From 9735c8c093ab13f69d00edef5eac84ca27909ea2 Mon Sep 17 00:00:00 2001 From: amdegregorio Date: Sat, 3 Oct 2020 17:07:52 -0400 Subject: [PATCH] BAEL-4503 --- .../constantspatterns/Calculator.java | 37 +++++++++++++++++++ .../CalculatorConstants.java | 10 +++++ .../constantspatterns/GeometryCalculator.java | 32 ++++++++++++++++ .../calculations/MathConstants.java | 16 ++++++++ .../ConstantPatternUnitTest.java | 23 ++++++++++++ 5 files changed, 118 insertions(+) create mode 100644 core-java-modules/core-java-lang-3/src/main/java/com/baeldung/constantspatterns/Calculator.java create mode 100644 core-java-modules/core-java-lang-3/src/main/java/com/baeldung/constantspatterns/CalculatorConstants.java create mode 100644 core-java-modules/core-java-lang-3/src/main/java/com/baeldung/constantspatterns/GeometryCalculator.java create mode 100644 core-java-modules/core-java-lang-3/src/main/java/com/baeldung/constantspatterns/calculations/MathConstants.java create mode 100644 core-java-modules/core-java-lang-3/src/test/java/com/baeldung/constantspatterns/ConstantPatternUnitTest.java diff --git a/core-java-modules/core-java-lang-3/src/main/java/com/baeldung/constantspatterns/Calculator.java b/core-java-modules/core-java-lang-3/src/main/java/com/baeldung/constantspatterns/Calculator.java new file mode 100644 index 0000000000..78b51c1c93 --- /dev/null +++ b/core-java-modules/core-java-lang-3/src/main/java/com/baeldung/constantspatterns/Calculator.java @@ -0,0 +1,37 @@ +package com.baeldung.constantspatterns; + +public class Calculator { + public static final double PI = 3.14159265359; + private static final double UPPER_LIMIT = 0x1.fffffffffffffP+1023; + + public enum Operation { + ADD, SUBTRACT, DIVIDE, MULTIPLY + } + + public double operateOnTwoNumbers(double numberOne, double numberTwo, Operation operation) { + if (numberOne > UPPER_LIMIT) { + throw new IllegalArgumentException("'numberOne' is too large"); + } + if (numberTwo > UPPER_LIMIT) { + throw new IllegalArgumentException("'numberTwo' is too large"); + } + double answer = 0; + + switch (operation) { + case ADD: + answer = numberOne + numberTwo; + break; + case SUBTRACT: + answer = numberOne - numberTwo; + break; + case DIVIDE: + answer = numberOne / numberTwo; + break; + case MULTIPLY: + answer = numberOne * numberTwo; + break; + } + + return answer; + } +} diff --git a/core-java-modules/core-java-lang-3/src/main/java/com/baeldung/constantspatterns/CalculatorConstants.java b/core-java-modules/core-java-lang-3/src/main/java/com/baeldung/constantspatterns/CalculatorConstants.java new file mode 100644 index 0000000000..2237782b00 --- /dev/null +++ b/core-java-modules/core-java-lang-3/src/main/java/com/baeldung/constantspatterns/CalculatorConstants.java @@ -0,0 +1,10 @@ +package com.baeldung.constantspatterns; + +public interface CalculatorConstants { + double PI = 3.14159265359; + double UPPER_LIMIT = 0x1.fffffffffffffP+1023; + + enum Operation { + ADD, SUBTRACT, MULTIPLY, DIVIDE + }; +} diff --git a/core-java-modules/core-java-lang-3/src/main/java/com/baeldung/constantspatterns/GeometryCalculator.java b/core-java-modules/core-java-lang-3/src/main/java/com/baeldung/constantspatterns/GeometryCalculator.java new file mode 100644 index 0000000000..47a0dc5233 --- /dev/null +++ b/core-java-modules/core-java-lang-3/src/main/java/com/baeldung/constantspatterns/GeometryCalculator.java @@ -0,0 +1,32 @@ +package com.baeldung.constantspatterns; + +public class GeometryCalculator implements CalculatorConstants { + public static final double UPPER_LIMIT = 100000000000000000000.0; + + public double operateOnTwoNumbers(double numberOne, double numberTwo, Operation operation) { + if (numberOne > UPPER_LIMIT) { + throw new IllegalArgumentException("'numberOne' is too large"); + } + if (numberTwo > UPPER_LIMIT) { + throw new IllegalArgumentException("'numberTwo' is too large"); + } + double answer = 0; + + switch (operation) { + case ADD: + answer = numberOne + numberTwo; + break; + case SUBTRACT: + answer = numberOne - numberTwo; + break; + case DIVIDE: + answer = numberOne / numberTwo; + break; + case MULTIPLY: + answer = numberOne * numberTwo; + break; + } + + return answer; + } +} diff --git a/core-java-modules/core-java-lang-3/src/main/java/com/baeldung/constantspatterns/calculations/MathConstants.java b/core-java-modules/core-java-lang-3/src/main/java/com/baeldung/constantspatterns/calculations/MathConstants.java new file mode 100644 index 0000000000..a7ecf7aabe --- /dev/null +++ b/core-java-modules/core-java-lang-3/src/main/java/com/baeldung/constantspatterns/calculations/MathConstants.java @@ -0,0 +1,16 @@ +package com.baeldung.constantspatterns.calculations; + +public final class MathConstants { + public static final double PI = 3.14159265359; + public static final double GOLDEN_RATIO = 1.6180; + public static final double GRAVITATIONAL_ACCELERATION = 9.8; + public static final double EULERS_NUMBER = 2.7182818284590452353602874713527; + + public enum Operation { + ADD, SUBTRACT, DIVIDE, MULTIPLY + } + + private MathConstants() { + + } +} diff --git a/core-java-modules/core-java-lang-3/src/test/java/com/baeldung/constantspatterns/ConstantPatternUnitTest.java b/core-java-modules/core-java-lang-3/src/test/java/com/baeldung/constantspatterns/ConstantPatternUnitTest.java new file mode 100644 index 0000000000..39cb8f82f9 --- /dev/null +++ b/core-java-modules/core-java-lang-3/src/test/java/com/baeldung/constantspatterns/ConstantPatternUnitTest.java @@ -0,0 +1,23 @@ +package com.baeldung.constantspatterns; + +import static org.junit.jupiter.api.Assertions.assertEquals; + +import org.junit.Test; + +public class ConstantPatternUnitTest { + @Test + public void givenTwoNumbersAndAdd_whenCallingCalculatorOperatOneTwoNumbers_correctAnswerReturned() { + Calculator calculator = new Calculator(); + double expected = 4; + double answer = calculator.operateOnTwoNumbers(2, 2, Calculator.Operation.ADD); + assertEquals(expected, answer); + } + + @Test + public void givenTwoNumbersAndAdd_whenCallingGeometryCalculatorOperatOneTwoNumbers_correctAnswerReturned() { + GeometryCalculator calculator = new GeometryCalculator(); + double expected = 4; + double answer = calculator.operateOnTwoNumbers(2, 2, GeometryCalculator.Operation.ADD); + assertEquals(expected, answer); + } +}