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Java Java Data Structures Exploring the Java Collection Framework ArrayLists

sankalp yadav
sankalp yadav
2,101 Points
Posted by 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
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
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>();