Answer by Mathias G. for How to sort List of objects by some property

Since Java8 this can be done even cleaner using a combination of Comparator and Lambda expressions

For Example:

class Student{    private String name;    private List<Score> scores;    // +accessor methods}class Score {    private int grade;    // +accessor methods}

    Collections.sort(student.getScores(), Comparator.comparing(Score::getGrade);