BUG - Switch statement & compiler

I am overriding AccordionHeader. In the set Data method I
have a switch statement. I dont think the location of the statement
is relevant, but included for completeness. (MenuGroup is my own
class and not relevant)
If you have the following code Flex 3 \ FB 3 (both beta 3)
override public function set data(value:Object):void
var menuGroup:MenuGroup = value as MenuGroup;
// examine the groupType to determine if we need \ want to
change the style setting
// on this particular header
switch(menuGroup.groupType)
super.data = value;
The compiler will fail with an 'An internal build error has
occurred' error.
Put in a default case statement such as
case default:
break;
and all is well.
regards BOb

Thanks for reporting. You can track the bug here
https://bugs.adobe.com/jira/browse/ASC-3113
Thanks,
Gaurav Jain
Flex SDK Team

Similar Messages

Local class and switch statement -- compiler bug?

Does anybody know why the following does not compile with "LocalClass cannot be resolved to a type" error in the case 1: block
public class ProblemClass {
     public void localClassProblem() {
               class LocalClass {
                    void doNothing() {};
               int i = 0;
               switch (i) {
                    case 1: {
                         LocalClass instance1 = new LocalClass(); //ERROR: unresolved type
                                        break;
}while the following does (I only added case 2: where LocalClass type is not referenced within an embedded block)
public class ProblemClass {
     public void localClassProblem() {
               class LocalClass {
                    void doNothing() {};
               int i = 0;
               switch (i) {
                    case 1: {
                         LocalClass instance1 = new LocalClass();
                                        break;
                    case 2:
                         LocalClass instance2 = new LocalClass();
}Is it a compiler bug? Thanks for clarifying this.
--Michal

I'm using 1.5.0-b64
--Michal

Compiler error when useing switch statements in an inner class

I have defined several constants in a class and want to use this constans also in an inner class.
All the constants are defined as private static final int.
All works fine except when useing the switch statement in the inner class. I get the compiler error ""constant expression required". If I change the definition from private static final to protected static final it works, but why?
What's the difference?
Look at an example:
public class Switchtest
   private static final int AA = 0;
   protected static final int BB = 1;
   private static int i = 0;
   public Switchtest()
      i = 0; // <- OK
      switch(i)
         case AA: break; //<- OK, funny no problem
         case BB: break; //<- OK
         default: break;
private class InnerClass
      public InnerClass()
         i = 0; // <- OK: is accessible
         if (AA == i) // <- OK: AA is seen by the inner class; i is also accessible
            i = AA + 1;
         switch(i)
            case AA: break; // <- STRANGE?! Fail: Constant expression required
            case BB: break; // <- OK
            default: break;
}Thank's a lot for an explanation.

Just a though:
Maybe some subclass of Switchtest could decalare its own variable AA that is not final, but it can not declare its own BB because it is visible from the superclass. Therefore the compiler can not know for sure that AA is final.

Enum class not supported for switch() statement in 12.4 beta?

Hi fellow 12.4 beta testers,
It would appear "enum class" isn't supported for switch() statements in the 12.4 beta. This compiles fine under clang and g++. Will this be fixed for the final release? This currently causes compile errors for us, since __cplusplus >= 201103L evaluates to true, so our code uses "enum class" instead of plain "enum". It looks like the C++11 standard says it should be supported:
   Switching on enum class in C++ 0x - Stack Overflow
Many thanks,
Jonathan.
$ cat test.cpp
#include <iostream>
enum class Ternary { KnownFalse = 0, KnownTrue = 1, Unknown = 2 };
int main( void )
   Ternary foo;
   switch ( foo ) {
      case Ternary::KnownTrue:
      case Ternary::KnownFalse:
      case Ternary::Unknown:
         std::cout << "Success\n";
$ clang++ -std=c++11 test.cpp
$ g++ -std=c++11 test.cpp
$ /opt/SolarisStudio12.4-beta_mar14-solaris-x86/bin/CC -std=c++11 test.cpp
"test.cpp", line 8: Error: Cannot use Ternary to initialize integral type.
"test.cpp", line 8: Error: Switch selection expression must be of an integral type.
"test.cpp", line 9: Error: An integer constant expression is required for a case label.
"test.cpp", line 10: Error: An integer constant expression is required for a case label.
"test.cpp", line 11: Error: An integer constant expression is required for a case label.
5 Error(s) detected.

