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Java Java Data Structures - Retired Exploring the Java Collection Framework Sets

think my biggest problem is my understading of generic or object.

anyone that look at my code that know with direction should i take? Please dont give me the answer i really desire to be really good at programming and that comes with work. but guide me on what can i do to improve on this topic.

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.List;
import java.util.Set;
import java.util.TreeSet;

public class Blog {
  List<BlogPost> mPosts;

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

  public List<String> getAllAuthor(){
    Set<String> author = new TreeSet<String>();    
    for(mPost Author: mPost.getAuthor()){
      author.addAll(Author);
    }
    return author;
  }


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

1 Answer

What is the question? What is the error your are seeing?

This is wrong

    public List<String> getAllAuthor(){
        Set<String> author = new TreeSet<String>();
        for(mPost Author: mPost.getAuthor()){
            author.addAll(Author);
        }
        return author;
    }

typically this should be

for(SomeObject objectItem: an iterableThatHasSomeObject (s)){ .... }

Re-review this part and you will figure it out