works

MathUtilities.java

@@ -11,7 +11,8 @@ public class MathUtilities {
      * @return sum of `baseValue` and `difference`
      */
     public Integer add(int baseValue, int difference) {
-        return null;
+        int solution = baseValue + difference;
+        return solution;
     }
 
     /**
@@ -20,7 +21,8 @@ public class MathUtilities {
      * @return sum of `baseValue` and `difference`
      */
     public Long add(long baseValue, long difference) {
-        return null;
+        long solution = baseValue + difference;
+        return solution;
     }
 
     /**
@@ -29,7 +31,8 @@ public class MathUtilities {
      * @return sum of `baseValue` and `difference`
      */
     public Short add(short baseValue, short difference) {
-        return null;
+        short solution = (short) (baseValue + difference);
+        return solution;
     }
 
     /**
@@ -38,7 +41,9 @@ public class MathUtilities {
      * @return sum of `baseValue` and `difference`
      */
     public Byte add(byte baseValue, byte difference) {
-        return null;
+        int first = baseValue + difference;
+        byte solution = (byte)first;
+        return solution;
     }
 
     /**
@@ -47,7 +52,8 @@ public class MathUtilities {
      * @return sum of `baseValue` and `difference`
      */
     public Float add(float baseValue, float difference) {
-        return null;
+        float solution = baseValue + difference;
+        return solution;
     }
 
     /**
@@ -56,7 +62,8 @@ public class MathUtilities {
      * @return sum of `baseValue` and `difference`
      */
     public Double add(double baseValue, double difference) {
-        return null;
+        double solution = baseValue + difference;
+        return solution;
     }
 
     /**
@@ -65,7 +72,8 @@ public class MathUtilities {
      * @return difference between `baseValue` and `difference`
      */
     public Integer subtract(int baseValue, int difference) {
-        return null;
+        int solution = baseValue - difference;
+        return solution;
     }
 
     /**
@@ -74,7 +82,8 @@ public class MathUtilities {
      * @return difference between `baseValue` and `difference`
      */
     public Long subtract(long baseValue, long difference) {
-        return null;
+        long solution = baseValue - difference;
+        return solution;
     }
 
     /**
@@ -83,7 +92,9 @@ public class MathUtilities {
      * @return difference between `baseValue` and `difference`
      */
     public Short subtract(short baseValue, short difference) {
-        return null;
+        int convert = (short) baseValue - difference;
+        short solution = (short) convert;
+        return solution;
     }
 
     /**
@@ -92,7 +103,9 @@ public class MathUtilities {
      * @return difference between `baseValue` and `difference`
      */
     public Byte subtract(byte baseValue, byte difference) {
-        return null;
+        int conversion = baseValue - difference;
+        byte solution = (byte) conversion;
+        return solution;
     }
 
     /**
@@ -101,7 +114,8 @@ public class MathUtilities {
      * @return difference between `baseValue` and `difference`
      */
     public Float subtract(float baseValue, float difference) {
-        return null;
+        float solution = baseValue - difference;
+        return solution;
     }
 
     /**
@@ -110,7 +124,8 @@ public class MathUtilities {
      * @return difference between `baseValue` and `difference`
      */
     public Double subtract(double baseValue, double difference) {
-        return null;
+        double solution = baseValue - difference;
+        return solution;
     }
 
 
@@ -120,7 +135,8 @@ public class MathUtilities {
      * @return division of `dividend` by `divisor
      */
     public Integer divide(int dividend, int divisor) {
-        return null;
+        int division = dividend / divisor;
+        return division;
     }
 
     /**
@@ -129,7 +145,8 @@ public class MathUtilities {
      * @return division of `dividend` by `divisor
      */
     public Long divide(long dividend, long divisor) {
-        return null;
+        long division = dividend / divisor;
+        return division;
     }
 
     /**
@@ -138,7 +155,9 @@ public class MathUtilities {
      * @return division of `dividend` by `divisor
      */
     public Short divide(short dividend, short divisor) {
-        return null;
+        int convert = dividend / divisor;
+        short solution = (short) convert;
+        return solution;
     }
 
