integer.parseInt( tokens[j], 16 );
}
catch( NumberFormatException e )
{
throw new MazeFormatException( lineNumber, MazeFormatException.badEntry );
}
// These are "bitwise AND" operations. We'll discuss them in class.
square[i][j].hasTopWall = ((squareValue & 1) != 0);
square[i][j].hasRightWall = ((squareValue & 2) != 0);
square[i][j].hasBottomWall = ((squareValue & 4) != 0);
square[i][j].hasLeftWall = ((squareValue & 8) != 0);
}
}
}
public void print( PrintStream out )
{
int i, j;
for( i=0; i < nRows; i++ )
{
// Draw the top walls of this row of squares.
out.print( '+' );
![public int lineNumber;
public int problem;
public MazeFormatException( int line, int prob )
{
lineNumber = line;
problem = prob;
}
}
// Number of rows and columns in the maze.
private int nRows;
private int nColumns;
// The array of maze squares themselves.
MazeSquare[][] square;
public static void main( String[] args )
{
if( args.length != 1 )
{
System.err.println( "Usage: java Maze mazeFileName" );
System.exit( 1 );
}
Maze knosos = null;
try
{
knosos = new Maze( args[0] );
}
catch( FileNotFoundException e )
{
System.err.println( "Can't open " + args[0] + ". Check your spelling." );
System.exit( 1 );
}
catch( IOException e )
{
System.err.println( "Severe input error. I give up." );
System.exit( 1 );
}
catch( MazeFormatException e )](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)