Thanks for reporting this problem! I have filed bug 18499900.
BTW, according to the C++11 standard, the code is actually not valid. Section 6.4.2, switch statement, says an implicit conversion to an integral type is required, which is not the case for for a scoped enum (one using the "class enum" syntax). This limitation was raised in the C++ Committee as an issue to be fixed, and the C++14 standard makes the code valid.
As a workaround, or to make the code conform to C++11, you can add casts to int for the enum variable and the enumerators.
Message was edited by: Steve_Clamage

Switch statement scope

Hi,
I've got a little question about the switch()-case statement.
let's consider the statement:
1: switch( nr){
2: case 1:
3: Vector vect = new Vector();
4: break;
5: case 2:
6: Vector vect = new Vector();
7: break;
8: }
At compile time, the compiler complains about line 6, he says the vect is allready defined.
But, when you take for example the if statement:
if ( bool)
Vector vect;
else
Vector vect;
he won't complain (dunno if java uses lazy evaluation).
of course one of the arguments for giving the error is that if you don't put the break, the switch will loop. but a for() loop does the same thing, yet there you can define the Vector inside the body (allthough it's not nice design).
besides that since switch is actually a nested if-statement, then it should be able to compile the above switch statement.
so, what are the real reasons it's not possible???
Tom

let's consider the statement:
1: switch( nr){
2: case 1:
3: Vector vect = new Vector();
4: break;
5: case 2:
6: Vector vect = new Vector();
7: break;
8: }
At compile time, the compiler complains about line 6,
he says the vect is allready defined.
But, when you take for example the if statement:
if ( bool)
Vector vect;
else
Vector vect;
he won't complain (dunno if java uses lazy
evaluation).It should complain! If you can compile the example if statement above, then I'd suggest your compiler has a bug in it.
of course one of the arguments for giving the error is
that if you don't put the break, the switch will loop.The argument for giving the error is that the scope of any variable declaration is its smallest enclosing block (delimited by braces).
but a for() loop does the same thing, yet there you
can define the Vector inside the body (allthough it's
not nice design).1. Only if the body is a block.
2. It is good design to keep your variable scope small.
besides that since switch is actually a nested
if-statement, Is it?
then it should be able to compile the
above switch statement.
so, what are the real reasons it's not possible???See above - If you put braces around the body of each case statement, you will be able to do what you are trying to do.

Use of boolean variables in BPEL switch statements

I have a workflow with a single boolean input parameter:
<element name="input" type="boolean"/>
I wish to use a switch statement within the workflow, based on the value of that boolean parameter.
When I use the following XPath expression:
bpws:getVariableData("input","payload","/tns:BooleanRequest/tns:input")
I get the correct functionality, although I get the following BPEL compiler warning:
" [bpelc] [Warning ORABPEL-10078]: return value of this expression may not be a boolean
[bpelc] [Description]: in line 35 of "C:\eclipse\workspace\Boolean\Boolean.bpel", xpath expression "bpws:getVariableData("input","payload","/tns:BooleanRequest/tns:input")" used in <switch> may not return boolean type value, the xpath engine would automatically try to convert the return value to boolean..
[bpelc] [Potential fix]: Please use one of the built-in boolean functions from xpath http://www.w3.org/TR/xpath#section-Boolean-Functions to convert the return value to boolean.."
However, the boolean functions referenced do not appear to be relevant to a variable which is already of a boolean type. If I attempt to use the boolean() function in my XPath expression, I get rid of the compiler error, but the workflow now does not work as required.
How can I get rid of the compiler warning and still get the required functionality, and/or am I doing the wrong thing?
I am currently running on JBoss, with BPEL release 2.1.2 [build #1226].
Thanks for any help or ideas.

Hi Marlon,
Thanks for that - I guess we have to accept the vagaries of XPath and the absence of type-checking for variables.
I hadn't fully understood until I started investigating that I can assign ANY string to variable of type xsd:boolean, which has been the cause of some of the confusion for me - whether that value is then considered true or false depends on how you write your test condition.
I tried with your condition, and it didn't seem to work (evaluated to true if the variable data was the string "true()", but otherwise it seemed to always evaluate to false.
I also tried the following:
condition="bpws:getVariableData('booleanVariable')=true()"
but that evaluates to true for any string of length > 0.
The only one I can get to consistently work is:
condition="bpws:getVariableData('booleanVariable')=string(true())"
although that means that variable data of "TRUE" will evaluate to false (may well be the correct behaviour, depending on how you're setting the boolean variable in the first place).

