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7 Replies Latest reply: Feb 3, 2008 5:14 PM by DrClap RSS

1 error -each class has 0 errors when run as separate file

807601 Newbie
Currently Being Moderated
This application compiled the first time I ran it. and restarted it. I opened the application and got 11 errors. I removed the "import
java.util.Scanner; // program uses class Scanner" statement from the "Comparison" and "Division" sections and I'm still getting "1" error as indicated here:

// Calculation Project
// Addition, Multiplication, Difference And Division.java
/* Calculation program that displays the sum, product,
difference and quotient of two numbers */
// Created: Clarence Winfrey on January 31, 2008

import java.util.Scanner; // program uses class Scanner

public class Addition
{
// main method begins execution of Java application
public static void main( String args[] )
{
// create Scanner to obtain input from command window
Scanner input = new Scanner( System.in );

int number1; // first number to add
int number2; // second number to add
int sum; // sum of number1 and number2

System.out.print( "Enter first integer: " ); // prompt
number1 = input.nextInt(); // read first number from user

System.out.print( "Enter second integer: " ); // prompt
number2 = input.nextInt(); // read second number from user

sum = number1 + number2; // add numbers

System.out.printf( "Sum is %d\n", sum ); // display sum

} // end method main

} // end class Addition

// Calculate the product of three integers.



public class Product
{
public static void main( String args[] )
{
// create Scanner to obtain input from command window
Scanner input = new Scanner( System.in );

int x; // first number input by user
int y; // second number input by user
int z; // third number input by user
int result; // product of numbers

System.out.print( "Enter first integer: " ); // prompt for input
x = input.nextInt(); // read first integer

System.out.print( "Enter second integer: " ); // prompt for input
y = input.nextInt(); // read second integer

System.out.print( "Enter third integer: " ); // prompt for input
z = input.nextInt(); // read third integer

result = x * y * z; // calculate product of numbers

System.out.printf( "Product is %d\n", result );

} // end method main

} // end class Product

// Compare integers using if statements, relational operators
// and equality operators.


public class Comparison
{
// main method begins execution of Java application
public static void main( String args[] )
{
// create Scanner to obtain input from command window
Scanner input = new Scanner( System.in );

int number1; // first number to compare
int number2; // second number to compare

System.out.print( "Enter first integer: " ); // prompt
number1 = input.nextInt(); // read first number from user

System.out.print( "Enter second integer: " ); // prompt
number2 = input.nextInt(); // read second number from user

if ( number1 == number2 )
System.out.printf( "%d == %d\n", number1, number2 );

if ( number1 != number2 )
System.out.printf( "%d != %d\n", number1, number2 );

if ( number1 < number2 )
System.out.printf( "%d < %d\n", number1, number2 );

if ( number1 > number2 )
System.out.printf( "%d > %d\n", number1, number2 );

if ( number1 <= number2 )
System.out.printf( "%d <= %d\n", number1, number2 );

if ( number1 >= number2 )
System.out.printf( "%d >= %d\n", number1, number2 );

} // end method main

} // end class Comparison

// Calculate the quotient of two integers.


import java.util.Scanner; // program uses class Scanner

public class Division
{
// main method begins execution of Java application
public static void main( String args[] )
{
// create Scanner to obtain input from command window
Scanner input = new Scanner( System.in );

int x; // first number input by user
int y; // second number input by user

int result; // quotient of numbers

System.out.print( "Enter first integer: " ); // prompt for input
x = input.nextInt(); // read first integer

System.out.print( "Enter second integer: " ); // prompt for input
y = input.nextInt(); // read second integer

result = x / y ; // calculate quotient of numbers

System.out.printf( "Quotient is %d\n", result );

} // end method main

} // end class Division

**Build Output:**Configuration: Calculation Project - JDK version 1.6.0 <Default> - <Default>------------------
E:\JAVA\Calculation Project\Calculation.java:114: class, interface, or enum expected
import java.util.Scanner; // program uses class Scanner
^
1 error

