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Help writing a program using a switch statement

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  Help writing a program using a switch statement Abraar Ahmed <abraar93@gmail.com> - 2014-10-05 15:40 -0700
    Re: Help writing a program using a switch statement Knute Johnson <eternal@knutejohnson.com> - 2014-10-05 17:18 -0700
      Re: Help writing a program using a switch statement Arne Vajhøj <arne@vajhoej.dk> - 2014-10-10 22:02 -0400
        Re: Help writing a program using a switch statement Knute Johnson <eternal@knutejohnson.com> - 2014-10-10 20:27 -0700
          Re: Help writing a program using a switch statement Arne Vajhøj <arne@vajhoej.dk> - 2014-10-11 09:43 -0400
            Re: Help writing a program using a switch statement Knute Johnson <eternal@knutejohnson.com> - 2014-10-11 07:59 -0700
    Re: Help writing a program using a switch statement rossum <rossum48@coldmail.com> - 2014-10-06 09:38 +0100
    Re: Help writing a program using a switch statement Roedy Green <see_website@mindprod.com.invalid> - 2014-10-06 20:25 -0700
    Re: Help writing a program using a switch statement Henry Reardon <No_contact@example.com> - 2014-10-10 16:01 +0000

#30059 — Help writing a program using a switch statement

 Write a program using switch statement to allow users to choose an item of a menu. For example, the menu looks like the following.

File menu
1. Open
2. Close
3. Save
4. Exit
Enter your choice: 
If you type 1, then your program should print out "Open is selected" (double quotes not included). 

Notice:
(1) Using Scanner to get user choice;
(2) If the number user input is not in {1,2,3,4}, your program should let user know that. 

Here's what I have:

public static void main (String[]  args)  {

int user = 1

switch (1) {
case value: 1
System.out.println ("Open is selected");
break;
case value: 2
System.out.println ("Close is selected");
break;
case value: 3
System.out.println ("Save is selected")
break;
System.out.println ("Exit is selected")
default:
values_not_caught_above;

}

Can someone tell me if I'm headed in the right direction?

Any guidance would be much appreciated, thank you.

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#30060

On 10/5/2014 15:40, Abraar Ahmed wrote:
>   Write a program using switch statement to allow users to choose an item of a menu. For example, the menu looks like the following.
>
> File menu
> 1. Open
> 2. Close
> 3. Save
> 4. Exit
> Enter your choice:
> If you type 1, then your program should print out "Open is selected" (double quotes not included).
>
> Notice:
> (1) Using Scanner to get user choice;
> (2) If the number user input is not in {1,2,3,4}, your program should let user know that.
>
> Here's what I have:
>
> public static void main (String[]  args)  {
>
> int user = 1
>
> switch (1) {
> case value: 1
> System.out.println ("Open is selected");
> break;
> case value: 2
> System.out.println ("Close is selected");
> break;
> case value: 3
> System.out.println ("Save is selected")
> break;
> System.out.println ("Exit is selected")
> default:
> values_not_caught_above;
>
> }
>
> Can someone tell me if I'm headed in the right direction?
>
> Any guidance would be much appreciated, thank you.
>

Since this is homework, you need to look at the Java Language 
Specification, chapter 14.11 Switch Statement.  Everything you need to 
know is there.

http://docs.oracle.com/javase/specs/jls/se8/html/index.html

knute...

-- 

Knute Johnson

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#30073

On 10/5/2014 8:18 PM, Knute Johnson wrote:
> On 10/5/2014 15:40, Abraar Ahmed wrote:
>>   Write a program using switch statement to allow users to choose an
>> item of a menu. For example, the menu looks like the following.

>> switch (1) {
>> case value: 1
>> System.out.println ("Open is selected");
>> break;
>> case value: 2
>> System.out.println ("Close is selected");
>> break;
>> case value: 3
>> System.out.println ("Save is selected")
>> break;
>> System.out.println ("Exit is selected")
>> default:
>> values_not_caught_above;
>>
>> }

> Since this is homework, you need to look at the Java Language
> Specification, chapter 14.11 Switch Statement.  Everything you need to
> know is there.
>
> http://docs.oracle.com/javase/specs/jls/se8/html/index.html

JLS is good for many things, but learning basic Java syntax is not
one if them.