     /**
@@ -147,7 +166,9 @@ public class MathUtilities {
      * @return division of `dividend` by `divisor
      */
     public Byte divide(byte dividend, byte divisor) {
-        return null;
+        int convert = dividend / divisor;
+        byte solution = (byte) convert;
+        return solution;
     }
 
     /**
@@ -156,7 +177,8 @@ public class MathUtilities {
      * @return division of `dividend` by `divisor
      */
     public Float divide(float dividend, float divisor) {
-        return null;
+        float solution = dividend / divisor;
+        return solution;
     }
 
     /**
@@ -165,7 +187,8 @@ public class MathUtilities {
      * @return division of `dividend` by `divisor
      */
     public Double divide(double dividend, double divisor) {
-        return null;
+        double solution = dividend / divisor;
+        return solution;
     }
 
 
@@ -175,7 +198,8 @@ public class MathUtilities {
      * @return product of `multiplicand` by `multiplier`
      */
     public Integer multiply(int multiplicand, int multiplier) {
-        return null;
+        int solution = multiplicand * multiplier;
+        return solution;
     }
 
     /**
@@ -184,7 +208,8 @@ public class MathUtilities {
      * @return product of `multiplicand` by `multiplier`
      */
     public Long multiply(long multiplicand, long multiplier) {
-        return null;
+        long solution = multiplicand * multiplier;
+        return solution;
     }
 
     /**
@@ -193,7 +218,9 @@ public class MathUtilities {
      * @return product of `multiplicand` by `multiplier`
      */
     public Short multiply(short multiplicand, short multiplier) {
-        return null;
+        int convert = multiplicand * multiplier;
+        short solution = (short) convert;
+        return solution;
     }
     /**
      * @param multiplicand value to be multiplied
@@ -201,7 +228,9 @@ public class MathUtilities {
      * @return product of `multiplicand` by `multiplier`
      */
     public Byte multiply(byte multiplicand, byte multiplier) {
-        return null;
+        int convert = multiplicand * multiplier;
+        byte solution = (byte) convert;
+        return solution;
     }
 
     /**
@@ -210,7 +239,8 @@ public class MathUtilities {
      * @return product of `multiplicand` by `multiplier`
      */
     public Float multiply(float multiplicand, float multiplier) {
-        return null;
+        float solution = multiplicand * multiplier;
+        return solution;
     }
 
     /**
@@ -219,7 +249,8 @@ public class MathUtilities {
      * @return product of `multiplicand` by `multiplier`
      */
     public Double multiply(double multiplicand, double multiplier) {
-        return null;
+        double solution = multiplicand * multiplier;
+        return solution;
     }
 
 
@@ -227,14 +258,16 @@ public class MathUtilities {
       * @return true
      */
     public Boolean returnTrue() {
-        return null;
+        boolean solution = true;
+        return solution;
     }
 
     /**
      * @return false
      */
     public Boolean returnFalse() {
-        return null;
+        boolean solution = false;
+        return solution;
     }
 
 }

PredicateUtilities.java

@@ -10,7 +10,10 @@ public class PredicateUtilities {
      * @return true if `x` is greater than `y`
      */
     public Boolean isGreaterThan(int x, int y) {
-        return null;
+        if (x > y) {
+            return true;}
+        else {
+            return false;}
     }
 
     /**
@@ -19,7 +22,10 @@ public class PredicateUtilities {
      * @return true if `x` is less than `y`
      */
     public Boolean isLessThan(int x, int y) {
-        return null;
+        if (x < y) {
+            return true;}
+        else {
+            return false;}
     }
 
     /**
@@ -28,7 +34,10 @@ public class PredicateUtilities {
      * @return true if `x` is greater than or equal to `y`
      */
     public Boolean isGreaterThanOrEqualTo(int x, int y) {
-        return null;
+        if (x >= y) {
+            return true;}
+        else {
+            return false;}
     }
 
     /**
@@ -37,6 +46,9 @@ public class PredicateUtilities {
      * @return true if `x` is less than or equal to `y`
      */
     public Boolean isLessThanOrEqualTo(int x, int y) {
-        return null;
+        if (x <= y) {
+            return true;}
+        else {
+            return false;}
     }
 }

