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[Java]Help my program plz

Right now I am writing a simple java program where a user inputs the radius of a circle and the program, in turn, calculates and displays the diameter, circumference, and area of the circle in a simple message box. nothing about this program is complicated, but this is my first real program and I am having a problem getting it to compile. I keep receiving this error...

Circle.java:7: ';' expected
^
1 error

I have reviewed my code thoroughly and can't find any instance where I am missing a semi-colon. here is my code, please.

// Java Programming Assignment 2.1
// Program to calculate circular circumference, diameter, and area

//Java Packages
import javax.swing.JOptionPane; // use JOptionPane

public class Circle {

// main method begins execution of Java application
public static void main( String args[] )
{
String firstNumber; // first string entered by user

int radius; // radius
int diameter; // radius * 2
int area; // Pi * radius^2
int circumference; // 2 * Pi * radius
int pi;

// read first number from user as a String
firstNumber = JOptionPane.showInputDialog( "Enter radius of a circle" );

// pi value constant
pi = 3.14159;

// convert radius from type String to typ int
radius = Integer.parseInt( firstNumber );

// calculate diameter
diameter = radius * 2;

// calculate area
area= pi * radius * radius;

// calculate circumference
circumference = 2 * pi * radius;

// display result
JOptionPane.showMessageDialog( null, "The Diameter is: " + diameter );

System.exit( 0 ); // terminate application with window

} // end method main

} // end class Circle

It is currently set up to calculate all three results, but only to display the diameter. Also, if you can, please explain how i can get my 3 results to display like this...

Diameter: -------
Circumference: -------
Area: -------

You're not missing a semi-colon, but the compiler does complain about a possible loss of precision when you use int instead of double for pi, radius, diameter and friends.

After making that change, I got a clean compile on JDK 1.6.0:

Code:

Parsing Input...

Compiling...

Standard Output from javac:

[search path for source files: [.]]

[search path for class files: [/usr/local/java/jdk1.6.0/jre/lib/resources.jar, /usr/local/java/jdk1.6.0/jre/lib/rt.jar, /usr/local/java/jdk1.6.0/jre/lib/sunrsasign.jar, /usr/local/java/jdk1.6.0/jre/lib/jsse.jar, /usr/local/java/jdk1.6.0/jre/lib/jce.jar, /usr/local/java/jdk1.6.0/jre/lib/charsets.jar, /usr/local/java/jdk1.6.0/jre/classes, /usr/local/java/jdk1.6.0/jre/lib/ext/dnsns.jar, /usr/local/java/jdk1.6.0/jre/lib/ext/sunpkcs11.jar, /usr/local/java/jdk1.6.0/jre/lib/ext/sunjce_provider.jar, /usr/local/java/jdk1.6.0/jre/lib/ext/localedata.jar, .]]

[parsing started /tmp/15602/Circle.java]

[parsing completed 145ms]

[loading /usr/local/java/jdk1.6.0/lib/ct.sym(META-INF/sym/rt.jar/javax/swing/JOptionPane.class)]

[loading /usr/local/java/jdk1.6.0/lib/ct.sym(META-INF/sym/rt.jar/java/lang/Object.class)]

[loading /usr/local/java/jdk1.6.0/lib/ct.sym(META-INF/sym/rt.jar/java/lang/String.class)]

[checking Circle]

[loading /usr/local/java/jdk1.6.0/lib/ct.sym(META-INF/sym/rt.jar/java/awt/Component.class)]

[loading /usr/local/java/jdk1.6.0/lib/ct.sym(META-INF/sym/rt.jar/javax/swing/JComponent.class)]

[loading /usr/local/java/jdk1.6.0/lib/ct.sym(META-INF/sym/rt.jar/java/awt/Container.class)]

[loading /usr/local/java/jdk1.6.0/lib/ct.sym(META-INF/sym/rt.jar/java/lang/Integer.class)]

[loading /usr/local/java/jdk1.6.0/lib/ct.sym(META-INF/sym/rt.jar/java/lang/Number.class)]

[loading /usr/local/java/jdk1.6.0/lib/ct.sym(META-INF/sym/rt.jar/java/lang/System.class)]

[loading /usr/local/java/jdk1.6.0/lib/ct.sym(META-INF/sym/rt.jar/java/lang/Error.class)]

[loading /usr/local/java/jdk1.6.0/lib/ct.sym(META-INF/sym/rt.jar/java/awt/HeadlessException.class)]

[loading /usr/local/java/jdk1.6.0/lib/ct.sym(META-INF/sym/rt.jar/java/lang/UnsupportedOperationException.class)]

[loading /usr/local/java/jdk1.6.0/lib/ct.sym(META-INF/sym/rt.jar/java/lang/RuntimeException.class)]

[loading /usr/local/java/jdk1.6.0/lib/ct.sym(META-INF/sym/rt.jar/java/lang/Exception.class)]

[loading /usr/local/java/jdk1.6.0/lib/ct.sym(META-INF/sym/rt.jar/java/lang/Throwable.class)]

[loading /usr/local/java/jdk1.6.0/lib/ct.sym(META-INF/sym/rt.jar/java/lang/NumberFormatException.class)]

[loading /usr/local/java/jdk1.6.0/lib/ct.sym(META-INF/sym/rt.jar/java/lang/IllegalArgumentException.class)]

[loading /usr/local/java/jdk1.6.0/lib/ct.sym(META-INF/sym/rt.jar/java/lang/StringBuilder.class)]

[loading /usr/local/java/jdk1.6.0/lib/ct.sym(META-INF/sym/rt.jar/java/lang/AbstractStringBuilder.class)]

[loading /usr/local/java/jdk1.6.0/lib/ct.sym(META-INF/sym/rt.jar/java/lang/CharSequence.class)]

[loading /usr/local/java/jdk1.6.0/lib/ct.sym(META-INF/sym/rt.jar/java/io/Serializable.class)]

[loading /usr/local/java/jdk1.6.0/lib/ct.sym(META-INF/sym/rt.jar/java/lang/Comparable.class)]

[loading /usr/local/java/jdk1.6.0/lib/ct.sym(META-INF/sym/rt.jar/java/lang/StringBuffer.class)]

[wrote /tmp/15602/Circle.class]

[total 1705ms]



Output File(s)

Circle.class

Okay I changed the variables to doubles and I got a clean compile too. Now what do I have to do in the "display" section to get all three results to appear in a left-alligned column?

Put your message in a JLabel and pass that to JOptionPane.showMessageDialog(), instead of passing the string.

Code:

// display result

JLabel message = new JLabel("The diameter is: " + diameter, JLabel.LEADING);

JOptionPane.showMessageDialog( null, message );

ok, thanks for the help. I appreciate it