/*
    *    Copyright 2009-2022 the original author or authors.
    *
    *    Licensed 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.ibatis.session;
  
  import java.util.Arrays;
  import java.util.Collection;
  import java.util.HashMap;
  import java.util.HashSet;
  import java.util.Iterator;
  import java.util.LinkedList;
  import java.util.List;
  import java.util.Map;
  import java.util.Properties;
  import java.util.Set;
  import java.util.function.BiFunction;
  
  import org.apache.ibatis.binding.MapperRegistry;
  import org.apache.ibatis.builder.CacheRefResolver;
  import org.apache.ibatis.builder.IncompleteElementException;
  import org.apache.ibatis.builder.ResultMapResolver;
  import org.apache.ibatis.builder.annotation.MethodResolver;
  import org.apache.ibatis.builder.xml.XMLStatementBuilder;
  import org.apache.ibatis.cache.Cache;
  import org.apache.ibatis.cache.decorators.FifoCache;
  import org.apache.ibatis.cache.decorators.LruCache;
  import org.apache.ibatis.cache.decorators.SoftCache;
  import org.apache.ibatis.cache.decorators.WeakCache;
  import org.apache.ibatis.cache.impl.PerpetualCache;
  import org.apache.ibatis.datasource.jndi.JndiDataSourceFactory;
  import org.apache.ibatis.datasource.pooled.PooledDataSourceFactory;
  import org.apache.ibatis.datasource.unpooled.UnpooledDataSourceFactory;
  import org.apache.ibatis.executor.BatchExecutor;
  import org.apache.ibatis.executor.CachingExecutor;
  import org.apache.ibatis.executor.Executor;
  import org.apache.ibatis.executor.ReuseExecutor;
  import org.apache.ibatis.executor.SimpleExecutor;
  import org.apache.ibatis.executor.keygen.KeyGenerator;
  import org.apache.ibatis.executor.loader.ProxyFactory;
  import org.apache.ibatis.executor.loader.cglib.CglibProxyFactory;
  import org.apache.ibatis.executor.loader.javassist.JavassistProxyFactory;
  import org.apache.ibatis.executor.parameter.ParameterHandler;
  import org.apache.ibatis.executor.resultset.DefaultResultSetHandler;
  import org.apache.ibatis.executor.resultset.ResultSetHandler;
  import org.apache.ibatis.executor.statement.RoutingStatementHandler;
  import org.apache.ibatis.executor.statement.StatementHandler;
  import org.apache.ibatis.io.VFS;
  import org.apache.ibatis.logging.Log;
  import org.apache.ibatis.logging.LogFactory;
  import org.apache.ibatis.logging.commons.JakartaCommonsLoggingImpl;
  import org.apache.ibatis.logging.jdk14.Jdk14LoggingImpl;
  import org.apache.ibatis.logging.log4j.Log4jImpl;
  import org.apache.ibatis.logging.log4j2.Log4j2Impl;
  import org.apache.ibatis.logging.nologging.NoLoggingImpl;
  import org.apache.ibatis.logging.slf4j.Slf4jImpl;
  import org.apache.ibatis.logging.stdout.StdOutImpl;
  import org.apache.ibatis.mapping.BoundSql;
  import org.apache.ibatis.mapping.Environment;
  import org.apache.ibatis.mapping.MappedStatement;
  import org.apache.ibatis.mapping.ParameterMap;
  import org.apache.ibatis.mapping.ResultMap;
  import org.apache.ibatis.mapping.ResultSetType;
  import org.apache.ibatis.mapping.VendorDatabaseIdProvider;
  import org.apache.ibatis.parsing.XNode;
  import org.apache.ibatis.plugin.Interceptor;
  import org.apache.ibatis.plugin.InterceptorChain;
  import org.apache.ibatis.reflection.DefaultReflectorFactory;
  import org.apache.ibatis.reflection.MetaObject;
  import org.apache.ibatis.reflection.ReflectorFactory;
  import org.apache.ibatis.reflection.factory.DefaultObjectFactory;
  import org.apache.ibatis.reflection.factory.ObjectFactory;
  import org.apache.ibatis.reflection.wrapper.DefaultObjectWrapperFactory;
  import org.apache.ibatis.reflection.wrapper.ObjectWrapperFactory;
  import org.apache.ibatis.scripting.LanguageDriver;
  import org.apache.ibatis.scripting.LanguageDriverRegistry;
  import org.apache.ibatis.scripting.defaults.RawLanguageDriver;
  import org.apache.ibatis.scripting.xmltags.XMLLanguageDriver;
  import org.apache.ibatis.transaction.Transaction;
  import org.apache.ibatis.transaction.jdbc.JdbcTransactionFactory;
  import org.apache.ibatis.transaction.managed.ManagedTransactionFactory;
  import org.apache.ibatis.type.JdbcType;
  import org.apache.ibatis.type.TypeAliasRegistry;
  import org.apache.ibatis.type.TypeHandler;
  import org.apache.ibatis.type.TypeHandlerRegistry;
  
