Module com.darkcollective.relix.lang.ast
Package com.darkcollective.relix.lang.ast

Record Class QueryStatement

java.lang.Object
java.lang.Record
com.darkcollective.relix.lang.ast.QueryStatement
Record Components:
target - the query target — a name reference or an inline expression
location - the source location of this statement; never null
All Implemented Interfaces:
Statement
public record QueryStatement(QueryTarget target, SourceLocation location) extends Record implements Statement
A query statement — produces output from a named symbol or an inline relational algebra expression.

Syntax forms: 

   query USCities;
   query { π name, country (Cities) };

Multiple query statements in a single script produce sequential outputs labelled by the target name (or a generated label for inline expressions).

  • Constructor Details

    • QueryStatement

      public QueryStatement(QueryTarget target, SourceLocation location)
      Creates an instance of a QueryStatement record class.
      Parameters:
      target - the value for the target record component
      location - the value for the location record component

    • QueryStatement

      public QueryStatement(QueryTarget target)
      Convenience constructor for tests; uses SourceLocation.UNKNOWN.

  • Method Details

    • toString

      public final String toString()
      Returns a string representation of this record class. The representation contains the name of the class, followed by the name and value of each of the record components.
      Specified by:
      toString in class Record
      Returns:
      a string representation of this object

    • hashCode

      public final int hashCode()
      Returns a hash code value for this object. The value is derived from the hash code of each of the record components.
      Specified by:
      hashCode in class Record
      Returns:
      a hash code value for this object

    • equals

      public final boolean equals(Object o)
      Indicates whether some other object is "equal to" this one. The objects are equal if the other object is of the same class and if all the record components are equal. All components in this record class are compared with Objects::equals(Object,Object).
      Specified by:
      equals in class Record
      Parameters:
      o - the object with which to compare
      Returns:
      true if this object is the same as the o argument; false otherwise.

    • target

      public QueryTarget target()
      Returns the value of the target record component.
      Returns:
      the value of the target record component

    • location

      public SourceLocation location()
      Returns the value of the location record component.
      Specified by:
      location in interface Statement
      Returns:
      the value of the location record component