How to use

create

method

in

org.apache.calcite.rex.RexProgram

@Override
public EnumerableRel implementEnumerable(List<EnumerableRel> inputs) {
  if (getInput() instanceof OLAPFilterRel) {
    // merge project & filter
    OLAPFilterRel filter = (OLAPFilterRel) getInput();
    RelNode inputOfFilter = inputs.get(0).getInput(0);
    RexProgram program = RexProgram.create(inputOfFilter.getRowType(), this.rewriteProjects,
        filter.getCondition(), this.rowType, getCluster().getRexBuilder());
    return new EnumerableCalc(getCluster(), getCluster().traitSetOf(EnumerableConvention.INSTANCE), //
        inputOfFilter, program);
  } else {
    // keep project for table scan
    EnumerableRel input = sole(inputs);
    RexProgram program = RexProgram.create(input.getRowType(), this.rewriteProjects, null, this.rowType,
        getCluster().getRexBuilder());
    return new EnumerableCalc(getCluster(), getCluster().traitSetOf(EnumerableConvention.INSTANCE), //
        input, program);
  }
}

/**
 * Creates a program which calculates projections and filters rows based
 * upon a condition. Does not attempt to eliminate common sub-expressions.
 *
 * @param projectExprs  Project expressions
 * @param conditionExpr Condition on which to filter rows, or null if rows
 *                      are not to be filtered
 * @param outputRowType Output row type
 * @param rexBuilder    Builder of rex expressions
 * @return A program
 */
public static RexProgram create(
  RelDataType inputRowType,
  List<? extends RexNode> projectExprs,
  RexNode conditionExpr,
  RelDataType outputRowType,
  RexBuilder rexBuilder) {
 return create(inputRowType, projectExprs, conditionExpr,
   outputRowType.getFieldNames(), rexBuilder);
}

/**
 * Creates a program which calculates projections and filters rows based
 * upon a condition. Does not attempt to eliminate common sub-expressions.
 *
 * @param projectExprs  Project expressions
 * @param conditionExpr Condition on which to filter rows, or null if rows
 *                      are not to be filtered
 * @param outputRowType Output row type
 * @param rexBuilder    Builder of rex expressions
 * @return A program
 */
public static RexProgram create(
  RelDataType inputRowType,
  List<? extends RexNode> projectExprs,
  RexNode conditionExpr,
  RelDataType outputRowType,
  RexBuilder rexBuilder) {
 return create(inputRowType, projectExprs, conditionExpr,
   outputRowType.getFieldNames(), rexBuilder);
}

 projects.add(rexBuilder.makeInputRef(enumerable, field));
RexProgram program = RexProgram.create(enumerable.getRowType(),
  projects, null, root.validatedRowType, rexBuilder);
enumerable = EnumerableCalc.create(enumerable, program);

 projects.add(rexBuilder.makeInputRef(enumerable, field));
RexProgram program = RexProgram.create(enumerable.getRowType(),
  projects, null, root.validatedRowType, rexBuilder);
enumerable = EnumerableCalc.create(enumerable, program);

 projects.add(rexBuilder.makeInputRef(enumerable, field));
RexProgram program = RexProgram.create(enumerable.getRowType(),
  projects, null, root.validatedRowType, rexBuilder);
enumerable = EnumerableCalc.create(enumerable, program);

 public void onMatch(RelOptRuleCall call) {
  final EnumerableProject project = call.rel(0);
  final RelNode input = project.getInput();
  final RexProgram program =
    RexProgram.create(input.getRowType(),
      project.getProjects(),
      null,
      project.getRowType(),
      project.getCluster().getRexBuilder());
  final EnumerableCalc calc = EnumerableCalc.create(input, program);
  call.transformTo(calc);
 }
}

 public void onMatch(RelOptRuleCall call) {
  final EnumerableProject project = call.rel(0);
  final RelNode input = project.getInput();
  final RexProgram program =
    RexProgram.create(input.getRowType(),
      project.getProjects(),
      null,
      project.getRowType(),
      project.getCluster().getRexBuilder());
  final EnumerableCalc calc = EnumerableCalc.create(input, program);
  call.transformTo(calc);
 }
}

 public void onMatch(RelOptRuleCall call) {
  final LogicalProject project = call.rel(0);
  final RelNode input = project.getInput();
  final RexProgram program =
    RexProgram.create(
      input.getRowType(),
      project.getProjects(),
      null,
      project.getRowType(),
      project.getCluster().getRexBuilder());
  final LogicalCalc calc = LogicalCalc.create(input, program);
  call.transformTo(calc);
 }
}

 public void onMatch(RelOptRuleCall call) {
  final LogicalProject project = call.rel(0);
  final RelNode input = project.getInput();
  final RexProgram program =
    RexProgram.create(
      input.getRowType(),
      project.getProjects(),
      null,
      project.getRowType(),
      project.getCluster().getRexBuilder());
  final LogicalCalc calc = LogicalCalc.create(input, program);
  call.transformTo(calc);
 }
}

@Override
public EnumerableRel implementEnumerable(List<EnumerableRel> inputs) {
  if (getInput() instanceof OLAPFilterRel) {
    // merge project & filter
    OLAPFilterRel filter = (OLAPFilterRel) getInput();
    RelNode inputOfFilter = inputs.get(0).getInput(0);
    RexProgram program = RexProgram.create(inputOfFilter.getRowType(), this.rewriteProjects,
        filter.getCondition(), this.rowType, getCluster().getRexBuilder());
    return new EnumerableCalc(getCluster(), getCluster().traitSetOf(EnumerableConvention.INSTANCE), //
        inputOfFilter, program);
  } else {
    // keep project for table scan
    EnumerableRel input = sole(inputs);
    RexProgram program = RexProgram.create(input.getRowType(), this.rewriteProjects, null, this.rowType,
        getCluster().getRexBuilder());
    return new EnumerableCalc(getCluster(), getCluster().traitSetOf(EnumerableConvention.INSTANCE), //
        input, program);
  }
}

final RelNode input = project.getInput();
final RexProgram program =
  RexProgram.create(
    input.getRowType(),
    project.getProjects(),

final RelNode input = project.getInput();
final RexProgram program =
  RexProgram.create(
    input.getRowType(),
    project.getProjects(),

RexProgram.create(
  joinChildrenRowType,
  Pair.left(projects),

RexProgram.create(
  joinChildrenRowType,
  Pair.left(projects),

RexProgram.create(
  calc.getRowType(),
  project.getProjects(),

RexProgram.create(
  calc.getRowType(),
  project.getProjects(),