/*
* Copyright 2014 mango.concurrent.cc
*
* The Mango 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.RuntimeContext;
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 javax.sql.DataSource;
import java.lang.reflect.Method;
import java.lang.reflect.Type;
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 RowMapper<?> rowMapper;
private boolean isForList;
private boolean isForSet;
private boolean isForArray;
private String interableProperty; // "a in (:1)"中的a
public QueryOperator(ASTRootNode rootNode, Method method, SQLType sqlType) {
super(rootNode, method, sqlType);
init();
}
private void init() {
TypeToken typeToken = new TypeToken(method.getGenericReturnType());
isForList = typeToken.isList();
isForSet = typeToken.isSet();
isForArray = typeToken.isArray();
Class<?> mappedClass = typeToken.getMappedClass();
rowMapper = getRowMapper(mappedClass);
List<ASTIterableParameter> ips = rootNode.getIterableParameters();
if (!ips.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 (ips.size() == 1) {
interableProperty = ips.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");
}
}
}
}
@Override
Type[] getMethodArgTypes(Method method) {
return method.getGenericParameterTypes();
}
@Override
protected void cacheInitPostProcessor() {
if (isUseCache()) {
List<ASTIterableParameter> ips = rootNode.getIterableParameters();
if (ips.size() > 1) {
throw new IncorrectSqlException("if use cache, sql's in clause expected less than or equal 1 but " +
ips.size()); // sql中不能有多个in语句
}
}
}
@Override
public Object execute(Object[] methodArgs) {
RuntimeContext context = buildRuntimeContext(methodArgs);
if (isUseCache()) { // 先使用缓存，再使用db
return isUseMultipleKeys() ?
multipleKeysCache(context, rowMapper.getMappedClass(), getSuffixClass()) :
singleKeyCache(context);
} else { // 直接使用db
return executeFromDb(context);
}
}
private <T, U> Object multipleKeysCache(RuntimeContext context, Class<T> mappedClass, Class<U> suffixClass) {
boolean isDebugEnabled = logger.isDebugEnabled();
Set<String> keys = getCacheKeys(context);
Map<String, Object> cacheResults = getBulkFromCache(keys);
AddableObject<T> addableObj = new AddableObject<T>(keys.size(), mappedClass);
int hitCapacity = cacheResults != null ? cacheResults.size() : 0;
List<U> hitSuffix = new ArrayList<U>(hitCapacity); // 用于debug
Set<U> missSuffix = new HashSet<U>((keys.size() - hitCapacity) * 2);
for (Object suffix : new Iterables(getSuffixObj(context))) {
String key = getCacheKey(suffix);
Object value = cacheResults != null ? cacheResults.get(key) : null;
if (value == null) {
missSuffix.add(suffixClass.cast(suffix));
} else {
addableObj.add(mappedClass.cast(value));
if (isDebugEnabled) {
hitSuffix.add(suffixClass.cast(suffix));
}
}
}
if (isDebugEnabled) {
logger.debug("cache hit #keys={} #values={}", hitSuffix, addableObj);
logger.debug("cache miss #keys={}", missSuffix);
}
if (!missSuffix.isEmpty()) { // 有key没有命中
setSuffixObj(context, missSuffix);
Object dbValues = executeFromDb(context);
for (Object dbValue : new Iterables(dbValues)) {
// db数据添加入结果
addableObj.add(mappedClass.cast(dbValue));
// 添加入缓存
Object suffix = BeanUtil.getPropertyValue(dbValue, interableProperty, mappedClass);
String key = getCacheKey(suffix);
setToCache(key, dbValue);
}
}
return addableObj.getReturn();
}
private Object singleKeyCache(RuntimeContext context) {
String key = getCacheKey(context);
Object value = getFromCache(key);
if (value == null) {
if (logger.isDebugEnabled()) {
logger.debug("cache miss #key＝{}", key);
}
value = executeFromDb(context);
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 Object executeFromDb(RuntimeContext context) {
DataSource ds = getDataSource(context);
String sql = rootNode.getSql(context);
Object[] args = rootNode.getArgs(context);
Object r;
boolean success = false;
long now = System.nanoTime();
try {
if (isForList) {
r = jdbcTemplate.queryForList(ds, sql, args, rowMapper);
} else if (isForSet) {
r = jdbcTemplate.queryForSet(ds, sql, args, rowMapper);
} else if (isForArray) {
r= jdbcTemplate.queryForArray(ds, sql, args, rowMapper);
} else {
r = jdbcTemplate.queryForObject(ds, sql, args, rowMapper);
}
success = true;
} finally {
long cost = System.nanoTime() - now;
if (success) {
statsCounter.recordExecuteSuccess(cost);
} else {
statsCounter.recordExecuteException(cost);
}
}
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();
}
}
}