/**
* 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.oodt.xmlps.structs;
//OODT imports
import org.apache.oodt.xmlps.mapping.Mapping;
import org.apache.oodt.xmlps.mapping.MappingField;
import org.apache.oodt.xmlps.mapping.funcs.MappingFunc;
import org.apache.oodt.xmlquery.QueryElement;
import org.apache.oodt.xmlquery.Result;
//JDK imports
import java.io.IOException;
import java.io.InputStream;
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.SQLException;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Vector;
/**
* A {@link Result} that wraps a {@link ResultSet} and returns rows as Strings,
* applying {@link MappingFuncs} if a {@link Mapping} is provided, and appending
* constant fields if a {@link List} of {@link CDEValue}s is provided.
*/
public class CDEResult extends Result {
private static final long serialVersionUID = 1L;
private static final String ROW_TERMINATOR = "$";
private final ResultSet rs;
private final Connection con;
private Mapping mapping;
private List<CDEValue> constValues;
private List<QueryElement> orderedFields;
public CDEResult(ResultSet rs, Connection con) {
this.rs = rs;
this.con = con;
setMimeType("text/plain");
}
public void setOrderedFields(List<QueryElement> orderedFields){
this.orderedFields = orderedFields;
}
public void setMapping(Mapping mapping) {
this.mapping = mapping;
}
public void setConstValues(List<CDEValue> constValues) {
this.constValues = constValues;
}
@Override
public InputStream getInputStream() throws IOException {
if (rs == null || con == null)
throw new IOException("InputStream not ready, ResultSet or Connection is null!");
return new CDEResultInputStream(this);
}
@Override
public long getSize() {
return -1;
}
public void close() throws SQLException {
if (rs != null)
rs.close();
if (con != null)
con.close();
}
public String getNextRowAsString() throws SQLException {
if (rs.next()) {
CDERow row = createCDERow();
if (mapping != null)
applyMappingFuncs(row);
if (this.constValues != null &&
((this.orderedFields == null) ||
(this.orderedFields != null && this.orderedFields.size() == 0))){
addConstValues(row);
}
// if there is some kind of configurable response writer,
// here would be a nice place to put it...
return row.toString() + ROW_TERMINATOR;
}
return null;
}
private CDERow createCDERow() throws SQLException {
CDERow row = new CDERow();
ResultSetMetaData met = rs.getMetaData();
int count = met.getColumnCount();
Map<String, CDEValue> dbValMap = new HashMap<String, CDEValue>();
Map<String, CDEValue> constValMap = cdeListToMap(this.constValues);
List<CDEValue> orderedDbVals = new Vector<CDEValue>();
for (int i = 1; i <= count; i++) {
// since the SQL query was built with "SELECT ${fieldlocalname} as ${fieldname}"
// we know that ResultSet column names equal CDE field names
// and appear in the correct order as well
String fieldLocalColName = met.getColumnLabel(i);
String colValue = rs.getString(i);
CDEValue val = new CDEValue(fieldLocalColName, colValue);
dbValMap.put(fieldLocalColName, val);
orderedDbVals.add(val);
}
// now have the constant values, and the db values, order the row
if(this.orderedFields != null){
for(QueryElement qe: this.orderedFields){
String qeCdeVal = this.mapping.getFieldByLocalName(qe.getValue()).getName();
if(dbValMap.containsKey(qeCdeVal)){
row.getVals().add(dbValMap.get(qeCdeVal));
}
else if(constValMap.containsKey(qeCdeVal)){
row.getVals().add(constValMap.get(qeCdeVal));
}
}
}
else row.getVals().addAll(orderedDbVals);
return row;
}
private void applyMappingFuncs(CDERow row) {
for (CDEValue value : row.getVals()) {
MappingField fld = mapping.getFieldByName(value.getCdeName());
if (fld != null) {
for (MappingFunc func : fld.getFuncs()) {
CDEValue newValue = func.translate(value);
value.setVal(newValue.getVal());
}
}
}
}
private void addConstValues(CDERow row) {
row.getVals().addAll(constValues);
}
private Map<String, CDEValue> cdeListToMap(List<CDEValue> vals){
Map<String, CDEValue> map = new HashMap<String, CDEValue>();
if(vals != null){
for(CDEValue val: vals){
map.put(val.getCdeName(), val);
}
}
return map;
}
}