Lazy Query Container addon provides container with support for normal reads and lazy loading reads from sources like WebService client, JDBC connection, JPA context, NoSQL database or Java services.
Lazy Query Container (LQC) is a Vaadin framework addon which provides lazy loading container for Vaadin tables. LQC includes non lazy container versions as well which use same query implementations as lazy containers.
See Ilves Framework for practical LQC implementation examples. The link can be found in the link list on the right. Use key word LazyQueryContainer in the search box to find the right classes.
All containers support buffered reads and writes of items. Data reads and writes are delegated through Query interface to an application specific business delegate.
The QueryFactory and Query interface implementations are designed to be application specific and should invoke a data source like WebService client, JDBC connection, JPA context or Java service class to read and write data items. The data source has to support querying data in batches.
Lazy Query Container supports the following features: non lazy loading, lazy loading, caching, sorting, filtering, statistics, item property as ID, item index as ID and adding & removing properties (columns). Lazy Query Container also supports adding items, modifying items and removing items. The changes are buffered and can be either commited or discarded. Row status icons and status column generator are also included to allow for visualization of row states. See the demo for hands on experience on the features.
- QueryContainer and LazyQueryContainer for custom data sources.
- EntityContainer and LazyEntityContainer for JPA. ** Vaadin Container Filters are mapped to JPA 2.0 Criteria API queries. ** Both container and application managed transactions are supported. ** Both attached and detached entities are supported. ** Nested properties are fully supported.
Other utility classes (see Wiki page for examples):
- CompositeItem for combining beans and dynamic properties.
- BeanQueryFactory for queries loading JavaBeans. ** Nested properties are fully supported.