Java Stream list转map，Map<Long, String>，以单个属性为键，单个属性为值，Duplicate key 100 (attempted merging values a and e)

Java Stream List 转 Map，以单个属性为键，单个属性为值，Duplicate key 100 (attempted merging values a and e)

当单个属性为键，为值时，出现重复，添加 (s1, s2) -> s1， 去重；

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, "e"));

// List对象，转Map
Map<Long, String> usernameMap = list.stream()
        .collect(Collectors.toMap(FaAdmin::getId, FaAdmin::getUsername, (eo1, eo2) -> eo2));

System.out.println(usernameMap);