Switch Statement again

I am new to Java and am trying to learn how to use and understand the nuances involved in using the Switch statment.
Yesterday, I received tremendous help, As a result, I am closer to understanding the switch statement and how it works.
My program is designed to use 5 different input boxes. These represent a total for quizzes, homework assignments, 2 midterms, and a final exam.
These are casted to double; then, they are added together and divided by five to obtain an average (the student's GPA). The GPA is then going to assigned a grade depending up the range in the If then statement.
I intend on using a message box to inform the user of the GPA and another followed by another message box to show them their grade.
I would like to incorporate the switch statement (so I can learn how to use it) to show them their grade.
I know the code needs tweaking but this is what I have so far:
import javax.swing.JOptionPane;
public class Switchgrade{
//declaration of class
public static void main(String args[])
//declaration of main
String midone; String midtwo; String quiz; String homework; //declares variables to hold the grades, quiz and homework scores
String last;
double one; //first midterm
double two; //second midterm
double three;double four; double five; //final, quiz and homework scores
double average; //GPA
char a; char b; char c; char d; char f;char grade;
midone = JOptionPane.showInputDialog("Please enter the first midterm"); //first score to add
one = Double.parseDouble(midone);
midtwo = JOptionPane.showInputDialog("please enter second midterm"); //second midterm to add
two = Double.parseDouble(midtwo);
last = JOptionPane.showInputDialog("please enter final exam score");//final exam score to add
three = Double.parseDouble(last);
quiz = JOptionPane.showInputDialog("please enter quiz score");//quiz score to add
four = Double.parseDouble(quiz);
homework= JOptionPane.showInputDialog("please enter homework score");//homework score to add
five = Double.parseDouble(homework);
average = (one + two+ three + four + five)/5; //average of all five scores
if(average >= 90)
grade = 'a';
else
if(average >= 80 )
grade = 'b';
switch (grade)
case a:
JOptionPane.showMessageDialog(null,"The total of all your scores is " + b+"\nYour final grade is an A");
break;
default:
JOptionPane.showMessageDialog(null,"Sorry, you received a grade of " + b + ". \nYou failed.");
break;
System.exit(0);
}//end of main
}//end of class
As you can see, I am only using two grades, just so I can learn to use it. However, when I go to compile this, I get this error message:
constant expression required: case a:, with the ^ under the a.
What does this error message me and how do I fix this.
Thanks in advance for your help.

case a:is trying to use a variable with the name "a" for the comparison. This is illegal in java
what you want is
case 'a':this will do a comparison against the char value 'a'

Using a Switch statement for Infix to Prefix Expressions

I am stuck on the numeric and operator portion of the switch statement...I have the problem also figured out in an if/else if statement and it works fine, but the requirements were for the following algorithm:
while not end of expression
switch next token of expression
case space:
case left parenthesis:
skip it
case numeric:
push the string onto the stack of operands
case operator:
push the operator onto the stack of operators
case right parenthesis:
pop two operands from operand stack
pop one operator from operator stack
form a string onto operand stack
push the string onto operand stack
pop the final result off the operand stack
I know that typically case/switch statement's can only be done via char and int's. As I said I am stuck and hoping to get some pointers. This is for a homework assignment but I am really hoping for a few pointers. I am using a linked stack class as that was also the requirements. Here is the code that I have:
   import java.io.*;
   import java.util.*;
   import java.lang.*;
/*--------------------------- PUBLIC CLASS INFIXTOPREFIX --------------------------------------*/
/*-------------------------- INFIX TO PREFIX EXPRESSIONS --------------------------------------*/
    public class infixToPrefix {
      private static LinkedStack operators = new LinkedStack();
      private static LinkedStack operands = new LinkedStack();
        // Class variable for keyboard input
      private static BufferedReader stdin = new BufferedReader(new InputStreamReader(System.in));
         // Repeatedly reads in infix expressions and evaluates them
       public static void main(String[] args) throws IOException {
      // variables
         String expression, response = "y";
      // obtain input of infix expression from user
         while (response.charAt(0) == 'y') {
            System.out.println("Enter a parenthesized infix expression.");          // prompt the user
            System.out.println("Example: ( ( 13 + 2 ) * ( 10 + ( 8 / 3 ) ) )");
            System.out.print("Or as: ((13+2)*(10+(8/3))): ");
            expression = stdin.readLine();     // read input from the user
         // output prefix expression and ask user if they would like to continue
            System.out.println("The Prefix expression is: " + prefix(expression));     // output expression
            System.out.println("Evaluate another? y or n: ");          // check with user for anymore expressions
            response = stdin.readLine();     // read input from user
            if (response.charAt(0) == 'n') {          // is user chooses n, output the statement
               System.out.println("Thank you and have a great day!");
            }     // end if statement
         }     // end while statement
      }     // end method main
   /*------------- CONVERSION OF AN INFIX EXPRESSION TO A PREFIX EXPRESSION ------------*/
   /*--------------------------- USING A SWITCH STATEMENT ------------------------------*/
       private static String prefix(String expression) {
            // variables
         String symbol, operandA, operandB, operator, stringA, outcome;
           // initialize tokenizer
         StringTokenizer tokenizer = new StringTokenizer(expression, " +-*/() ", true);
         while (tokenizer.hasMoreTokens()) {
            symbol = tokenizer.nextToken();     // initialize symbol
            switch (expression) {
               case ' ':
                  break;     // accounting for spaces
               case '(':
                  break;     // skipping the left parenthesis
               case (Character.isDigit(symbol.charAt(0))):      // case numeric
                  operands.push(symbol);                                   // push the string onto the stack of operands
                  break;
               case (!symbol.equals(" ") && !symbol.equals("(")):     // case operator
                  operators.push(symbol);                                             // push the operator onto the stack of operators
                  break;
               case ')':
                  operandA = (String)operands.pop();     // pop off first operand
                  operandB = (String)operands.pop();     // pop off second operand
                  operator = (String)operators.pop();     // pop off operator
                  stringA = operator + " " + operandB + " " + operandA;          // form the new string
                  operands.push(stringA);
                  break;
            }     // end switch statement
         }     // end while statement
         outcome = (String)operands.pop();     // pop off the outcome
         return outcome;     // return outcome
      }     // end method prefix
   }     // end class infixToPrefixAny help would be greatly appreciated!

