Implement Pair.java util for referencing 2 objects + hashing

main/src/main/java/org/minerift/ether/util/pair/Pair.java

@@ -0,0 +1,41 @@
+package org.minerift.ether.util.pair;
+
+import com.google.common.base.Objects;
+import com.google.common.base.Preconditions;
+
+public class Pair<F, S> {
+
+    protected final F first;
+    protected final S second;
+
+    public Pair(F first, S second) {
+        this.first = first;
+        this.second = second;
+    }
+
+    public Pair(Object[] pair) {
+        Preconditions.checkArgument(pair.length == 2, "Must only be 2 elements in pair!");
+        this.first = (F) pair[0];
+        this.second = (S) pair[1];
+    }
+
+    public F getFirst() {
+        return first;
+    }
+
+    public S getSecond() {
+        return second;
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) return true;
+        if (!(o instanceof Pair<?, ?> pair)) return false;
+        return Objects.equal(first, pair.first) && Objects.equal(second, pair.second);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hashCode(first, second);
+    }
+}

main/src/main/java/org/minerift/ether/util/pair/SameTypePair.java

@@ -0,0 +1,30 @@
+package org.minerift.ether.util.pair;
+
+import java.lang.reflect.Array;
+import java.util.function.IntFunction;
+
+public class SameTypePair<T> extends Pair<T, T> {
+
+    public SameTypePair(T first, T second) {
+        super(first, second);
+    }
+
+    public SameTypePair(T[] pair) {
+        super(pair);
+    }
+
+    private T[] fillArray(T[] emptyArray) {
+        emptyArray[0] = first;
+        emptyArray[1] = second;
+        return emptyArray;
+    }
+
+    public T[] toArray(Class<T> clazz) {
+        return fillArray((T[]) Array.newInstance(clazz, 2));
+    }
+
+    // Preferred method override
+    public T[] toArray(IntFunction<T[]> arrayCreator) {
+        return fillArray(arrayCreator.apply(2));
+    }
+}

main/src/main/java/org/minerift/ether/util/pair/UUIDPair.java

@@ -0,0 +1,17 @@
+package org.minerift.ether.util.pair;
+
+import java.util.UUID;
+
+public class UUIDPair extends SameTypePair<UUID> {
+    public UUIDPair(UUID first, UUID second) {
+        super(first, second);
+    }
+
+    public UUIDPair(UUID[] pair) {
+        super(pair);
+    }
+
+    public UUID[] toArray() {
+        return toArray(UUID[]::new);
+    }
+}