11b - inheritance and Object

materials/2024-2025/11b/2024-11-04-object-class/.gitignore

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+### IntelliJ IDEA ###
+out/
+!**/src/main/**/out/
+!**/src/test/**/out/
+
+### Eclipse ###
+.apt_generated
+.classpath
+.factorypath
+.project
+.settings
+.springBeans
+.sts4-cache
+bin/
+!**/src/main/**/bin/
+!**/src/test/**/bin/
+
+### NetBeans ###
+/nbproject/private/
+/nbbuild/
+/dist/
+/nbdist/
+/.nb-gradle/
+
+### VS Code ###
+.vscode/
+
+### Mac OS ###
+.DS_Store

materials/2024-2025/11b/2024-11-04-object-class/2024-11-04-object-class.iml

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+<?xml version="1.0" encoding="UTF-8"?>
+<module type="JAVA_MODULE" version="4">
+  <component name="NewModuleRootManager" inherit-compiler-output="true">
+    <exclude-output />
+    <content url="file://$MODULE_DIR$">
+      <sourceFolder url="file://$MODULE_DIR$/src" isTestSource="false" />
+    </content>
+    <orderEntry type="inheritedJdk" />
+    <orderEntry type="sourceFolder" forTests="false" />
+  </component>
+</module>

materials/2024-2025/11b/2024-11-04-object-class/src/Main.java

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+import java.util.HashMap;
+import java.util.Map;
+import java.util.TreeMap;
+
+public class Main {
+    public static void main(String[] args) {
+        Object o1 = new Object();
+        Object o2 = new Object();
+
+        System.out.println(o1);
+        System.out.println(o2);
+        System.out.println(o1 == o2);
+        System.out.println(o1.equals(o2));
+        System.out.println(o1.toString());
+
+        Pastry p1 = new Pastry("Prava", false);
+        Pastry p2 = new Pastry("Sofiiska", true);
+        Pastry p3 = new Pastry("Prava", false);
+
+        System.out.println(p1);
+        System.out.println(p2);
+        System.out.println(p1 == p2);
+        System.out.println(p1.equals(p2));
+        System.out.println(p1.hashCode());
+        System.out.println(p2.hashCode());
+
+        System.out.println(p1 == p3);
+        System.out.println(p1.equals(p3));
+
+        Map<Pastry, Pastry> map1 = new HashMap<>();
+        map1.put(p1, p1);
+        map1.put(p2, p2);
+        map1.put(p3, p3);
+        System.out.println(map1);
+        System.out.println(map1.keySet());
+
+        Map<Pastry, Pastry> map2 = new TreeMap<>();
+        map2.put(p1, p1);
+        map2.put(p2, p2);
+        map2.put(p3, p3);
+        System.out.println(map2);
+        System.out.println(map2.keySet());
+    }
+}

materials/2024-2025/11b/2024-11-04-object-class/src/Pastry.java

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+import java.util.Objects;
+
+public class Pastry {
+    private String name;
+    private boolean hasCheese;
+
+    public Pastry(String name, boolean hasCheese) {
+        this.name = name;
+        this.hasCheese = hasCheese;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public boolean getHasCheese() {
+        return hasCheese;
+    }
+
+    @Override
+    public String toString() {
+        return "Pastry{" +
+                "name='" + name + '\'' +
+                ", hasCheese=" + hasCheese +
+                '}';
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) return true;
+        if (o == null || getClass() != o.getClass()) return false;
+        Pastry pastry = (Pastry) o;
+        return hasCheese == pastry.hasCheese &&
+//                Objects.equals(name, pastry.name);
+                name.equals(pastry.name);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(name, hasCheese);
+    }
+}