/*
* 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.openjpa.jdbc.kernel;
import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import org.apache.openjpa.jdbc.meta.ClassMapping;
import org.apache.openjpa.jdbc.meta.FieldMapping;
import org.apache.openjpa.jdbc.meta.MappingRepository;
import org.apache.openjpa.jdbc.schema.Column;
import org.apache.openjpa.jdbc.sql.LogicalUnion;
import org.apache.openjpa.jdbc.sql.SQLBuffer;
import org.apache.openjpa.jdbc.sql.SelectExecutor;
import org.apache.openjpa.jdbc.sql.SelectImpl;
import org.apache.openjpa.jdbc.sql.Union;
import org.apache.openjpa.kernel.Broker;
import org.apache.openjpa.kernel.PreparedQuery;
import org.apache.openjpa.kernel.Query;
import org.apache.openjpa.kernel.QueryImpl;
import org.apache.openjpa.kernel.QueryLanguages;
import org.apache.openjpa.kernel.StoreQuery;
import org.apache.openjpa.kernel.PreparedQueryCache.Exclusion;
import org.apache.openjpa.kernel.exps.QueryExpressions;
import org.apache.openjpa.lib.rop.RangeResultObjectProvider;
import org.apache.openjpa.lib.rop.ResultList;
import org.apache.openjpa.lib.util.Localizer;
import org.apache.openjpa.meta.FieldMetaData;
import org.apache.openjpa.util.ImplHelper;
import org.apache.openjpa.util.InternalException;
import org.apache.openjpa.util.UserException;
/**
* Implements {@link PreparedQuery} for SQL queries.
* PreparedQuery holds the post-compilation and post-execution state of a kernel Query.
* The post-execution internal state of a query is appended as a <em>user object</em>
* to the user-visible result to maintain the API contract.
*
* @author Pinaki Poddar
*
*/
public class PreparedQueryImpl implements PreparedQuery {
private static Localizer _loc =
Localizer.forPackage(PreparedQueryImpl.class);
private final String _id;
private String _sql;
private boolean _initialized;
// Post-compilation state of an executable query, populated on construction
private Class<?> _candidate;
private boolean _subclasses;
// post-execution state of a query
private QueryExpressions[] _exps;
private Class<?>[] _projTypes;
// Position of the user defined parameters in the _params list
private Map<Object, int[]> _userParamPositions;
private Map<Integer, Object> _template;
private SelectImpl select;
/**
* Construct.
*
* @param id an identifier for this query to be used as cache key
* @param compiled a compiled query
*/
public PreparedQueryImpl(String id, Query compiled) {
this(id, null, compiled);
}
/**
* Construct.
*
* @param id an identifier for this query to be used as cache key
* @param corresponding data store language query string
* @param compiled a compiled query
*/
public PreparedQueryImpl(String id, String sql, Query compiled) {
this._id = id;
this._sql = sql;
if (compiled != null) {
_candidate = compiled.getCandidateType();
_subclasses = compiled.hasSubclasses();
}
}
public String getIdentifier() {
return _id;
}
public String getLanguage() {
return QueryLanguages.LANG_PREPARED_SQL;
}
/**
* Get the original query string which is same as the identifier of this
* receiver.
*/
public String getOriginalQuery() {
return getIdentifier();
}
public String getTargetQuery() {
return _sql;
}
void setTargetQuery(String sql) {
_sql = sql;
}
public boolean isInitialized() {
return _initialized;
}
public QueryExpressions[] getQueryExpressions() {
return _exps;
}
public Class[] getProjectionTypes() {
return _projTypes;
}
/**
* Pours the post-compilation state held by this receiver to the given
* query.
*/
public void setInto(Query q) {
q.setQuery(_id);
q.setCandidateType(_candidate, _subclasses);
}
/**
* Initialize this receiver with post-execution result.
* The input argument is processed only if it is a {@link ResultList} with
* an attached {@link SelectResultObjectProvider} as its
* {@link ResultList#getUserObject() user object}.
*
* @return an exclusion if can not be initialized for some reason.
* null if initialization is successful.