The Java tutorial would be a lot easier to learn from.

http://docs.oracle.com/javase/tutorial/java/index.html

http://docs.oracle.com/javase/tutorial/java/nutsandbolts/switch.html

Arne

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#30074

On 10/10/2014 19:02, Arne Vajhøj wrote:
> On 10/5/2014 8:18 PM, Knute Johnson wrote:
>> On 10/5/2014 15:40, Abraar Ahmed wrote:
>>>   Write a program using switch statement to allow users to choose an
>>> item of a menu. For example, the menu looks like the following.
>
>>> switch (1) {
>>> case value: 1
>>> System.out.println ("Open is selected");
>>> break;
>>> case value: 2
>>> System.out.println ("Close is selected");
>>> break;
>>> case value: 3
>>> System.out.println ("Save is selected")
>>> break;
>>> System.out.println ("Exit is selected")
>>> default:
>>> values_not_caught_above;
>>>
>>> }
>
>> Since this is homework, you need to look at the Java Language
>> Specification, chapter 14.11 Switch Statement.  Everything you need to
>> know is there.
>>
>> http://docs.oracle.com/javase/specs/jls/se8/html/index.html
>
> JLS is good for many things, but learning basic Java syntax is not
> one if them.
>
> The Java tutorial would be a lot easier to learn from.
>
> http://docs.oracle.com/javase/tutorial/java/index.html
>
> http://docs.oracle.com/javase/tutorial/java/nutsandbolts/switch.html
>
> Arne
>
>
>

There are some good examples in the JLS for the switch statement though. 
  That's why I told him to look there.

-- 

Knute Johnson

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#30075

On 10/10/2014 11:27 PM, Knute Johnson wrote:
> On 10/10/2014 19:02, Arne Vajhøj wrote:
>> On 10/5/2014 8:18 PM, Knute Johnson wrote:
>>> On 10/5/2014 15:40, Abraar Ahmed wrote:
>>>>   Write a program using switch statement to allow users to choose an
>>>> item of a menu. For example, the menu looks like the following.
>>
>>>> switch (1) {
>>>> case value: 1
>>>> System.out.println ("Open is selected");
>>>> break;
>>>> case value: 2
>>>> System.out.println ("Close is selected");
>>>> break;
>>>> case value: 3
>>>> System.out.println ("Save is selected")
>>>> break;
>>>> System.out.println ("Exit is selected")
>>>> default:
>>>> values_not_caught_above;
>>>>
>>>> }
>>
>>> Since this is homework, you need to look at the Java Language
>>> Specification, chapter 14.11 Switch Statement.  Everything you need to
>>> know is there.
>>>
>>> http://docs.oracle.com/javase/specs/jls/se8/html/index.html
>>
>> JLS is good for many things, but learning basic Java syntax is not
>> one if them.
>>
>> The Java tutorial would be a lot easier to learn from.
>>
>> http://docs.oracle.com/javase/tutorial/java/index.html
>>
>> http://docs.oracle.com/javase/tutorial/java/nutsandbolts/switch.html
>
> There are some good examples in the JLS for the switch statement though.

It has 3 examples:
* some code that works in C/C++ but does not work in Java
* some code showing fall through
* some normal code

Compare that to the tutorial that has 5 examples:
* some normal code
* some code showing how it would look like using if else if
* some code showing fall through
* some code showing multi labels
* some code showing switch on strings

Arne

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#30076

On 10/11/2014 06:43, Arne Vajhøj wrote:
> On 10/10/2014 11:27 PM, Knute Johnson wrote:
>> On 10/10/2014 19:02, Arne Vajhøj wrote:
>>> On 10/5/2014 8:18 PM, Knute Johnson wrote:
>>>> On 10/5/2014 15:40, Abraar Ahmed wrote:
>>>>>   Write a program using switch statement to allow users to choose an
>>>>> item of a menu. For example, the menu looks like the following.
>>>
>>>>> switch (1) {
>>>>> case value: 1
>>>>> System.out.println ("Open is selected");
>>>>> break;
>>>>> case value: 2
>>>>> System.out.println ("Close is selected");
>>>>> break;
>>>>> case value: 3
>>>>> System.out.println ("Save is selected")
>>>>> break;
>>>>> System.out.println ("Exit is selected")
>>>>> default:
>>>>> values_not_caught_above;
>>>>>
>>>>> }
>>>
>>>> Since this is homework, you need to look at the Java Language
>>>> Specification, chapter 14.11 Switch Statement.  Everything you need to
>>>> know is there.
>>>>
>>>> http://docs.oracle.com/javase/specs/jls/se8/html/index.html
>>>
>>> JLS is good for many things, but learning basic Java syntax is not
>>> one if them.
>>>
>>> The Java tutorial would be a lot easier to learn from.
>>>
>>> http://docs.oracle.com/javase/tutorial/java/index.html
>>>
>>> http://docs.oracle.com/javase/tutorial/java/nutsandbolts/switch.html
>>
>> There are some good examples in the JLS for the switch statement though.
>
> It has 3 examples:
> * some code that works in C/C++ but does not work in Java
> * some code showing fall through
> * some normal code
>
> Compare that to the tutorial that has 5 examples:
> * some normal code
> * some code showing how it would look like using if else if
> * some code showing fall through
> * some code showing multi labels
> * some code showing switch on strings
>
> Arne

