| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package org.apache.pig.newplan.logical.expression; |
| |
| import java.util.List; |
| import org.apache.pig.data.DataType; |
| import org.apache.pig.impl.logicalLayer.FrontendException; |
| import org.apache.pig.newplan.Operator; |
| import org.apache.pig.newplan.OperatorPlan; |
| import org.apache.pig.newplan.PlanVisitor; |
| import org.apache.pig.newplan.logical.relational.LogicalSchema; |
| import org.apache.pig.newplan.logical.relational.LogicalSchema.LogicalFieldSchema; |
| import org.apache.pig.parser.SourceLocation; |
| |
| public class MapLookupExpression extends ColumnExpression { |
| |
| /** |
| * The key to lookup along with the type and schema corresponding to the |
| * type and schema of the value linked to the key |
| */ |
| private String mMapKey; |
| |
| public MapLookupExpression(OperatorPlan plan, String mapKey ) { |
| super("Map", plan); |
| mMapKey = mapKey; |
| plan.add(this); |
| } |
| /** |
| * @link org.apache.pig.newplan.Operator#accept(org.apache.pig.newplan.PlanVisitor) |
| */ |
| @Override |
| public void accept(PlanVisitor v) throws FrontendException { |
| if (!(v instanceof LogicalExpressionVisitor)) { |
| throw new FrontendException("Expected LogicalExpressionVisitor", 2222); |
| } |
| ((LogicalExpressionVisitor)v).visit(this); |
| } |
| |
| @Override |
| public boolean isEqual(Operator other) throws FrontendException { |
| if (other != null && other instanceof MapLookupExpression) { |
| MapLookupExpression po = (MapLookupExpression)other; |
| if ( po.mMapKey.compareTo(mMapKey) != 0) |
| return false; |
| else { |
| // check the nested map equality |
| if (plan.getSuccessors(this) != null) { |
| if (other.getPlan().getSuccessors(other) == null) |
| return false; |
| else { |
| return plan.getSuccessors(this).get(0).isEqual(other.getPlan().getSuccessors(other).get(0)); |
| } |
| } else if (other.getPlan().getSuccessors(other) != null) { |
| return false; |
| } else |
| return true; |
| } |
| } else { |
| return false; |
| } |
| } |
| |
| public LogicalExpression getMap() throws FrontendException { |
| List<Operator> preds = plan.getSuccessors(this); |
| if(preds == null) { |
| return null; |
| } |
| return (LogicalExpression)preds.get(0); |
| } |
| |
| public String getLookupKey() { |
| return mMapKey; |
| } |
| |
| public LogicalFieldSchema getFieldSchema() throws FrontendException { |
| if (fieldSchema!=null) |
| return fieldSchema; |
| LogicalExpression successor = (LogicalExpression)plan.getSuccessors(this).get(0); |
| LogicalFieldSchema predFS = successor.getFieldSchema(); |
| if (predFS!=null) { |
| if (predFS.type==DataType.MAP && predFS.schema!=null) { |
| fieldSchema = predFS.schema.getField(0); |
| return fieldSchema; |
| } |
| else { |
| fieldSchema = new LogicalSchema.LogicalFieldSchema(null, null, DataType.BYTEARRAY); |
| uidOnlyFieldSchema = fieldSchema.mergeUid(uidOnlyFieldSchema); |
| return fieldSchema; |
| } |
| } |
| return null; |
| } |
| |
| public String toString() { |
| StringBuilder msg = new StringBuilder(); |
| msg.append("(Name: " + name + " Type: "); |
| if (fieldSchema!=null) |
| msg.append(DataType.findTypeName(fieldSchema.type)); |
| else |
| msg.append("null"); |
| msg.append(" Uid: "); |
| if (fieldSchema!=null) |
| msg.append(fieldSchema.uid); |
| else |
| msg.append("null"); |
| msg.append(" Key: " + mMapKey); |
| msg.append(")"); |
| |
| return msg.toString(); |
| } |
| |
| @Override |
| public LogicalExpression deepCopy(LogicalExpressionPlan lgExpPlan) throws FrontendException { |
| LogicalExpression copy = null;; |
| copy = new MapLookupExpression( |
| lgExpPlan, |
| this.getLookupKey()); |
| |
| // Only one input is expected. |
| LogicalExpression input = (LogicalExpression) plan.getSuccessors( this ).get( 0 ); |
| LogicalExpression inputCopy = input.deepCopy( lgExpPlan ); |
| lgExpPlan.add( inputCopy ); |
| lgExpPlan.connect( copy, inputCopy ); |
| copy.setLocation( new SourceLocation( location ) ); |
| |
| return copy; |
| } |
| |
| } |