/*
* 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 org.apache.pig.FuncSpec;
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.parser.SourceLocation;
public class CastExpression extends UnaryExpression {
private FuncSpec castFunc;
private LogicalSchema.LogicalFieldSchema castSchema;
public CastExpression(OperatorPlan plan, LogicalExpression exp, LogicalSchema.LogicalFieldSchema fs) {
super("Cast", plan, exp);
castSchema = fs.deepCopy();
castSchema.resetUid();
}
@Override
public void accept(PlanVisitor v) throws FrontendException {
if (!(v instanceof LogicalExpressionVisitor)) {
throw new FrontendException("Expected LogicalExpressionVisitor", 2222);
}
((LogicalExpressionVisitor)v).visit(this);
}
/**
* Set the <code>FuncSpec</code> that performs the casting functionality
* @param spec the <code>FuncSpec</code> that does the casting
*/
public void setFuncSpec(FuncSpec spec) {
castFunc = spec;
}
/**
* Get the <code>FuncSpec</code> that performs the casting functionality
* @return the <code>FuncSpec</code> that does the casting
*/
public FuncSpec getFuncSpec() {
return castFunc;
}
@Override
public boolean isEqual(Operator other) throws FrontendException {
if (other != null && other instanceof CastExpression) {
CastExpression of = (CastExpression)other;
return getExpression().isEqual( of.getExpression() );
} else {
return false;
}
}
@Override
public LogicalSchema.LogicalFieldSchema getFieldSchema() throws FrontendException {
if (fieldSchema!=null)
return fieldSchema;
fieldSchema = new LogicalSchema.LogicalFieldSchema(null, castSchema.schema, castSchema.type);
uidOnlyFieldSchema = fieldSchema.mergeUid(uidOnlyFieldSchema);
// Bring back the top level uid, this is not changed
LogicalExpression exp = (LogicalExpression)plan.getSuccessors(this).get(0);
if (exp.getFieldSchema()!=null) {
fieldSchema.uid = exp.getFieldSchema().uid;
fieldSchema.alias = exp.getFieldSchema().alias;
}
return fieldSchema;
}
@Override
public LogicalExpression deepCopy(LogicalExpressionPlan lgExpPlan) throws FrontendException {
LogicalExpression copy = new CastExpression(
lgExpPlan,
this.getExpression().deepCopy(lgExpPlan),
castSchema.deepCopy());
try {
FuncSpec origFuncSpec = this.getFuncSpec();
if (origFuncSpec != null ) {
((CastExpression)copy).setFuncSpec(origFuncSpec.clone());
}
} catch(CloneNotSupportedException e) {
e.printStackTrace();
}
copy.setLocation( new SourceLocation( location ) );
return copy;
}
}