diff --git a/core-java-collections/src/main/java/com/baeldung/performance/Employee.java b/core-java-collections/src/main/java/com/baeldung/performance/Employee.java index d811cfbb7d..1ed4410371 100644 --- a/core-java-collections/src/main/java/com/baeldung/performance/Employee.java +++ b/core-java-collections/src/main/java/com/baeldung/performance/Employee.java @@ -44,4 +44,12 @@ public class Employee { result = 31 * result + name.hashCode(); return result; } + + @Override + public String toString() { + return "Employee{" + + "id=" + id + + ", name='" + name + '\'' + + '}'; + } } diff --git a/core-java-collections/src/main/java/com/baeldung/sort/Employee.java b/core-java-collections/src/main/java/com/baeldung/sort/Employee.java new file mode 100644 index 0000000000..b5e56f6141 --- /dev/null +++ b/core-java-collections/src/main/java/com/baeldung/sort/Employee.java @@ -0,0 +1,60 @@ +package com.baeldung.sort; + +public class Employee implements Comparable { + + private Long id; + private String name; + + public Employee(Long id, String name) { + this.name = name; + this.id = id; + } + + public Long getId() { + return id; + } + + public void setId(Long id) { + this.id = id; + } + + public String getName() { + return name; + } + + public void setName(String name) { + this.name = name; + } + + @Override + public boolean equals(Object o) { + if (this == o) return true; + if (o == null || getClass() != o.getClass()) return false; + + Employee employee = (Employee) o; + + if (!id.equals(employee.id)) return false; + return name.equals(employee.name); + + } + + @Override + public int hashCode() { + int result = id.hashCode(); + result = 31 * result + name.hashCode(); + return result; + } + + @Override + public String toString() { + return "Employee{" + + "id=" + id + + ", name='" + name + '\'' + + '}'; + } + + @Override + public int compareTo(Employee employee) { + return (int)(this.id - employee.getId()); + } +} diff --git a/core-java-collections/src/main/java/com/baeldung/sort/SortHashMap.java b/core-java-collections/src/main/java/com/baeldung/sort/SortHashMap.java new file mode 100644 index 0000000000..b8a2b32060 --- /dev/null +++ b/core-java-collections/src/main/java/com/baeldung/sort/SortHashMap.java @@ -0,0 +1,104 @@ +package com.baeldung.sort; + +import com.google.common.base.Functions; +import com.google.common.collect.ImmutableSortedMap; +import com.google.common.collect.Lists; +import com.google.common.collect.Ordering; + +import java.util.*; +import java.util.stream.Collectors; + +public class SortHashMap { + + private static Map map = new HashMap<>(); + + public static void main(String[] args) { + + initialize(); + + treeMapSortByKey(); + + arrayListSortByValue(); + arrayListSortByKey(); + + sortStream(); + + sortGuava(); + + addDuplicates(); + + treeSetByKey(); + treeSetByValue(); + + } + + private static void sortGuava() { + final Ordering naturalOrdering = + Ordering.natural().onResultOf(Functions.forMap(map, null)); + + System.out.println(ImmutableSortedMap.copyOf(map, naturalOrdering)); + } + + private static void sortStream() { + map.entrySet().stream() + .sorted(Map.Entry.comparingByKey().reversed()) + .forEach(System.out::println); + + Map result = map.entrySet().stream() + .sorted(Map.Entry.comparingByValue()) + .collect(Collectors.toMap(Map.Entry::getKey, Map.Entry::getValue, + (oldValue, newValue) -> oldValue, LinkedHashMap::new)); + + result.entrySet().forEach(System.out::println); + } + + private static void treeSetByValue() { + SortedSet values = new TreeSet<>(map.values()); + System.out.println(values); + } + + private static void treeSetByKey() { + SortedSet keysSet = new TreeSet<>(map.keySet()); + System.out.println(keysSet); + } + + private static void treeMapSortByKey() { + TreeMap sorted = new TreeMap<>(map); + sorted.putAll(map); + + sorted.entrySet().forEach(System.out::println); + + } + + private static void arrayListSortByValue() { + List employeeById = new ArrayList<>(map.values()); + + Collections.sort(employeeById); + + System.out.println(employeeById); + } + + private static void arrayListSortByKey() { + List employeeByKey = new ArrayList<>(map.keySet()); + Collections.sort(employeeByKey); + System.out.println(employeeByKey); + } + + private static void initialize() { + Employee employee1 = new Employee(1L, "Mher"); + map.put(employee1.getName(), employee1); + Employee employee2 = new Employee(22L, "Annie"); + map.put(employee2.getName(), employee2); + Employee employee3 = new Employee(8L, "John"); + map.put(employee3.getName(), employee3); + Employee employee4 = new Employee(2L, "George"); + map.put(employee4.getName(), employee4); + } + + private static void addDuplicates() { + Employee employee5 = new Employee(1L, "Mher"); + map.put(employee5.getName(), employee5); + Employee employee6 = new Employee(22L, "Annie"); + map.put(employee6.getName(), employee6); + } +}