[Bleeding] Added Conversations API. Addresses BUKKIT-864

src/main/java/org/bukkit/conversations/Prompt.java

@@ -0,0 +1,36 @@
+package org.bukkit.conversations;
+
+/**
+ * A Prompt is the main constituent of a {@link Conversation}. Each prompt displays text to the user and optionally
+ * waits for a user's response. Prompts are chained together into a directed graph that represents the conversation
+ * flow. To halt a conversation, END_OF_CONVERSATION is returned in liu of another Prompt object.
+ */
+public interface Prompt extends Cloneable {
+
+    /**
+     * A convenience constant for indicating the end of a conversation.
+     */
+    static final Prompt END_OF_CONVERSATION = null;
+
+    /**
+     * Gets the text to display to the user when this prompt is first presented.
+     * @param context Context information about the conversation.
+     * @return The text to display.
+     */
+    String getPromptText(ConversationContext context);
+
+    /**
+     * Checks to see if this prompt implementation should wait for user input or immediately display the next prompt.
+     * @param context Context information about the conversation.
+     * @return If true, the {@link Conversation} will wait for input before continuing.
+     */
+    boolean blocksForInput(ConversationContext context);
+
+    /**
+     * Accepts and processes input from the user. Using the input, the next Prompt in the prompt graph is returned.
+     * @param context Context information about the conversation.
+     * @param input The input text from the user.
+     * @return The next Prompt in the prompt graph.
+     */
+    Prompt acceptInput(ConversationContext context, String input);
+}