com.doctor.java8.GroupingTheData.java Source code

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Here is the source code for com.doctor.java8.GroupingTheData.java

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/*
 * Copyright (C) 2014- now() The  openSourcLibrary-2015  Authors
 *
 * https://github.com/sdcuike
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.doctor.java8;

import java.util.Arrays;
import java.util.List;
import java.util.Map;
import java.util.Objects;
import java.util.stream.Collectors;

import org.apache.commons.lang3.builder.ToStringBuilder;

/**
 * Grouping the Data
 * 
 * @author doctor
 *
 * @time 2015812 ?12:08:31
 */
public class GroupingTheData {

    public static void main(String[] args) {
        List<Person> persons = Arrays.asList(new Person("doctor", "man", "address-1"),
                new Person("doctor who ", "man", "address-1"), new Person("doctor me", "woman", "address-2"));
        Map<String, List<Person>> map = persons.stream().collect(Collectors.groupingBy(Person::getSex));
        System.out.println(map);

        Map<String, Map<String, List<Person>>> map2 = persons.stream()
                .collect(Collectors.groupingBy(Person::getSex, Collectors.groupingBy(Person::getAddress)));
        System.out.println(map2);
    }

    private static class Person {
        private String name;
        private String sex;
        private String address;

        public Person(String name, String sex, String address) {
            this.name = name;
            this.sex = sex;
            this.address = address;
        }

        public String getName() {
            return name;
        }

        public void setName(String name) {
            this.name = name;
        }

        public String getSex() {
            return sex;
        }

        public void setSex(String sex) {
            this.sex = sex;
        }

        public String getAddress() {
            return address;
        }

        public void setAddress(String address) {
            this.address = address;
        }

        @Override
        public int hashCode() {
            return Objects.hash(name, sex, address);
        }

        @Override
        public boolean equals(Object obj) {
            if (this == obj) {
                return true;
            }

            if (obj instanceof Person) {
                Person person = (Person) obj;
                return name.equals(person.name) && sex.equals(person.sex) && address.equals(person.address);
            }

            return false;
        }

        @Override
        public String toString() {

            return ToStringBuilder.reflectionToString(this);
        }
    }
}