/*
* 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.solr.client.solrj.io.stream;
import java.io.IOException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import org.apache.solr.client.solrj.io.Tuple;
import org.apache.solr.client.solrj.io.comp.StreamComparator;
import org.apache.solr.client.solrj.io.stream.expr.Explanation;
import org.apache.solr.client.solrj.io.stream.expr.Explanation.ExpressionType;
import org.apache.solr.client.solrj.io.stream.expr.Expressible;
import org.apache.solr.client.solrj.io.stream.expr.StreamExplanation;
import org.apache.solr.client.solrj.io.stream.expr.StreamExpression;
import org.apache.solr.client.solrj.io.stream.expr.StreamFactory;
public class GetStream extends TupleStream implements Expressible {
private static final long serialVersionUID = 1;
private StreamContext streamContext;
private String name;
private Iterator<Tuple> tupleIterator;
public GetStream(String name) throws IOException {
init(name);
}
public GetStream(StreamExpression expression, StreamFactory factory) throws IOException {
String name = factory.getValueOperand(expression, 0);
init(name);
}
private void init(String name) {
this.name = name;
}
@Override
public StreamExpression toExpression(StreamFactory factory) throws IOException{
return toExpression(factory, true);
}
private StreamExpression toExpression(StreamFactory factory, boolean includeStreams) throws IOException {
// function name
StreamExpression expression = new StreamExpression(factory.getFunctionName(this.getClass()));
expression.addParameter(name);
return expression;
}
@Override
public Explanation toExplanation(StreamFactory factory) throws IOException {
StreamExplanation explanation = new StreamExplanation(getStreamNodeId().toString());
explanation.setFunctionName(factory.getFunctionName(this.getClass()));
explanation.setImplementingClass(this.getClass().getName());
explanation.setExpressionType(ExpressionType.STREAM_SOURCE);
explanation.setExpression(toExpression(factory, false).toString());
return explanation;
}
public void setStreamContext(StreamContext context) {
this.streamContext = context;
}
public List<TupleStream> children() {
List<TupleStream> l = new ArrayList();
return l;
}
public Tuple read() throws IOException {
Map map = new HashMap();
if(tupleIterator.hasNext()) {
Tuple t = tupleIterator.next();
map.putAll(t.fields);
return new Tuple(map);
} else {
map.put("EOF", true);
return new Tuple(map);
}
}
public void close() throws IOException {
}
public void open() throws IOException {
Map<String, Object> lets = streamContext.getLets();
Object o = lets.get(name);
List l = null;
if(o instanceof List) {
l = (List)o;
if(l.get(0) instanceof Tuple) {
tupleIterator = l.iterator();
} else {
throw new IOException("Get was not passed a list of tuples:"+o.getClass());
}
}
}
/** Return the stream sort - ie, the order in which records are returned */
public StreamComparator getStreamSort(){
return null;
}
public int getCost() {
return 0;
}
}