Package org.datanucleus.query.compiler

Package handling the compilation of queries.

See:
Description

Interface Summary

Parser

Interface for a parser of a query.

Class Summary

AbstractSymbolResolver	Base symbol resolver, to be extended for particular query languages.
JavaQueryCompiler	Typical implementation of a compiler for a java-based query language.
JDOQLCompiler	Implementation of a compiler for JDOQL (JSR0012, JSR0243).
JDOQLParser	Implementation of a parser for JDOQL query language.
JPQLCompiler	Implementation of a compiler for JPQL (JSR0220, JSR0317).
JPQLParser	Implementation of a parser for JPQL query language.
JPQLSymbolResolver	Symbol resolver for JPQL.
Lexer	Lexer for a Query.
QueryCompilation	Representation of the components of a compiled java "string-based" query.

Enum Summary

CompilationComponent

Enum defining the component of a query being compiled.

Package org.datanucleus.query.compiler Description

Package handling the compilation of queries. Provides compilation of "string-based" queries. Provides handling for different query languages such as JDOQL, JPQL and SQL(simplified). Compilation of a string-based query goes through two steps.

1. Parse of the string converting each component of the query into a Node tree
2. Compilation of the Node tree into an expression tree

From this tree the evaluation process can be configured to convert it into the native query language for the datastore; this part is handled within each datastore plugin. From this tree an in-memory evaluation can be performed. This is provided in the org.datanucleus.query.evaluator package and subpackage(s).