OK I concede, you should have answered him not me.

-- 

Knute Johnson

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#30061

On Sun, 5 Oct 2014 15:40:47 -0700 (PDT), Abraar Ahmed
<abraar93@gmail.com> wrote:

> Write a program using switch statement to allow users to choose an item of a menu. For example, the menu looks like the following.
>
>File menu
>1. Open
>2. Close
>3. Save
>4. Exit
>Enter your choice: 
>If you type 1, then your program should print out "Open is selected" (double quotes not included). 
>
>Notice:
>(1) Using Scanner to get user choice;
>(2) If the number user input is not in {1,2,3,4}, your program should let user know that. 
>
>Here's what I have:
>
>public static void main (String[]  args)  {
>
>int user = 1
>
>switch (1) {
>case value: 1
>System.out.println ("Open is selected");
>break;
>case value: 2
>System.out.println ("Close is selected");
>break;
>case value: 3
>System.out.println ("Save is selected")
>break;
>System.out.println ("Exit is selected")
>default:
>values_not_caught_above;
>
>}
>
>Can someone tell me if I'm headed in the right direction?
>
>Any guidance would be much appreciated, thank you.
Read the question you are answering.  It says:

(1) Using Scanner to get user choice;

Your answer does not, so far, use Scanner.  That is one error.

As Knute has pointed out, there are errors in your use of the switch
statement.  To see one of them, run through your code on paper to see
what happens if the user selects '2'.  Be careful to follow exactly
what your code says, not what you meant it to say.  A great many bugs
live in the difference between the two.

rossum

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#30064

On Sun, 5 Oct 2014 15:40:47 -0700 (PDT), Abraar Ahmed
<abraar93@gmail.com> wrote, quoted or indirectly quoted someone who
said :

>case value: 1

there is no such keyword as value.

See http://mindprod.com/jgloss/switch.html
for an example.
-- 
Roedy Green Canadian Mind Products http://mindprod.com
There are only two industries that refer to their customers as users.
~ Edward Tufte (born: 1942 age: 72)

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#30068

Abraar Ahmed <abraar93@gmail.com> wrote in
news:8dcbb682-a1c4-4e43-b506-093de204ae87@googlegroups.com: 

>  Write a program using switch statement to allow users to choose an
>  item of a menu. For example, the menu looks like the following. 
> 
> File menu
> 1. Open
> 2. Close
> 3. Save
> 4. Exit
> Enter your choice: 
> If you type 1, then your program should print out "Open is selected"
> (double quotes not included). 
> 
> Notice:
> (1) Using Scanner to get user choice;
> (2) If the number user input is not in {1,2,3,4}, your program should
> let user know that. 
> 
> Here's what I have:
> 
> public static void main (String[]  args)  {
> 
> int user = 1
> 
> switch (1) {
> case value: 1
> System.out.println ("Open is selected");
> break;
> case value: 2
> System.out.println ("Close is selected");
> break;
> case value: 3
> System.out.println ("Save is selected")
> break;
> System.out.println ("Exit is selected")
> default:
> values_not_caught_above;
> 
> }
> 
> Can someone tell me if I'm headed in the right direction?
> 
> Any guidance would be much appreciated, thank you.

A better place to ask homework questions might be comp.lang.java.help. 
There is a lot of spam there these days but I *think* a few of the Java 
gurus still hang out there to help beginners with their questions. 

~~ 
Henry

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