so, i did what flounder suggested:
         char e = expression.charAt(0);
         while (tokenizer.hasMoreTokens()) {
            symbol = tokenizer.nextToken();     // initialize symbol
            switch (e) {
               case ' ':
                  break;     // accounting for spaces
               case '(':
                  break;     // skipping the left parenthesis
               case '0':
               case '1':
               case '2':
               case '3':
               case '4':
               case '5':
               case '6':
               case '7':
               case '8':
               case '9':
                  operands.push(symbol);     // push the string onto the stack of operands
                  break;                               // case numeric
               case '+':
               case '-':
               case '*':
               case '/':
                  operators.push(symbol);     // push the operator onto the stack of operators
                  break;                               // case operator
               case ')':
                  operandA = (String)operands.pop();     // pop off first operand
                  operandB = (String)operands.pop();     // pop off second operand
                  operator = (String)operators.pop();     // pop off operator
                  stringA = operator + " " + operandB + " " + operandA;          // form the new string
                  operands.push(stringA);
                  break;
               default:
            }     // end switch statement
         }     // end while statement
         outcome = (String)operands.pop();     // pop off the outcome
         return outcome;     // return outcomeafter this, I am able to compile the code free of errors and I am able to enter the infix expression, however, the moment enter is hit it provides the following errors:
Exception in thread "main" java.lang.NullPointerException
     at LinkedStack$Node.access$100(LinkedStack.java:11)
     at LinkedStack.pop(LinkedStack.java:44)
     at infixToPrefix.prefix(infixToPrefix.java:119)
     at infixToPrefix.main(infixToPrefix.java:59)
Any ideas as to why? I am still looking through seeing if I can't figure it out, but any suggestions? Here is the linked stack code:
    public class LinkedStack {
   /*--------------- LINKED LIST NODE ---------------*/
       private class Node {
         private Object data;
         private Node previous;
      }     // end class node
   /*-------------- VARIABLES --------------*/
      private Node top;
/*-- Push Method: pushes object onto LinkedStack --*/
       public void push(Object data) {
         Node newTop = new Node();
         newTop.data = data;
         newTop.previous = top;
         top = newTop;
      }     // end function push
   /*--- Pop Method: pop obejct off of LinkedStack ---*/
       public Object pop()      {
         Object data = top.data;
         top = top.previous;
         return data;
      }     // end function pop
   } // end class linked stackEdited by: drmsndrgns on Mar 12, 2008 8:10 AM
Edited by: drmsndrgns on Mar 12, 2008 8:14 AM
Edited by: drmsndrgns on Mar 12, 2008 8:26 AM

Methods & Switch Statement in java.. HELP!!

hi all...
i am having a slight problem as i am constructing a method --> menu() which handles displaying
menu options on the screen, prompting the user to select A, B, C, D, S or Q... and then returns the user
input to the main method!!!
i am having issues with switch statement which processes the return from menu() methd,,,
could you please help?!!
here is my code...
import java.text.*;
import java.io.*;
public class StudentDriver
   public static void main(String[] args) throws IOException
      for(;;)
         /* Switch statement for menu manipulation */
         switch(menu())
               case A: System.out.println("You have selected option A");
                              break;
               case B: System.out.println("You have selected option B");
                              break;
               case C: System.out.println("You have selected option C");
                              break;
               case D: System.out.println("You have selected option D");
                              break;
               case S: System.out.println("You have selected option S");
                              break;
               case Q: System.out.println("\n\n\n\n\n\n\t\t Thank you for using our system..." +
                                                                "\n\n\t\t\t Good Bye \n\n\n\n");
                              exit(0);
   static char menu()
      char option;
      BufferedReader stdin = new BufferedReader(new InputStreamReader(System.in));
      System.out.println("\n\n");
      System.out.println("\n\t\t_________________________");
      System.out.println("\t\t|                       |");
      System.out.println("\t\t| Student Manager Menu |");
      System.out.println("\t\t|_______________________|");
      System.out.println("\n\t________________________________________");
      System.out.println("\t| \t\t\t\t\t|");
      System.out.println("\t| Add new student\t\t A \t|");
      System.out.println("\t| Add credits\t\t\t B \t|");
      System.out.println("\t| Display one record\t\t C \t|");
      System.out.println("\t| Show the average credits\t D \t|");
      System.out.println("\t| \t\t\t\t\t|");
      System.out.println("\t| Save the changes\t\t S \t|");
      System.out.println("\t| Quit\t\t\t\t Q \t|");
      System.out.println("\t|_______________________________________|\n");
      System.out.print("\t Your Choice: ");
      option = stdin.readLine();
         return option;
}Thanking your help in advance...
yours...
khalid

