timestampoperatornode.java

derby database source code.good for you.

/*

   Derby - Class org.apache.derby.impl.sql.compile.TimestampOperatorNode

   Copyright 2004 The Apache Software Foundation or its licensors, as applicable.

   Licensed 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.derby.impl.sql.compile;

import org.apache.derby.iapi.types.TypeId;
import org.apache.derby.iapi.types.DataValueFactory;
import org.apache.derby.iapi.types.DataTypeDescriptor;
import org.apache.derby.iapi.services.compiler.MethodBuilder;
import org.apache.derby.iapi.error.StandardException;

import org.apache.derby.impl.sql.compile.ExpressionClassBuilder;

import org.apache.derby.iapi.reference.ClassName;
import org.apache.derby.iapi.reference.SQLState;

import org.apache.derby.iapi.services.classfile.VMOpcode;

import java.sql.Types;

import java.util.Vector;

/**
 * The TimestampOperatorNode class implements the timestamp( date, time) function.
 */

public class TimestampOperatorNode extends BinaryOperatorNode
{

    /**
     * Initailizer for a TimestampOperatorNode.
     *
     * @param date The date
     * @param time The time
     */

    public void init( Object date,
                      Object time)
    {
        leftOperand = (ValueNode) date;
        rightOperand = (ValueNode) time;
        operator = "timestamp";
        methodName = "getTimestamp";
    }


	/**
	 * Bind this expression.  This means binding the sub-expressions,
	 * as well as figuring out what the return type is for this expression.
	 *
	 * @param fromList		The FROM list for the query this
	 *				expression is in, for binding columns.
	 * @param subqueryList		The subquery list being built as we find SubqueryNodes
	 * @param aggregateVector	The aggregate vector being built as we find AggregateNodes
	 *
	 * @return	The new top of the expression tree.
	 *
	 * @exception StandardException		Thrown on error
	 */

	public ValueNode bindExpression(
		FromList fromList, SubqueryList subqueryList,
		Vector	aggregateVector) 
			throws StandardException
	{
		leftOperand = leftOperand.bindExpression(fromList, subqueryList, 
			aggregateVector);
		rightOperand = rightOperand.bindExpression(fromList, subqueryList, 
			aggregateVector);

        TypeId leftTypeId = leftOperand.getTypeId();
        TypeId rightTypeId = rightOperand.getTypeId();
        if( !(leftTypeId.isStringTypeId() || leftTypeId.getJDBCTypeId() == Types.DATE || leftOperand.isParameterNode()))
            throw StandardException.newException(SQLState.LANG_BINARY_OPERATOR_NOT_SUPPORTED, 
                                                 operator, leftTypeId.getSQLTypeName(), rightTypeId.getSQLTypeName());
        if( !(rightTypeId.isStringTypeId() || rightTypeId.getJDBCTypeId() == Types.TIME || rightOperand.isParameterNode()))
            throw StandardException.newException(SQLState.LANG_BINARY_OPERATOR_NOT_SUPPORTED, 
                                                 operator, leftTypeId.getSQLTypeName(), rightTypeId.getSQLTypeName());
        setType(DataTypeDescriptor.getBuiltInDataTypeDescriptor( Types.TIMESTAMP));
		return genSQLJavaSQLTree();
	} // end of bindExpression

    /**
	 * Do code generation for this binary operator.
	 *
	 * @param acb	The ExpressionClassBuilder for the class we're generating
	 * @param mb	The method the code to place the code
	 *
	 *
	 * @exception StandardException		Thrown on error
	 */

	public void generateExpression(ExpressionClassBuilder acb,
											MethodBuilder mb)
		throws StandardException
	{
        acb.pushDataValueFactory(mb);
		leftOperand.generateExpression(acb, mb);
        mb.cast( ClassName.DataValueDescriptor);
		rightOperand.generateExpression(acb, mb);
        mb.cast( ClassName.DataValueDescriptor);
        mb.callMethod( VMOpcode.INVOKEINTERFACE, null, methodName, ClassName.DateTimeDataValue, 2);
    } // end of generateExpression
}