Thread: Calculator Using AWT

My code is not working for some reason, help? When I try to compile, it says that there are 34 errors, many stating "illegal start of expression" and "';' expected"


import java.io.*;
import java.lang.Math.*;
import java.awt.*;
import java.awt.event.*;
import java.awt.Component.*;

public class Calculator extends Frame implements ActionListener, WindowListener

/* EQUAL
* POINT
* DECIMAL
* C
* MATH */

{

//1 Window
TextField Txwindow;

//29 Buttons
Button b1,b2,b3,b4,b5,b6,b7,b8,b9,b0; //10 Buttons on this Line
Button b10algo,blog,bealgo,bln; //4 Buttons on this Line
Button bpi,broot,bpower,be; //4 Buttons on this Line
Button bsin, bcos, btan, btrig; //4 Buttons on this Line
Button bclear,bpoint,bequal; //3 Buttons on this Line
Button badd,bsub,bmulti,bdivi; //4 Buttons on this Line

//5 Panels
Panel panelNorth,panelSouth,panelEast,panelWest,panelCen ter;

int x;

String aux1;
String aux2, lastCommand;
String value, calcDisplay;
int op, counter=0;

boolean point=false;

double n1,n2,n3,n4,preAns,secVal;
double answer=0,ans;

public static void main(String[] args) throws IOException
{
Calculator form=new Calculator(); //Creates a specified class
form.setSize(400,600); //Establishes Size of Window
form.setTitle ("CASIO FX-Superb007"); //This is the Title
form.setVisible(true); //The Window will Become Visible

}

public Calculator() throws IOException {

//Layout Head
setLayout(new BorderLayout(1,1));//Head, Beginning

//Panel
panelNorth= new Panel(new FlowLayout());
panelSouth= new Panel(new GridLayout(1,1));

panelEast= new Panel(new GridLayout(4,1));
panelWest= new Panel(new GridLayout(5,1));
panelCenter= new Panel(new GridLayout(6,3));

//North Finished
Txwindow= new TextField(50);
Txwindow.setEditable(false);
panelNorth.add(Txwindow);

//South Finished

bequal= new Button("="); //Equal Button
panelSouth.add(bequal);
//listener
bequal.addActionListener(this);

//West Finished

b10algo= new Button("10^x"); //10^algo
blog= new Button("+/-"); //Log
bealgo= new Button("e^x"); //E^algo
bln= new Button("Ln"); //Ln
be= new Button("e"); //e

panelWest.add(b10algo);
panelWest.add(blog);
panelWest.add(bealgo);
panelWest.add(bln);
panelWest.add(be);

//listener
b10algo.addActionListener(this);
blog.addActionListener(this);
bealgo.addActionListener(this);
bln.addActionListener(this);
be.addActionListener(this);

//East Finished

badd= new Button ("+"); //Addition
bsub= new Button("-"); //Subtraction
bmulti= new Button("*"); //Multiplication
bdivi= new Button("/"); //Division

panelEast.add(badd);
panelEast.add(bsub);
panelEast.add(bmulti);
panelEast.add(bdivi);

//listener
badd.addActionListener(this);
bsub.addActionListener(this);
bmulti.addActionListener(this);
bdivi.addActionListener(this);

//Center Finished

b1= new Button("1"); //Number 1
b2= new Button("2"); //Number 2
b3= new Button("3"); //Number 3
b4= new Button("4"); //Number 4
b5= new Button("5"); //Number 5
b6= new Button("6"); //Number 6
b7= new Button("7"); //Number 7
b8= new Button("8"); //Number 8
b9= new Button("9"); //Number 9
b0= new Button("0"); //Number 0



bpi= new Button("Pi");//pi
bpower= new Button("Power"); //Power
broot= new Button("Root"); //Root


bsin= new Button("Sin"); //sin
bcos= new Button("Cos"); //cos
btan= new Button("Tan"); //tan


bPoint= new Button("."); //Point
bclear= new Button("C"); //clear

panelCenter.add(bpi);
panelCenter.add(bpower);
panelCenter.add(broot);
panelCenter.add(bsin);
panelCenter.add(bcos);
panelCenter.add(btan);
panelCenter.add(b1);
panelCenter.add(b2);
panelCenter.add(b3);
panelCenter.add(b4);
panelCenter.add(b5);
panelCenter.add(b6);
panelCenter.add(b7);
panelCenter.add(b8);
panelCenter.add(b9);
panelCenter.add(bpoint);
panelCenter.add(b0);
panelCenter.add(bclear);

