/*
* Copyright 2014 mango.concurrent.cc
*
* The Netty Project 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 cc.concurrent.mango.runtime.operator;
import cc.concurrent.mango.exception.IncorrectReturnTypeException;
import cc.concurrent.mango.exception.IncorrectSqlException;
import cc.concurrent.mango.exception.NotReadablePropertyException;
import cc.concurrent.mango.exception.UnreachableCodeException;
import cc.concurrent.mango.jdbc.BeanPropertyRowMapper;
import cc.concurrent.mango.jdbc.JdbcUtils;
import cc.concurrent.mango.jdbc.RowMapper;
import cc.concurrent.mango.jdbc.SingleColumnRowMapper;
import cc.concurrent.mango.runtime.ParsedSql;
import cc.concurrent.mango.runtime.RuntimeContext;
import cc.concurrent.mango.runtime.TypeContext;
import cc.concurrent.mango.runtime.parser.ASTIterableParameter;
import cc.concurrent.mango.runtime.parser.ASTRootNode;
import cc.concurrent.mango.util.ArrayUtil;
import cc.concurrent.mango.util.Iterables;
import cc.concurrent.mango.util.TypeToken;
import cc.concurrent.mango.util.logging.InternalLogger;
import cc.concurrent.mango.util.logging.InternalLoggerFactory;
import cc.concurrent.mango.util.reflect.BeanInfoCache;
import cc.concurrent.mango.util.reflect.BeanUtil;
import java.lang.reflect.Method;
import java.util.*;
/**
* 处理所有的查询操作
*
* @author ash
*/
public class QueryOperator extends CacheableOperator {
private final static InternalLogger logger = InternalLoggerFactory.getInstance(QueryOperator.class);
private ASTRootNode rootNode;
private RowMapper<?> rowMapper;
private Class<?> mappedClass;
private boolean isForList;
private boolean isForSet;
private boolean isForArray;
private String interableProperty; // "a in (:1)"中的a
private QueryOperator(ASTRootNode rootNode, Method method, SQLType sqlType) {
super(method, sqlType);
init(rootNode, method);
}
private void init(ASTRootNode rootNode, Method method) {
this.rootNode = rootNode;
TypeToken typeToken = new TypeToken(method.getGenericReturnType());
isForList = typeToken.isList();
isForSet = typeToken.isSet();
isForArray = typeToken.isArray();
mappedClass = typeToken.getMappedClass();
rowMapper = getRowMapper(mappedClass);
TypeContext context = buildTypeContext(method.getGenericParameterTypes());
rootNode.checkType(context); // 检测sql中的参数是否和方法上的参数匹配
checkCacheBy(rootNode); // 如果使用cache，检测cache参数
List<ASTIterableParameter> aips = rootNode.getASTIterableParameters();
if (!aips.isEmpty() && !isForList && !isForSet && !isForArray) {
throw new IncorrectReturnTypeException("if sql has in clause, return type " +
"expected array or implementations of java.util.List or implementations of java.util.Set " +
"but " + method.getGenericReturnType()); // sql中使用了in查询，返回参数必须可迭代
}
if (isUseCache()) {
if (aips.size() == 1) {
interableProperty = aips.get(0).getInterableProperty();
Method readMethod = BeanInfoCache.getReadMethod(mappedClass, interableProperty);
if (readMethod == null) {
// 如果使用cache并且sql中有一个in语句，mappedClass必须含有特定属性，必须a in (...)，则mappedClass必须含有a属性
throw new NotReadablePropertyException("if use cache and sql has one in clause, property "
+ interableProperty + " of " + mappedClass + " expected readable but not");
}
} else if (aips.size() != 0) {
throw new IncorrectSqlException("if use cache, sql's in clause expected less than or equal 1 but "
+ aips.size()); // 如果使用cache，sql中的in语句不能超过1
}
}
}
public static QueryOperator create(ASTRootNode rootNode, Method method, SQLType sqlType) {
return new QueryOperator(rootNode, method, sqlType);
}
@Override
public Object execute(Object[] methodArgs) {
RuntimeContext context = buildRuntimeContext(methodArgs);
if (isUseCache()) { // 先使用缓存，再使用db
return executeFromCache(context);
} else { // 直接使用db
return executeFromDb(context, rowMapper);
}
}
private Object executeFromCache(RuntimeContext context) {
Object obj = getCacheKeyObj(context);
Iterables iterables = new Iterables(obj);
if (iterables.isIterable()) { // 多个key
Set<String> keys = new HashSet<String>();
Class<?> keyObjClass = null;
for (Object keyObj : iterables) {
String key = getKey(keyObj);
keys.add(key);
if (keyObjClass == null) {
keyObjClass = keyObj.getClass();
}
}
