DataNucleus AccessPlatform is a standards-compliant Java persistence product. It is fully compliant with the JDO1, JDO2, JDO2.1, JDO2.2, JDO3, JPA1, JPA2 and JPA2.1 Java standards, and provides a REST API. It complies with the OGC Simple Feature Spec for persistence of geospatial Java types. It allows access to all popular RDBMS available today, together with the MongoDB, LDAP, NeoDatis, JSON, Excel/ODF spreadsheets, XML, BigTable, HBase, and Neo4j databases.
Spinneret is a structured storage engine that can be thought of as an extended tuple storage system. It takes the best aspects of relational, object, and hierarchical databases and throws away the dead weight associated with those technologies. The benefit of Spinneret is that its data model is incredibly flexible, allowing it to expose its underlying data in any number of ways. It operates similar to an object database, but without hard ties to an originating language, and can also behave like a relational database without the burden of complex joins.
Morph is a Java framework that eases the internal interoperability of an application. As information flows through an application, it undergoes multiple transformations. Morph provides a standard way to implement these transformations. In addition to providing a framework for performing transformations, Morph provides implementations of many common transformations. It has been built from the ground up for flexibility and extensibility, and it integrates seamlessly with dependency injection frameworks such as Spring, PicoContainer, and Hivemind.
Ammentos is a lightweight persistence framework for JDK 5. It does not require any installation nor configuration; just put a jar file into your classpath and start writing code. It is designed so that your persistence code will be dramatically short and so that you won't have to spend a lot of time to learn how to use it. It is about 72Kb large and it does not require any external library except for your database JDBC driver. You can use it in desktop applications or in server-based environments.
OrientDB is a NoSQL DBMS which can store 150,000 documents per second on common hardware. Even with a document-based database, the relationships are managed as in graph databases, with direct connections among records. You can traverse entire or parts of trees and graphs of records in a few milliseconds. It supports schema-less, schema-full, and schema-mixed modes, has a strong security profiling system based on users and roles, and supports SQL between the query languages. Thanks to the SQL layer, it's straightforward to use for people skilled in the relational world.
With MetaModel, you use a type-safe SQL-like API for querying any datastore. It is a data access framework providing a common interface for exploration and querying of different types of datastores. It isn't a data mapping framework. Instead, it emphasizes abstraction of metadata and the ability to add data sources at runtime, making MetaModel great for generic data processing applications, but less so for applications modeled around a particular domain.
Hades is a high availability (HA) data source. This HA data source contains two other data sources: the main one and the failover one. The HA data source exposes one of them at a time and can automatically switch between them when certain conditions are met. These conditions are highly configurable. By default, when the main data source is overloaded, the failover data source is used. The load of a data base is determined on the basis of the average execution time of some configurable SQL statement that is examined periodically. The HA data source exposes through JMX its state and also operations for manual switching between the two contained data sources in case automatic switching must be suppressed for some reason.
Ujorm is an easy-to-use ORM framework based on key-value objects. The framework was designed for rapid Java development with great performance and a small footprint. The key features are type safe queries, relation mapping by Java code, no entity states, and a memory overloading protection cache.
Redland is a set of C libraries providing a high-level API for the Resource Description Framework (RDF), allowing it to be stored, parsed, serialized, queried, and manipulated. It has an object-based, modular design and comes with detailed reference documentation and examples. Redland supports all RDF vocabularies such as FOAF, RSS 1.0, Dublin Core, DOAP, and OWL, the query languages SPARQL and RDQL, and all RDF syntaxes including Turtle, RDF/XML, RDF/JSON, RSS, Atom, RDFa, and GRDDL.