diff --git a/src/main/java/io/github/auberonedu/equalsLivecode/App.java b/src/main/java/io/github/auberonedu/equalsLivecode/App.java index 53efd3e..d2d978d 100644 --- a/src/main/java/io/github/auberonedu/equalsLivecode/App.java +++ b/src/main/java/io/github/auberonedu/equalsLivecode/App.java @@ -14,13 +14,33 @@ public static void main(String[] args) { Centroid locA = new Centroid(4, 9, "Salamander"); Centroid locB = new Centroid(4, 9, "Salamander"); - System.out.println("Result of locA == locB " + (locA == locB)); - System.out.println("Result of locA.equals(locB) " + locA.equals(locB)); + System.out.println("Result of locA == locB " + (locA == locB)); // comparing reference + System.out.println("Result of locA.equals(locB) " + locA.equals(locB)); // hopefully value equality (if rewritten in Centroid.java) - videoDemo(); + Set centroids = new HashSet<>(); + centroids.add(locA); + centroids.add(locB); + + System.out.println(locA.hashCode()); + System.out.println(locB.hashCode()); + + System.out.println(centroids.contains(locB)); + + + System.out.println("--- Records ---"); + Location a = new Location(5, 1, "food"); + Location b = new Location(5, 1, "food"); + + System.out.println(a.equals(b)); + System.out.println(a.hashCode()); + System.out.println(b.hashCode()); + + + //videoDemo(); } // We will look at this a bit later in the livecode, please ignore for first part + public static void videoDemo() { List video = List.of( // Frame 0: Salamander is at [2, 3] (all locations in [row, column] format) @@ -94,5 +114,5 @@ public static void videoDemo() { boolean hasOverlap = !Collections.disjoint(salamanderLocations, foodLocations); System.out.println("Do the salamander locations overlap with the food locations: " + hasOverlap); } - + } diff --git a/src/main/java/io/github/auberonedu/equalsLivecode/Centroid.java b/src/main/java/io/github/auberonedu/equalsLivecode/Centroid.java index b0e343a..f772956 100644 --- a/src/main/java/io/github/auberonedu/equalsLivecode/Centroid.java +++ b/src/main/java/io/github/auberonedu/equalsLivecode/Centroid.java @@ -22,4 +22,57 @@ public int getC() { public String getName() { return name; } + + @Override + public int hashCode() { + final int prime = 31; + int result = 1; + result = prime * result + r; + result = prime * result + c; + result = prime * result + ((name == null) ? 0 : name.hashCode()); + return result; + } + + @Override + public boolean equals(Object obj) { + if (this == obj) + return true; + if (obj == null) + return false; + if (getClass() != obj.getClass()) + return false; + Centroid other = (Centroid) obj; + if (r != other.r) + return false; + if (c != other.c) + return false; + if (name == null) { + if (other.name != null) + return false; + } else if (!name.equals(other.name)) + return false; + return true; + } + + + // @Override + // // allowed to access private fields of different objects in the same class + // public boolean equals(Object o) { + // if (o == null) return false; // checking if o is null -- false + // if (getClass() != o.getClass()) return false; // checking if o is not a Centroid -- false + + // Centroid other = (Centroid) o; // casting o as a Centroid + + // // compare fields + // if(r != other.r) return false; + // if(c != other.c) return false; + // if(name == null){ + // if (other.name == null) return true; + // if (other.name != null) return false; + // } + // if(!name.equals(other.name)) return false; + + // return true; + + // } } diff --git a/src/main/java/io/github/auberonedu/equalsLivecode/Location.java b/src/main/java/io/github/auberonedu/equalsLivecode/Location.java new file mode 100644 index 0000000..b5ec455 --- /dev/null +++ b/src/main/java/io/github/auberonedu/equalsLivecode/Location.java @@ -0,0 +1,4 @@ +package io.github.auberonedu.equalsLivecode; + +public record Location(int x, int y, String label) { +}