Process completed.
  • 1. Re: 1 error -each class has 0 errors when run as separate file
    800282 Newbie
    Currently Being Moderated
    Are all classes in separate files?
    class Addition in Addition.java
    class Product in Product.java
    etc.
  • 2. Re: 1 error -each class has 0 errors when run as separate file
    807601 Newbie
    Currently Being Moderated
    Classes are in separate files when they run correctly but as indicated in the post. they are in the same file when I get the error and interestingly I get onlty one error that is apparantly occuring at the end of the addition section or beginning of the multiplication section. There seem to be no problems with the Comparison or Division classes. as indicated here
    // Calculation Project
    // Addition, Multiplication, Difference And Division.java
    /* Calculation program that displays the sum, product, 
       difference and quotient of two numbers */
    // Created: Clarence Winfrey on January 31, 2008
    
    import java.util.Scanner; // program uses class Scanner
    
    public class Addition 
    {
       // main method begins execution of Java application
       public static void main( String args[] )
       {
          // create Scanner to obtain input from command window
          Scanner input = new Scanner( System.in );
    
          int number1; // first number to add
          int number2; // second number to add
          int sum; // sum of number1 and number2
    
          System.out.print( "Enter first integer: " ); // prompt 
          number1 = input.nextInt(); // read first number from user
    
          System.out.print( "Enter second integer: " ); // prompt 
          number2 = input.nextInt(); // read second number from user
    
          sum = number1 + number2; // add numbers
    
          System.out.printf( "Sum is %d\n", sum ); // display sum
    
       } // end method main
    
    } // end class Addition
    
    // Calculate the product of three integers.
    
    
    
    public class Product 
    {
       public static void main( String args[] )
       {
          // create Scanner to obtain input from command window
          Scanner input = new Scanner( System.in );
    
          int x; // first number input by user
          int y; // second number input by user
          int z; // third number input by user
          int result; // product of numbers
    
          System.out.print( "Enter first integer: " ); // prompt for input
          x = input.nextInt(); // read first integer
    
          System.out.print( "Enter second integer: " ); // prompt for input
          y = input.nextInt(); // read second integer
          
          System.out.print( "Enter third integer: " ); // prompt for input
          z = input.nextInt(); // read third integer
    
          result = x * y * z; // calculate product of numbers
    
          System.out.printf( "Product is %d\n", result );
    
       } // end method main
    
    } // end class Product
    
    // Compare integers using if statements, relational operators 
    // and equality operators.
    
    
    public class Comparison 
    {
       // main method begins execution of Java application
       public static void main( String args[] )
       {
          // create Scanner to obtain input from command window
          Scanner input = new Scanner( System.in );
    
          int number1; // first number to compare
          int number2; // second number to compare
    
          System.out.print( "Enter first integer: " ); // prompt 
          number1 = input.nextInt(); // read first number from user 
    
          System.out.print( "Enter second integer: " ); // prompt 
          number2 = input.nextInt(); // read second number from user 
          
          if ( number1 == number2 ) 
             System.out.printf( "%d == %d\n", number1, number2 );
    
          if ( number1 != number2 )
             System.out.printf( "%d != %d\n", number1, number2 );
    
          if ( number1 < number2 )
             System.out.printf( "%d < %d\n", number1, number2 );
    
          if ( number1 > number2 )
             System.out.printf( "%d > %d\n", number1, number2 );
    
          if ( number1 <= number2 )
             System.out.printf( "%d <= %d\n", number1, number2 );
    
          if ( number1 >= number2 )
             System.out.printf( "%d >= %d\n", number1, number2 );
     
       } // end method main
    
    } // end class Comparison 
    
     // Calculate the quotient of two integers.
     
     
     import java.util.Scanner; // program uses class Scanner
         
     public class Division 
    {
       // main method begins execution of Java application
       public static void main( String args[] )
       {
          // create Scanner to obtain input from command window
          Scanner input = new Scanner( System.in );
    
          int x; // first number input by user
          int y; // second number input by user
         
          int result; // quotient of numbers
          
          System.out.print( "Enter first integer: " ); // prompt for input
          x = input.nextInt(); // read first integer
    
