Updated javadocs for some of the internal cache classes - Fixes #3011.

Signed-off-by: Alexey Goncharuk <alexey.goncharuk@gmail.com>

modules/core/src/main/java/org/apache/ignite/internal/processors/cache/CacheGroupContext.java

@@ -673,7 +673,7 @@ public void onKernalStop() {
 
     /**
      * @param cctx Cache context.
-     * @param destroy Destroy flag.
+     * @param destroy Destroy data flag. Setting to <code>true</code> will remove all cache data.
      */
     void stopCache(GridCacheContext cctx, boolean destroy) {
         if (top != null)

modules/core/src/main/java/org/apache/ignite/internal/processors/cache/DynamicCacheChangeRequest.java

@@ -71,7 +71,7 @@ public class DynamicCacheChangeRequest implements Serializable {
     /** Cache active on start or not*/
     private boolean disabledAfterStart;
 
-    /** Destroy. */
+    /** Cache data destroy flag. Setting to <code>true</code> will cause removing all cache data.*/
     private boolean destroy;
 
     /** Whether cache was created through SQL. */
@@ -144,7 +144,7 @@ static DynamicCacheChangeRequest addTemplateRequest(GridKernalContext ctx, Cache
      * @param ctx Context.
      * @param cacheName Cache name.
      * @param sql {@code true} if the cache must be stopped only if it was created by SQL command {@code CREATE TABLE}.
-     * @param destroy Destroy flag.
+     * @param destroy Cache data destroy flag. Setting to <code>true</code> will cause removing all cache data.
      * @return Cache stop request.
      */
     public static DynamicCacheChangeRequest stopRequest(
@@ -226,14 +226,15 @@ public boolean stop() {
     }
 
     /**
-     * @return Destroy flag.
+     * @return Cache data destroy flag. Setting to <code>true</code> will remove all cache data.
      */
     public boolean destroy(){
         return destroy;
     }
 
     /**
-     * @param destroy Destroy.
+     * Sets cache data destroy flag. Setting to <code>true</code> will cause removing all cache data.
+     * @param destroy Destroy flag.
      */
     public void destroy(boolean destroy) {
         this.destroy = destroy;
@@ -359,6 +360,8 @@ public boolean sql() {
     }
 
     /**
+     * Sets if cache is created using create table.
+     *
      * @param sql New SQL flag.
      */
     public void sql(boolean sql) {

modules/core/src/main/java/org/apache/ignite/internal/processors/cache/GridCacheProcessor.java

@@ -1133,6 +1133,7 @@ private void startCache(GridCacheAdapter<?, ?> cache, QuerySchema schema) throws
     /**
      * @param cache Cache to stop.
      * @param cancel Cancel flag.
+     * @param destroy Destroy data flag. Setting to <code>true</code> will remove all cache data.
      */
     @SuppressWarnings({"TypeMayBeWeakened", "unchecked"})
     private void stopCache(GridCacheAdapter<?, ?> cache, boolean cancel, boolean destroy) {
@@ -1963,7 +1964,7 @@ private void stopGateway(DynamicCacheChangeRequest req) {
 
     /**
      * @param cacheName Cache name.
-     * @param destroy Cache destroy flag.
+     * @param destroy Cache data destroy flag. Setting to <code>true</code> will remove all cache data.
      * @return Stopped cache context.
      */
     private GridCacheContext<?, ?> prepareCacheStop(String cacheName, boolean destroy) {
@@ -2697,6 +2698,7 @@ else if (internalCaches.contains(ccfg.getName()))
      * @param sql If the cache needs to be destroyed only if it was created as the result of SQL {@code CREATE TABLE}
      * command.
      * @param checkThreadTx If {@code true} checks that current thread does not have active transactions.
+     * @param restart Restart flag.
      * @return Future that will be completed when cache is destroyed.
      */
     public IgniteInternalFuture<Boolean> dynamicDestroyCache(String cacheName, boolean sql, boolean checkThreadTx,
@@ -2718,6 +2720,7 @@ public IgniteInternalFuture<Boolean> dynamicDestroyCache(String cacheName, boole
     /**
      * @param cacheNames Collection of cache names to destroy.
      * @param checkThreadTx If {@code true} checks that current thread does not have active transactions.
+     * @param restart Restart flag.
      * @return Future that will be completed when cache is destroyed.
      */
     public IgniteInternalFuture<?> dynamicDestroyCaches(Collection<String> cacheNames, boolean checkThreadTx,
@@ -2728,6 +2731,8 @@ public IgniteInternalFuture<?> dynamicDestroyCaches(Collection<String> cacheName
     /**
      * @param cacheNames Collection of cache names to destroy.
      * @param checkThreadTx If {@code true} checks that current thread does not have active transactions.
+     * @param restart Restart flag.
+     * @param destroy Cache data destroy flag. Setting to <code>true</code> will cause removing all cache data
      * @return Future that will be completed when cache is destroyed.
      */
     public IgniteInternalFuture<?> dynamicDestroyCaches(Collection<String> cacheNames, boolean checkThreadTx,

modules/core/src/main/java/org/apache/ignite/internal/processors/cache/IgniteCacheOffheapManager.java

@@ -60,7 +60,7 @@ public interface IgniteCacheOffheapManager {
 
     /**
      * @param cacheId Cache ID.
-     * @param destroy Destroy data flag.
+     * @param destroy Destroy data flag. Setting to <code>true</code> will remove all cache data.
      */
     public void stopCache(int cacheId, boolean destroy);
 

modules/core/src/main/java/org/apache/ignite/internal/processors/cache/persistence/snapshot/SnapshotOperation.java

@@ -28,17 +28,18 @@ public interface SnapshotOperation extends Serializable {
     /**
      * Cache group ids included to this snapshot.
      *
-     * @return Cache names.
+     * @return Cache group identifiers.
      */
     public Set<Integer> cacheGroupIds();
 
     /**
-     * Cache names included to this snapshot.
+     * @return Cache names included to this snapshot.
      */
     public Set<String> cacheNames();
 
     /**
-     * Any custom extra parameter.
+     * @return Any custom extra parameter.
+     * In case Map object is provided, contains named snapshot operation attributes.
      */
     public Object extraParameter();
 }