Method exercises

1
Method exercises

• Method exercises
• Without IF

2
Setup

• Create one new project to hold all of these.
• In that project, create an empty class called
  WorkIt to hold all of your methods.

3
First problem

• 1. ProfitOnOneSale

4
ProfitOnOneSale

• Step 1 Write the comment for your method
• Open the class
• Locate the curly brace that closed the last
  method. If it is the first, it should go right
  after the open curly brace for the class.
• Write the comments
• public class WorkIt
• /
• profitOnOneSale Calculate profit on
  one sale
• given the cost and price
• _at_param double price - the price that
  comes in
• double cost the cost
  that comes in
• _at_return double profit price
  minus cost
• /

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ProfitOnOneSale Step 2

• Step 2 write the method header
• Under the bracket, or after the end of another
  method, write public static
• Write the type of your result (ex int). If it
  returns nothing, write void.
• Write the name of your method
• Between parentheses, write the type of your input
  followed by the name of the variable your method
  will use. If you have more than one, separate by
  commas. Every variable needs a type before it.
• Type an open and close curly brace.

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ProfitOnOneSale Step 2 Result

• public class WorkIt
• /
• profitOnOneSale Calculate profit on
  one sale
• given the cost and price
• _at_param double price - the price that
  comes in
• double cost the cost
  that comes in
• _at_return double profit price
  minus cost
• /
• public static double profitOnOneSale
  (double price, double cost)

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ProfitOnOneSale Step 3

• Step 3 Send back a dummy result so it will
  compile
• Type return
• Type a value that would be valid for the return
  type.
• Type a semicolon
• Compile to see no errors.
• Ex return 3

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Step 4 write the test case

• Step 4 write the test case
• Right click on the workit class and select
  create test case
• Right click on the test case and select create
  test method
• Right click on the workit class and select
  profitOnOneSale method. Name the test
  profitOnOneSaleTest1 and Enter some inputs and
  then enter the expected result.
• Repeat for about 3 test cases.

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Step 4 result

• public class WorkIt
• /
• profitOnOneSale Calculate profit on
  one sale
• given the cost and price
• profitOnOneSale(6,2.5) 3.5
• profitOnOneSale(2,3) -1.0
  profitOnOneSale(6.5,0) 6.5

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Step 5 code inside the method

• Knowing you have a box in memory for every input
  variable already, code inside the methods curly
  braces so that the proper return value will be
  sent back.
• This is very specific to every type of problem.
• Compile

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Step 5 result

• public class WorkIt
• /
• ProfitOnOneSale Calculate profit on
  one sale
• given the cost and price
• _at_param double price - the price that
  comes in
• double cost the cost
  that comes in
• _at_return double profit price
  minus cost
• /
• public static double profitOnOneSale
  (double price, double cost)
• return price - cost

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Step 6 test it

• Compile and run your method.
• Run it for each of your test cases (right click
  on the test case and choose Test All
• Click on view / test results to see which tests
  passed