          System.out.print( "Enter second integer: " ); // prompt for input
          y = input.nextInt(); // read second integer
    
          result = x / y ; // calculate quotient of numbers
          
          System.out.printf( "Quotient is %d\n", result );
          
           } // end method main
    
    } // end class Division
  • 3. Re: 1 error -each class has 0 errors when run as separate file
    800282 Newbie
    Currently Being Moderated
    tenec wrote:
    Classes are in separate files when they run correctly but as indicated in the post. they are in the same file when I get the error and interestingly I get onlty one error that is apparantly occuring at the end of the addition section or beginning of the multiplication section. There seem to be no problems with the Comparison or Division classes. as indicated here
    What seems to be the problem then? Just don't stuff more than one class in one source file.
  • 4. Re: 1 error -each class has 0 errors when run as separate file
    807601 Newbie
    Currently Being Moderated
    sorry if I seem slow--- but after trying your suggestion I got this error when I tried to compile:

    "E:\JAVA\Product Comparison Division.java:114: class, interface, or enum expected
    import java.util.Scanner; // program uses class Scanner"

    Any thoughts or suggestions??
  • 5. Re: 1 error -each class has 0 errors when run as separate file
    807601 Newbie
    Currently Being Moderated
    It's not a complicated rule:

    You can't put more than a single public, top-level class into a .java-File.

    The standard says that each public top-level class needs to be in a .java file with a file name that corresponds to the class name (without the package).

    So the class foo.Bar needs to be defined in a file called "Bar.java" (placed in a directory called "foo")
    and the class foo.Quux needs to be defined in a file called "Quux.java" (placed in a directory called "foo").

    Now that rule effectively makes it impossible to put foo.Bar and foo.Quux into the same .java file (as long as they are public top-level classes).

    Why do you want to put them into the same file?
  • 6. Re: 1 error -each class has 0 errors when run as separate file
    807601 Newbie
    Currently Being Moderated
    I took your advice and made some progress. I now have some other errors:

    E:\JAVA\Calculation Project\src\Calculation Project.java:7: '{' expected
    public class Calculation Project {
    ^
    E:\JAVA\Calculation Project\src\Calculation Project.java:11: ';' expected
    Calculation ProjectFrame frame = new Calculation ProjectFrame();
    ^
    E:\JAVA\Calculation Project\src\Calculation Project.java:11: '(' or '[' expected
    Calculation ProjectFrame frame = new Calculation ProjectFrame();
    ^
    E:\JAVA\Calculation Project\src\Calculation ProjectFrame.java:10: '{' expected
    public class Calculation ProjectFrame extends Frame {
    ^
    E:\JAVA\Calculation Project\src\Calculation ProjectFrame.java:29: ';' expected
    Calculation ProjectFrame.this.windowClosed();
    ^
    E:\JAVA\Calculation Project\src\Calculation ProjectFrame.java:45: ';' expected
    Calculation ProjectFrame.this.windowClosed();
    ^
    6 errors
    // Calculation Project
    // Addition, Multiplication, Difference And Division.java
    /* Calculation program that displays the sum, product, 
       difference and quotient of two numbers */
    // Created: Clarence Winfrey on January 31, 2008
    
    import java.util.Scanner; // program uses class Scanner
    
    public class Addition 
    
    {
       // main method begins execution of Java application
       public static void main( String args[] )
       {
          // create Scanner to obtain input from command window
          Scanner input = new Scanner( System.in );
    
          int number1; // first number to add
          int number2; // second number to add
          int sum; // sum of number1 and number2
    
          System.out.print( "Enter first integer: " ); // prompt 
          number1 = input.nextInt(); // read first number from user
    
          System.out.print( "Enter second integer: " ); // prompt 
          number2 = input.nextInt(); // read second number from user
    
          sum = number1 + number2; // add numbers
    
          System.out.printf( "Sum is %d\n", sum ); // display sum
    
       } // end method main
    
    } // end class Addition
    I'm not sure what the error messages mean.
  • 7. Re: 1 error -each class has 0 errors when run as separate file
    DrClap Expert
    Currently Being Moderated
    If you look closely, you will see that the code in those error messages is nowhere to be seen in the code that you posted. So your first step would be to find the right code to look at.