//listener
bpi.addActionListener(this);
bpower.addActionListener(this);
broot.addActionListener(this);
bsin.addActionListener(this);
bcos.addActionListener(this);
btan.addActionListener(this);
b1.addActionListener(this);
b2.addActionListener(this);
b3.addActionListener(this);
b4.addActionListener(this);
b5.addActionListener(this);
b6.addActionListener(this);
b7.addActionListener(this);
b8.addActionListener(this);
b9.addActionListener(this);
bpoint.addActionListener(this);
b0.addActionListener(this);
bclear.addActionListener(this);

panelCenter.repaint();


//Add to Panels, Border Layout

add(panelNorth, BorderLayout.NORTH);
add(panelSouth, BorderLayout.SOUTH);
add(panelEast, BorderLayout.EAST);
add(panelWest, BorderLayout.WEST);
add(panelCenter, BorderLayout.CENTER);


//This Adds a Listener to the Window
addWindowListener(this); }


public void repaint(Graphics g){

//The Color of this
g.setColor(Color.blue);
}

public void actionPerformed(ActionEvent e){

//input numbers

if(e.getSource() == b1){ aux1="1"; window=Txwindow.getText()+aux1; Txwindow.setText(value); }
if(e.getSource() == b2){ aux1="2"; window=Txwindow.getText()+aux1; Txwindow.setText(value); }
if(e.getSource() == b3){ aux1="3"; window=Txwindow.getText()+aux1; Txwindow.setText(value); }
if(e.getSource() == b4){ aux1="4"; window=Txwindow.getText()+aux1; Txwindow.setText(value); }
if(e.getSource() == b5){ aux1="5"; window=Txwindow.getText()+aux1; Txwindow.setText(value); }
if(e.getSource() == b6){ aux1="6"; window=Txwindow.getText()+aux1; Txwindow.setText(value); }
if(e.getSource() == b7){ aux1="7"; window=Txwindow.getText()+aux1; Txwindow.setText(value); }
if(e.getSource() == b8){ aux1="8"; window=Txwindow.getText()+aux1; Txwindow.setText(value); }
if(e.getSource() == b9){ aux1="9"; window=Txwindow.getText()+aux1; Txwindow.setText(value); }
if(e.getSource() == b0){ aux1="0"; window=Txwindow.getText()+aux1; Txwindow.setText(value); }
if(e.getSource() == bpoint&& point==false){ aux1="."; value=Txwindow.getText()+aux1; Txwindow.setText(value); point=true; }

//The Functions
if(e.getSource() == bpi){ Txwindow.setText(""+Math.PI); value=""; }
if(e.getSource() == be){ Txwindow.setText(""+Math.E); value=""; }

if(e.getSource() == bpower){
aux2=Txwindow.getText();
if(!aux2.equals("")){
preAns=Double.parseDouble(Txwindow.getText());
lastCommand="power";
Txwindow.setText("");}}

if(e.getSource() == broot){

aux2=Txwindow.getText();
if(!aux2.equals(""))
{n1=Double.parseDouble(Txwindow.getText());
Txwindow.setText(""+Math.sqrt(n1));
} }

if(e.getSource() == bsin){

aux2=Txwindow.getText();
if(!aux2.equals(""))
{n1=Double.parseDouble(Txwindow.getText());
Txwindow.setText(""+Math.sin(Math.toRadians(n1)));
}}

if(e.getSource() == bcos){

aux2=Txwindow.getText();
if(!aux2.equals(""))
{n1=Double.parseDouble(Txwindow.getText());
Txwindow.setText(""+Math.cos(Math.toRadians(n1)));
} }

if(e.getSource() == btan){

aux2=Txwindow.getText();
if(!aux2.equals(""))
{n1=Double.parseDouble(Txwindow.getText());
Txwindow.setText(""+Math.tan(Math.toRadians(n1)));
} }

if(e.getSource() == b10algo){

aux2=Txwindow.getText();
if(!aux2.equals(""))
{n1=Double.parseDouble(Txwindow.getText());
Txwindow.setText(""+Math.pow(10.0,n1));
} }

if(e.getSource() == blog){

aux2=Txwindow.getText();
if(!aux2.equals(""))
{n1=Double.parseDouble(Txwindow.getText());
n1=n1*(-1);
Txwindow.setText(""+n1);
} }

if(e.getSource() == bealgo){

aux2=Txwindow.getText();
if(!aux2.equals(""))
{n1=Double.parseDouble(Txwindow.getText());
Txwindow.setText(""+Math.pow(Math.E,n1));
} }

if(e.getSource() == bln){

aux2=Txwindow.getText();
if(!aux2.equals(""))
{n1=Double.parseDouble(Txwindow.getText());
Txwindow.setText(""+Math.log(n1));
} }

if(e.getSource() == badd){
aux2=Txwindow.getText();
if(!aux2.equals("")){
preRes=Double.parseDouble(Txwindow.getText());
lastCommand="+";
Txwindow.setText("");}

if(e.getSource() == broot){
aux2=Txwindow.getText();
if(!aux2.equals("")){
preRes=Double.parseDouble(Txwindow.getText());
lastCommand="-";
Txwindow.setText("");}
}

if(e.getSource() == bmulti){
aux2=Txwindow.getText();
if(!aux2.equals("")){
preRes=Double.parseDouble(Txwindow.getText());
lastCommand="*";
Txwindow.setText("");}}

if(e.getSource() == bdivi){
aux2=Txwindow.getText();
if(!aux2.equals("")){
preRes=Double.parseDouble(Txwindow.getText());
lastCommand="/";
Txwindow.setText("");}}

if(e.getSource() == bclear){ Txwindow.setText(""); }

if(e.getSource() == bequal){
Double secVal=Double.parseDouble(Txwindow.getText());

if(lastCommand.equals("+"))
ans=preAns+secVal;
else if(lastCommand.equals("-"))
ans=preAns-secVal;
else if(lastCommand.equals("*"))
ans=preAns*secVal;
else if (lastCommand.equals("/"))
ans=preAns/secVal;
else if (lastCommand.equals("power"));
ans=Math.pow(preAns,secVal);

Txwindow.setText(" "+ans);
lastCommand="=";

}}
public double calcoperations(int op, double aux2){
if(op==1)
{}
if(op==2)
{}
if(op==3)
{}
if(op==4)
{}
if(op==5)
{}
return ans; }

public void windowClosing(WindowEvent e){

System.exit(0);
}
public void windowActivated(WindowEvent e){
}
public void windowClosed(WindowEvent e){
}
public void windowDeactivated(WindowEvent e){
}
public void windowDeiconified(WindowEvent e){
}
public void windowIconified(WindowEvent e){
}
public void windowOpened(WindowEvent e){
}
}

Hi Sorry to tell you, but first start with basics of the java.
There are lot basic things missed in you code.

An "illegal start of expression" error is usually caused by either forgetting a closing bracket '}' or by forgetting to use a delimiter ';'

It can also be caused by nesting a method within another method

You forgot to post the full text of the error messages. We need them to be able to help you correct your code.

Originally Posted by hardikjadhav

Hi Sorry to tell you, but first start with basics of the java.
There are lot basic things missed in you code.

Ditto. If you can't figure out where to place brackets. Cut back to the basics.

I cannot figure out where I left a bracket out

Does your IDE editor have a matching {} finder? Put the cursor on a { or } and have the editor find the matching } or {.

One problem I see is that a lot of } follow statements.
Its best if they are on a line of their own and that they line up vertically with the code with the open {.
Also it helps if you put labels on them describing what block they are closing. For example:
class AClass {
...
} // end AClass <<<<<<<<<<<<<< NOTE