implemented a first version of the functionplotter with swing

expressions.txt

-5
-x
-4+2
+1+(x^2)-(3*x)
+2*x+0.5*(x^2)-1
\ No newline at end of file
-3+(2^3)
-2*2*2+3
-(23+2*(2*3))-5
-1 + x*y^2 - (31 * x)-y
-1 + x^2 - (3 * x)
-2-x + 0.5*x^2 - 1
-(5*2-(5^2)+3*(201.01-15))
\ No newline at end of file

src/ASTPrinter.java

@@ -5,9 +5,19 @@ public class ASTPrinter implements  Visitor<String>{
         if(binaryOP.capsuled) {
             sb.append("(");
         }
-        sb.append(binaryOP.leftExpression.accept(this));
-        sb.append(binaryOP.operator);
-        sb.append(binaryOP.rightExpression.accept(this));
+        if(binaryOP.operator.contains("^")) {
+            sb.append("Pow(");
+            sb.append(binaryOP.leftExpression.accept(this));
+            sb.append(",");
+            sb.append(binaryOP.rightExpression.accept(this));
+            sb.append(")");
+        }
+        else {
+            sb.append(binaryOP.leftExpression.accept(this));
+            sb.append(binaryOP.operator);
+            sb.append(binaryOP.rightExpression.accept(this));
+        }
+
         if(binaryOP.capsuled) {
             sb.append(")");
         }

src/Application.java

 import java.io.BufferedReader;
 import java.io.FileReader;
 import java.io.IOException;
-import java.util.Arrays;
 import java.util.LinkedList;
 import java.util.List;
 
 public class Application {
     public static void main(String[] args) {
-        //LinkedList<String> expressions = new LinkedList<>()
-        //LinkedList<String> expressions = new List<>();
         List<String> expressions = new LinkedList<>();
         //Reads the file "expressions.txt" and adds its values to a list
         BufferedReader reader;
@@ -43,7 +40,9 @@ public class Application {
                 ASTPrinter printer = new ASTPrinter();
                 Evaluator evaluator = new Evaluator();
                 System.out.println("Printing: '" + printer.visit(exp) + "'");
+                String s = printer.visit(exp);
                 System.out.println("Evaluating: '" + evaluator.visit(exp) + "'");
+                SwingFunctionPlotter.plotFunction(s);
             }
             catch (ParserException e) {
                 System.out.println(e.getMessage());

src/Evaluator.java

@@ -3,7 +3,11 @@ public class Evaluator implements Visitor<Double>{
     @Override
     public Double visit(final Parser.BinaryOperation binaryOP) {
         double result = binaryOP.leftExpression.accept(this);
-        double rOperand = binaryOP.rightExpression.accept(this);
+        Double rOperand = binaryOP.rightExpression.accept(this);
+        if(rOperand==null) {
+
+
+        }
         switch (binaryOP.operator.charAt(0)) {
             case '+':
                 result += rOperand;

src/SwingFunctionPlotter.java

+import com.mindfusion.charting.FunctionSeries;
+import com.mindfusion.charting.swing.LineChart;
+
+import javax.swing.*;
+import java.awt.*;
+
+public class SwingFunctionPlotter extends JFrame {
+    private static final long serialVersionUID = 1L;
+
+    public static void plotFunction(String function) {
+        SwingUtilities.invokeLater(new Runnable() {
+            public void run() {
+                try {
+                    new SwingFunctionPlotter(function).setVisible(true);
+                }
+                catch(Exception e) {
+                    e.printStackTrace();
+                }
+            }
+        });
+    }
+
+    protected SwingFunctionPlotter(String function) {
+        setDefaultCloseOperation(EXIT_ON_CLOSE);
+        setSize(650, 400);
+        setTitle("Java Swing Library for Charts and Gauges: FunctionSeries");
+
+        getContentPane().add(initializeChart(function), BorderLayout.CENTER);
+    }
+
+    private LineChart initializeChart(String function) {
+        LineChart lineChart = new LineChart();
+        FunctionSeries series1;
+        try {
+            series1 = new FunctionSeries(function,1000, -20, 20);
+            series1.setTitle("Current function");
+            lineChart.getSeries().add(series1);
+        }
+        catch(Exception e) {
+            e.printStackTrace();
+        }
+        return lineChart;
+    }
+}
\ No newline at end of file