Rectangle.java

package Question20_13;

/* A class that represents a rectangular array of letters. */
public class Rectangle {
    
    // Rectangle data.
    public int height;
    public int length; 
    public char [][] matrix;

    /* Construct an "empty" rectangular array of letters, of height 0
     * and length specified by the argument.
     */
    public Rectangle(int l) {
        height = 0;
        length = l;
    }

    /* Construct a rectangular array of letters of the specified length
     * and height. The array is initially filled with "zero" characters
     * ('\u0000'), by default.
     */
    public Rectangle(int length, int height) {
        this.height = height;
        this.length = length;
        matrix = new char[height][length];
    }

    /* Construct a rectangular array of letters of the specified length
     * and height, and backed by the specified matrix of letters. (It is
     * assumed that the length and height specified as arguments are 
     * consistent with the array argument's dimensions.)
     */
    public Rectangle(int length, int height, char[][] letters) {
        this.height = letters.length;
        this.length = letters[0].length;
        matrix = letters;
    }

    /* Return the letter present at the specified location in the array.
     */
    public char getLetter (int i, int j) {
        return matrix[i][j];
    }
    
    public String getColumn(int i) {
		char[] column = new char[height];
		for (int j = 0; j < height; j++) {
			column[j] = getLetter(j, i);
		}
		return new String(column);
    }
    
    public boolean isComplete(int l, int h, WordGroup groupList) {
		// Check if we have formed a complete rectangle.
		if (height == h) {
			// Check if each column is a word in the dictionary.
			for (int i = 0; i < l; i++) {
				String col = getColumn(i);
				if (!groupList.containsWord(col)) {
					return false; // Invalid rectangle.
				}
			}
			return true; // Valid Rectangle!
		}
		return false;
    }
    
    public boolean isPartialOK(int l, Trie trie) {
    	if (height == 0) {
    		return true;
    	}
		for (int i = 0; i < l ; i++ ) {
			String col = getColumn(i);
			if (!trie.contains(col)) {
				return false; // Invalid rectangle.
			}
		}
		return true;
    }

    /* If the length of the argument s is consistent with that of this
     * Rectangle object, then return a Rectangle whose matrix is constructed by
     * appending s to the underlying matrix. Otherwise, return null. The
     * underlying matrix of this Rectangle object is /not/ modified.
     */
    public Rectangle append(String s) {
        if (s.length() == length) {
            char temp[][] = new char[height + 1][length];
            for (int i = 0; i < height; i++) {
                for (int j = 0; j < length; j++) {
                    temp[i][j] = matrix[i][j];
                }
            }
            s.getChars(0, length, temp[height], 0);

            return new Rectangle(length, height + 1, temp);
        }
        return null;
    }

    /* Print the rectangle out, row by row. */
    public void print() {
        for (int i = 0; i < height ; i++) {
            for (int j = 0; j < length; j++) {
                System.out.print(matrix[i][j]);
            }
            System.out.println(" ");
        }
    }

}