/*
* JBoss, Home of Professional Open Source.
* See the COPYRIGHT.txt file distributed with this work for information
* regarding copyright ownership. Some portions may be licensed
* to Red Hat, Inc. under one or more contributor license agreements.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301 USA.
*/
package org.teiid.query.processor.xml;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import org.teiid.core.TeiidComponentException;
import org.teiid.core.TeiidProcessingException;
import org.teiid.query.QueryPlugin;
import org.teiid.query.sql.symbol.ElementSymbol;
import org.teiid.query.sql.util.VariableContext;
/**
* A XML context is an object which is passed between all the xml processing instructions.
* context will have all the information possible for the block instructions to execute. It will
* also have access to the parent context, however it will not have information on the sibiling
* blocks.
*/
class XMLContext {
// map between variables and their values
Map resultsMap = new HashMap();
// reference to the parent variable context
XMLContext parentContext;
Map executorMap = new HashMap();
VariableContext variableContext = new VariableContext();
/**
* Constructor for VariableContext.
*/
public XMLContext() {
this.resultsMap = new HashMap();
}
/**
* Constructor for VariableContext.
*/
public XMLContext(XMLContext parent) {
this.resultsMap = new HashMap();
this.parentContext = parent;
this.variableContext.setParentContext(parent.variableContext);
}
public XMLContext getParentContext() {
return this.parentContext;
}
/**
* Get the current row of the given result set
* @param aliasResultName
* @return
*/
public List getCurrentRow(String aliasResultName) throws TeiidComponentException, TeiidProcessingException {
PlanExecutor executor = (PlanExecutor)this.resultsMap.get(aliasResultName);
if (executor == null) {
if (this.parentContext != null) {
return this.parentContext.getCurrentRow(aliasResultName);
}
throw new TeiidComponentException(QueryPlugin.Util.getString("results_not_found", aliasResultName)); //$NON-NLS-1$
}
return executor.currentRow();
}
/**
* Get the next row from the result set given.
* @param aliasResultName
* @return
* @throws TeiidComponentException
*/
public List getNextRow(String aliasResultName) throws TeiidComponentException, TeiidProcessingException {
PlanExecutor executor = (PlanExecutor)this.resultsMap.get(aliasResultName);
if (executor == null) {
if (this.parentContext != null) {
return this.parentContext.getNextRow(aliasResultName);
}
throw new TeiidComponentException(QueryPlugin.Util.getString("results_not_found", aliasResultName)); //$NON-NLS-1$
}
return executor.nextRow();
}
/**
* Register the Result Set with the current context
* @param resultName
* @param id
*/
public void setResultSet(String resultName, PlanExecutor executor) {
this.resultsMap.put(resultName, executor);
}
/**
* Be sure that when removing the results, we do not walk into the parent context
* as there may be another resultset with same name. (recursive condition)
*/
public void removeResultSet(String resultName) throws TeiidComponentException {
PlanExecutor executor = (PlanExecutor)this.resultsMap.remove(resultName);
if (executor != null) {
executor.close();
}
}
/**
* Get the schema elements for the resultset. (note that the alias names only apply to results
* not any thing else)
* @param resultName
* @return
* @throws TeiidComponentException
*/
public List getOutputElements(String resultName) throws TeiidComponentException {
PlanExecutor executor = (PlanExecutor)this.resultsMap.get(resultName);
if (executor == null) {
if (this.parentContext != null) {
return this.parentContext.getOutputElements(resultName);
}
throw new TeiidComponentException(QueryPlugin.Util.getString("results_not_found", resultName)); //$NON-NLS-1$
}
return executor.getOutputElements();
}
/**
* This will return element map containing the current row of all the parent resultset objects.
* @return
*/
public Map getReferenceValues() {
HashMap map = new HashMap();
variableContext.getFlattenedContextMap(map);
return map;
}
/**
* Get a registered plan executor object for the result
* @param resultName
* @return
*/
public PlanExecutor getResultExecutor(String resultName) {
return (PlanExecutor)this.executorMap.get(resultName);
}
/**
* Set a registered plan executor object for the result
* @param resultName
* @param executor
*/
public void setResultExecutor(String resultName, PlanExecutor executor) {
this.executorMap.put(resultName, executor);
}
/**
* Remove registered plan executor object for the result
* @param resultName
*/
public void removeResultExecutor(String resultName) {
this.executorMap.remove(resultName);
}
public VariableContext getVariableContext() {
return variableContext;
}
void setVariableValues(String resultSetName,
List row) throws TeiidComponentException {
List elements = getOutputElements(resultSetName);
for (int index = 0; index < elements.size(); index++) {
ElementSymbol symbol = (ElementSymbol)elements.get(index);
variableContext.setValue(new ElementSymbol(resultSetName + ElementSymbol.SEPARATOR + symbol.getShortName()), row.get(index));
}
}
}