org.apache.pig.backend.hadoop.executionengine.physicalLayer.expressionOperators.EqualToExpr.java Source code

Introduction

Here is the source code for org.apache.pig.backend.hadoop.executionengine.physicalLayer.expressionOperators.EqualToExpr.java

Source

/*
 * 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.backend.hadoop.executionengine.physicalLayer.expressionOperators;

import java.util.HashMap;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.pig.PigException;
import org.apache.pig.backend.executionengine.ExecException;
import org.apache.pig.backend.hadoop.executionengine.physicalLayer.POStatus;
import org.apache.pig.backend.hadoop.executionengine.physicalLayer.Result;
import org.apache.pig.backend.hadoop.executionengine.physicalLayer.plans.PhyPlanVisitor;
import org.apache.pig.data.DataType;
import org.apache.pig.impl.plan.NodeIdGenerator;
import org.apache.pig.impl.plan.OperatorKey;
import org.apache.pig.impl.plan.VisitorException;

public class EqualToExpr extends BinaryComparisonOperator {

    /**
     *
     */
    private static final long serialVersionUID = 1L;
    transient private final Log log = LogFactory.getLog(getClass());

    public EqualToExpr(OperatorKey k) {
        this(k, -1);
    }

    public EqualToExpr(OperatorKey k, int rp) {
        super(k, rp);
        resultType = DataType.BOOLEAN;
    }

    @Override
    public String name() {
        return "Equal To" + "[" + DataType.findTypeName(resultType) + "]" + " - " + mKey.toString();
    }

    @Override
    public void visit(PhyPlanVisitor v) throws VisitorException {
        v.visitEqualTo(this);
    }

    @Override
    public Result getNextBoolean() throws ExecException {
        try {
            Result left, right;

            switch (operandType) {
            case DataType.BYTEARRAY:
            case DataType.DOUBLE:
            case DataType.FLOAT:
            case DataType.BOOLEAN:
            case DataType.INTEGER:
            case DataType.BIGINTEGER:
            case DataType.BIGDECIMAL:
            case DataType.LONG:
            case DataType.DATETIME:
            case DataType.CHARARRAY:
            case DataType.TUPLE:
            case DataType.MAP: {
                Result r = accumChild(null, operandType);
                if (r != null) {
                    return r;
                }
                left = lhs.getNext(operandType);
                right = rhs.getNext(operandType);
                return doComparison(left, right);
            }

            default: {
                int errCode = 2067;
                String msg = this.getClass().getSimpleName() + " does not know how to " + "handle type: "
                        + DataType.findTypeName(operandType);
                throw new ExecException(msg, errCode, PigException.BUG);
            }

            }
        } catch (RuntimeException e) {
            throw new ExecException("exception while executing " + this.toString() + ": " + e.toString(), 2067,
                    PigException.BUG, e);
        }
    }

    @SuppressWarnings("unchecked")
    private Result doComparison(Result left, Result right) throws ExecException {
        if (left.returnStatus != POStatus.STATUS_OK) {
            return left;
        }
        if (right.returnStatus != POStatus.STATUS_OK) {
            return right;
        }
        // if either operand is null, the result should be
        // null
        if (left.result == null || right.result == null) {
            left.result = null;
            left.returnStatus = POStatus.STATUS_OK;
            return left;
        }

        if (left.result instanceof Comparable && right.result instanceof Comparable) {
            if (((Comparable) left.result).compareTo(right.result) == 0) {
                left.result = Boolean.TRUE;
            } else {
                left.result = Boolean.FALSE;
            }
        } else if (left.result instanceof HashMap && right.result instanceof HashMap) {
            HashMap leftMap = (HashMap) left.result;
            HashMap rightMap = (HashMap) right.result;
            if (leftMap.equals(rightMap)) {
                left.result = Boolean.TRUE;
            } else {
                left.result = Boolean.FALSE;
            }
        } else {
            throw new ExecException("The left side and right side has the different types");
        }
        illustratorMarkup(null, left.result, (Boolean) left.result ? 0 : 1);
        return left;
    }

    @Override
    public EqualToExpr clone() throws CloneNotSupportedException {
        EqualToExpr clone = new EqualToExpr(
                new OperatorKey(mKey.scope, NodeIdGenerator.getGenerator().getNextNodeId(mKey.scope)));
        clone.cloneHelper(this);
        return clone;
    }
}