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Diego Marrs
8,243 PointsAm...I doing anything wrong?
Hello,
I get this error every time I run my program...but the thing is, the error looks like it's in another file:
JavaTester.java:67: error: constructor Course in class Course cannot be applied to given types;
Course course = new Course("Java Data Structures");
^
required: String,Set
found: String
reason: actual and formal argument lists differ in length
Note: JavaTester.java uses unchecked or unsafe operations.
Note: Recompile with -Xlint:unchecked for details.
1 error
package com.example.model;
import java.util.List;
import java.util.Set;
public class Course {
private String mTitle;
private Set<String> mTags;
public Course(String title, Set<String> tags) {
mTitle = title;
// TODO: initialize the set mTags
mTags = tags;
}
public void addTag(String tag) {
// TODO: add the tag
}
public void addTags(List<String> tags) {
// TODO: add all the tags passed in
}
public boolean hasTag(String tag) {
// TODO: Return whether or not the tag has been added
return false;
}
public String getTitle() {
return mTitle;
}
}
Please help!
2 Answers

Seth Kroger
56,403 PointsIt's telling you there's a mismatch in the arguments the constructor is expected to take. You aren't necessarily supposed to alter the arguments for the constructor; just initialize the tags as an empty set.

Seth Kroger
56,403 PointsYou need to construct a new set:
mTags = new HashSet<>(); // or new TreeSet<>(); Don't forget to import whichever one you use.

Diego Marrs
8,243 PointsThanks! Man, I miss a lot of small details...
Diego Marrs
8,243 PointsDiego Marrs
8,243 PointsAh okay.
I'm initializing the tags as empty sets, but I get this error: