From 8888479b6c79934846dbee87288c2e1dbce620d3 Mon Sep 17 00:00:00 2001
From: jez04 <david.jezek@post.cz>
Date: Mon, 7 Oct 2024 22:48:49 +0200
Subject: [PATCH] feat: solution
---
pom.xml | 4 +-
.../cz/vsb/fei/efrei/lab03/DangerWorld.java | 50 ----
.../fei/efrei/lab03/WorkWithCollections.java | 225 ------------------
.../AlreadyDeadException.java | 2 +-
.../fei/efrei/{lab03 => lab04}/Fighter.java | 2 +-
.../vsb/fei/efrei/{lab03 => lab04}/Hero.java | 11 +-
.../vsb/fei/efrei/lab04/HeroWithEquals.java | 27 +++
.../lab04/HeroWithEqualsAndBadHashcode.java | 32 +++
.../HeroWithEqualsAndConstantHashcode.java | 32 +++
.../lab04/HeroWithEqualsAndHashcode.java | 32 +++
.../fei/efrei/{lab03 => lab04}/Monster.java | 2 +-
.../cz/vsb/fei/efrei/lab04/Stopwatch.java | 34 +++
.../vsb/fei/efrei/{lab03 => lab04}/Utils.java | 2 +-
.../fei/efrei/lab04/WorldOfCollections.java | 177 ++++++++++++++
14 files changed, 346 insertions(+), 286 deletions(-)
delete mode 100644 src/main/java/cz/vsb/fei/efrei/lab03/DangerWorld.java
delete mode 100644 src/main/java/cz/vsb/fei/efrei/lab03/WorkWithCollections.java
rename src/main/java/cz/vsb/fei/efrei/{lab03 => lab04}/AlreadyDeadException.java (90%)
rename src/main/java/cz/vsb/fei/efrei/{lab03 => lab04}/Fighter.java (88%)
rename src/main/java/cz/vsb/fei/efrei/{lab03 => lab04}/Hero.java (83%)
create mode 100644 src/main/java/cz/vsb/fei/efrei/lab04/HeroWithEquals.java
create mode 100644 src/main/java/cz/vsb/fei/efrei/lab04/HeroWithEqualsAndBadHashcode.java
create mode 100644 src/main/java/cz/vsb/fei/efrei/lab04/HeroWithEqualsAndConstantHashcode.java
create mode 100644 src/main/java/cz/vsb/fei/efrei/lab04/HeroWithEqualsAndHashcode.java
rename src/main/java/cz/vsb/fei/efrei/{lab03 => lab04}/Monster.java (97%)
create mode 100644 src/main/java/cz/vsb/fei/efrei/lab04/Stopwatch.java
rename src/main/java/cz/vsb/fei/efrei/{lab03 => lab04}/Utils.java (97%)
create mode 100644 src/main/java/cz/vsb/fei/efrei/lab04/WorldOfCollections.java
diff --git a/pom.xml b/pom.xml
index dbb5b78..310f993 100644
--- a/pom.xml
+++ b/pom.xml
@@ -3,10 +3,10 @@
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>cz.vsb.fei.efrei</groupId>
- <artifactId>efrei-lab03</artifactId>
+ <artifactId>efrei-lab04</artifactId>
<version>0.0.1-SNAPSHOT</version>
- <name>efrei-lab03</name>
+ <name>efrei-lab04</name>
<packaging>jar</packaging>
diff --git a/src/main/java/cz/vsb/fei/efrei/lab03/DangerWorld.java b/src/main/java/cz/vsb/fei/efrei/lab03/DangerWorld.java
deleted file mode 100644
index 8778279..0000000
--- a/src/main/java/cz/vsb/fei/efrei/lab03/DangerWorld.java
+++ /dev/null
@@ -1,50 +0,0 @@
-package cz.vsb.fei.efrei.lab03;
-
-import java.util.ArrayList;
-import java.util.List;
-import java.util.Random;
-import java.util.Scanner;
-
-public class DangerWorld {
- private static final Random RANDOM = new Random();
-
- public static void main(String[] args) {
- List<Fighter> fighters = new ArrayList<>();
-
- generateMonstersAndHeros(fighters);
-
- WorkWithCollections.playWithCollections(fighters);
-
- }
-
- private static void generateMonstersAndHeros(List<Fighter> fighters) {
- try (Scanner s = new Scanner(System.in)) {
- System.out.println("Type name of monster:");
- String name = s.next();
-
- Monster monster = new Monster(name);
- fighters.add(monster);
- } catch (Exception e) {
- System.out.println("Cannot properlly read name from STDIN. Continu without named monster");
- }
- fighters.add(new Monster("King"));
- fighters.add(new Monster("Queen"));
- fighters.add(new Monster("Fairy"));
- fighters.add(new Hero("Shrek"));
- fighters.add(new Hero("Cinderela"));
-
- int countOfHeros = RANDOM.nextInt(200);
- for (int i = 0; i < countOfHeros; i++) {
- fighters.add(new Hero(Utils.generateHeroName()));
- }
-
- int countOfMonsters = RANDOM.nextInt(250);
- for (int i = 0; i < countOfMonsters; i++) {
- fighters.add(new Monster(Utils.generateMonsterName()));
- }
- }
-
-
-
-
-}
diff --git a/src/main/java/cz/vsb/fei/efrei/lab03/WorkWithCollections.java b/src/main/java/cz/vsb/fei/efrei/lab03/WorkWithCollections.java
deleted file mode 100644
index d7a8f74..0000000
--- a/src/main/java/cz/vsb/fei/efrei/lab03/WorkWithCollections.java
+++ /dev/null
@@ -1,225 +0,0 @@
-package cz.vsb.fei.efrei.lab03;
-
-import java.util.ArrayList;
-import java.util.HashMap;
-import java.util.Iterator;
-import java.util.List;
-import java.util.Map;
-
-public class WorkWithCollections {
-
- public static void playWithCollections(List<Fighter> fighters) {
- calculateAverageStrenght(fighters);
- calculateAverageLives(fighters);
-
- System.out.println("=========================================================");
- makeFights(fighters, 1000);
- System.out.println("=========================================================");
-
- calculateAverageLives(fighters);
- System.out.println("=========================================================");
-
- try {
- removeDeadsCauseException(fighters);
- printDeadAndlives(fighters);
- } catch (Exception e) {
- e.printStackTrace();
- System.out.println("Continue! Expected exception");
- }
- System.out.println("=========================================================");
-
- //use copy of list
- int countDeath = removeDeadsUsingAnotherCollection(new ArrayList<>(fighters));
- System.out.println("Number of deats:" + countDeath);
- System.out.println("=========================================================");
-
- //use copy of list
- countDeath = removeDeadsUsingIndexWithMistakes(new ArrayList<>(fighters));
- System.out.println("Number of deats:" + countDeath);
- System.out.println("=========================================================");
-
- //use copy of list
- countDeath = removeDeadsUsingIndex(new ArrayList<>(fighters));
- System.out.println("Number of deats:" + countDeath);
- System.out.println("=========================================================");
-
- countDeath = removeDeadsUsingIterator(fighters);
- System.out.println("Number of deats:" + countDeath);
- System.out.println("=========================================================");
-
-
- for (Fighter fighter2 : fighters) {
- if (!fighter2.isAlive()) {
- System.out.println("Fount dead fighter " + fighter2.getName());
- }
- }
-
- Map<String, Integer> namesCountMap = new HashMap<>();
- countFrequencyOfNames(fighters, namesCountMap);
-
- printOutAllNamesAndTheirCount(namesCountMap);
-
-
- }
-
- private static void makeFights(List<Fighter> fighters, int rounds) {
- for (int i = 0; i < rounds; i++) {
- Fighter fighter1 = fighters.get(Utils.RANDOM.nextInt(fighters.size()));
- Fighter fighter2 = fighters.get(Utils.RANDOM.nextInt(fighters.size()));
- try {
- fighter1.attackedBy(fighter2);
- } catch (AlreadyDeadException e) {
- System.out.println("Ups! Fighter " + fighter2.getName() + " attack already dead " + fighter1.getName());
- }
- }
- }
-
- private static int removeDeadsCauseException(List<Fighter> fighters) {
- int countDeath = 0;
- List<Fighter> deads = new ArrayList<>();
- //use foreach loop that use iterator
- for (Fighter fighter : fighters) {
- if (!fighter.isAlive()) {
- countDeath++;
- /*cannot remove from collection which is iterated*/
- fighters.remove(fighter);
- }
- }
- fighters.removeAll(deads);
- return countDeath;
- }
-
- private static int removeDeadsUsingAnotherCollection(List<Fighter> fighters) {
- System.out.println("Remove using another collection");
- printDeadAndlives(fighters);
- int countDeath = 0;
- List<Fighter> deads = new ArrayList<>();
- for (Fighter fighter : fighters) {
- if (!fighter.isAlive()) {
- countDeath++;
- deads.add(fighter);
- }
- }
- fighters.removeAll(deads);
- printDeadAndlives(fighters);
- return countDeath;
- }
-
- private static int removeDeadsUsingIndexWithMistakes(List<Fighter> fighters) {
- System.out.println("Remove using index with errors");
- int countDeath = 0;
- printDeadAndlives(fighters);
- for (int i = 0; i < fighters.size(); i++) {
- if (!fighters.get(i).isAlive()) {
- countDeath++;
- fighters.remove(i);
- }
- }
- printDeadAndlives(fighters);
- return countDeath;
- }
-
- private static int removeDeadsUsingIndex(List<Fighter> fighters) {
- System.out.println("Remove using index");
- int countDeath = 0;
- printDeadAndlives(fighters);
- for (int i = fighters.size() - 1; i >= 0; i--) {
- if (!fighters.get(i).isAlive()) {
- countDeath++;
- fighters.remove(i);
- }
- }
- printDeadAndlives(fighters);
- return countDeath;
- }
-
- private static int removeDeadsUsingIterator(List<Fighter> fighters) {
- System.out.println("Remove using Iterator");
- printDeadAndlives(fighters);
- int countDeath = 0;
- Iterator<Fighter> iterator = fighters.iterator();
- while (iterator.hasNext()) {
- if (!iterator.next().isAlive()) {
- iterator.remove();
- countDeath++;
- }
- }
- printDeadAndlives(fighters);
- return countDeath;
- }
-
- private static void calculateAverageStrenght(List<Fighter> fighters) {
- int sumStrenght = 0;
- for (Fighter fighter : fighters) {
- sumStrenght += fighter.getStrenght();
- }
- System.out.println("Average strenght of all fighters is " + sumStrenght / fighters.size());
- int sumStrenghtOfHeroes = 0;
- int numberOfHeroes = 0;
- int sumStrenghtOfMonsters = 0;
- int numberOfMonsters = 0;
- for (Fighter fighter : fighters) {
- if (fighter instanceof Monster) {
- sumStrenghtOfMonsters += fighter.getStrenght();
- numberOfMonsters++;
- } else if (fighter instanceof Hero) {
- sumStrenghtOfHeroes += fighter.getStrenght();
- numberOfHeroes++;
- }
-
- }
- System.out.println("Average strenght of all Heros is " + sumStrenghtOfHeroes / numberOfHeroes);
- System.out.println("Average strenght of all Monsters is " + sumStrenghtOfMonsters / numberOfMonsters);
- }
-
- private static void calculateAverageLives(List<Fighter> fighters) {
- int sumLives = 0;
- for (Fighter fighter : fighters) {
- sumLives += fighter.getLives();
- }
- System.out.println("Average lives of all fighters is " + sumLives / fighters.size());
- int sumLivesOfHeroes = 0;
- int numberOfHeroes = 0;
- int sumLivesOfMonsters = 0;
- int numberOfMonsters = 0;
- for (Fighter fighter : fighters) {
- if (fighter instanceof Monster) {
- sumLivesOfMonsters += fighter.getLives();
- numberOfMonsters++;
- } else if (fighter instanceof Hero) {
- sumLivesOfHeroes += fighter.getLives();
- numberOfHeroes++;
- }
-
- }
- System.out.println("Average strenght of all Heros is " + sumLivesOfHeroes / numberOfHeroes);
- System.out.println("Average strenght of all Monsters is " + sumLivesOfMonsters / numberOfMonsters);
- }
-
- private static void printDeadAndlives(List<Fighter> fighters) {
- for (Fighter fighter : fighters) {
- System.out.print(fighter.isAlive()?"a":"D");
- }
- System.out.println();
- }
-
- private static void countFrequencyOfNames(List<Fighter> fighters, Map<String, Integer> namesCountMap) {
- for (Fighter fighter : fighters) {
- if (namesCountMap.containsKey(fighter.getName())) {
- Integer count = namesCountMap.get(fighter.getName());
- int newCount = count + 1;
- namesCountMap.put(fighter.getName(), newCount);
- } else {
- namesCountMap.put(fighter.getName(), 1);
- }
- }
- }
-
- private static void printOutAllNamesAndTheirCount(Map<String, Integer> namesCountMap) {
- for (String name1 : namesCountMap.keySet()) {
- int count = namesCountMap.get(name1);
- System.out.println(name1 + ": " + count);
- }
- }
-
-}
diff --git a/src/main/java/cz/vsb/fei/efrei/lab03/AlreadyDeadException.java b/src/main/java/cz/vsb/fei/efrei/lab04/AlreadyDeadException.java
similarity index 90%
rename from src/main/java/cz/vsb/fei/efrei/lab03/AlreadyDeadException.java
rename to src/main/java/cz/vsb/fei/efrei/lab04/AlreadyDeadException.java
index dd46d7a..ce09589 100644
--- a/src/main/java/cz/vsb/fei/efrei/lab03/AlreadyDeadException.java
+++ b/src/main/java/cz/vsb/fei/efrei/lab04/AlreadyDeadException.java
@@ -1,4 +1,4 @@
-package cz.vsb.fei.efrei.lab03;
+package cz.vsb.fei.efrei.lab04;
public class AlreadyDeadException extends Exception {
diff --git a/src/main/java/cz/vsb/fei/efrei/lab03/Fighter.java b/src/main/java/cz/vsb/fei/efrei/lab04/Fighter.java
similarity index 88%
rename from src/main/java/cz/vsb/fei/efrei/lab03/Fighter.java
rename to src/main/java/cz/vsb/fei/efrei/lab04/Fighter.java
index 442d9c9..f5b13d2 100644
--- a/src/main/java/cz/vsb/fei/efrei/lab03/Fighter.java
+++ b/src/main/java/cz/vsb/fei/efrei/lab04/Fighter.java
@@ -1,4 +1,4 @@
-package cz.vsb.fei.efrei.lab03;
+package cz.vsb.fei.efrei.lab04;
public interface Fighter {
diff --git a/src/main/java/cz/vsb/fei/efrei/lab03/Hero.java b/src/main/java/cz/vsb/fei/efrei/lab04/Hero.java
similarity index 83%
rename from src/main/java/cz/vsb/fei/efrei/lab03/Hero.java
rename to src/main/java/cz/vsb/fei/efrei/lab04/Hero.java
index d0d09a3..09bb8bf 100644
--- a/src/main/java/cz/vsb/fei/efrei/lab03/Hero.java
+++ b/src/main/java/cz/vsb/fei/efrei/lab04/Hero.java
@@ -1,13 +1,14 @@
-package cz.vsb.fei.efrei.lab03;
+package cz.vsb.fei.efrei.lab04;
+import java.util.Objects;
import java.util.Random;
public class Hero implements Fighter{
private static final Random RANDOM = new Random();
- private String name;
- private int strenght;
+ protected String name;
+ protected int strenght;
private int lives;
public Hero(String name, int strenght) {
@@ -22,7 +23,7 @@ public class Hero implements Fighter{
}
public Hero(String name) {
- this(name, RANDOM.nextInt(50) + 50);
+ this(name, RANDOM.nextInt(5000) + 50);
}
@Override
@@ -56,7 +57,7 @@ public class Hero implements Fighter{
@Override
public String toString() {
- return "Hero " + name + "(" + strenght + ") - has " + lives + " lives.";
+ return "Hero " + name + "(" + strenght + ")";
}
}
diff --git a/src/main/java/cz/vsb/fei/efrei/lab04/HeroWithEquals.java b/src/main/java/cz/vsb/fei/efrei/lab04/HeroWithEquals.java
new file mode 100644
index 0000000..61aa3b7
--- /dev/null
+++ b/src/main/java/cz/vsb/fei/efrei/lab04/HeroWithEquals.java
@@ -0,0 +1,27 @@
+package cz.vsb.fei.efrei.lab04;
+
+import java.util.Objects;
+
+public class HeroWithEquals extends Hero {
+
+ public HeroWithEquals(String name) {
+ super(name);
+ }
+
+ public HeroWithEquals(String name, int strenght) {
+ super(name, strenght);
+ }
+
+ @Override
+ public boolean equals(Object obj) {
+ if (this == obj)
+ return true;
+ if (obj == null)
+ return false;
+ if (getClass() != obj.getClass())
+ return false;
+ Hero other = (Hero) obj;
+ return Objects.equals(name, other.name);
+ }
+
+}
diff --git a/src/main/java/cz/vsb/fei/efrei/lab04/HeroWithEqualsAndBadHashcode.java b/src/main/java/cz/vsb/fei/efrei/lab04/HeroWithEqualsAndBadHashcode.java
new file mode 100644
index 0000000..a828729
--- /dev/null
+++ b/src/main/java/cz/vsb/fei/efrei/lab04/HeroWithEqualsAndBadHashcode.java
@@ -0,0 +1,32 @@
+package cz.vsb.fei.efrei.lab04;
+
+import java.util.Objects;
+
+public class HeroWithEqualsAndBadHashcode extends Hero {
+
+ public HeroWithEqualsAndBadHashcode(String name) {
+ super(name);
+ }
+
+ public HeroWithEqualsAndBadHashcode(String name, int strenght) {
+ super(name, strenght);
+ }
+
+ @Override
+ public int hashCode() {
+ return Objects.hash(strenght);
+ }
+
+ @Override
+ public boolean equals(Object obj) {
+ if (this == obj)
+ return true;
+ if (obj == null)
+ return false;
+ if (getClass() != obj.getClass())
+ return false;
+ Hero other = (Hero) obj;
+ return Objects.equals(name, other.name) && strenght == other.strenght;
+ }
+
+}
diff --git a/src/main/java/cz/vsb/fei/efrei/lab04/HeroWithEqualsAndConstantHashcode.java b/src/main/java/cz/vsb/fei/efrei/lab04/HeroWithEqualsAndConstantHashcode.java
new file mode 100644
index 0000000..c73a9ce
--- /dev/null
+++ b/src/main/java/cz/vsb/fei/efrei/lab04/HeroWithEqualsAndConstantHashcode.java
@@ -0,0 +1,32 @@
+package cz.vsb.fei.efrei.lab04;
+
+import java.util.Objects;
+
+public class HeroWithEqualsAndConstantHashcode extends Hero {
+
+ public HeroWithEqualsAndConstantHashcode(String name) {
+ super(name);
+ }
+
+ public HeroWithEqualsAndConstantHashcode(String name, int strenght) {
+ super(name, strenght);
+ }
+
+ @Override
+ public int hashCode() {
+ return 1;
+ }
+
+ @Override
+ public boolean equals(Object obj) {
+ if (this == obj)
+ return true;
+ if (obj == null)
+ return false;
+ if (getClass() != obj.getClass())
+ return false;
+ Hero other = (Hero) obj;
+ return Objects.equals(name, other.name) && strenght == other.strenght;
+ }
+
+}
diff --git a/src/main/java/cz/vsb/fei/efrei/lab04/HeroWithEqualsAndHashcode.java b/src/main/java/cz/vsb/fei/efrei/lab04/HeroWithEqualsAndHashcode.java
new file mode 100644
index 0000000..11d43f9
--- /dev/null
+++ b/src/main/java/cz/vsb/fei/efrei/lab04/HeroWithEqualsAndHashcode.java
@@ -0,0 +1,32 @@
+package cz.vsb.fei.efrei.lab04;
+
+import java.util.Objects;
+
+public class HeroWithEqualsAndHashcode extends Hero {
+
+ public HeroWithEqualsAndHashcode(String name) {
+ super(name);
+ }
+
+ public HeroWithEqualsAndHashcode(String name, int strenght) {
+ super(name, strenght);
+ }
+
+ @Override
+ public int hashCode() {
+ return Objects.hash(name, strenght);
+ }
+
+ @Override
+ public boolean equals(Object obj) {
+ if (this == obj)
+ return true;
+ if (obj == null)
+ return false;
+ if (getClass() != obj.getClass())
+ return false;
+ Hero other = (Hero) obj;
