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

sankalp yadav
sankalp yadav
2,101 Points

Whats wrong with this code ?

I wrote like this
do am i missing some logic here.

  public List<String> getExternalLinks()
  {
     ArrayList<String>  container =new ArrayList<String>();  

    for(String dummy: getWords())
    {
      if (dummy.startsWith("http"))  container.add(dummy);
    }
    return container;
  }

If there is syntax error , you can tell me , but i am not here for syntax error as i am new to this java so such mistakes are predictable.

Thanks

com/example/BlogPost.java
package com.example;

import java.io.Serializable;
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 List<String> getExternalLinks()
  {
     ArrayList<String>  container =new ArrayList<String>();  

    for(String dummy: getWords())
    {
      if (dummy.startsWith("http"))  container.add(dummy);
    }
    return container;
  }

  public int compareTo(BlogPost other) {
    if (equals(other)) {
      return 0;
    }
    return mCreationDate.compareTo(other.mCreationDate);
  }

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

  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;
  }
}

2 Answers

andren
andren
28,558 Points

Your logic and code is fine, the issue is that you are missing an import statement for the ArrayList class.

If you add:

import java.util.ArrayList;

To the list of imports then your code will work.

sankalp yadav
sankalp yadav
2,101 Points

Ok thanks and what is difference between these two List<String> container =new ArrayList<String>();
and ArrayList<String> container =new ArrayList<String>();