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Start your free trialIsha Mandrekar
4,013 PointsFacing problem in compareTo implementation
I am getting error in my program that it is not able to identify private variables of the argument object in the compareTo implementation method. Can someone help please.
package com.example;
import java.util.Date;
public class BlogPost implements Comparable
{
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[] 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;
}
public int compareTo(Object obj)
{
obj = (BlogPost) obj;
if (equals(obj))
{
return 0;
}
int cmp = this.mCreationDate.compareTo(obj.mCreationDate);
if ( cmp == 0)
{
return (this.mTitle.compareTo(obj.mTitle));
}
return (this.mCreationDate.compareTo(obj.mCreationDate));
}
}
1 Answer
jcorum
71,830 PointsHere you go:
public int compareTo(Object o) {
BlogPost other = (BlogPost) o; //cast o to BlogPost
if (this == other) { //check for equality
return 0;
} else if (this.getCreationDate().before(other.getCreationDate())) { //compare Dates, using before() method
return -1;
} else {
return 1;
}
}