+ return Objects.equals(name, other.name) && strenght == other.strenght;
+ }
+
+}
diff --git a/src/main/java/cz/vsb/fei/efrei/lab03/Monster.java b/src/main/java/cz/vsb/fei/efrei/lab04/Monster.java
similarity index 97%
rename from src/main/java/cz/vsb/fei/efrei/lab03/Monster.java
rename to src/main/java/cz/vsb/fei/efrei/lab04/Monster.java
index 2817aa6..7b2edf0 100644
--- a/src/main/java/cz/vsb/fei/efrei/lab03/Monster.java
+++ b/src/main/java/cz/vsb/fei/efrei/lab04/Monster.java
@@ -1,4 +1,4 @@
-package cz.vsb.fei.efrei.lab03;
+package cz.vsb.fei.efrei.lab04;
import java.util.Random;
diff --git a/src/main/java/cz/vsb/fei/efrei/lab04/Stopwatch.java b/src/main/java/cz/vsb/fei/efrei/lab04/Stopwatch.java
new file mode 100644
index 0000000..a3e651f
--- /dev/null
+++ b/src/main/java/cz/vsb/fei/efrei/lab04/Stopwatch.java
@@ -0,0 +1,34 @@
+package cz.vsb.fei.efrei.lab04;
+
+public class Stopwatch {
+
+ private long startTime;
+ private long endTime;
+
+ public void start() {
+ startTime = System.nanoTime();
+ }
+
+ public void stop() {
+ endTime = System.nanoTime();
+ }
+
+ public long getDuration() {
+ return endTime - startTime;
+ }
+
+ public String formatDuration() {
+ long timeDuration = getDuration();
+ long timeNanoSec = timeDuration % 1000;
+ timeDuration = timeDuration / 1000;
+ long timeMicroSec = timeDuration % 1000;
+ timeDuration = timeDuration / 1000;
+ long timeMiliSec = timeDuration % 1000;
+ timeDuration = timeDuration / 1000;
+ long timeSec = timeDuration % 60;
+ timeDuration = timeDuration / 60;
+ long timeMinutes = timeDuration;
+ return String.format("%2dmin %2ds %3dms %3dus %3dns", timeMinutes, timeSec, timeMiliSec, timeMicroSec,
+ timeNanoSec);
+ }
+}
diff --git a/src/main/java/cz/vsb/fei/efrei/lab03/Utils.java b/src/main/java/cz/vsb/fei/efrei/lab04/Utils.java
similarity index 97%
rename from src/main/java/cz/vsb/fei/efrei/lab03/Utils.java
rename to src/main/java/cz/vsb/fei/efrei/lab04/Utils.java
index 7aba91a..3ab90ed 100644
--- a/src/main/java/cz/vsb/fei/efrei/lab03/Utils.java
+++ b/src/main/java/cz/vsb/fei/efrei/lab04/Utils.java
@@ -1,4 +1,4 @@
-package cz.vsb.fei.efrei.lab03;
+package cz.vsb.fei.efrei.lab04;
import java.util.Arrays;
import java.util.List;
diff --git a/src/main/java/cz/vsb/fei/efrei/lab04/WorldOfCollections.java b/src/main/java/cz/vsb/fei/efrei/lab04/WorldOfCollections.java
new file mode 100644
index 0000000..f33777d
--- /dev/null
+++ b/src/main/java/cz/vsb/fei/efrei/lab04/WorldOfCollections.java
@@ -0,0 +1,177 @@
+package cz.vsb.fei.efrei.lab04;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.HashSet;
+import java.util.LinkedList;
+import java.util.List;
+import java.util.Random;
+import java.util.Set;
+
+public class WorldOfCollections {
+ private static final Random RANDOM = new Random();
+
+ public static void main(String[] args) {
+ useSetToStoreObjectWithoutHashCodeAndEquals();
+ useSetToStoreObjectWithEqualsOnlyForName();
+ useSetToStoreObjectWithEqualsAndHashCode();
+ useSetToStoreObjectWithEqualsBasedOnNameAndBadHashCode();
+ useSetToStoreObjectWithEqualsAndConstantHashCode();
+ System.out.println("==========================================================================================");
+ performanceForUseSetToStoreObjectWithEqualsAndHashCode();
+ performanceForUseSetToStoreObjectWithEqualsAndConstantHashCode();
+ System.out.println("==========================================================================================");