Hi,
There are few changes which u need to make for making ur code work.
1) In main method, in switch case change case A: to case 'A':
Characters should be represented in single quotes.
2) in case 'Q' change exit(0) to System.exit(0);
3) The method static char menu() { should be changed to static char menu() throws IOException   {
4) Change option = stdin.readLine(); to
option = (char)stdin.read();
Then compile and run ur code. This will work.
Or else just copy the below code
import java.text.*;
import java.io.*;
public class StudentDriver{
     public static void main(String[] args) throws IOException {
          for(;;) {
               /* Switch statement for menu manipulation */
               switch(menu()) {
                    case 'A': System.out.println("You have selected option A");
                    break;
                    case 'B': System.out.println("You have selected option B");
                    break;
                    case 'C': System.out.println("You have selected option C");
                    break;
                    case 'D': System.out.println("You have selected option D");
                    break;
                    case 'S': System.out.println("You have selected option S");
                    break;
                    case 'Q':
                    System.out.println("\n\n\n\n\n\n\t\t Thank you for using our system..." +
                    "\n\n\t\t\t Good Bye \n\n\n\n");
                    System.exit(0);
     static char menu() throws IOException {
          char option;
          BufferedReader stdin = new BufferedReader(new InputStreamReader(System.in));
          System.out.println("\n\n");
          System.out.println("\n\t\t_________________________");
          System.out.println("\t\t| |");
          System.out.println("\t\t| Student Manager Menu |");
          System.out.println("\t\t|_______________________|");
          System.out.println("\n\t________________________________________");
          System.out.println("\t| \t\t\t\t\t|");
          System.out.println("\t| Add new student\t\t A \t|");
          System.out.println("\t| Add credits\t\t\t B \t|");
          System.out.println("\t| Display one record\t\t C \t|");
          System.out.println("\t| Show the average credits\t D \t|");
          System.out.println("\t| \t\t\t\t\t|");
          System.out.println("\t| Save the changes\t\t S \t|");
          System.out.println("\t| Quit\t\t\t\t Q \t|");
          System.out.println("\t|_______________________________________|\n");
          System.out.print("\t Your Choice: ");
          option = (char)stdin.read();
          return option;
regards
Karthik

Switch statement for AS3 - Flash CS3

Hey guys, I currently have a code of a switch statement for as1- as2.
This is it:
switch (int(Math.random() * 20))
    case 0:
        hint = "The total amount of confusion in this world remains constant. It just gets shifted around.";
        break;
    case 1:
        hint = "If you experience poor performance, adjust the quality settings in your preference menu option.";
        break;
    case 2:
        hint = "Anticipation of death is better than death itself.";
        break;
    case 3:
        hint = "At the core of all well-founded belief lies belief that is unfounded.";
        break;
    case 4:
        hint = "The problem with instant gratification is that it takes too long.";
        break;
    case 5:
        hint = "Never let your schooling interfere with your education.";
        break;
    case 6:
        hint = "Beware of geeks bearing gifs.";
        break;
    case 7:
        hint = "Collaboration is essential: It allows you to blame someone else.";
        break;
    case 8:
        hint = "Read my MIPs - no new VAXes.";
        break;
    case 9:
        hint = "Where is the sea, said the fish, as they swam through it.";
        break;
    case 10:
        hint = "You can safely blame any bugs on Aoedipus, who is too busy grinding battlegrounds to do QA on her own work.";
        break;
    case 11:
        hint = "Anything worth doing is worth overdoing.";
        break;
    case 12:
        hint = "There is more to life than increasing its speed.";
        break;
    case 13:
        hint = "Don\'t worry, this will take about as long as the time it takes to play a 2v2 match with 4 ret pallies.";
        break;
    case 14:
        hint = "There is nothing worse than the brilliant image of a fuzzy concept.";
        break;
    case 15:
        hint = "If you are not part of the solution, you are part of the precipitate.";
        break;
    case 16:
        hint = "Two wrongs don\'t make a right, but three lefts do.";
        break;
    case 17:
        hint = "The heresy of today is the logic of tomorrow.";
        break;
    case 18:
        hint = "It\'s not that life is so short, it\'s just that you\'re dead a really long time.";
        break;
    case 19:
        hint = "Those who love sausage, the law, and holy canon should never watch any of them being made.";
        break;
    case 20:
        hint = "What if there were no hypothetical questions?";
        break;
} // End of switch
hint = "HINT: " + hint;
This code is for a dynamic tet with the var 'hint' (No ' ' )
But in as3 there is no var and I am having trouble converting it to AS3 coding, can someone show me the correct conversion of the code to make it work with AS3. I will make the instance name 'hint'.
Thank you ahead of time.

