Package org.datanucleus.store.query.compiler

Class JavaQueryCompiler

  • All Implemented Interfaces:
    SymbolResolver
    Direct Known Subclasses:
    JDOQLCompiler, JPQLCompiler
    public abstract class JavaQueryCompiler
extends java.lang.Object
implements SymbolResolver
    Typical implementation of a compiler for a java-based query language. The constructor takes in the components of the query, and the method compile() compiles it returning the compiled query, for use elsewhere.

    Each "Expression" is effectively a tree of Expressions. You can navigate through each expression based on their type. For example, a DyadicExpression has a "left" and "right" and an operator between them. The left could also be a DyadicExpression, so you would navigate to its left/right components etc etc.

    • Field Detail

      • JOIN_INNER_FETCH

        public static final java.lang.String JOIN_INNER_FETCH
        See Also:
        Constant Field Values

      • JOIN_OUTER_FETCH

        public static final java.lang.String JOIN_OUTER_FETCH
        See Also:
        Constant Field Values

      • JOIN_OUTER_RIGHT

        public static final java.lang.String JOIN_OUTER_RIGHT
        See Also:
        Constant Field Values

      • JOIN_OUTER_FETCH_RIGHT

        public static final java.lang.String JOIN_OUTER_FETCH_RIGHT
        See Also:
        Constant Field Values

      • parameterSubtitutionMap

        protected java.util.Map<java.lang.Object,​java.lang.String> parameterSubtitutionMap

      • parameterSubstitutionNumber

        protected int parameterSubstitutionNumber

      • caseSensitiveAliases

        protected boolean caseSensitiveAliases

      • candidateClass

        protected java.lang.Class candidateClass
        Primary candidate class (if defined).

      • candidateAlias

        protected java.lang.String candidateAlias
        Alias for the primary candidate. Default to "this" (JDOQL) but can be set.

      • candidateAliasOrig

        protected java.lang.String candidateAliasOrig
        Default candidate alias in use (only set when in a subquery and the same as the outer query).

      • from

        protected java.lang.String from

      • candidates

        protected java.util.Collection candidates

      • update

        protected java.lang.String update

      • filter

        protected java.lang.String filter

      • ordering

        protected java.lang.String ordering

      • parameters

        protected java.lang.String parameters

      • variables

        protected java.lang.String variables

      • grouping

        protected java.lang.String grouping

      • having

        protected java.lang.String having

      • result

        protected java.lang.String result

      • imports

        protected Imports imports

      • symtbl

        protected SymbolTable symtbl
        Compiled Symbol Table.

      • parser

        protected Parser parser
        Parser specific to the type of query being compiled.

      • options

        protected java.util.Map<java.lang.String,​java.lang.Object> options

    • Constructor Detail

      • JavaQueryCompiler

        public JavaQueryCompiler​(PersistenceNucleusContext nucCtx,
                         ClassLoaderResolver clr,
                         java.lang.String from,
                         java.lang.Class candidateClass,
                         java.util.Collection candidates,
                         java.lang.String filter,
                         Imports imports,
                         java.lang.String ordering,
                         java.lang.String result,
                         java.lang.String grouping,
                         java.lang.String having,
                         java.lang.String params,
                         java.lang.String variables,
                         java.lang.String update)

    • Method Detail

      • getLanguage

        public abstract java.lang.String getLanguage()
        Accessor for the query language name.
        Returns:
        Name of the query language.

      • setOption

        public void setOption​(java.lang.String name,
                      java.lang.Object value)

      • setLinkToParentQuery

        public void setLinkToParentQuery​(JavaQueryCompiler parentCompiler,
                                 java.util.Map<java.lang.Object,​java.lang.String> paramSubstitutionMap)
        Method to set the linkage to the parent query.
        Parameters:
        parentCompiler - Compiler for the parent query
        paramSubstitutionMap - Map of parameters in this subquery and what they are in the parent query.

      • compile

        public abstract QueryCompilation compile​(java.util.Map parameters,
                                         java.util.Map<java.lang.String,​java.lang.Object> subqueryMap)
        Method to compile the query.
        Parameters:
        parameters - The parameter values keyed by name.
        subqueryMap - Map of subqueries keyed by the subquery name
        Returns:
        The query compilation

      • compileCandidatesParametersVariables

        public void compileCandidatesParametersVariables​(java.util.Map parameters)
        Compile the candidates, variables and parameters.
        Parameters:
        parameters - Map of parameter values keyed by their name

      • compileFrom

        protected Expression[] compileFrom()
        Method to compile the "from" clause (if present for the query language).
        Returns:
        The compiled from expression(s)

      • getClassForSubqueryClassExpression

        private java.lang.Class getClassForSubqueryClassExpression​(java.lang.String classExpr)
        Convenience method to find the class that a subquery class expression refers to. Allows for reference to the parent query candidate class, or to a class name.
        Parameters:
        classExpr - The class expression
        Returns:
        The class that it refers to

      • compileCandidates

        private void compileCandidates()

      • compileUpdate

        public Expression[] compileUpdate()

      • compileFilter

        public Expression compileFilter()
        Compile the filter and return the compiled expression.
        Returns:
        The compiled expression

      • swapCandidateAliasNodeName

        protected void swapCandidateAliasNodeName​(Node node)
        Convenience method that takes the input node and if it is set to the original candidate alias then swaps the value to the candidate alias. This is for the situation where we have a subquery which had no alias defined so defaults to "this" (the same as the outer query), so we change the subquery alias from "this" to "sub_this".
        Parameters:
        node - The node to process

      • swapSubqueryParameters

        protected Node swapSubqueryParameters​(Node node)
        Convenience method that takes the input node if it is a parameter node and swaps the node
        Parameters:
        node - The node to process
        Returns:
        The Node with the swap

      • compileResult

        public Expression[] compileResult()

      • compileGrouping

        public Expression[] compileGrouping()

      • compileHaving

        public Expression compileHaving()

      • compileVariables

        private void compileVariables()

      • compileParameters

        private void compileParameters()

      • compileOrdering

        public Expression[] compileOrdering()

      • getPrimaryClass

        public java.lang.Class getPrimaryClass()
        Description copied from interface: SymbolResolver
        Accessor for the candidate class of the query.
        Specified by:
        getPrimaryClass in interface SymbolResolver
        Returns:
        The candidate class

      • resolveClass

        public java.lang.Class resolveClass​(java.lang.String className)
        Method to perform a lookup of the class name from the input name. Makes use of the query "imports" and the lookup to "entity name".
        Specified by:
        resolveClass in interface SymbolResolver
        Parameters:
        className - Name of the class
        Returns:
        The class corresponding to this name
        Throws:
        ClassNotResolvedException - thrown if not resolvable using imports or entity name

      • getType

        public java.lang.Class getType​(java.util.List<java.lang.String> tuples)
        Specified by:
        getType in interface SymbolResolver

      • getType

        java.lang.Class getType​(java.lang.Class cls,
                        java.lang.String fieldName,
                        boolean lastEntry)

      • isKeyword

        protected abstract boolean isKeyword​(java.lang.String name)
        Method to return if the supplied name is a keyword. Keywords can only appear at particular places in a query so we need to detect for valid queries.
        Parameters:
        name - The name
        Returns:
        Whether it is a keyword