+ performanceForAddIntoArrayList();
+ performanceForAddIntoLinkedList();
+ performanceForInsertIntoArrayList();
+ performanceForInsertIntoLinkedList();
+
+ }
+
+ private static void testObjectAnHashSet(Set<Fighter> setOfFighters, Hero king1, Hero king2) {
+ setOfFighters.add(king1);
+ System.out.println("Is king1 " + king1 + " in set: " + setOfFighters.contains(king1));
+ System.out.println("Is king1 " + king1 + " equal to king2 " + king2 + ": " + king1.equals(king2));
+ System.out.println("Is king2 in set: " + setOfFighters.contains(king2));
+ setOfFighters.add(king2);
+ System.out.println("Is king2 in set after add: " + setOfFighters.contains(king2));
+ System.out.println("Size of set is: " + setOfFighters.size());
+ }
+
+ public static void useSetToStoreObjectWithoutHashCodeAndEquals() {
+ Set<Fighter> setOfFighters = new HashSet<>();
+ Hero king1 = new Hero("King", 66);
+ Hero king2 = new Hero("King", 66);
+ System.out.println("=====Use HashSet to Store Object Without HashCode And Equals================================");
+ testObjectAnHashSet(setOfFighters, king1, king2);
+ System.out.println("Each object is different (different palces in memory) even look same!");
+ }
+
+
+ public static void useSetToStoreObjectWithEqualsOnlyForName() {
+ Set<Fighter> setOfFighters = new HashSet<>();
+ Hero king1 = new HeroWithEquals("King", 66);
+ Hero king2 = new HeroWithEquals("King", 42);
+ System.out.println("=====Use HashSet to Store Object Only With Equals================================");
+ testObjectAnHashSet(setOfFighters, king1, king2);
+ System.out.println("Object are equals because of same name, but not found in set because of worng hashcode!");
+ }
+
+ public static void useSetToStoreObjectWithEqualsAndHashCode() {
+ Set<Fighter> setOfFighters = new HashSet<>();
+ Hero king1 = new HeroWithEqualsAndHashcode("King", 66);
+ Hero king2 = new HeroWithEqualsAndHashcode("King", 66);
+ System.out.println("=====Use HashSet to Store Object Only With Equals================================");
+ testObjectAnHashSet(setOfFighters, king1, king2);
+ System.out.println("It's work!");
+ }
+
+ public static void useSetToStoreObjectWithEqualsBasedOnNameAndBadHashCode() {
+ Set<Fighter> setOfFighters = new HashSet<>();
+ Hero king1 = new HeroWithEqualsAndBadHashcode("King", 66);
+ Hero king2 = new HeroWithEqualsAndBadHashcode("King", 42);
+ System.out.println("=====Use HashSet to Store Object With Equals and BAD hashcode================================");
+ testObjectAnHashSet(setOfFighters, king1, king2);
+ System.out.println("It does'n work!");
+ System.out.println("Object are equals because of same name, but not found in set because of worng hashcode calculated from strenght!");
+ }
+
+ public static void useSetToStoreObjectWithEqualsAndConstantHashCode() {
+ Set<Fighter> setOfFighters = new HashSet<>();
+ Hero king1 = new HeroWithEqualsAndConstantHashcode("King", 66);
+ Hero king2 = new HeroWithEqualsAndConstantHashcode("King", 66);
+ System.out.println("=====Use HashSet to Store Object With Equals and constant hashcode================================");
+ testObjectAnHashSet(setOfFighters, king1, king2);
+ System.out.println("It's work!");
+ }
+
+ private static String mesureAndAdd(Collection<Hero> sourceOfHeros, Collection<Hero> tragetOfHeros) {
+ Stopwatch stopwatch = new Stopwatch();
+ stopwatch.start();
+ for (Hero hero : sourceOfHeros) {
+ tragetOfHeros.add(hero);