*/
public Exclusion initialize(Object result) {
if (isInitialized())
return null;
Object[] extract = extractSelectExecutor(result);
SelectExecutor selector = (SelectExecutor)extract[0];
if (selector == null)
return new PreparedQueryCacheImpl.StrongExclusion(_id, ((Localizer.Message)extract[1]).getMessage());
if (selector == null || selector.hasMultipleSelects()
|| ((selector instanceof Union)
&& (((Union)selector).getSelects().length != 1)))
return new PreparedQueryCacheImpl.StrongExclusion(_id, _loc.get("exclude-multi-select", _id).getMessage());
select = extractImplementation(selector);
if (select == null)
return new PreparedQueryCacheImpl.StrongExclusion(_id, _loc.get("exclude-no-select", _id).getMessage());
SQLBuffer buffer = selector.getSQL();
if (buffer == null)
return new PreparedQueryCacheImpl.StrongExclusion(_id, _loc.get("exclude-no-sql", _id).getMessage());;
if (isUsingFieldStrategy())
return new PreparedQueryCacheImpl.StrongExclusion(_id,
_loc.get("exclude-user-strategy", _id).getMessage());;
if (isPaginated())
return new PreparedQueryCacheImpl.StrongExclusion(_id,
_loc.get("exclude-pagination", _id).getMessage());;
setTargetQuery(buffer.getSQL());
setParameters(buffer.getParameters());
setUserParameterPositions(buffer.getUserParameters());
_initialized = true;
return null;
}
/**
* Extract the underlying SelectExecutor from the given argument, if possible.
*
* @return two objects in an array. The element at index 0 is SelectExecutor,
* if it can be extracted. The element at index 1 is the reason why it can
* not be extracted.
*/
private Object[] extractSelectExecutor(Object result) {
if (result instanceof ResultList == false)
return new Object[]{null, _loc.get("exclude-not-result", _id)};
Object userObject = ((ResultList<?>)result).getUserObject();
if (userObject == null || !userObject.getClass().isArray() || ((Object[])userObject).length != 2)
return new Object[]{null, _loc.get("exclude-no-user-object", _id)};
Object provider = ((Object[])userObject)[0];
Object executor = ((Object[])userObject)[1];
if (executor instanceof StoreQuery.Executor == false)
return new Object[]{null, _loc.get("exclude-not-executor", _id)};
_exps = ((StoreQuery.Executor)executor).getQueryExpressions();
for (int i = 0; i < _exps.length; i++) {
if (isUsingExternalizedParameter(_exps[i])) {
return new Object[]{null, _loc.get("exclude-externalized-param", _id)};
}
}
if (_exps[0].projections.length == 0) {
_projTypes = StoreQuery.EMPTY_CLASSES;
} else {
_projTypes = new Class[_exps[0].projections.length];
for (int i = 0; i < _exps[0].projections.length; i++) {
_projTypes[i] = _exps[0].projections[i].getType();
}
}
if (provider instanceof QueryImpl.PackingResultObjectProvider) {
provider = ((QueryImpl.PackingResultObjectProvider)provider).getDelegate();
}
if (provider instanceof RangeResultObjectProvider) {
provider = ((RangeResultObjectProvider)provider).getDelegate();
}
if (provider instanceof SelectResultObjectProvider) {
return new Object[]{((SelectResultObjectProvider)provider).getSelect(), null};
}
return new Object[]{null, _loc.get("exclude-not-select-rop", _id, provider.getClass().getName())};
}
private SelectImpl extractImplementation(SelectExecutor selector) {
if (selector == null)
return null;
if (selector instanceof SelectImpl)
return (SelectImpl)selector;
if (selector instanceof LogicalUnion.UnionSelect)
return ((LogicalUnion.UnionSelect)selector).getDelegate();
if (selector instanceof Union)
return extractImplementation(((Union)selector).getSelects()[0]);
return null;
}
private boolean isUsingExternalizedParameter(QueryExpressions exp) {
if (exp == null)
return false;
List<FieldMetaData> fmds = exp.getParameterizedFields();
if (fmds == null || fmds.isEmpty())
return false;
for (FieldMetaData fmd : fmds) {
if (fmd.isExternalized())
return true;
}
return false;
}
private boolean isPaginated() {
if (select instanceof SelectImpl) {
if (((SelectImpl)select).getStartIndex() != 0 ||
((SelectImpl)select).getEndIndex() != Long.MAX_VALUE)
return true;
}
return false;
}
private boolean isUsingFieldStrategy() {
for (int i = 0; i < _exps.length; i++) {
if (isUsingFieldStrategy(_exps[i])) {
return true;
}
}
return false;
}
private boolean isUsingFieldStrategy(QueryExpressions exp) {
if (exp == null)
return false;
List<FieldMetaData> fmds = exp.getParameterizedFields();
if (fmds == null || fmds.isEmpty())
return false;
for (FieldMetaData fmd : fmds) {
if (((FieldMapping)fmd).getMappingInfo().getStrategy() != null)
return true;
}
return false;
}
/**
* Merge the given user parameters with its own parameter. The given map
* must be compatible with the user parameters extracted during
* {@link #initialize(Object) initialization}.
