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Start your free trialSimon Feuster
Full Stack JavaScript Techdegree Graduate 28,036 PointsReturn object obj type casted as a String if it is in fact a String
Can someone help me please. I don't get it :(
package com.example;
import java.util.Date;
public class BlogPost {
private String mAuthor;
private String mTitle;
private String mBody;
private String mCategory;
private Date mCreationDate;
public BlogPost(String author, String title, String body, String category, Date creationDate) {
mAuthor = author;
mTitle = title;
mBody = body;
mCategory = category;
mCreationDate = creationDate;
}
public String getAuthor() {
return mAuthor;
}
public String getTitle() {
return mTitle;
}
public String getBody() {
return mBody;
}
public String getCategory() {
return mCategory;
}
public Date getCreationDate() {
return mCreationDate;
}
}
import com.example.BlogPost;
public class TypeCastChecker {
/***************
I have provided 2 hints for this challenge.
Change `false` to `true` in one line below, then click the "Check work" button to see the hint.
NOTE: You must set all the hints to false to complete the exercise.
****************/
public static boolean HINT_1_ENABLED = false;
public static boolean HINT_2_ENABLED = false;
public static String getTitleFromObject(Object obj) {
String result = "";
if (obj instanceof String) {
result = obj;
}
return result;
}
}
2 Answers
Trent Christofferson
18,846 PointsYou need to cast obj to String when setting result = obj
result = (String) obj;
Rares Conea
Courses Plus Student 15,000 PointsEven if obj is of type String and the if statement evaluates to true the assigning you are trying to do won t compile because Object is a super type of String. When trying to cast from supertype to subtype you need to add the type of the subtype you want in (), as in the example "result = (String) obj"(Downcastig), while the oposite can be done without casting "An Object reference can point to anything(because Object is the class from which all other classes inherit) without casting <obj = result> will compile"(Upcasting does not require ())