| package edu.uci.ics.asterix.om.typecomputer.impl; |
| |
| |
| import edu.uci.ics.asterix.om.typecomputer.base.IResultTypeComputer; |
| import edu.uci.ics.asterix.om.types.ATypeTag; |
| import edu.uci.ics.asterix.om.types.AUnionType; |
| import edu.uci.ics.asterix.om.types.AbstractCollectionType; |
| import edu.uci.ics.asterix.om.types.IAType; |
| import edu.uci.ics.asterix.om.types.TypeHelper; |
| import edu.uci.ics.hyracks.algebricks.common.exceptions.AlgebricksException; |
| import edu.uci.ics.hyracks.algebricks.core.algebra.base.ILogicalExpression; |
| import edu.uci.ics.hyracks.algebricks.core.algebra.expressions.AbstractFunctionCallExpression; |
| import edu.uci.ics.hyracks.algebricks.core.algebra.expressions.IVariableTypeEnvironment; |
| import edu.uci.ics.hyracks.algebricks.core.algebra.metadata.IMetadataProvider; |
| |
| public class ScalarVersionOfAggregateResultType implements IResultTypeComputer { |
| |
| public static final ScalarVersionOfAggregateResultType INSTANCE = new ScalarVersionOfAggregateResultType(); |
| |
| private ScalarVersionOfAggregateResultType() { |
| } |
| |
| @Override |
| public IAType computeType(ILogicalExpression expression, IVariableTypeEnvironment env, |
| IMetadataProvider<?, ?> metadataProvider) throws AlgebricksException { |
| AbstractFunctionCallExpression fce = (AbstractFunctionCallExpression) expression; |
| ILogicalExpression arg1 = fce.getArguments().get(0).getValue(); |
| IAType t1 = (IAType) env.getType(arg1); |
| IAType nonOpt = TypeHelper.getNonOptionalType(t1); |
| ATypeTag tag1 = nonOpt.getTypeTag(); |
| if (tag1 != ATypeTag.ORDEREDLIST && tag1 != ATypeTag.UNORDEREDLIST) { |
| throw new AlgebricksException("Type of argument in " + expression |
| + " should be a collection type instead of " + t1); |
| } |
| AbstractCollectionType act = (AbstractCollectionType) nonOpt; |
| IAType t = act.getItemType(); |
| if (TypeHelper.canBeNull(t)) { |
| return t; |
| } else { |
| return AUnionType.createNullableType(t); |
| } |
| } |
| |
| } |