Chapter 18, Problem 8PP

Program Plan Intro

Implementing the method “map()”

Program plan:

Filename: “Pair.java”

This code snippet creates a class “Pair”. In the code,

• Define a class “Pair”.
  • Declare the class members “first” and “second”.
  • Define the constructor “Pair()”.
    • Set the class members.
  • Define the getter “getFirst()”.
    • Return the value of “first”.
  • Define the getter “getSecond()”.
    • Return the value of “second”.

Filename: “ListUtil.java”

This code snippet creates an interface “ListUtil”. In the code,

• Import the required packages.
• Define a class “ListUtil”.
  • Define the generic method “map()”.
    • Create a list “result” of type “List<T>”.
    • Iterate a “for” loop,
      • Add elements to “result”.
    • Return “result”.

Filename: “MapTester.java”

This code snippet creates a class “MapTester”. In the code,

• Define a class “MapTester”.
  • Define the “main” method.
    • Define a string array “words”.
    • Create a list “wordsList”.
    • Call the method “map()” and set the result to “sizes”.
    • Create an iterator “iter”.
    • Print the token of “wordsList” using “iter”.
    • Print “first=second”.
    • Print the expected token.
    • Print the token of “wordsList” using “iter”.
    • Print “first=second”.
    • Print the expected token.
    • Create an iterator “intItr”.
    • Print the token of “wordsList” using “iter”.
    • Print “first=second”.
    • Print the expected token.
    • Print the token of “wordsList” using “iter”.
    • Print “first=second”.
    • Print the expected token.