Java Stream list转map，Map<String, T>，以元素对象某个属性为KEY，对象实体为VALUE，组建Map

Java Stream List 转 Map，以元素对象某个属性为KEY，对象实体为VALUE，组建Map

List<FaAdmin> list = Lists.newArrayList();
list.add(new FaAdmin(100L, "a"));
list.add(new FaAdmin(101L, "b"));
list.add(new FaAdmin(102L, "c"));
list.add(new FaAdmin(100L, "a"));

// List对象，转Map，以元素对象某个属性为KEY，对象实体为VALUE，组建Map
Map<String, FaAdmin> usernameMap = list.stream()
        .collect(Collectors.toMap(FaAdmin::getUsername, eo -> eo));

System.out.println(usernameMap);