In addition to what other guys said, if you still want to use switch it should be:
switch (Math.round(Math.random() * 20)) - this will cover all the possible integers.
Nevertheless, I believe using switch in this case is not as efficient and scalable as using, say, array.
1. array index access is faster than switch.
2. if you need to make additions, you will need to make additions in switch while with array you just need to add/subtract member
3. if you will need to switch to a more dynamic model (say, getting hints from xml) - it will not be possible with switch
4. you may need a greater degree of randmization (Math.random is not as random as one may think) in which case resorting/reordering array is much simpler and faster.
So, I suggest you switch to the following code:
var hints:Array = [];
hints[0] = "Anticipation of death is better than death itself.";
hints[1] = "Anything worth doing is worth overdoing.";
hints[2] = "At the core of all well-founded belief lies belief that is unfounded.";
hints[3] = "Beware of geeks bearing gifs.";
hints[4] = "Collaboration is essential: It allows you to blame someone else.";
hints[5] = "Don\'t worry, this will take about as long as the time it takes to play a 2v2 match with 4 ret pallies.";
hints[6] = "If you are not part of the solution, you are part of the precipitate.";
hints[7] = "If you experience poor performance, adjust the quality settings in your preference menu option.";
hints[8] = "It\'s not that life is so short, it\'s just that you\'re dead a really long time.";
hints[9] = "Never let your schooling interfere with your education.";
hints[10] = "Read my MIPs - no new VAXes.";
hints[11] = "The heresy of today is the logic of tomorrow.";
hints[12] = "The problem with instant gratification is that it takes too long.";
hints[13] = "The total amount of confusion in this world remains constant. It just gets shifted around.";
hints[14] = "There is more to life than increasing its speed.";
hints[15] = "There is nothing worse than the brilliant image of a fuzzy concept.";
hints[16] = "Those who love sausage, the law, and holy canon should never watch any of them being made.";
hints[17] = "Two wrongs don\'t make a right, but three lefts do.";
hints[18] = "What if there were no hypothetical questions?";
hints[19] = "Where is the sea, said the fish, as they swam through it.";
hints[20] = "You can safely blame any bugs on Aoedipus, who is too busy grinding battlegrounds to do QA on her own work.";
hint = hints[int(Math.random() * hints.length)];
// OR
hint = hints[Math.round(Math.random() * (hints.length - 1))];

Switch Statement not initializing value

I'm taking a basic JAVA class and one of our assignments is to use the switch statement to determine the price of a product the add up the total of all products entered at the end. The code below won't compile because it says that "price" isn't initialized. If I initialize the variable as "0.0" then when the program finishes it is still "0.0" which means the switch section isn't working. Can anyone tell me why this isn't working?
import java.util.Scanner;
public class Product
public static void main( String args[] )
     Scanner input = new Scanner(System.in);
     int product;
     int quantity;
     double price;
     double total = 0.0;
     System.out.print("Enter product number: ");
     product = input.nextInt();
     while (product != -1)
          System.out.print("Enter quantity: ");
          quantity = input.nextInt();
          switch (product)
               case 5:
                    price = 6.87;
                    break;
               case 4:
                    price = 4.49;
                    break;
               case 3:
                    price = 9.98;
                    break;
               case 2:
                    price = 4.50;
                    break;
               case 1:
                    price = 2.98;
                    break;
               default:
                    System.out.print("Invalid product number");
                    break;
          total = total + price;
          System.out.println("Enter product number: (-1 to quit)");
          product = input.nextInt();
     System.out.printf("Total retail value of product is: $%.2f", price);
Thanks for any help!
Nathan

I think the correct code should be:
import java.util.Scanner;
public class Product
public static void main( String args[] )
     Scanner input = new Scanner(System.in);
     int product;
     int quantity;
     double price = 0.0;
     double total = 0.0;
     System.out.print("Enter product number: ");
     product = input.nextInt();
     while (product != -1)
          System.out.print("Enter quantity: ");
          quantity = input.nextInt();
          switch (product)
               case 5:
                    price = 6.87;
                    break;
               case 4:
                    price = 4.49;
                    break;
               case 3:
                    price = 9.98;
                    break;
               case 2:
                    price = 4.50;
                    break;
               case 1:
                    price = 2.98;
                    break;
               default:
                    System.out.print("Invalid product number");
                    break;
          total = total + (price*quantity);
          System.out.println("Enter product number: (-1 to quit)");
          product = input.nextInt();
     System.out.printf("Total retail value of product is: $%.2f", total);
}

Switch statement problem

I am doing a question in which I have to make a simple ATM program that can withraw and deposit money as many times as the user wants. To exit the program the user has to hit "x". I have to use a switch statement. Im getting incompatible type errors after compiling it. Can anyone help me? Sorry if the formattings not too good.
//ATM.java
//This program reads in a user's opening balance and performs a withdrawal or a deposit at the request of the user
import java.text.*;
     public class ATM
     public static void main(String args[])
          int      balance;
          char      withdrawal, deposit, choice;
          //Ask for the opening balance
          System.out.print("Please enter your opening balance");
          balance=UserInput.getInt();
          //Find out what the user wants done
          System.out.print("What would you like to do? (Withdrawal, Depositor Exit(x))");
          choice=UserInput.getChar();
                                                                      switch(choice){
case "w":
                                                                      while(balance>0)
                                                                                          System.out.print("How much would you like to withdraw?");
                                                                                          withdrawal=UserInput.getChar();
                                                                                          balance=balance-withdrawal;
                                                                                          System.out.print("Your remaining balance is " + balance);
                                                                                          break;
case "d":
while(balance>0)
                                                                                          System.out.print("How much do you wish to deposit?");
                                                                                          deposit=UserInput.getChar();
                                                                                          balance=balance+deposit;
                                                                                          System.out.print("Your new balance is " + balance);
                                                                                          break;
case "x":
                                                            System.out.print("Goodbye and thank you for using this program");
                                                                                          break;
default:
                                                                 System.out.print("We were not able to process your request, please try again");
                                                                                          break;
}

