Package com.espertech.esper.common.client.soda

Class CountProjectionExpression

java.lang.Object
com.espertech.esper.common.client.soda.ExpressionBase
com.espertech.esper.common.client.soda.CountProjectionExpression
All Implemented Interfaces:
Expression, Serializable
public class CountProjectionExpression extends ExpressionBase
Count of the (distinct) values returned by an expression, equivalent to "count(distinct property)"
See Also:

  • Constructor Details

    • CountProjectionExpression

      public CountProjectionExpression()
      Ctor.

    • CountProjectionExpression

      public CountProjectionExpression(boolean isDistinct)
      Ctor - for use to create an expression tree, without inner expression
      Parameters:
      isDistinct - true if distinct

    • CountProjectionExpression

      public CountProjectionExpression(Expression expression, boolean isDistinct)
      Ctor - adds the expression to project.
      Parameters:
      expression - returning values to project
      isDistinct - true if distinct

  • Method Details

    • getPrecedence

      public ExpressionPrecedenceEnum getPrecedence()
      Description copied from interface: Expression
      Returns precedence.
      Returns:
      precedence

    • toPrecedenceFreeEPL

      public void toPrecedenceFreeEPL(StringWriter writer)
      Description copied from class: ExpressionBase
      Renders the expressions and all it's child expression, in full tree depth, as a string in language syntax.
      Specified by:
      toPrecedenceFreeEPL in class ExpressionBase
      Parameters:
      writer - is the output to use

    • isDistinct

      public boolean isDistinct()
      Returns true if the projection considers distinct values only.
      Returns:
      true if distinct

    • getDistinct

      public boolean getDistinct()
      Returns true if the projection considers distinct values only.
      Returns:
      true if distinct

    • setDistinct

      public void setDistinct(boolean distinct)
      Set the distinct flag indicating the projection considers distinct values only.
      Parameters:
      distinct - true for distinct, false for not distinct