com.gemstone.gemfire.cache.query
Interface Query

public interface Query

Interface for query objects. Supports execution of queries with optional parameters.

Since:

4.0

Method Summary

void	compile() Compiles this Query to achieve higher performance execution.
Object	execute() Execute this query and returns an object that represent its result.
Object	execute(Object[] params) Executes this query with the given parameters and returns an object that represent its result.
String	getQueryString() Return the original query string that was specified in the constructor.
QueryStatistics	getStatistics() Get statistics information for this query.
boolean	isCompiled() Return whether this query has been compiled into VM bytecodes.

Method Detail

getQueryString

String getQueryString()

Return the original query string that was specified in the constructor.

Returns:

the original query string

execute

Object execute()
               throws FunctionDomainException,
                      TypeMismatchException,
                      NameResolutionException,
                      QueryInvocationTargetException

Execute this query and returns an object that represent its result. If the query resolves to a primitive type, an instance of the corresponding wrapper type (Integer, etc.) is returned. If the query resolves to more than one object, a SelectResults is returned.

Returns:

The object that represents the result of the query. Note that if a query is just a select statement then it will return a result that is an instance of SelectResults. However, since a query is not necessarily just a select statement, the return type of this method is Object. For example, the query (select distinct * from /rgn).size returns an instance of java.lang.Integer.

Throws:

FunctionDomainException - A function was applied to a parameter that is improper for that function. For example, the ELEMENT function was applied to a collection of more than one element

TypeMismatchException - If a bound parameter is not of the expected type.

NameResolutionException - If a name in the query cannot be resolved.

IllegalArgumentException - The number of bound parameters does not match the number of placeholders

IllegalStateException - If the query is not permitted on this type of region

QueryInvocationTargetException

execute

Object execute(Object[] params)
               throws FunctionDomainException,
                      TypeMismatchException,
                      NameResolutionException,
                      QueryInvocationTargetException

Executes this query with the given parameters and returns an object that represent its result. If the query resolves to a primitive type, an instance of the corresponding wrapper type (Integer, etc.) is returned. If the query resolves to more than one object, a SelectResults is returned.

Parameters:

params - Values that are bound to parameters (such as $1) in this query.

Returns:

The object that represents the result of the query. Note that if a query is just a select statement then it will return a result that is an instance of SelectResults. However, since a query is not necessarily just a select statement, the return type of this method is Object. For example, the query (select distinct * from /rgn).size returns an instance of java.lang.Integer.

Throws:

FunctionDomainException - A function was applied to a parameter that is improper for that function. For example, the ELEMENT function was applied to a collection of more than one element

TypeMismatchException - If a bound parameter is not of the expected type.

NameResolutionException - If a name in the query cannot be resolved.

IllegalArgumentException - The number of bound parameters does not match the number of placeholders

IllegalStateException - If the query is not permitted on this type of region

QueryInvocationTargetException

compile

void compile()
             throws TypeMismatchException,
                    NameResolutionException

Compiles this Query to achieve higher performance execution.

Throws:

TypeMismatchException - If the compile-time type of a name, parameter, or expression is not the expected type

QueryInvalidException - The syntax of the query string is not correct

NameResolutionException

isCompiled

boolean isCompiled()

Return whether this query has been compiled into VM bytecodes.

Returns:

true if this query has been compiled into bytecodes

getStatistics

QueryStatistics getStatistics()

Get statistics information for this query.