5A

Write an application called IfPractice. It will have a main method. There is no starter coder.

In the main method: do the following:

• In then draft, ask the user for his/her first and last name using this prompt: System.out.print("Enter your first and last name: ");
• In the final, I made a mistake and so you need to use this prompt System.out.print("Enter your full name: "); Updated Sept 25
  
• Print Hello, name! where name is the name that was entered.
• Get just the first name.
• Print: I think I will call you nickname where nickname is the nickname in the table below.
  

  First Name	Nickname
  James or james	Jim
  Robert or robert	Bobby
  Ashwani or ashwani	Ash
  Any other name	Buddy

• Prompt the user for his/her age. Prompt with System.out.print("How old are you? ");
• Get the age
• Based on the age, print one of the messages in the table followed by a comma, a space, and the nickname.
  Example: You are a child, Jim
  

  This age and over	Under	Message
  0	18	You are a child
  18	21	You can vote, but you can not drink
  21	65	You are a full adult
  65		You can get Social Security

• Print Goodbye, name! where name is the original name that was entered.

Hint: To get just the first name, you need the index of the space. You can get that with the String method indexOf. indexOf returns the index of the first occurrence of the substring or -1 if the substring is not found.

Use this code to get the index of the space

int indexOfSpace = name.indexOf(" ");

If the indexOfSpace is > -1, use substring to get all characters in the first name. Otherwise use the whole name entered as the first name

Notes:

• Use the proper if structure.
• No not use do nothing if or else clauses
• Do not do unnecessary tests in the if clause
  For example this is incorrect:
  if (age >= 18 && age < 21)
  Leave out the age >= 18. It HAS to be true because you have just determined that age < 18 is false.

For the draft, do the first 2 steps.

5A draft:
5A final: (link updated Sept 19)

5B

We do not want users of our classes to be able to set invalid values for instance variables. Now that you know how to use if statements, you are going to add error checking to a a few classes from earlier homeworks. You can copy correct solutions from Canvas Modules if you need to..

You should not print error messages from constructors or methods of object. In the real world, you might throw an exception when the parameter is invalid, but we have not covered exceptions yet. We will just be sure the data in our objects are valid. Follow the directions below to add error checking to each class.

Use proper if structure. Do not do unnecessary tests . Do not have empty if or else blocks

Window (hw4)

• In the constructor, if either the width or the height parameter is <= 0, set both width and height to 0
• In setDimensions, only change the width and the height if both are > 0. If either is 0, don't make any changes.

GroceryBill (hw3)

• In add method: only add the amount if it is greater than 0
• In remove method: only remove the amount if it is greater than 0 and also less than or equal to the subtotal 

Hal9000 (hw3)

• Modify both the constructor and the setName method as follows
  • Restrict the name to 8 characters. If the name contains more than 8 characters, set the first 8 characters as the crewmember's name
  • If the parameter is Robert, set the name to Bob

If you do not have a correct version of one of these classes, you can get it from the posted solutions.

For the draft, make the changes to Window

5B draft:
5B final:

5C

Write a class called TwoNumbers which will ask the user for two numbers and print out comments based on their values. (no starter file. You will write all the code)

Use this exact prompt to get input:

System.out.print("Enter two numbers (like this: 41.7 -22.5): ");

The user will enter both numbers on the same line at the same time. This is possible because the first call to nextDouble will skip any leading whitespaces and then read up to the next whitespace (the space), leaving that whitespace in the input stream. The second call to nextDouble will ignore leading whitespaces and then read up to the next whitespace (the newline) leaving the newline in the input stream. This is a handy way to request multiple inputs.

Here are the conditions and the comments to print.

If the numbers are equal only print the one message. Otherwise print all that apply. Copy and paste the prompt and the replies. That way you will have exactly what Codecheck expects. Print the comments in the order given above

Use the appropriate if structure and do not just use all ifs.

Note for advanced students: Do not use System.exit()

For the draft, get the numbers from the user and print the appropriate one of the first 3 comments.

5C draft:
5C final: