Sort the object list based on different data members in Java

I have this course:

public class Friend {

private String name;
private String location;
private String temp;
private String humidity;

public String getTemp() {
    return temp;
}

public void setTemp(String temp) {
    this.temp = temp;
}

public String getHumidity() {
    return humidity;
}

public void setHumidity(String humidity) {
    this.humidity = humidity;
}

public String getName() {
    return name;
}

public void setName(String name) {
    this.name = name;
}


public String getLocation() {
    return location;
}

public void setLocation(String location) {
    this.location = location;
}
}

I want to sort the list according to the name, location, temperature and humidity entered by the user Edit: the user specifies which data member must be sorted What is the easiest way? thank you.

Solution

Java has a called collections The static function of sort (list, comparator), which sorts a (general) object list given a custom comparator, and determines which one is sorted before the other given two objects of the same type

Your task is to write a function that creates a comparator that sorts objects according to parameters and user specified sorting order For example:

public Comparator<Friend> getComparator(final String sortBy) {
  if ("name".equals(sortBy)) {
    return new Comparator<Friend>() {
      @Override int compare(Friend f1,Friend f2) 
        return f1.getName().compareTo(f2.getName());
      }
    };
  } else if ("location".equals(sortBy)) {
    return new Comparator<Friend>() {
      @Override int compare(Friend f1,Friend f2) 
        return f1.getLocation().compareTo(f2.getLocation());
      }
    };
  } else if ("temp".equals(sortBy)) {
    // ...
  } else {
    throw new IllegalArgumentException("invalid sort field '" + sortBy + "'");
  }
}