Swing Calculator - Logical errors

Question

Hello,
I have a couple of problems with the code below
one of them is with the setLayout().
Can anyone give a look to that code and tell me what's going wrong , or help me to make it work ??
Thanks in advance!
import java.awt.*;
import java.awt.BorderLayout;
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.Container;
import javax.swing.JButton;
import javax.swing.JCheckBox;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JTextArea;
import javax.swing.*;
public class Calculator extends JFrame implements ActionListener
    public static final int Width = 500;
    public static final int Height = 500;
    private JTextField Board;
    private JButton jbo0, jbo1, jbo2, jbo3, jbo4, jbo5, jbo6, jbo7, jbo8, jbo9,
                    jboAddition, jboSubtraction, jboMultiplication, jboDivision,
                    jboDot, jboLp, jboRp, jboClear, jboResult;
    public static void main(String args[])
    JFrame applet = new Calculator();
    JFrame frame = new JFrame();
    frame.add(frame);
    frame.setSize(Width,Height);
    frame.show();
public static void main(String args[])
    JFrame outputFrame = new Calculator();
//panel1.add(allyourstuff);
//panel1.add(moreofyourstuff);
    outputFrame.setVisible(true);
    public Calculator()
        Container outputPane = this.getContentPane();
        this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        this.setSize(Width, Height);
        outputPane.setLayout(new GridLayout (3, 3));
        Panel panel1 = new Panel();
        this.setDefaultCloseOperation( EXIT_ON_CLOSE );
        Board = new JTextField();
        panel1.add(Board);
        outputPane.add(panel1);
        //panel1.add(jbo0);
        //Numbers
        setLayout(new FlowLayout());
        setFont(new Font("Helvetica", Font.PLAIN, 8));
        JButton jbo0 = new JButton("0");
        jbo0.addActionListener(this);
        panel1.add(jbo0);
        jbo1 = new JButton("1");
        panel1.add(jbo1);
        jbo1.addActionListener(this);
        jbo2 = new JButton("2");
        panel1.add(jbo2);
        jbo2.addActionListener(this);
        jbo3 = new JButton("3");
        panel1.add(jbo3);
        jbo3.addActionListener(this);
        jbo4 = new JButton("4");
        panel1.add(jbo4);
        jbo4.addActionListener(this);
        jbo5 = new JButton("5");
        panel1.add(jbo5);
        jbo5.addActionListener(this);
        jbo6 = new JButton("6");
        panel1.add(jbo6);
        jbo6.addActionListener(this);
        jbo7 = new JButton("7");
        panel1.add(jbo7);
        jbo7.addActionListener(this);
        jbo8 = new JButton("8");
        panel1.add(jbo8);
        jbo8.addActionListener(this);
        jbo9 = new JButton("9");
        panel1.add(jbo9);
        jbo9.addActionListener(this);
        //Math Operations
        jboAddition = new JButton("+");
        panel1.add(jboAddition);
        jboAddition.addActionListener(this);
        jboSubtraction = new JButton("-");
        panel1.add(jboSubtraction);
        jboSubtraction.addActionListener(this);
        jboMultiplication = new JButton("*");
        panel1.add(jboMultiplication);
        jboMultiplication.addActionListener(this);
        jboDivision = new JButton("/");
        panel1.add(jboDivision);
        jboDivision.addActionListener(this);
        //Result etc..
        jboDot = new JButton(".");
        panel1.add(jboDot);
        jboDot.addActionListener(this);
        jboLp = new JButton("(");
        panel1.add(jboLp);
        jboLp.addActionListener(this);
        jboRp = new JButton(")");
        panel1.add(jboRp);
        jboRp.addActionListener(this);
        jboClear = new JButton("C");
        panel1.add(jboClear);
        jboClear.addActionListener(this);
        jboResult = new JButton("=");
        panel1.add(jboResult);
        jboResult.addActionListener(this);
    public void actionPerformed(ActionEvent e)
        if (e.getSource() instanceof JButton)
            JButton buClicked = (JButton) e.getSource();
            if (buClicked == jboClear)
                boardClear();
            else if(buClicked == jboResult)
                Calculate();
        else
            Calculate();
    public void UserInput(JButton buClicked)
        String input;
        input = Board.getText();
        if (buClicked == jbo0)
            Board.setText(input + "0");
        if (buClicked == jbo1)
            Board.setText(input + "1");
        if (buClicked == jbo2)
            Board.setText(input + "2");
        if (buClicked == jbo3)
            Board.setText(input + "3");
        if (buClicked == jbo4)
            Board.setText(input + "4");
        if (buClicked == jbo5)
            Board.setText(input + "5");
        if (buClicked == jbo6)
            Board.setText(input + "6");
        if (buClicked == jbo7)
            Board.setText(input + "7");
        if (buClicked == jbo8)
            Board.setText(input + "8");
        if (buClicked == jbo9)
            Board.setText(input + "9");
        if (buClicked == jboAddition)
            Board.setText(input + "+");
        if (buClicked == jboSubtraction)
            Board.setText(input + "-");
        if (buClicked == jboMultiplication)
            Board.setText(input + "*");
        if (buClicked == jboDivision)
            Board.setText(input + "/");
        if (buClicked == jboDot)
            Board.setText(input + ".");
        if (buClicked == jboLp)
            Board.setText(input + "(");
        if (buClicked == jboRp)
            Board.setText(input + ")");
     private void boardClear()
        Board.setText("");
    public void Calculate()
        int counter;
        int numParenthesis = 0;
        int lenInput;
        String calc;
        String Answer = "";
        char NumOther;
        calc = Board.getText();
        lenInput = calc.length();
        for (counter = 0; counter < lenInput; counter++)
            NumOther = calc.charAt(counter);
            if (NumOther == ')')
                numParenthesis--;
            if (NumOther == '(')
                numParenthesis++;
            if ((NumOther < '(') || (NumOther > '9') || (NumOther == '.'))
