Java List 泛型字段平均值计算 - 高效方法与示例

"可以通过遍历List，将每个元素的特定字段值累加起来，然后除以List的大小得到平均值。\n\n假设List的泛型是T，T类中有一个字段是field，可以这样实现：\n\njava\npublic static <T> double getAverage(List<T> list, Function<T, Double> fieldExtractor) {\n double sum = 0;\n for (T t : list) {\n sum += fieldExtractor.apply(t);\n }\n return sum / list.size();\n}\n\n\n使用示例：\n\n假设有一个Student类，有一个字段是score，可以这样调用getAverage方法：\n\njava\nList<Student> students = new ArrayList<>();\nstudents.add(new Student(\"Alice\", 85));\nstudents.add(new Student(\"Bob\", 90));\nstudents.add(new Student(\"Charlie\", 75));\n\ndouble averageScore = getAverage(students, Student::getScore);\nSystem.out.println(\"Average score: \" + averageScore);\n\n\n其中，Student类的定义如下：\n\njava\npublic class Student {\n private String name;\n private double score;\n\n public Student(String name, double score) {\n this.name = name;\n this.score = score;\n }\n\n public String getName() {\n return name;\n }\n\n public double getScore() {\n return score;\n }\n}\n\n\n运行结果为：\n\n\nAverage score: 83.33333333333333\n\n