Sets Objective For Loop

Question

I'm having trouble construction the proper for loop for this objective I tried to initialize the getAuthor method from the BlogPost class but i don't have the right amount of arguments when i try to do so anybody have any help advice for this one? would be greatly appericiated

com/example/BlogPost.java

package com.example;

import java.io.Serializable;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;


public class BlogPost implements Comparable<BlogPost>, Serializable {
  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 int compareTo(BlogPost other) {
    if (equals(other)) {
      return 0;
    }
    return mCreationDate.compareTo(other.mCreationDate);
  }

  public String[] getWords() {
    return mBody.split("\\s+");
  }

  public List<String> getExternalLinks() {
    List<String> links = new ArrayList<String>();
    for (String word : getWords()) {
      if (word.startsWith("http")) {
        links.add(word);
      }
    }
    return links;
  }

  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;
  }
}

com/example/Blog.java

package com.example;
import java.util.Set;
import java.util.TreeSet;
import java.util.HashSet;
import java.util.List;

public class Blog {
  List<BlogPost> mPosts;

  public Blog(List<BlogPost> posts) {
    mPosts = posts;
  }

  public List<BlogPost> getPosts() {
    return mPosts;
  }

  public Set<String> getAllAuthors() {
  Set<String> allAuthors = new TreeSet<String>();
  for (BlogPost BlogPost; Blog;) {
    allAuthors.add(BlogPost.getAuthor());
  }
    return allAuthors;
  }
}

Answer 1 · 2016-08-12T04:23:18Z

August 12, 2016 4:23am

The problem is your use of the foreach loop.

for (BlogPost BlogPost; Blog;) {
    allAuthors.add(BlogPost.getAuthor());
}

should be

for (BlogPost blogPost : mPosts) {
    allAuthors.add(blogPost.getAuthor());
}

Remember that this type of for loops iterates for all elements in the list given after the :, where each element are represented by the variable declared before the :

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Fredrick Reid

Fredrick Reid

Sets Objective For Loop

1 Answer

Benjamin Barslev Nielsen

Benjamin Barslev Nielsen