/*
* 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.relational;
import java.io.IOException;
import java.sql.Array;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.Iterator;
import java.util.List;
import java.util.NoSuchElementException;
import javax.script.CompiledScript;
import javax.script.ScriptContext;
import javax.script.ScriptException;
import javax.script.SimpleScriptContext;
import org.teiid.api.exception.query.ExpressionEvaluationException;
import org.teiid.client.plan.PlanNode;
import org.teiid.common.buffer.BlockedException;
import org.teiid.common.buffer.BufferManager;
import org.teiid.common.buffer.TupleBatch;
import org.teiid.core.TeiidComponentException;
import org.teiid.core.TeiidProcessingException;
import org.teiid.query.QueryPlugin;
import org.teiid.query.analysis.AnalysisRecord;
import org.teiid.query.eval.Evaluator;
import org.teiid.query.function.FunctionDescriptor;
import org.teiid.query.processor.ProcessorDataManager;
import org.teiid.query.sql.LanguageObject;
import org.teiid.query.sql.lang.ObjectTable;
import org.teiid.query.sql.lang.ObjectTable.ObjectColumn;
import org.teiid.query.util.CommandContext;
/**
* Handles object table processing.
*/
public class ObjectTableNode extends SubqueryAwareRelationalNode {
private static class ReflectiveArrayIterator implements Iterator<Object> {
private int index;
private Object array;
private int length;
ReflectiveArrayIterator(Object array) {
this.array = array;
length = java.lang.reflect.Array.getLength(this.array);
}
@Override
public boolean hasNext() {
return index < length;
}
@Override
public Object next() {
if (index >= length) {
throw new NoSuchElementException();
}
return java.lang.reflect.Array.get(array, index++);
}
}
private static final String TEIID_ROW_NUMBER = "teiid_row_number"; //$NON-NLS-1$
private static final String TEIID_ROW = "teiid_row"; //$NON-NLS-1$
private static final String TEIID_CONTEXT = "teiid_context"; //$NON-NLS-1$
private ObjectTable table;
private List<ObjectColumn> projectedColumns;
//processing state
private int rowCount = 0;
private Object item;
private Iterator<?> result;
private SimpleScriptContext scriptContext;
public ObjectTableNode(int nodeID) {
super(nodeID);
}
@Override
public void initialize(CommandContext context, BufferManager bufferManager,
ProcessorDataManager dataMgr) {
super.initialize(context, bufferManager, dataMgr);
this.scriptContext = new SimpleScriptContext();
}
@Override
public void open() throws TeiidComponentException, TeiidProcessingException {
super.open();
if (table.getScriptEngine() == null) {
table.setScriptEngine(getContext().getMetadata().getScriptEngine(table.getScriptingLanguage()));
}
this.scriptContext.setAttribute(TEIID_CONTEXT, this.getContext(), ScriptContext.ENGINE_SCOPE);
}
@Override
public synchronized void closeDirect() {
if (this.scriptContext != null) {
try {
this.scriptContext.getErrorWriter().flush();
} catch (IOException e) {
}
try {
this.scriptContext.getWriter().flush();
} catch (IOException e) {
}
}
super.closeDirect();
reset();
}
@Override
public void reset() {
super.reset();
item = null;
result = null;
rowCount = 0;
if (this.scriptContext != null) {
this.scriptContext.getBindings(ScriptContext.ENGINE_SCOPE).clear();
}
}
public void setTable(ObjectTable table) {
this.table = table;
}
public void setProjectedColumns(List<ObjectColumn> projectedColumns) {
this.projectedColumns = projectedColumns;
}
@Override
public ObjectTableNode clone() {
ObjectTableNode clone = new ObjectTableNode(getID());
this.copyTo(clone);
clone.setTable(table);
clone.setProjectedColumns(projectedColumns);
return clone;
}
@Override
protected synchronized TupleBatch nextBatchDirect() throws BlockedException,
TeiidComponentException, TeiidProcessingException {
evaluate();
while (!isBatchFull() && result.hasNext()) {
if (item == null) {
item = result.next();
if (item == null) {
continue;
}
rowCount++;
}
addBatchRow(processRow());
}
if (!result.hasNext()) {
terminateBatches();
}
return pullBatch();
}
private void evaluate() throws TeiidComponentException,
ExpressionEvaluationException, BlockedException,
TeiidProcessingException {
if (result != null) {
return;
}
setReferenceValues(this.table);
Evaluator eval = getEvaluator(Collections.emptyMap());
eval.evaluateParameters(this.table.getPassing(), null, scriptContext.getBindings(ScriptContext.ENGINE_SCOPE));
Object value = evalScript(this.table.getCompiledScript(), this.table.getRowScript());
if (value instanceof Iterable<?>) {
result = ((Iterable<?>)value).iterator();
} else if (value instanceof Iterator<?>) {
result = (Iterator<?>)value;
} else if (value != null && value.getClass().isArray()){
result = new ReflectiveArrayIterator(value);
} else if (value instanceof Array) {
try {
result = new ReflectiveArrayIterator(((Array)value).getArray());
} catch (SQLException e) {
throw new TeiidProcessingException(e);
}
} else {
result = Arrays.asList(value).iterator();
}
}
private Object evalScript(CompiledScript compiledScript, String script) throws TeiidProcessingException {
try {
if (compiledScript != null) {
return compiledScript.eval(this.scriptContext);
}
return this.table.getScriptEngine().eval(script, this.scriptContext);
} catch (ScriptException e) {
throw new TeiidProcessingException(QueryPlugin.Event.TEIID31110, e, QueryPlugin.Util.gs(QueryPlugin.Event.TEIID31110, script, e.getMessage()));
}
}
private List<?> processRow() throws ExpressionEvaluationException,
TeiidComponentException, TeiidProcessingException {
List<Object> tuple = new ArrayList<Object>(projectedColumns.size());
this.scriptContext.setAttribute(TEIID_ROW, this.item, ScriptContext.ENGINE_SCOPE);
this.scriptContext.setAttribute(TEIID_ROW_NUMBER, this.rowCount, ScriptContext.ENGINE_SCOPE);
for (ObjectColumn proColumn : projectedColumns) {
Object value = evalScript(proColumn.getCompiledScript(), proColumn.getPath());
if (value == null) {
if (proColumn.getDefaultExpression() != null) {
tuple.add(getEvaluator(Collections.emptyMap()).evaluate(proColumn.getDefaultExpression(), null));
} else {
tuple.add(null);
}
continue;
}
value = FunctionDescriptor.importValue(value, proColumn.getSymbol().getType());
tuple.add(value);
}
item = null;
return tuple;
}
@Override
public Collection<? extends LanguageObject> getObjects() {
return this.table.getPassing();
}
@Override
public PlanNode getDescriptionProperties() {
PlanNode props = super.getDescriptionProperties();
AnalysisRecord.addLanaguageObjects(props, AnalysisRecord.PROP_TABLE_FUNCTION, Arrays.asList(this.table));
return props;
}
}