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JEST defines URI syntax to access persistent resources over HTTP.

As an example, to find a persistent Person instance with primary key 1234 and receive the result in JSON format, an example URI would look like this (non functional URI):

The formal notation of a JEST URI is

  URI := http://{host}[:port]/{context}/{action}[/qualifier]* [?argument] [&argument]*

The URI syntax rules, in the light of the above example, are as follows:

  • protocol is always http

  • host ( and optional port number locates the JEST servlet

  • context (jest) identifies the context path of the JEST servlet. The context path is the servlet name as specified in the web deployment descriptor for JEST servlet

  • action (find) is the first segment of the servlet path. Allowed actions are find, query, domain, properties etc.

  • zero or more qualifier may constitute the servlet path. Each qualifier is separated by / character.

  • A qualifier must have a key and an optional value.
  • The qualifier key and value, if present, are separated by = sign.
  • A qualifier key is a valid Java identifier. The exact key is conditional on the action. For example, find action accepts format qualifier, query action accepts single, named, maxResult, firstResult, format as qualifiers. In the example above, format=json qualifies that the response of find action be formatted as JSON.
  • A qualifier may or may not have a value. For example, maxResult qualifier for query action must have an integer value while single qualifier does not.

  • zero or more argument may follow after the path by ? character.

  • each argument is separated by & character
  • An argument has an optional key and must have a value.
  • The argument key, if present, and value are separated by = sign.

  • some actions may enforce mandatory argument(s). For example, a find action must have type argument and at least one more argument for the primary key. A query action must have q argument etc.

List of supported actions, qualifiers and arguments

The following sections tabulates the currently supported actions and corresponding qualifiers and arguments. A bold font denotes qualifier or argument as mandatory.

Action: find

Returns the result of a find() operation.

qualifier-key qualifier-value Comment
format xml or json default is xml
plan name of one or more fetch plan(s). Each name separated by comma character.
e.g. find/plan=onlyBasicFields?type=Person&1234
where onlyBasicFields is name of a pre-defined Fetch Group
argument-key argument-value Comment
type entity name Fully-qualified Java class name or alias of the entity
primary key value can be used for simple identity without the id property name
e.g. /find?type=Person&1234
id property primary key value Used for compound primary keys
e.g. /find?type=Person&firstName=John&lastName=Doe

Action : query

Returns the result of a Query.getResultList() or Query.getSingleResult() operation.

qualifier-key qualifier-value Comment
format xml or json default is xml
plan name of one or more fetch plan(s). Each name separated by comma character.
single enforces single instance as query result
e.g. {{/query/single?q=select p from Person p where}}
named interprets the q argument value as a named query
e.g. /query/named?q=PersonByName&x=John
where PersonByName is named query with x its named parameter
argument-key argument-value Comment
q JPQL or Named Query e.g. /query/named?q=AllPerson
or {{/query?q=select p from Person p}}
e.g. {{/query?q=select p from Person p where p.firstName=:x&x=John}}
bind parameter parameter value the values are converted to match the target type
e.g. {{/query?q=select p from Person p where p.gender=:g&g=MALE}}

Action : domain

Returns the domain model in XML format.

Accepts no qualifier. Accepts no argument.

Action : properties

Returns the configuration properties in HTML format.

Accepts no qualifier. Accepts no argument.

Formal syntax:

URI := http://{host}[:port]/{context}/{action}[/qualifier]* [?argument][&argument]*

context         := JEST servlet context root
action          := find|query|domain|properties
qualifier       := qualifier-key[=qualifier-value]
argument        := [argument-key=] argument-value
qualifier-key   := any valid Java identifier 
qualifier-value := string
argument-key    := string 
argument-value  := string
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