From 301f547f5d42a8a8605c4c515b44bfa1f0bd55bd Mon Sep 17 00:00:00 2001
From: Pawel Karczewski <pawel.karczewski@intel.com>
Date: Tue, 30 Jun 2020 19:06:06 +0200
Subject: [PATCH] Add javadoc and mark as FunctionalInterface callback
 interfaces

---
 src/main/java/io/pmem/pmemkv/KeyCallback.java | 15 ++++++++++++++-
 .../java/io/pmem/pmemkv/KeyValueCallback.java | 19 ++++++++++++++++++-
 .../java/io/pmem/pmemkv/ValueCallback.java    | 15 ++++++++++++++-
 3 files changed, 46 insertions(+), 3 deletions(-)

diff --git a/src/main/java/io/pmem/pmemkv/KeyCallback.java b/src/main/java/io/pmem/pmemkv/KeyCallback.java
index f0bc5309..b46283f7 100644
--- a/src/main/java/io/pmem/pmemkv/KeyCallback.java
+++ b/src/main/java/io/pmem/pmemkv/KeyCallback.java
@@ -3,8 +3,21 @@
 
 package io.pmem.pmemkv;
 
+/**
+ * Represents callback function, which handle value-only use cases. Such
+ * expression may be passed to get() method in Database class
+ *
+ * @param <KeyT>
+ *            the type of a key stored in the pmemkv database
+ */
+@FunctionalInterface
 public interface KeyCallback<KeyT> {
-
+	/**
+	 * It's internally used as a middle layer to run callback function
+	 *
+	 * @param key
+	 *            the key returned by pmemkv engine to callback function
+	 */
 	void process(KeyT key);
 
 }
diff --git a/src/main/java/io/pmem/pmemkv/KeyValueCallback.java b/src/main/java/io/pmem/pmemkv/KeyValueCallback.java
index 7af6e2e1..598fc077 100644
--- a/src/main/java/io/pmem/pmemkv/KeyValueCallback.java
+++ b/src/main/java/io/pmem/pmemkv/KeyValueCallback.java
@@ -3,8 +3,25 @@
 
 package io.pmem.pmemkv;
 
+/**
+ * Represents callback function, which handle value-only use cases. Such
+ * expression may be passed to get() method in Database class
+ *
+ * @param <KeyT>
+ *            the type of a key stored in the pmemkv database
+ * @param <ValueT>
+ *            the type of a value stored in the pmemkv database
+ */
+@FunctionalInterface
 public interface KeyValueCallback<KeyT, ValueT> {
-
+	/**
+	 * It's internally used as a middle layer to run callback function
+	 *
+	 * @param key
+	 *            the key returned by pmemkv engine to the callback function
+	 * @param value
+	 *            the value returned by pmemkv engine to the callback function
+	 */
 	void process(KeyT key, ValueT value);
 
 }
diff --git a/src/main/java/io/pmem/pmemkv/ValueCallback.java b/src/main/java/io/pmem/pmemkv/ValueCallback.java
index 4b85c264..b690fb70 100644
--- a/src/main/java/io/pmem/pmemkv/ValueCallback.java
+++ b/src/main/java/io/pmem/pmemkv/ValueCallback.java
@@ -3,8 +3,21 @@
 
 package io.pmem.pmemkv;
 
+/**
+ * Represents callback function, which handle value-only use cases. Such
+ * expression may be passed to get*() methods in Database class
+ *
+ * @param <ValueT>
+ *            the type of a key stored in the pmemkv database
+ */
+@FunctionalInterface
 public interface ValueCallback<ValueT> {
-
+	/**
+	 * It's internally used as a middle layer to run callback function
+	 *
+	 * @param value
+	 *            the value returned by pmemkv engine to the callback function
+	 */
 	void process(ValueT value);
 
 }