Add Interpreter

README.md

@@ -11,4 +11,5 @@ Project that implements some design patterns using Java 13.
 - Observer
 - Factory
 - Flyweight
-- Memento
+- Memento
+- Interpreter

src/interpreter/Annotation.txt

@@ -0,0 +1,21 @@
+###############################
+#         Interpreter         #
+###############################
+
+
+
+
+
+##### Language - EN
+
+- 
+
+
+##### Language - PT-BR
+
+- Tenho uma arvore, onde eu avalia os nós de baixo para cima, cada nó sabe "de avaliar". 
+Ex: A soma não é dois números, é duas expressões que podem ser qualquer coisa.
+
+- A ideia é ter uma arvore, e essa arvore se "alto" avaliar.
+
+- O padrão Interpreter é geralmente útil para interpretar DSLs (se você não sabe o que é uma DSL.

src/interpreter/Expression.java

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+package interpreter;
+
+public interface Expression {
+
+	double toEvaluate();
+
+}

src/interpreter/InterpreterMain.java

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+package interpreter;
+
+public class InterpreterMain {
+
+	public static void main(String[] args) {
+		System.out.println("--------------------------------------------- Begin Test Interpreter");
+
+
+		Expression exLeft1 = new Subtraction(new Number(2.5), new Number(10));// -7.5
+		Expression exRight1 = new Sum(new Number(5), new Number(10));//15
+
+		Expression sum1 = new Sum(exLeft1, exRight1);// (-7.5) + 15
+
+		System.out.println("Result Expression 1: " + sum1.toEvaluate());//7.5 ->> (2.5 - 10) + (5 + 10)
+
+
+		System.out.println("-------------------------");
+
+
+		Expression exLeft2 = new Multiplication(new Number(3), new Number(3));//9
+		Expression exRight2 = new Sum(new Number(0.5), new Number(0.5));//1
+
+		Expression sum2 = new Sum(exLeft2, exRight2);// 9 + 1
+
+		System.out.println("Result Expression 1: " + sum2.toEvaluate());//10 ->> (3 * 9) + (0.5 + 0.5)
+
+
+		System.out.println("--------------------------------------------- End Test Interpreter");
+	}
+
+}

src/interpreter/Multiplication.java

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+package interpreter;
+
+public class Multiplication implements Expression {
+
+	private Expression exLeft;
+	private Expression exRight;
+
+	public Multiplication(Expression exLeft, Expression exRight){
+		this.exLeft = exLeft;
+		this.exRight = exRight;
+	}
+
+	@Override
+	public double toEvaluate() {
+		double valueLeft = this.exLeft.toEvaluate();//evaluate yourself
+		double valueRight = this.exRight.toEvaluate();//evaluate yourself
+		return valueLeft * valueRight;
+	}
+
+}

src/interpreter/Number.java

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+package interpreter;
+
+public class Number implements Expression{
+
+	private double num;
+
+	public Number(double num){
+		this.num = num;
+	}
+
+	@Override
+	public double toEvaluate() {
+		return this.num;
+	}
+
+}

src/interpreter/Subtraction.java

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+package interpreter;
+
+public class Subtraction implements Expression {
+
+	private Expression exLeft;
+	private Expression exRight;
+
+	public Subtraction(Expression exLeft, Expression exRight){
+		this.exLeft = exLeft;
+		this.exRight = exRight;
+	}
+
+	@Override
+	public double toEvaluate() {
+		double valueLeft = this.exLeft.toEvaluate();//evaluate yourself
+		double valueRight = this.exRight.toEvaluate();//evaluate yourself
+		return valueLeft - valueRight;
+	}
+
+}

src/interpreter/Sum.java

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+package interpreter;
+
+public class Sum implements Expression{
+
+	private Expression exLeft;
+	private Expression exRight;
+
+	public Sum(Expression exLeft, Expression exRight){
+		this.exLeft = exLeft;
+		this.exRight = exRight;
+	}
+
+	@Override
+	public double toEvaluate() {
+		double valueLeft = this.exLeft.toEvaluate();//evaluate yourself
+		double valueRight = this.exRight.toEvaluate();//evaluate yourself
+		return valueLeft + valueRight;
+	}
+
+}