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Original Message:
Switch statement problem
Xivilai Registered: Mar 3, 2007 9:52 AM      Mar 3, 2007 10:06 AM
I am doing a question in which I have to make a simple ATM program that can withraw and deposit money as many times as the user wants. To exit the program the user has to hit "x". I have to use a switch statement. Im getting incompatible type errors after compiling it. Can anyone help me? Sorry if the formattings not too good.
//ATM.java
//This program reads in a user's opening balance and performs a withdrawal or a deposit at the request of the user
import java.text.*;
public class ATM
public static void main(String args[])
int balance;
char withdrawal, deposit, choice;
//Ask for the opening balance
System.out.print("Please enter your opening balance");
balance=UserInput.getInt();
//Find out what the user wants done
System.out.print("What would you like to do? (Withdrawal, Depositor Exit(x))");
choice=UserInput.getChar();
switch(choice){
case 'w':
while(balance>0)
System.out.print("How much would you like to withdraw?");
withdrawal=UserInput.getChar();
balance=balance-withdrawal;
System.out.print("Your remaining balance is " + balance);
break;
case 'd':
while(balance>0)
System.out.print("How much do you wish to deposit?");
deposit=UserInput.getChar();
balance=balance+deposit;
System.out.print("Your new balance is " + balance);
break;
case 'x':
System.out.print("Goodbye and thank you for using this program");
break;
default:
System.out.print("We were not able to process your request, please try again");
break;
}

Help with switch statement

Hello I have a copy of my code below. Everything compiles fine its just when the code gets to the switch statement I get an error saying
Exception in thread "main" java.util.InputMismatchException
at java.util.Scanner.throwFor(Scanner.java:819)
at java.util.Scanner.next(Scanner.java:1431)
at java.util.Scanner.nextInt(Scanner.java:2040)
at java.util.Scanner.nextInt(Scanner.java:2000)
at Sample.main(Sample.java:55)
Something is not working right when the user enters an integer expression. what can I do to fix this?
import java.util.*;
import java.io.*;
// Declare a public class
public class Sample {
     public static void main (String[] args){
     //Declare Variables
     float float0, float1;
     int int0, int1;
     String mathSign;
     char charMathSign;
     Scanner sc = new Scanner(System.in);
     //Ask user to Enter FLoating-Point Number Expression
     System.out.println("Enter a simple floating-point expression: ");
     float0 = sc.nextFloat();
     mathSign = sc.next ();
     float1 = sc.nextFloat();
     if(mathSign.equals("+"))
     System.out.println(float0 + " + " + float1 + " = " + (float0 + float1));
     else if(mathSign.equals("-"))
     System.out.println(float0 + " - " + float1 + " = " + (float0 - float1));
     else if(mathSign.equals("*"))
     System.out.println(float0 + " * " + float1 + " = " + (float0 * float1));
     else if(mathSign.equals("/"))
     System.out.println(float0 + " / " + float1 + " = " + (float0 / float1));
     //Ask the user to enter a simple floating point expression
     System.out.println("Enter a simple integer expression: ");
     int0 = sc.nextInt ();
     charMathSign = mathSign.charAt(0);
     int1 = sc.nextInt ();
     switch (charMathSign)
          case '+': System.out.println(int0 + " + " + int1 + " = " + (int0 + int1));
          break;
          case '-': System.out.println(int0 + " - " + int1 + " = " + (int0 - int1));
          break;
          case '*': System.out.println(int0 + " * " + int1 + " = " + (int0 * int1));
          break;
          case '/': System.out.println(int0 + " / " + int1 + " = " + (int0 / int1));
          break;
[/code]

{color:#000080}Duplicate posting, please post all responses at{color}{color:#0000ff}
http://forum.java.sun.com/thread.jspa?threadID=5219239{color}{color:#000080}
db{color}

