/**
* when executing a query operation 1. record this statement's id and it's corresponding Cache
* Object into Global Caching Manager; 2. record this statement's id and
*
* @param invocation
* @return
* @throws Throwable
*/
private Object processQuery(Invocation invocation) throws Throwable {
Object result = invocation.proceed();
if (cachingManager.isCacheEnabled()) {
Object[] args = invocation.getArgs();
MappedStatement mappedStatement = (MappedStatement) args[0];
// 如果本条statementId表示的查询语句配置了 flushCache=true，则清空querCacheOnCommit缓存
if (mappedStatement.isFlushCacheRequired()) {
queryCacheOnCommit.clear();
}
// 如果本条statementId表示的查询语句配置了使用缓存，并且二级缓存不为空，则将StatementId
// 和对应的二级缓存对象映射关系添加到全局缓存映射管理器中
if (mappedStatement.isUseCache() && mappedStatement.getCache() != null) {
cachingManager.appendStatementCacheMap(mappedStatement.getId(), mappedStatement.getCache());
}
Object parameter = args[1];
RowBounds rowBounds = (RowBounds) args[2];
Executor executor = (Executor) invocation.getTarget();
BoundSql boundSql = mappedStatement.getBoundSql(parameter);
// 记录本次查询所产生的CacheKey
CacheKey cacheKey = executor.createCacheKey(mappedStatement, parameter, rowBounds, boundSql);
queryCacheOnCommit.putElement(mappedStatement.getId(), cacheKey);
}
return result;
}
private Object getNestedQueryConstructorValue(
ResultSet rs, ResultMapping constructorMapping, String columnPrefix) throws SQLException {
final String nestedQueryId = constructorMapping.getNestedQueryId();
final MappedStatement nestedQuery = configuration.getMappedStatement(nestedQueryId);
final Class<?> nestedQueryParameterType = nestedQuery.getParameterMap().getType();
final Object nestedQueryParameterObject =
prepareParameterForNestedQuery(
rs, constructorMapping, nestedQueryParameterType, columnPrefix);
Object value = null;
if (nestedQueryParameterObject != null) {
final BoundSql nestedBoundSql = nestedQuery.getBoundSql(nestedQueryParameterObject);
final CacheKey key =
executor.createCacheKey(
nestedQuery, nestedQueryParameterObject, RowBounds.DEFAULT, nestedBoundSql);
final Class<?> targetType = constructorMapping.getJavaType();
final ResultLoader resultLoader =
new ResultLoader(
configuration,
executor,
nestedQuery,
nestedQueryParameterObject,
targetType,
key,
nestedBoundSql);
value = resultLoader.loadResult();
}
return value;
}
private Object getNestedQueryMappingValue(
ResultSet rs,
MetaObject metaResultObject,
ResultMapping propertyMapping,
ResultLoaderMap lazyLoader,
String columnPrefix)
throws SQLException {
final String nestedQueryId = propertyMapping.getNestedQueryId();
final String property = propertyMapping.getProperty();
final MappedStatement nestedQuery = configuration.getMappedStatement(nestedQueryId);
final Class<?> nestedQueryParameterType = nestedQuery.getParameterMap().getType();
final Object nestedQueryParameterObject =
prepareParameterForNestedQuery(rs, propertyMapping, nestedQueryParameterType, columnPrefix);
Object value = NO_VALUE;
if (nestedQueryParameterObject != null) {
final BoundSql nestedBoundSql = nestedQuery.getBoundSql(nestedQueryParameterObject);
final CacheKey key =
executor.createCacheKey(
nestedQuery, nestedQueryParameterObject, RowBounds.DEFAULT, nestedBoundSql);
final Class<?> targetType = propertyMapping.getJavaType();
if (executor.isCached(nestedQuery, key)) {
executor.deferLoad(nestedQuery, metaResultObject, property, key, targetType);
} else {
final ResultLoader resultLoader =
new ResultLoader(
configuration,
executor,
nestedQuery,
nestedQueryParameterObject,
targetType,
key,
nestedBoundSql);
if (propertyMapping.isLazy()) {
lazyLoader.addLoader(property, metaResultObject, resultLoader);
} else {
value = resultLoader.loadResult();
}
}
}
return value;
}
/**
* @description TODO
* @createTime 2016-5-31 下午4:53:32
* @fileName CacheInterceptor.java
* @author yaojiamin
* @param boundSql
* @param cacheKey
*/
@SuppressWarnings({})
public <E> List<E> query(Executor executor, CacheHandlerBean cacheHandlerBean) throws Exception {
BoundSql boundSql =
cacheHandlerBean.getMappedStatement().getBoundSql(cacheHandlerBean.getParameterObject());
CacheKey cacheKey =
executor.createCacheKey(
cacheHandlerBean.getMappedStatement(),
cacheHandlerBean.getParameterObject(),
cacheHandlerBean.getRowBounds(),
boundSql);
MetaObject metaPage = forObject(cacheHandlerBean.getParameterObject());
// 当需要分页查询时，将page参数里的当前页和每页数加到cachekey里
if (isNeedPagination(metaPage)) {
executeQuery(
cacheHandlerBean,
createPageBoundSql(cacheHandlerBean, boundSql),
cloneCacheKey(cacheKey),
executor);
Assert.isTrue(metaPage.getValue(Constants.TOTAL) != null, "Fail to count result!!!");
cacheKey.update(metaPage.getValue(Constants.PAGE_NO));
cacheKey.update(metaPage.getValue(Constants.PAGE_SIZE));
}
return executeQuery(cacheHandlerBean, boundSql, cacheKey, executor);
}