例子1
@Data //lombok提供的注解,会自动添加getter和setter
public class Student {
private String id;
private String name;
private String info;
}
Map<String, Student> studentMap = list.stream().collect(Collectors.toMap(Student::getId, Function.identity()));
if(studentMap.containsKey(studentNew.getId())) {
System.out.println("studentNew in map!");
}
例子2