Switch statement to java string

Hello!
I am programing a form in jsp that will send an e-mail to different people , depending on the selection of a SELECT box.
I am using a Bean which will take the option chosen in the select and then prepare the message.
My problem is that the option list has a lot of values and I would like to use the switch statement , but I always receive a compilation error since the switch statement only allows int and I am using a String....
Should I use a nested if in that case...or there is another solution?
================
Form.html
Region <SELECT NAME="region">
<OPTION VALUE="SouthEastEurope">South East Europe</OPTION>
<OPTION VALUE="Italy">Italy</OPTION>
<OPTION VALUE="SouthernAfrica">Southern Africa</OPTION>
<OPTION VALUE="France">France</OPTION>
<OPTION VALUE="NorthernAfrica">Northern Africa</OPTION>
<OPTION VALUE="MiddleEast">Middle East</OPTION>
<OPTION VALUE="Iberia">Iberia</OPTION>
</SELECT><P>....
==============================
SendMail.java
switch(region)
                    case SouthEastEurope:
                         toAddress = "[email protected]";
                         break;
                    case Italy:
                         toAddress = "[email protected]";
                         break;
........and so on.....
               }

How about generating a Map to match the country to an address.
Map mymap = new HashMap();
mymap.put("SouthEastEurope", "[email protected]");
mymap.put("Italy", "[email protected]");
String toadress = (String) mymap.get(region);Saves you from a horrible switch statement.

Problem with switch-statement & ä, ö, ü

Hi all,
I am doing this Java online tutorial right now and have a problem with one of the exercises. Hopefully you can help me:
I have to write a program that determines the number of consonants, vowels, punctuation characters, and spaces in an input line. I found a solution, but have two questions about it:
     Im unable to calculate the amount of umlauts (ä, ö, ü). Somehow the program doesnt recognize those characters. Why?
     In general Im not very happy with this huge list of cases. How would you solve a problem like this? Is there a more convenient/elegant way?
Thanks in advance!
Write a program that determines the number of consonants, vowels, punctuation characters, and spaces in an input line.
Read in the line into a String (in the usual way). Now use the charAt() method in a loop to access the characters one by one.
Use a switch statement to increment the appropriate variables based on the current character. After processing the line, print out
the results.
import java.util.Scanner;
class Kap43A1
public static void main ( String[] args )
    String line;
    char letter;
    int total, countV=0, countC=0, countS=0, countU=0, countP=0;
    Scanner scan = new Scanner(System.in);
    System.out.println( "Please write a sentence " );
    line = scan.nextLine();
    total=line.length(); //Gesamtanzahl an Zeichen des Satzes
    for (int counter=0; counter<total; counter++)
      letter = line.charAt(counter); //ermitteln des Buchstabens an einer bestimmten Position des Satzes
      switch (letter)
        case 'A': case 'a':
        case 'E': case 'e':
        case 'I': case 'i':
        case 'O': case 'o':
        case 'U': case 'u':
          countV++;
          break;
        case 'B': case 'b': case 'C': case 'c': case 'D': case 'd': case 'F': case 'f': case 'G': case 'g': case 'H': case 'h':
        case 'J': case 'j': case 'K': case 'k': case 'L': case 'l': case 'M': case 'm': case 'N': case 'n': case 'P': case 'p':
        case 'Q': case 'q': case 'R': case 'r': case 'S': case 's': case 'T': case 't': case 'V': case 'v': case 'W': case 'w':
        case 'X': case 'x': case 'Y': case 'y': case 'Z': case 'z':
          countC++;
          break;
        case ' ':
          countS++;
          break;
        case ',': case '.': case ':': case '!': case '?':
          countP++;
          break;
        case 'Ä': case 'ä': case 'Ö': case 'ö': case 'Ü': case 'ü':
          countU++;
          break;
    System.out.println( "Total amount of characters:\t" + total );
    System.out.println( "Number of consonants:\t\t" + countC );
    System.out.println( "Number of vocals:\t\t" + countV );
    System.out.println( "Number of umlauts:\t\t" + countU );
    System.out.println( "Number of spaces:\t\t" + countS );
    System.out.println( "Number of punctuation chars:\t" + countP );
}

WRE wrote:
In general Im not very happy with this huge list of cases. How would you solve a problem like this? Is there a more convenient/elegant way?I've been doing this a lot lately myself evaluating documents with 20 or so million words. Few tips:
1. Regular expressions can vastly reduce the list of cases. For example you can capture all letters from a to z or A to Z as follows [a-zA-Z]. To match a single character in a String you can then make use of the Pattern and Matcher classes, and incorporate the regular expression. e.g.
//Un-compiled code, may contain errors.
private Pattern letterPattern = Pattern.compile("[a-zA-Z]");
public int countNumberOfLettersInString(final String string) {
    int count = 0;
    Matcher letterMatcher = letterPattern.matcher(string);
    while(letterMatcher.find()) {
      count++;
    return count;
}2. As mentioned above, Sets are an excellent choice. Simply declare a static variable and instantiate it using a static initializer block. Then loop over the String to determine if the character is in the given set. e.g.
//Un-compiled code, may contain errors.
private static Set<Character> macrons = new HashSet<Character>();
static {
    macrons.add('ä');
    macrons.add('ö');
    macrons.add('ü');
public int countNumberOfMacronsInString(final String string) {
    int count = 0;
    for(char c : string.toCharArray()) {
      if(macrons.contains(c) {
        count++;
    return count;
}Mel

BUG - Switch statement & compiler

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