*
* @return 0-based parameter index mapped to corresponding values.
*
*/
public Map<Integer, Object> reparametrize(Map user, Broker broker) {
if (!isInitialized())
throw new InternalException("reparameterize() on uninitialized.");
if (user == null || user.isEmpty()) {
if (!_userParamPositions.isEmpty()) {
throw new UserException(_loc.get("uparam-null",
_userParamPositions.keySet(), this));
} else {
return _template;
}
}
if (!_userParamPositions.keySet().equals(user.keySet())) {
throw new UserException(_loc.get("uparam-mismatch",
_userParamPositions.keySet(), user.keySet(), this));
}
Map<Integer, Object> result = new HashMap<Integer, Object>(_template);
for (Object key : user.keySet()) {
int[] indices = _userParamPositions.get(key);
if (indices == null || indices.length == 0)
throw new UserException(_loc.get("uparam-no-pos", key, this));
Object val = user.get(key);
if (ImplHelper.isManageable(val)) {
setPersistenceCapableParameter(result, val, indices, broker);
} else if (val instanceof Collection) {
setCollectionValuedParameter(result, (Collection)val, indices,
key);
} else {
for (int j : indices) {
if (val instanceof Enum) {
if (_template.get(j) instanceof Integer) {
val = ((Enum)val).ordinal();
} else {
val = ((Enum)val).name();
}
}
result.put(j, val);
}
}
}
return result;
}
/**
* Calculate primary key identity value(s) of the given manageable instance
* and fill in the given map.
*
* @param values a map of integer parameter index to parameter value
* @param pc a manageable instance
* @param indices the indices of the column values
* @param broker used to obtain the primary key values
*/
private void setPersistenceCapableParameter(Map<Integer,Object> result,
Object pc, int[] indices, Broker broker) {
JDBCStore store = (JDBCStore)broker.getStoreManager()
.getInnermostDelegate();
MappingRepository repos = store.getConfiguration()
.getMappingRepositoryInstance();
ClassMapping mapping = repos.getMapping(pc.getClass(),
broker.getClassLoader(), true);
Column[] pks = mapping.getPrimaryKeyColumns();
Object cols = mapping.toDataStoreValue(pc, pks, store);
if (cols instanceof Object[]) {
Object[] array = (Object[])cols;
int n = array.length;
if (n > indices.length || indices.length%n != 0)
throw new UserException(_loc.get("uparam-pc-key",
pc.getClass(), n, Arrays.toString(indices)));
int k = 0;
for (int j : indices) {
result.put(j, array[k%n]);
k++;
}
} else {
for (int j : indices) {
result.put(j, cols);
}
}
}
private void setCollectionValuedParameter(Map<Integer,Object> result,
Collection values, int[] indices, Object param) {
int n = values.size();
Object[] array = values.toArray();
if (n > indices.length || indices.length%n != 0) {
throw new UserException(_loc.get("uparam-coll-size", param, values,
Arrays.toString(indices)));
}
int k = 0;
for (int j : indices) {
result.put(j, array[k%n]);
k++;
}
}
/**
* Marks the positions and keys of user parameters.
*
* @param list even elements are numbers representing the position of a
* user parameter in the _param list. Odd elements are the user parameter
* key. A user parameter key may appear more than once.
*/
void setUserParameterPositions(List list) {
_userParamPositions = new HashMap<Object, int[]>();
for (int i = 1; list != null && i < list.size(); i += 2) {
Object key = list.get(i);
int p = (Integer)list.get(i-1);
int[] positions = _userParamPositions.get(key);
if (positions == null) {
positions = new int[]{p};
} else {
int[] temp = new int[positions.length+1];
System.arraycopy(positions, 0, temp, 0, positions.length);
temp[positions.length] = p;
positions = temp;
}
_userParamPositions.put(key, positions);
}
}
void setParameters(List list) {
Map<Integer, Object> tmp = new HashMap<Integer, Object>();
for (int i = 0; list != null && i < list.size(); i++) {
tmp.put(i, list.get(i));
}
_template = Collections.unmodifiableMap(tmp);
}
SelectImpl getSelect() {
return select;
}
public String toString() {
return "PreparedQuery: [" + getOriginalQuery() + "] --> [" +
getTargetQuery() + "]";
}
}