Package com.espertech.esper.common.client.hook.aggfunc

Class AggregationFunctionValidationContext

java.lang.Object
com.espertech.esper.common.client.hook.aggfunc.AggregationFunctionValidationContext
public class AggregationFunctionValidationContext extends Object
Context for use with plug-in custom aggregation functions that implement AggregationFunctionForge.

This context object provides access to the parameter expressions themselves as well as information compiled from the parameter expressions for your convenience.

  • Constructor Summary

    Constructors
    Constructor
    Description
    AggregationFunctionValidationContext(EPType[] parameterTypes, boolean[] constantValue, Object[] constantValues, boolean distinct, boolean windowed, com.espertech.esper.common.internal.epl.expression.core.ExprNode[] expressions, LinkedHashMap<String,List<com.espertech.esper.common.internal.epl.expression.core.ExprNode>> namedParameters)
    Ctor.

  • Method Summary

    Modifier and Type
    Method
    Description
    Object[]
    getConstantValues()
    If a parameter expression returns a constant value, the value of the constant it returns is provided in this array.
    com.espertech.esper.common.internal.epl.expression.core.ExprNode[]
    getExpressions()
    Returns the parameter expressions themselves for interrogation.
    boolean[]
    getIsConstantValue()
    A boolean indicator for each parameter expression that is true if the expression returns a constant result or false if the expression result is not a constant value.
    LinkedHashMap<String,List<com.espertech.esper.common.internal.epl.expression.core.ExprNode>>
    getNamedParameters()
    Returns any named parameters or null if there are no named parameters
    EPType[]
    getParameterTypes()
    The return type of each parameter expression.
    boolean
    isDistinct()
    Returns true to indicate that the 'distinct' keyword was specified for this aggregation function.
    boolean
    isWindowed()
    Returns true to indicate that all parameter expressions return event properties that originate from a stream that provides a remove stream.

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  • Constructor Details

    • AggregationFunctionValidationContext

      public AggregationFunctionValidationContext(EPType[] parameterTypes, boolean[] constantValue, Object[] constantValues, boolean distinct, boolean windowed, com.espertech.esper.common.internal.epl.expression.core.ExprNode[] expressions, LinkedHashMap<String,List<com.espertech.esper.common.internal.epl.expression.core.ExprNode>> namedParameters)
      Ctor.
      Parameters:
      parameterTypes - the type of each parameter expression.
      constantValue - for each parameter expression an indicator whether the expression returns a constant result
      constantValues - for each parameter expression that returns a constant result this array contains the constant value
      distinct - true if 'distinct' keyword was provided
      windowed - true if all event properties references by parameter expressions are from streams that have data windows declared onto the stream or are from named windows
      expressions - the parameter expressions themselves (positional parameters only)
      namedParameters - provided when there are named parameters, such as the "filter:expression" parameter

  • Method Details

    • getParameterTypes

      public EPType[] getParameterTypes()
      The return type of each parameter expression.

      This information can also be obtained by calling getType on each parameter expression.

      Returns:
      array providing result type of each parameter expression

    • getIsConstantValue

      public boolean[] getIsConstantValue()
      A boolean indicator for each parameter expression that is true if the expression returns a constant result or false if the expression result is not a constant value.

      This information can also be obtained by calling isConstantResult on each parameter expression.

      Returns:
      array providing an indicator per parameter expression that the result is a constant value

    • getConstantValues

      public Object[] getConstantValues()
      If a parameter expression returns a constant value, the value of the constant it returns is provided in this array.

      This information can also be obtained by calling evaluate on each parameter expression providing a constant value.

      Returns:
      array providing the constant return value per parameter expression that has constant result value, or null if a parameter expression is deemded to not provide a constant result value

    • isDistinct

      public boolean isDistinct()
      Returns true to indicate that the 'distinct' keyword was specified for this aggregation function.
      Returns:
      distinct value indicator

    • isWindowed

      public boolean isWindowed()
      Returns true to indicate that all parameter expressions return event properties that originate from a stream that provides a remove stream.
      Returns:
      windowed indicator

    • getExpressions

      public com.espertech.esper.common.internal.epl.expression.core.ExprNode[] getExpressions()
      Returns the parameter expressions themselves for interrogation.
      Returns:
      parameter expressions

    • getNamedParameters

      public LinkedHashMap<String,List<com.espertech.esper.common.internal.epl.expression.core.ExprNode>> getNamedParameters()
      Returns any named parameters or null if there are no named parameters
      Returns:
      named parameters