StringUtilities.java

@@ -1,4 +1,6 @@
- 
+import java.lang.*; 
+import java.io.*; 
+import java.util.*;
 
 /**
  * Created by dan on 6/14/17.
@@ -8,7 +10,8 @@ public class StringUtilities {
      * @return `Hello World` as a string
      */
     public static String getHelloWorld() {
-        return null;
+        String solution = "Hello World";
+        return solution;
     }
 
     /**
@@ -17,7 +20,8 @@ public class StringUtilities {
      * @return the concatenation of two strings, `firstSegment`, and `secondSegment`
      */
     public static String concatenation(String firstSegment, String secondSegment){
-        return null;
+        String solution = firstSegment + secondSegment;
+        return solution;
     }
 
     /**
@@ -26,7 +30,9 @@ public class StringUtilities {
      * @return the concatenation of an integer, `firstSegment`, and a String, `secondSegment`
      */
     public static String concatenation(int firstSegment, String secondSegment){
-        return null;
+        String convert = Integer.toString(firstSegment);
+        String solution = convert + secondSegment;
+        return solution;
     }
 
     /**
@@ -34,7 +40,7 @@ public class StringUtilities {
      * @return the first 3 characters of `input`
      */
     public static String getPrefix(String input){
-        return null;
+        return input.substring(0,3);
     }
 
     /**
@@ -42,7 +48,7 @@ public class StringUtilities {
      * @return the last 3 characters of `input`
      */
     public static String getSuffix(String input){
-        return null;
+        return input.substring(input.length() - 3);
     }
 
     /**
@@ -51,7 +57,10 @@ public class StringUtilities {
      * @return the equivalence of two strings, `inputValue` and `comparableValue`
      */
     public static Boolean compareTwoStrings(String inputValue, String comparableValue){
-        return null;
+        if (inputValue == comparableValue) {
+            return true;} else {
+                return false;}
+                
     }
 
     /**
@@ -59,7 +68,13 @@ public class StringUtilities {
      * @return the middle character of `inputValue`
      */
     public static Character getMiddleCharacter(String inputValue){
-        return null;
+        int length = inputValue.length() - 1; // 6
+        int middle = length / 2; //3
+        String math = String.valueOf(middle + 1); //4
+        int halfway = Integer.valueOf(math); //4
+        String thechar = inputValue.substring(halfway - 1, halfway);
+        char itsthechar = thechar.charAt(0);
+        return itsthechar;
     }
 
     /**
@@ -67,7 +82,8 @@ public class StringUtilities {
      * @return the first sequence of characters
      */
     public static String getFirstWord(String spaceDelimitedString){
-        return null;
+        String[] splitem = spaceDelimitedString.split("\\s+");
+        return splitem[0];
     }
 
     /**
@@ -75,7 +91,8 @@ public class StringUtilities {
      * @return the second word of a string delimited by spaces.
      */
     public static String getSecondWord(String spaceDelimitedString){
-        return null;
+        String[] splitem = spaceDelimitedString.split("\\s+");
+        return splitem[1];
     }
 
     /**
@@ -83,6 +100,8 @@ public class StringUtilities {
      * @return an identical string with characters in reverse order.
      */
     public static String reverse(String stringToReverse){
-        return null;
+        StringBuilder easy = new StringBuilder();
+        easy.append(stringToReverse);
+        return easy.reverse().toString();
     }
 }

package.bluej

@@ -1,13 +1,13 @@
 #BlueJ package file
-editor.fx.0.height=0
-editor.fx.0.width=0
-editor.fx.0.x=0
-editor.fx.0.y=0
-objectbench.height=129
+editor.fx.0.height=709
+editor.fx.0.width=1001
+editor.fx.0.x=296
+editor.fx.0.y=23
+objectbench.height=128
 objectbench.width=1171
 package.divider.horizontal=0.6
-package.divider.vertical=0.7490774907749077
-package.editor.height=399
+package.divider.vertical=0.7509225092250923
+package.editor.height=400
 package.editor.width=1069
 package.editor.x=59
 package.editor.y=63