return multipleKeysCache(context, iterables, keys, rowMapper.getMappedClass(), keyObjClass);
} else { // 单个key
String key = getKey(obj);
return singleKeyCache(context, key);
}
}
private <T, U> Object multipleKeysCache(RuntimeContext context, Iterables keyObjIterables, Set<String> keys,
Class<T> valueClass, Class<U> keyObjClass) {
boolean isDebugEnabled = logger.isDebugEnabled();
Map<String, Object> map = getBulkFromCache(keys);
int initialCapacity = Math.max(1, map != null ? map.size() : 0);
AddableObject<T> addableObj = new AddableObject<T>(initialCapacity, valueClass);
List<U> hitKeyObjs = new ArrayList<U>(); // 用于debug
Set<U> missKeyObjs = new HashSet<U>();
for (Object keyObj : keyObjIterables) {
String key = getKey(keyObj);
Object value = map != null ? map.get(key) : null;
if (value == null) {
missKeyObjs.add(keyObjClass.cast(keyObj));
} else {
addableObj.add(valueClass.cast(value));
if (isDebugEnabled) {
hitKeyObjs.add(keyObjClass.cast(keyObj));
}
}
}
if (isDebugEnabled) {
logger.debug("cache hit #keys={} #values={}", hitKeyObjs, addableObj);
logger.debug("cache miss #keys={}", missKeyObjs);
}
if (!missKeyObjs.isEmpty()) { // 有key没有命中
context.setPropertyValue(getCacheParameterName(), getCachePropertyPath(), missKeyObjs);
Object dbValues = executeFromDb(context, rowMapper);
for (Object dbValue : new Iterables(dbValues)) {
// db数据添加入结果
addableObj.add(valueClass.cast(dbValue));
// 添加入缓存
Object keyObj = BeanUtil.getPropertyValue(dbValue, interableProperty, mappedClass);
String key = getKey(keyObj);
setToCache(key, dbValue);
}
}
return addableObj.getReturn();
}
private Object singleKeyCache(RuntimeContext context, String key) {
Object value = getFromCache(key);
if (value == null) {
if (logger.isDebugEnabled()) {
logger.debug("cache miss #key＝{}", key);
}
value = executeFromDb(context, rowMapper);
if (value != null) {
setToCache(key, value);
if (logger.isDebugEnabled()) {
logger.debug("cache set #key={} #value={}", key, value);
}
}
} else {
if (logger.isDebugEnabled()) {
logger.debug("cache hit #key={} #value={}", key, value);
}
}
return value;
}
private <T> Object executeFromDb(RuntimeContext context, RowMapper<T> rowMapper) {
ParsedSql parsedSql = rootNode.buildSqlAndArgs(context);
String sql = parsedSql.getSql();
Object[] args = parsedSql.getArgs();
if (logger.isDebugEnabled()) {
logger.debug("{} #args={}", sql, args);
}
if (isForList) {
List<T> list = jdbcTemplate.queryForList(getDataSource(), sql, args, rowMapper);
if (logger.isDebugEnabled()) {
logger.debug("{} #result={}", sql, list);
}
return list;
} else if (isForSet) {
Set<T> set = jdbcTemplate.queryForSet(getDataSource(), sql, args, rowMapper);
if (logger.isDebugEnabled()) {
logger.debug("{} #result={}", sql, set);
}
return set;
} else if (isForArray) {
Object array = jdbcTemplate.queryForArray(getDataSource(), sql, args, rowMapper);
if (logger.isDebugEnabled()) {
logger.debug("{} #result={}", sql, array);
}
return array;
} else {
Object r = jdbcTemplate.queryForObject(getDataSource(), sql, args, rowMapper);
if (logger.isDebugEnabled()) {
logger.debug("{} #result={}", sql, r);
}
return r;
}
}
private static <T> RowMapper<T> getRowMapper(Class<T> clazz) {
return JdbcUtils.isSingleColumnClass(clazz) ?
new SingleColumnRowMapper<T>(clazz) :
new BeanPropertyRowMapper<T>(clazz);
}
private class AddableObject<T> {
List<T> hitValueList = null;
Set<T> hitValueSet = null;
Class<T> valueClass;
private AddableObject(int initialCapacity, Class<T> valueClass) {
if (isForSet) {
hitValueSet = new HashSet<T>(initialCapacity * 2);
} else { // 返回List或数组都先使用List
hitValueList = new ArrayList<T>(initialCapacity);
}
this.valueClass = valueClass;
}
public void add(T v) {
if (hitValueList != null) {
hitValueList.add(v);
} else {
hitValueSet.add(v);
}
}
public Object getReturn() {
if (isForList) {
return hitValueList;
} else if (isForSet) {
return hitValueSet;
} else if (isForArray) {
return ArrayUtil.toArray(hitValueList, valueClass);
} else {
throw new UnreachableCodeException();
}
}
@Override
public String toString() {
return hitValueList != null ? hitValueList.toString() : hitValueSet.toString();
}
}
}