                Board.setText("Error");
            if (NumOther == '.' && (counter + 1 < calc.length()))
                for (int k = counter + 1; (k < calc.length()) && ((Character.isDigit(calc.charAt(k))) || ((calc.charAt(k))) == '.'); k++)
                    if (calc.charAt(k) == '.')
                        Board.setText("Error");
        if (numParenthesis != 0)
            Board.setText("Error");
        else
            Answer = Calculate2(calc);
            Board.setText(Answer);
    private String CalculatorImp(String oper1, String oper2, char Oper)
        Double op1, op2;
        double ops1, ops2;
        double ans = 0;
        String result;
        op1 = new Double (oper1);
        op2 = new Double (oper2);
        ops1 = op1.doubleValue();
        ops2 = op2.doubleValue();
        if (Oper == '+')
            ans = ops1 + ops2;
        if (Oper == '-')
            ans = ops1 - ops2;
        if (Oper == '*')
            ans = ops1 * ops2 ;
        if (Oper == '/')
            ans = ops1/ops2;
        result = Double.toString(ans);
        return result;
    private String Calculate2(String process)
        String answer = process;
        String op1 = "";
        String op2 = "";
        char userinput;
        int index = 0;
        int indexL = 0;
        int indexR = 0;
        int numInput = answer.length();
        int numPar = 0;
        int matchPar = 0;
        int indexOp1 = 0;
        int indexOp2 = 0;
        if (answer  != "Error")
            for (index = 0; index < numInput; index++)
                userinput = answer.charAt(index);
                if (userinput  == '(')
                    if (matchPar == 0)
                        indexOp1 = index;
                    matchPar++;
                    numPar++;
                if (userinput == ')')
                    matchPar--;
                    if (matchPar ==0)
                        indexOp2 = index;
            if (indexOp1 + 1 == indexOp2)
                Board.setText("Error");
            if (answer == "Error"  && numPar > 0)
                if (indexOp1 == 0)
                    if (indexOp2 == (numInput - 1))
                        if (indexOp1 != indexOp2)
                            answer = Calculate2(answer.substring(indexOp1 + 1, indexOp2));
                else if (indexOp1 == 0 && indexOp2 > 0)
                    if ((Character.isDigit(answer.charAt(indexOp2 + 1))))
                        Board.setText("Error");
                    else
                        answer = Calculate2(answer.substring(indexOp1 + 1, indexOp2)) + answer.substring(indexOp2 + 1);
                        numPar--;
                        while (numPar != 0)
                            answer = Calculate2(answer);
                            numPar--;
                else if ((indexOp1 > 0) && (indexOp2 > 0) && (indexOp2 != numInput - 1))
                    if (((Character.isDigit(answer.charAt(indexOp2 + 1 ))) ||  (Character.isDigit(answer.charAt(indexOp1 - 1 ))) ))
                        Board.setText("Error");
                    else
                        answer = answer.substring(0, indexOp1) + Calculate2(answer.substring(indexOp1 + 1, indexOp2)) + answer.substring(indexOp2 + 1);
                        numPar--;
                        while (numPar != 0)
                            answer = Calculate2(answer);
                            numPar--;
                else if (indexOp2 == numInput - 1 && indexOp1 > 0)
                    if (((Character.isDigit(answer.charAt(indexOp1 - 1)))))
                        Board.setText("Error");
                    else
                        answer = answer.substring(0, indexOp1) + Calculate2(answer.substring(indexOp1 + 1, indexOp2));
                        numPar--;
                        while (numPar != 0)
                            answer = Calculate2(answer);
                            numPar--;
            if (numPar == 0)
                if (answer != "Error")
                    if (!(Character.isDigit(answer.charAt(0))))
                        if (answer.charAt(0) != '-')
                            if (!(Character.isDigit(answer.charAt(answer.length() - 1))))
                                Board.setText("Error");
            for (index = 0; index < answer.length() && (answer == "Error"); index++)
                userinput = answer.charAt(index);
                if (userinput == '*' || userinput == '/')
                    if (!(Character.isDigit(answer.charAt(index-1))) || (!(Character.isDigit(answer.charAt(index + 1)))))
                        if (answer.charAt(index + 1) != '-')
                            Board.setText("Error");
                    if (answer.charAt(index + 1) == '-')
                        if (!(Character.isDigit(answer.charAt(index + 2))))
                            Board.setText("Error");
                    if (answer == "Error")
                        indexL = index - 1;
                        if (indexL > 2)
                            if ((answer.charAt(indexL - 1)) == '-')
                                if ((answer.charAt(indexL - 2)) == 'E')
                                    indexL = indexL -2;
