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Diffstat (limited to 'documentation/sqlcontainer/sqlcontainer-nonimplemented.asciidoc')
| -rw-r--r-- | documentation/sqlcontainer/sqlcontainer-nonimplemented.asciidoc | 66 |
1 files changed, 0 insertions, 66 deletions
diff --git a/documentation/sqlcontainer/sqlcontainer-nonimplemented.asciidoc b/documentation/sqlcontainer/sqlcontainer-nonimplemented.asciidoc deleted file mode 100644 index 595085822f..0000000000 --- a/documentation/sqlcontainer/sqlcontainer-nonimplemented.asciidoc +++ /dev/null @@ -1,66 +0,0 @@ ---- -title: Non-Implemented Methods -order: 8 -layout: page ---- - -[[sqlcontainer.nonimplemented]] -= Non-Implemented Methods - -Due to the database connection inherent to the SQLContainer, some of the methods -from the container interfaces of Vaadin can not (or would not make sense to) be -implemented. These methods are listed below, and they will throw an -[classname]#UnsupportedOperationException# on invocation. - - ----- -public boolean addContainerProperty(Object propertyId, - Class<?> type, - Object defaultValue) -public boolean removeContainerProperty(Object propertyId) -public Item addItem(Object itemId) -public Object addItemAt(int index) -public Item addItemAt(int index, Object newItemId) -public Object addItemAfter(Object previousItemId) -public Item addItemAfter(Object previousItemId, Object newItemId) ----- - -Additionally, the following methods of the [classname]#Item# interface are not -supported in the [classname]#RowItem# class: - - ----- -public boolean addItemProperty(Object id, Property property) -public boolean removeItemProperty(Object id) ----- - -[[sqlcontainer.nonimplemented.getitemids]] -== About the getItemIds() method - -To properly implement the Vaadin [classname]#Container# interface, a -[methodname]#getItemIds()# method has been implented in the -[classname]#SQLContainer#. By definition, this method returns a collection of -all the item IDs present in the container. What this means in the -[classname]#SQLContainer# case is that the container has to query the database -for the primary key columns of all the rows present in the connected database -table. - -It is obvious that this could potentially lead to fetching tens or even hundreds -of thousands of rows in an effort to satisfy the method caller. This will -effectively kill the lazy loading properties of [classname]#SQLContainer# and -therefore the following warning is expressed here: - - -[WARNING] -==== -It is highly recommended not to call the [methodname]#getitemIds()# method, -unless it is known that in the use case in question the item ID set will always -be of reasonable size. - -==== - - - - - - |