+ }
+ stopwatch.stop();
+ String duration = stopwatch.formatDuration();
+ return duration;
+ }
+
+ private static String mesureAndInsert(Collection<Hero> sourceOfHeros, List<Hero> tragetOfHeros) {
+ Stopwatch stopwatch = new Stopwatch();
+ stopwatch.start();
+ for (Hero hero : sourceOfHeros) {
+ tragetOfHeros.add(0, hero);
+ }
+ stopwatch.stop();
+ String duration = stopwatch.formatDuration();
+ return duration;
+ }
+
+ public static void performanceForUseSetToStoreObjectWithEqualsAndHashCode() {
+ int countOfHeros = 20000;
+ List<Hero> heros = new ArrayList<>(countOfHeros);
+ for (int i = 0; i < countOfHeros; i++) {
+ heros.add(new HeroWithEqualsAndHashcode(Utils.generateHeroName()));
+ }
+ Set<Hero> setOfHeros = new HashSet<>();
+ String duration = mesureAndAdd(heros, setOfHeros);
+ System.out.println("Adding " + countOfHeros + " heros with correct hashcode and equals into set take " + duration);
+ }
+
+
+ public static void performanceForUseSetToStoreObjectWithEqualsAndConstantHashCode() {
+ int countOfHeros = 20000;
+ List<Hero> heros = new ArrayList<>(countOfHeros);
+ for (int i = 0; i < countOfHeros; i++) {
+ heros.add(new HeroWithEqualsAndConstantHashcode(Utils.generateHeroName()));
+ }
+ Set<Hero> setOfHeros = new HashSet<>();
+ String duration = mesureAndAdd(heros, setOfHeros);
+ System.out.println("Adding " + countOfHeros + " heros with constant hashcode into set take " + duration);
+ }
+
+
+ public static void performanceForAddIntoArrayList() {
+ int countOfHeros = 500000;
+ List<Hero> heros = new ArrayList<>(countOfHeros);
+ for (int i = 0; i < countOfHeros; i++) {
+ heros.add(new HeroWithEqualsAndConstantHashcode(Utils.generateHeroName()));
+ }
+ List<Hero> arrayListOfHeros = new ArrayList<>();
+ String duration = mesureAndAdd(heros, arrayListOfHeros);
+ System.out.println("Adding " + countOfHeros + " heros to end of ArrayList take " + duration);
+ }
+
+ public static void performanceForAddIntoLinkedList() {
+ int countOfHeros = 500000;
+ List<Hero> heros = new ArrayList<>(countOfHeros);
+ for (int i = 0; i < countOfHeros; i++) {
+ heros.add(new HeroWithEqualsAndConstantHashcode(Utils.generateHeroName()));
+ }
+ List<Hero> arrayListOfHeros = new LinkedList<>();
+ String duration = mesureAndAdd(heros, arrayListOfHeros);
+ System.out.println("Adding " + countOfHeros + " heros to end of LinkedList take " + duration);
+ }
+
+ public static void performanceForInsertIntoArrayList() {
+ int countOfHeros = 500000;
+ List<Hero> heros = new ArrayList<>(countOfHeros);
+ for (int i = 0; i < countOfHeros; i++) {
+ heros.add(new HeroWithEqualsAndConstantHashcode(Utils.generateHeroName()));
+ }
+ List<Hero> arrayListOfHeros = new ArrayList<>();
+ String duration = mesureAndInsert(heros, arrayListOfHeros);
+ System.out.println("Inserting " + countOfHeros + " heros at beginnig of ArrayList take " + duration);
+ }
+
+ public static void performanceForInsertIntoLinkedList() {
+ int countOfHeros = 500000;
+ List<Hero> heros = new ArrayList<>(countOfHeros);
+ for (int i = 0; i < countOfHeros; i++) {
+ heros.add(new HeroWithEqualsAndConstantHashcode(Utils.generateHeroName()));
+ }
+ List<Hero> arrayListOfHeros = new LinkedList<>();
+ String duration = mesureAndInsert(heros, arrayListOfHeros);
+ System.out.println("Inserting " + countOfHeros + " heros at beginnig of LinkedList take " + duration);
+ }
+}
--
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