Improved documentation

src/main/java/net/openhft/chronicle/set/SetAbsentEntry.java

@@ -2,9 +2,28 @@ package net.openhft.chronicle.set;
 
 import net.openhft.chronicle.hash.HashAbsentEntry;
 
+/**
+ * Low-level operational context for the situations, when the new key is going to be inserted
+ * into the {@link ChronicleSet}.
+ *
+ * @param <K> the set key type
+ *
+ * @see SetEntryOperations
+ * @see SetQueryContext#absentEntry()
+ */
 public interface SetAbsentEntry<K> extends HashAbsentEntry<K> {
     @Override
     SetContext<K, ?> context();
-    
+
+    /**
+     * Inserts {@link #absentKey() the new key} into the set.
+     *
+     * <p>This method is the default implementation for {@link SetEntryOperations#insert(
+     * SetAbsentEntry)}, which might be customized over the default.
+     *
+     * @throws IllegalStateException if some locking/state conditions required to perform insertion
+     * operation are not met
+     * @see SetEntryOperations#insert(SetAbsentEntry)
+     */
     void doInsert();
 }