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Thread: Help me solve/understand this question. I have tried googling so much but failed.

  1. #1
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    Default Help me solve/understand this question. I have tried googling so much but failed.

    The question:
    Fix the following code so the the map.get() call retrieves the expected value. Do not change the main method.

    import java.util.HashMap;
    import java.util.Map;

    public class StudentTest {
    public static final class Student {
    public Student( String name ) {
    this.name = name;
    }
    private String name;
    }

    public static void main(final String[] args ) {
    Map<Student, String> map = new HashMap<>();
    map.put( new Student( "john"), "present" );
    System.out.println( map.get( new Student( "john" ) ) );
    }
    }

    Now I know I can get the answer by changing the main method like so:
    Student s = new Student("john")
    System.out.println( map.get( s) );

    but how can I achieve this without changing the main method?

  2. #2
    Super Moderator Norm's Avatar
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    Default Re: Help me solve/understand this question. I have tried googling so much but failed.

    Have you read the API doc for the Map class's get method to see what it does and what it uses?
    Basically you need to add some methods to the Student class so that get works.
    The API doc http://docs.oracle.com/javase/8/docs/api/index.html

    Please edit your post and wrap your code with code tags:

    [code]
    **YOUR CODE GOES HERE**
    [/code]

    to get highlighting and preserve formatting.
    If you don't understand my answer, don't ignore it, ask a question.

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