calc

src/main/java/com/zipcodewilmington/scientificcalculator/Console.java

@@ -17,16 +17,25 @@ public static void println(String output, Object... args) {
 
     public static String getStringInput(String prompt) {
         Scanner scanner = new Scanner(System.in);
-        println(prompt);
+        print(prompt);
         String userInput = scanner.nextLine();
+        //scanner.close();
         return userInput;
     }
 
     public static Integer getIntegerInput(String prompt) {
-        return null;
+        Scanner scanner = new Scanner(System.in);
+        print(prompt);
+        Integer userinput = scanner.nextInt();
+        //scanner.close();
+        return userinput;
     }
 
     public static Double getDoubleInput(String prompt) {
-        return null;
+        Scanner scanner = new Scanner(System.in);
+        print(prompt);
+        Double userinput = scanner.nextDouble();
+        //scanner.close();
+        return userinput;
     }
 }

src/main/java/com/zipcodewilmington/scientificcalculator/CoreFeatures.java

@@ -0,0 +1,155 @@
+package com.zipcodewilmington.scientificcalculator;
+
+public class CoreFeatures {
+
+    //a state represening the value currently displayed on the calc 
+    private double displayValue;
+
+    //Update the display to ERR if an error occurs (ex: divide by 0)
+    private boolean errorState;
+
+    //initiate calculator with 0 as default 
+    public CoreFeatures () {
+        this.displayValue = 0.0;
+        //not an ERR
+        this.errorState=false;
+
+    }
+
+    //Get the current # on the display 
+    public double getDisplayValue() {
+        //pull the display value 
+        return this.displayValue;
+    }
+
+    //Check for errors
+    public boolean inErrorState() {
+        //pull the error state (is it true or false)
+        return this.errorState;
+    }
+
+    //Set display to the number entered 
+    public void setDisplay (double value) {
+        //(if ERR, skip the equation)
+        if (checkError()) return;
+        //reset the display value to the number entered
+        this.displayValue=value;
+
+    }
+
+    //Clear the display
+      public void clear () {
+
+        //set display to 0 and remove error
+        this.displayValue=0.0;
+        this.errorState=false;
+
+
+        // Clear terminal by printing lines to simulate clearing
+        for (int i = 0; i < 50; ++i) {
+            System.out.println();
+        }
+        System.out.println("Cleared");
+      }
+
+
+    //Add (if ERR, skip the equation)
+    public void add(double number) {
+        if (checkError()) return;
+        this.displayValue+=number;
+    }
+
+
+    //Subtract (if ERR, skip the equation)
+    public void subtract (double number) {
+        if (checkError()) return;
+        this.displayValue -= number;
+    }
+
+    //Multiply (if ERR, skip the equation)
+    public void multiply (double number) {
+        if (checkError()) return;
+        this.displayValue *= number;
+    }
+
+    //Divide (if ERR, skip the equation)
+    public void divide(double number) {
+        if (checkError()) return;
+        if(number ==0) {
+            setError();
+            return;
+        }
+        this.displayValue/=number;
+    }
+
+    //Caclulate the square (if ERR, skip the equation) 
+    public void square () {
+        if (checkError()) return;
+        this.displayValue=this.displayValue*this.displayValue;
+    }
+
+    //Calculate the square root (if ERR, skip the equation)
+    public void squareRoot() {
+        if (checkError()) return;
+        if (this.displayValue<0) {
+            setError();
+            return;
+        }
+        this.displayValue=Math.sqrt((this.displayValue));
+    }
+
+    //Calculate the variable exponentiation (if ERR, skip the equation)
+    public void exponentiation(double exponent) {
+        if (checkError()) return;
+        this.displayValue=Math.pow(this.displayValue, exponent);
+    }
+
+    //Calculate the inverse of the number (if ERR, skip the equation)
+    public void inverse() {
+        if (checkError()) return;
+        if (this.displayValue==0) {
+            setError();
+            return;
+        }
+        this.displayValue=1/this.displayValue;
+    }
+
+    //Caclulate the percentage of another number  NEW FEATURE #1
+    public void percentage(double percent) {
+        if (checkError()) return;
+        this.displayValue = (percent/this.displayValue)*100;
+
+    }
+
+    //Takes a decimal and returns the percentage NEW FEATURE #2
+    public void decimalToPercentage () {
+        if (checkError()) return;
+        this.displayValue*=100;
+
+    }
+
+    //Invert the sign of the number (switch between postive and negative)
+    //(if ERR, skip the equation)
+    public void inverseSign() {
+        if (checkError()) return;
+        this.displayValue=-this.displayValue;
+
+    }
+
+
+    //Set an error state so we can use it to compare 
+    private void setError() {
+        this.errorState=true; 
+    }
+
+    //check for an error before operation 
+    private boolean checkError() {
+        if (this.errorState) {
+            System.out.println("ERR");
+            return true;
+        }
+        return false;
+    }
+
+
+}