Examples with SelectedPositions io.prestosql.operator.project.SelectedPositions used on opensource projects

Example 1 with SelectedPositions

use of io.prestosql.operator.project.SelectedPositions in project hetu-core by openlookeng.

the class PageFunctionCompiler method generatePageFilterMethod.

private static MethodDefinition generatePageFilterMethod(ClassDefinition classDefinition, FieldDefinition selectedPositionsField) {
    Parameter session = arg("session", ConnectorSession.class);
    Parameter page = arg("page", Page.class);
    MethodDefinition method = classDefinition.declareMethod(a(PUBLIC), "filter", type(SelectedPositions.class), ImmutableList.<Parameter>builder().add(session).add(page).build());
    Scope scope = method.getScope();
    Variable thisVariable = method.getThis();
    BytecodeBlock body = method.getBody();
    Variable positionCount = scope.declareVariable("positionCount", body, page.invoke("getPositionCount", int.class));
    body.append(new IfStatement("grow selectedPositions if necessary").condition(lessThan(thisVariable.getField(selectedPositionsField).length(), positionCount)).ifTrue(thisVariable.setField(selectedPositionsField, newArray(type(boolean[].class), positionCount))));
    Variable selectedPositions = scope.declareVariable("selectedPositions", body, thisVariable.getField(selectedPositionsField));
    Variable position = scope.declareVariable(int.class, "position");
    body.append(new ForLoop().initialize(position.set(constantInt(0))).condition(lessThan(position, positionCount)).update(position.increment()).body(selectedPositions.setElement(position, thisVariable.invoke("filter", boolean.class, session, page, position))));
    body.append(invokeStatic(PageFilter.class, "positionsArrayToSelectedPositions", SelectedPositions.class, selectedPositions, positionCount).ret());
    return method;
}