Added missing class

library/src/main/java/org/hitogo/core/HitogoPrioritySubClass.java

@@ -0,0 +1,73 @@
+package org.hitogo.core;
+
+import java.util.HashSet;
+
+/**
+ * This class is used as an object to determine the different priority sub-classes that are
+ * currently active/not active. The result of the object will tell the system if the requested
+ * alert is allowed to be shown now or later.
+ *
+ * @since 1.0.0
+ */
+public class HitogoPrioritySubClass {
+
+    private int subClassPriority = Integer.MAX_VALUE;
+    private HashSet<Integer> subClassHashCodes = new HashSet<>();
+    private boolean isSubClassVisible;
+
+    /**
+     * Returns the priority that this sub-class is representing.
+     *
+     * @return an Int value
+     * @since 1.0.0
+     */
+    public int getSubClassPriority() {
+        return subClassPriority;
+    }
+
+    /**
+     * Sets the priority for this sub-class.
+     *
+     * @param subClassPriority an Int value
+     * @since 1.0.0
+     */
+    public void setSubClassPriority(int subClassPriority) {
+        this.subClassPriority = subClassPriority;
+    }
+
+    /**
+     * Returns if the given alert is allowed to be displayed. This is determined one the conditions
+     * if the sub-class has one visible alert already and if the given alert hashcode is part of
+     * this sub-class.
+     *
+     * @param alertHashCode an Int value
+     * @return True if the alert is allowed to be displayed, false otherwise.
+     * @since 1.0.0
+     */
+    public boolean isAlertVisibilityAllowed(int alertHashCode) {
+        return !isSubClassVisible && subClassHashCodes.contains(alertHashCode);
+    }
+
+    /**
+     * Adds an alert hashcode to this sub-class.
+     *
+     * @param alertHashCode an Int value
+     * @since 1.0.0
+     */
+    public void addSubClassAlertHashCode(int alertHashCode) {
+        this.subClassHashCodes.add(alertHashCode);
+    }
+
+    /**
+     * Sets the sub-class visibility which is true if one alert in this sub-class is visible to
+     * the user.
+     *
+     * @param subClassVisible a boolean value
+     * @since 1.0.0
+     */
+    public void setSubClassVisible(boolean subClassVisible) {
+        if (subClassVisible) {
+            isSubClassVisible = true;
+        }
+    }
+}