                            while ((indexL  > 0) && ((Character.isDigit(answer.charAt(indexL - 2)) || ((answer.charAt(indexL - 1)) == '.') || ((answer.charAt(indexL - 1)) == 'E' ))))
                                indexL--;
                            if (indexL == 1)
                                if ((answer.charAt(indexL - 1)) == '-')
                                    indexL--;
                            if (indexL > 2)
                                if (((answer.charAt(indexL - 1)) == '-') && !(Character.isDigit(answer.charAt(indexL - 2))))
                                        indexL--;
                            op2 = answer.substring(index + 1, indexR + 1);
                for (index = 0; index < answer.length() && (answer != "Error"); index++)
                    if (index == 0)
                        index = 1;
                if (index > 0)
                        if (answer.charAt(index + 1) == '-')
                            index = index + 2;
                userinput = answer.charAt(index);
                if ((userinput == '+') || (userinput == '-'))
                    if (!(Character.isDigit(answer.charAt(index - 1))))
                        Board.setText("Error");
                    if (!(Character.isDigit(answer.charAt(index + 1))))
                        Board.setText("Error");
                    if ((answer.charAt(index+1) == '-') && (!(Character.isDigit(answer.charAt(index+2)))))
                         Board.setText("Error");
                    if (answer != "Error")
                        indexL = 0;
                        op1 = answer.substring(indexL , index);
                        indexR = index + 1;
                        while((indexR < answer.length()-1) && ((Character.isDigit(answer.charAt(indexR + 1))) || ((answer.charAt(indexR + 1)) == '.') || ((answer.charAt(indexR + 1)) == 'E')))
                            indexR++;
                            if (indexR < answer.length() - 2)
                                    if ((answer.charAt(indexR + 1)) == '-')
                                        indexR++;
                        op2 = answer.substring(index + 1, indexR + 1);
                        answer = CalculatorImp(op1, op2, userinput ) + answer.substring(indexR + 1);
                        index = 0;
        return answer;
}

Answer 1

Your UserInput method doesn't seem to get called anywhere.
You need to sort out the layout - try a vertical box containing the input and horizontal boxes for the button, or a simple grid. If using a GridLayout, the number of rows and column you give in the constructor should
Move the actual calculation code out into a separate class - you then can test it more easily with a driver which feeds it lots of expressions, and your UI code isn't all mixed up with it.
It's a convention to use lower case initial letters on variable and method names.
Your code is very redundant - create one ActionListener which you attach to each your single character button to append the value of that button to the input box, rather than having all those tests, and extract that code into a single method.
When you add a swing component to another, it keeps a reference to it so it can draw it. You don't need to, unless you want to do something else which it later on.
Eg:import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class SwingCalculator extends JFrame {
  public static void main(String args[]) {
    new SwingCalculator().setVisible(true);
  final JTextField board;
  public SwingCalculator () {
    Container outputPane = this.getContentPane();
    setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    setFont(new Font("Helvetica", Font.PLAIN, 18));
    setTitle("SwingCalculator");
    outputPane.setLayout(new BoxLayout(outputPane, BoxLayout.Y_AXIS));
    board = new JTextField();
    outputPane.add(board);
    final JPanel buttons = new JPanel();
    buttons.setLayout(new GridLayout (5, 4));
    outputPane.add(buttons);
    // Buttons which append to the board
    addButtons(buttons, "7", "8", "9", "+");
    addButtons(buttons, "4", "5", "6", "-");
    addButtons(buttons, "1", "2", "3", "*");
    addButtons(buttons, ".", "0", "E", "/");
    addButtons(buttons, "(", ")");
    // the C and = buttons have special action listeners
    final JButton cancel = new JButton("C");
    buttons.add(cancel);
    cancel.addActionListener(new ActionListener() {
      public void actionPerformed (ActionEvent event) {
        board.setText("");
    final JButton calculate = new JButton("=");
    buttons.add(calculate);
    // move the expression code to a separate class and call it here
    calculate.addActionListener(new ActionListener() {
      public void actionPerformed (ActionEvent event) {
        try {
          board.setText(ExpressionParser.evaluate(board.getText()));
        } catch (ExpressionParseException ex) {
          board.setText("ERROR");
    pack();
  // adds buttons which, when pressed, append their label to the board
  public void addButtons (JPanel panel, String... labels) {
    for (final String label:labels) {
      JButton button = new JButton(label);
      panel.add(button);
      button.addActionListener(new ActionListener() {
        public void actionPerformed(ActionEvent e) {
          board.setText(board.getText() + label);
}