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Inner 3

Java Multithreading, Level 3, Lesson 4

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I do not really get what the last two requirements want, It seems to me everything is okay.

Inside the Solution class:
1) use Task and MockDB to implement the private class TaskDataProvider, whose purpose is to update the tasks field.
2) use String and MockDB to implement the private class NameDataProvider, whose purpose is to update the names field.

Requirements:

The TaskDataProvider class must be inside the Solution class and must be private.
The NameDataProvider class must be inside the Solution class and must be private.
The TaskDataProvider class must implement the DbDataProvider interface with a Task parameter.
The NameDataProvider class must implement the DbDataProvider interface with a String parameter.
The refreshAllData method in the TaskDataProvider class must save the result of the MockDB class's getFakeTasks method in the tasks list.
The refreshAllData method in the NameDataProvider class must save the result of the MockDB class's getFakeNames method in the names list.

package com.codegym.task.task23.task2304; import javax.naming.Name; import java.util.Collection; import java.util.List; import java.util.Map; import java.util.Objects; import java.util.function.UnaryOperator; /* Inner 3 */ public class Solution { private List<Task> tasks; private List<String> names; private DbDataProvider taskDataProvider = new TaskDataProvider(); private DbDataProvider nameDataProvider = new NameDataProvider(); public void refresh() { Map taskCriteria = MockView.getFakeTaskCriteria(); taskDataProvider.refreshAllData(taskCriteria); Map nameCriteria = MockView.getFakeNameCriteria(); nameDataProvider.refreshAllData(nameCriteria); } private class TaskDataProvider implements DbDataProvider<Task> { @Override public void refreshAllData(Map criteria) { Solution.this.tasks.addAll(Objects.requireNonNull(MockDB.getFakeTasks(criteria))); } } private class NameDataProvider implements DbDataProvider<String> { @Override public void refreshAllData(Map criteria) { Solution.this.names.addAll(Objects.requireNonNull(MockDB.getFakeNames(criteria))); } } private interface DbDataProvider<T> { void refreshAllData(Map criteria); } class Task { } public static void main(String[] args) { } }

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Wei Cui

Level 39 , Newark, United States

24 March 2020, 14:37

private class TaskDataProvider implements DbDataProvider{

        @Override
        public void refreshAllData(Map criteria) {
            tasks = MockDB.getFakeTasks(criteria);
        }
    }

    private class NameDataProvider implements DbDataProvider{

        @Override
        public void refreshAllData(Map criteria) {
            names = MockDB.getFakeNames(criteria);
        }
    }

Azja

Level 32 , Krakow, Poland

25 September 2019, 15:44

solution

They want to assign list from MockDB

Solution.this.tasks = MockDB.getFakeTasks(criteria);

Think about this that way. If something is already in "names" list and you call at it "addAll", it'll add all data from data base to end of the list. If you call this few time there'll be some troubles. They want update so just take list from data base and assign this to yours list

+10