trunk/chemistry-opencmis-samples/chemistry-opencmis-queryparser/readme.txt - chemistry-opencmis - Git at Google

 Readme.txt chemistry-opencmis-queryparser-example
 =================================================

 This project is an example how to build a query parser using the OpenCMIS query framework.

 The example is standalone program that makes use of the AntLR based query parser. It
 parses a CMIS query string and creates after traversing the syntax tree a new statement in
 CMIS query language. While this sounds pretty useless this sample still has value:
  - it is not dependent on any query language of a backend (like a database) or a
    specific database scheme.
  - it can be easily adapted to generate output in different format (SQL, XML, JSON)
  - it separates classes that can be reused from those that are specific to the output
    language
  - it provides unit tests that can be adapted to other target languages.

 The sample provides code for the full cycle to parse and process a query. The entry point
 is a static main() method so that it runs standalone without any server. Usually this code
 will be called from the CMIS Discovery service in a real CMIS server.

 The code consists of the following classes:

 ExampleQueryProcessor.java:
 This is the main class. It takes a query and parses it. It traverses the generated tree
 and finally builds the output.

 ExampleQueryWalker.java:
 A walker that traverses the syntax tree and generates the CMISQL output. For each node in
 the tree callback functions are provided processing a specific token.

 ExampleTypeManager.java:
 An OpenCMIS parser processes the query and does certain checks for validity. To do this
 it needs information about the available types and properties in the backend. This
 information is provided by the interface TypeManager. This class implements a minimal
 type system to get a running sample. It has only one type implemented: cmis:document
 (note that this is not allowed for a real server according to the CMIS spec).

 ExtendedAbstractPredicateWalker.java
 This class extends the predefined walker from the server support package. It provides
 more fine grained control and more hooks to plugin while traversing the tree. This part
 is independent of the generated output and therefore separated in its own class. It may
 be reused for other projects.

 ExampleQueryProcessorTest.java
 A Junit test that feeds the parser with CMISQL queries and compares the generated output
 against an expected result. While the tests are specific to the output language the basic
 principles and design of the unit test can be done in the same way for other parsers.
	Readme.txt chemistry-opencmis-queryparser-example
	=================================================

	This project is an example how to build a query parser using the OpenCMIS query framework.

	The example is standalone program that makes use of the AntLR based query parser. It
	parses a CMIS query string and creates after traversing the syntax tree a new statement in
	CMIS query language. While this sounds pretty useless this sample still has value:
	- it is not dependent on any query language of a backend (like a database) or a
	specific database scheme.
	- it can be easily adapted to generate output in different format (SQL, XML, JSON)
	- it separates classes that can be reused from those that are specific to the output
	language
	- it provides unit tests that can be adapted to other target languages.

	The sample provides code for the full cycle to parse and process a query. The entry point
	is a static main() method so that it runs standalone without any server. Usually this code
	will be called from the CMIS Discovery service in a real CMIS server.

	The code consists of the following classes:

	ExampleQueryProcessor.java:
	This is the main class. It takes a query and parses it. It traverses the generated tree
	and finally builds the output.

	ExampleQueryWalker.java:
	A walker that traverses the syntax tree and generates the CMISQL output. For each node in
	the tree callback functions are provided processing a specific token.

	ExampleTypeManager.java:
	An OpenCMIS parser processes the query and does certain checks for validity. To do this
	it needs information about the available types and properties in the backend. This
	information is provided by the interface TypeManager. This class implements a minimal
	type system to get a running sample. It has only one type implemented: cmis:document
	(note that this is not allowed for a real server according to the CMIS spec).

	ExtendedAbstractPredicateWalker.java
	This class extends the predefined walker from the server support package. It provides
	more fine grained control and more hooks to plugin while traversing the tree. This part
	is independent of the generated output and therefore separated in its own class. It may
	be reused for other projects.

	ExampleQueryProcessorTest.java
	A Junit test that feeds the parser with CMISQL queries and compares the generated output
	against an expected result. While the tests are specific to the output language the basic
	principles and design of the unit test can be done in the same way for other parsers.