/*
* Copyright (c) 2013, OpenCloudDB/MyCAT and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software;Designed and Developed mainly by many Chinese
* opensource volunteers. you can redistribute it and/or modify it under the
* terms of the GNU General Public License version 2 only, as published by the
* Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Any questions about this component can be directed to it's project Web address
* https://code.google.com/p/opencloudb/.
*
*/
package com.akiban.sql.parser;
import com.akiban.sql.StandardException;
/**
* A TableOperatorNode represents a relational operator like UNION, INTERSECT,
* JOIN, etc. that takes two tables as parameters and returns a table. The
* parameters it takes are represented as ResultSetNodes.
*
* Currently, all known table operators are binary operators, so there are no
* subclasses of this node type called "BinaryTableOperatorNode" and
* "UnaryTableOperatorNode".
*
*/
abstract class TableOperatorNode extends FromTable
{
protected ResultSetNode leftResultSet;
protected ResultSetNode rightResultSet;
/**
* Initializer for a TableOperatorNode.
*
* @param leftResultSet The ResultSetNode on the left side of this node
* @param rightResultSet The ResultSetNode on the right side of this node
* @param tableProperties Properties list associated with the table
*
* @exception StandardException Thrown on error
*/
public void init(Object leftResultSet,
Object rightResultSet,
Object tableProperties)
throws StandardException {
/* correlationName is always null */
init(null, tableProperties);
this.leftResultSet = (ResultSetNode)leftResultSet;
this.rightResultSet = (ResultSetNode)rightResultSet;
}
/**
* Fill this node with a deep copy of the given node.
*/
public void copyFrom(QueryTreeNode node) throws StandardException {
super.copyFrom(node);
TableOperatorNode other = (TableOperatorNode)node;
this.leftResultSet = (ResultSetNode)getNodeFactory().copyNode(other.leftResultSet,
getParserContext());
this.rightResultSet = (ResultSetNode)getNodeFactory().copyNode(other.rightResultSet,
getParserContext());
}
/**
* Convert this object to a String. See comments in QueryTreeNode.java
* for how this should be done for tree printing.
*
* @return This object as a String
*/
public String toString() {
return "nestedInParens: " + false + "\n" +
super.toString();
}
/**
* Prints the sub-nodes of this object. See QueryTreeNode.java for
* how tree printing is supposed to work.
*
* @param depth The depth of this node in the tree
*/
public void printSubNodes(int depth) {
super.printSubNodes(depth);
if (leftResultSet != null) {
printLabel(depth, "leftResultSet: ");
leftResultSet.treePrint(depth + 1);
}
if (rightResultSet != null) {
printLabel(depth, "rightResultSet: ");
rightResultSet.treePrint(depth + 1);
}
}
/**
* Get the leftResultSet from this node.
*
* @return ResultSetNode The leftResultSet from this node.
*/
public ResultSetNode getLeftResultSet() {
return leftResultSet;
}
/**
* Get the rightResultSet from this node.
*
* @return ResultSetNode The rightResultSet from this node.
*/
public ResultSetNode getRightResultSet() {
return rightResultSet;
}
public void setLeftResultSet(ResultSetNode leftResultSet) {
this.leftResultSet = leftResultSet;
}
public void setRightResultSet(ResultSetNode rightResultSet) {
this.rightResultSet = rightResultSet;
}
public ResultSetNode getLeftmostResultSet() {
if (leftResultSet instanceof TableOperatorNode) {
return ((TableOperatorNode)leftResultSet).getLeftmostResultSet();
}
else {
return leftResultSet;
}
}
public void setLeftmostResultSet(ResultSetNode newLeftResultSet) {
if (leftResultSet instanceof TableOperatorNode) {
((TableOperatorNode)leftResultSet).setLeftmostResultSet(newLeftResultSet);
}
else {
this.leftResultSet = newLeftResultSet;
}
}
/**
* Return the exposed name for this table, which is the name that
* can be used to refer to this table in the rest of the query.
*
* @return The exposed name for this table.
*/
public String getExposedName() {
return null;
}
/**
* Mark whether or not this node is nested in parens. (Useful to parser
* since some trees get created left deep and others right deep.)
* The resulting state of this cal was never used so its
* field was removed to save runtimespace for this node.
* Further cleanup can be done including parser changes
* if this call is really nor required.
*
* @param nestedInParens Whether or not this node is nested in parens.
*/
public void setNestedInParens(boolean nestedInParens) {
}
/**
* Accept the visitor for all visitable children of this node.
*
* @param v the visitor
*
* @exception StandardException on error
*/
void acceptChildren(Visitor v) throws StandardException {
super.acceptChildren(v);
if (leftResultSet != null) {
leftResultSet = (ResultSetNode)leftResultSet.accept(v);
}
if (rightResultSet != null) {
rightResultSet = (ResultSetNode)rightResultSet.accept(v);
}
}
}