THIS IS A TEST INSTANCE. ALL YOUR CHANGES WILL BE LOST!!!!
JEST is a REST style access to any OpenJPA runtime.
REST (Representational State Transfer) is a foundational concept in the architecture for World Wide Web. JEST promotes REST style interaction between a client and an application based on OpenJPA. A JEST-enabled OpenJPA runtime embeds a specialized HTTP server such that a JEST can be deployed in as a servlet for a web application using OpenJPA as a persistence provider. A client (neither necessarily in Java nor having any definition of the persistent server objects) can send HTTP requests and receive persistent data as response in JSON, XML or other string based format.
Effectively there are three aspects to JEST
JEST is described under the following sections
- URI Syntax Protocol of client-server communication
- Representation of persistent state
- Transaction semantics
Protocol
The communication protocol for JEST is HTTP. The client sends request in standard HTTP URI (Uniform Resource Identifier) e.g. http://www.jpa.com:6789/find?Person&John to a JEST-enabled OpenJPA application to find a Person with primary key 'John'. The server will send a HTTP response back to the client. The content of the HTTP response can be formatted as XML or as JSON. The URI syntax governs the server response. Before describing the syntax in detail, here are few typical example URI and their associated effect on the server.
| Server Function | JEST URI |
|---|---|---|
01 | Get name of the persistent unit | http://www.jpa.com:6789/ |
02 | List simple name of the domain classes | http://www.jpa.com:6789/domain |
03 | List the key-value properties of the persistent unit | http://www.jpa.com:6789/properties |
04 | Find an instance by key | http://www.jpa.com:6789/find?Person&123456789 |
05 | Find an instance by key | http://www.jpa.com:6789/find?Person&ssn=123456789&name=John |
06 | Get the result of the query with no parameter | http://www.jpa.com:6789/query?select p from Person p |
07 | Get the result of the query with single parameter | http://www.jpa.com:6789/query?select p from Person p where p.name=:name&name=John |
08.1 | Get the result of the query with multiple parameters | http://www.jpa.com:6789/query?select p from Person p where p.name=:name and age > :age&name=John&age=20 |
08.2 |
| http://www.jpa.com:6789/query?select p from Person p where p.first=:first and p.last=:last&first=John&last=Doe |
09 | Get the single result of the query | http://www.jpa.com:6789/query/single?select p from Person p where p.name=:name&name=John |
10 | Get the result of the named query | http://www.jpa.com:6789/query/named?QueryPersonByName&name=John |
11.1 | Get the single result of the named query | http://www.jpa.com:6789/query/single/named?QueryPersonByName&name=John |
11.2 | or | http://www.jpa.com:6789/query/named/single?QueryPersonByName&name=John |
12 | Get first 20 rows of query using a fetch plan | http://www.jpa.com:6789/query/fecthplan=myPlan/ignoreCache/maxResult=20?select p from Person p |
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| title | URI syntax for JEST |
|---|
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