Enhance trigger interface to allow merging states.

[rhynodge.git] / src / main / java / net / pterodactylus / rhynodge / Trigger.java

diff --git a/src/main/java/net/pterodactylus/rhynodge/Trigger.java b/src/main/java/net/pterodactylus/rhynodge/Trigger.java
index 3b5a730..e4024f2 100644 (file)
--- a/src/main/java/net/pterodactylus/rhynodge/Trigger.java
+++ b/src/main/java/net/pterodactylus/rhynodge/Trigger.java
@@ -31,20 +31,31 @@ import net.pterodactylus.rhynodge.states.FileState;
 public interface Trigger {
 
        /**
-        * Checks whether the given states warrant a change trigger.
+        * Merges the current state into the previous state, returning the merged
+        * state.
         *
-        * @param currentState
-        *            The current state of a system
         * @param previousState
         *            The previous state of the system
-        * @return {@code true} if the given states warrant a change trigger,
+        * @param currentState
+        *            The current state of a system
+        * @return The new state, containing a meaningful merge between the previous
+        *         and the current state
+        */
+       State mergeStates(State previousState, State currentState);
+
+       /**
+        * Checks whether the states given to {@link #mergeStates(State, State)}
+        * warrant a change trigger.
+        *
+        * @return {@code true} if the states given to
+        *         {@link #mergeStates(State, State)} warrant a change trigger,
         *         {@code false} otherwise
         */
-       boolean triggers(State currentState, State previousState);
+       boolean triggers();
 
        /**
         * Returns the output of this trigger. This will only return a meaningful
-        * value if {@link #triggers(State, State)} returns {@code true}.
+        * value if {@link #triggers()} returns {@code true}.
         *
         * @param reaction
         *            The reaction being triggered