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Tech Talk 0:

In the first challenge, I learned how to use try-catch to handle different types of exceptions. I used a String array to create a dynamic menu. I handled two exceptions to ensure that the user enters a number and that it is within bounds, as seen below:

try {
            System.out.println(menu_items[Integer.parseInt(input)-1]);
        } catch (NumberFormatException e) {
            System.out.println("Make sure to enter a number as your choice!");
        }catch (ArrayIndexOutOfBoundsException a){
            System.out.println("Please enter a choice between 1 and " + menu_items.length);
        }

In the second challenge (IntByReference), I created a swapper method. Since each integer is a member of an object, i used getter and setter methods to compare the two variables and assign new values to them. I used a temp variable to perform the switch between the two values. I also overrode the toString() method to display the integer value instead of the object’s memory address.

public int getvalue(){
        return value;
    }

    public void setvalue(int a){
        value = a;
    }

    public void swapToLowHighOrder(IntByReference num){
        if (num.getvalue() < value){
            int temp = num.getvalue();
            num.setvalue(value);
            value = temp;
        }
    }

    public String toString(){
        return Integer.toString(value);
    }

In the third challenge, I practiced creating a custom toString() method to display a formatted string. My toString method consisted of two for loops: one traversed a 2D array forward (left-to-right, top-to-bottom) and one did so backwards (right-to-left, bottom-to-top). I also used methods to convert int to hexadecmial and used conditionals to format the numpad correctly.

for(int i = 0; i < matrix.length; i++){
            for (int j = 0; j < matrix[i].length; j++){
                if(matrix[i][j] < 0){output += "  ";}
                else{output += Integer.toHexString(matrix[i][j]) + " ";}
            }
            output += "\n";
    }
        output += "\n\n";

        for (int a = matrix.length-1; a >= 0; a--){
            for (int b = matrix[a].length-1; b >= 0; b--){
                if(matrix[a][b]<0){output += "  ";}
                else{output += Integer.toHexString(matrix[a][b]) + " ";}
            }
            output += "\n";
        }

        return output;
    }