  /**
   * @author Clinton Begin
  */
 public class Configuration {
 
   protected Environment environment;
 
   protected boolean safeRowBoundsEnabled;
   protected boolean safeResultHandlerEnabled = true;
   protected boolean mapUnderscoreToCamelCase;
   protected boolean aggressiveLazyLoading;
   protected boolean multipleResultSetsEnabled = true;
   protected boolean useGeneratedKeys;
   protected boolean useColumnLabel = true;
   protected boolean cacheEnabled = true;
   protected boolean callSettersOnNulls;
   protected boolean useActualParamName = true;
   protected boolean returnInstanceForEmptyRow;
   protected boolean shrinkWhitespacesInSql;
   protected boolean nullableOnForEach;
   protected boolean argNameBasedConstructorAutoMapping;
 
   protected String logPrefix;
   protected Class<? extends Log> logImpl;
   protected Class<? extends VFS> vfsImpl;
   protected Class<?> defaultSqlProviderType;
   protected LocalCacheScope localCacheScope = LocalCacheScope.SESSION;
   protected JdbcType jdbcTypeForNull = JdbcType.OTHER;
   protected Set<String> lazyLoadTriggerMethods = new HashSet<>(Arrays.asList("equals", "clone", "hashCode", "toString"));
   protected Integer defaultStatementTimeout;
   protected Integer defaultFetchSize;
   protected ResultSetType defaultResultSetType;
   protected ExecutorType defaultExecutorType = ExecutorType.SIMPLE;
   protected AutoMappingBehavior autoMappingBehavior = AutoMappingBehavior.PARTIAL;
   protected AutoMappingUnknownColumnBehavior autoMappingUnknownColumnBehavior = AutoMappingUnknownColumnBehavior.NONE;
 
   protected Properties variables = new Properties();
   protected ReflectorFactory reflectorFactory = new DefaultReflectorFactory();
   protected ObjectFactory objectFactory = new DefaultObjectFactory();
   protected ObjectWrapperFactory objectWrapperFactory = new DefaultObjectWrapperFactory();
 
   protected boolean lazyLoadingEnabled = false;
   protected ProxyFactory proxyFactory = new JavassistProxyFactory(); // #224 Using internal Javassist instead of OGNL
 
   protected String databaseId;
   /**
    * Configuration factory class.
    * Used to create Configuration for loading deserialized unread properties.
    *
    * @see <a href='https://github.com/mybatis/old-google-code-issues/issues/300'>Issue 300 (google code)</a>
    */
   protected Class<?> configurationFactory;
 
   protected final MapperRegistry mapperRegistry = new MapperRegistry(this);
   protected final InterceptorChain interceptorChain = new InterceptorChain();
   protected final TypeHandlerRegistry typeHandlerRegistry = new TypeHandlerRegistry(this);
   protected final TypeAliasRegistry typeAliasRegistry = new TypeAliasRegistry();
   protected final LanguageDriverRegistry languageRegistry = new LanguageDriverRegistry();
 
   protected final Map<String, MappedStatement> mappedStatements = new StrictMap<MappedStatement>("Mapped Statements collection")
       .conflictMessageProducer((savedValue, targetValue) ->
           ". please check " + savedValue.getResource() + " and " + targetValue.getResource());
   protected final Map<String, Cache> caches = new StrictMap<>("Caches collection");
   protected final Map<String, ResultMap> resultMaps = new StrictMap<>("Result Maps collection");
   protected final Map<String, ParameterMap> parameterMaps = new StrictMap<>("Parameter Maps collection");
   protected final Map<String, KeyGenerator> keyGenerators = new StrictMap<>("Key Generators collection");
 
   protected final Set<String> loadedResources = new HashSet<>();
   protected final Map<String, XNode> sqlFragments = new StrictMap<>("XML fragments parsed from previous mappers");
 
   protected final Collection<XMLStatementBuilder> incompleteStatements = new LinkedList<>();
   protected final Collection<CacheRefResolver> incompleteCacheRefs = new LinkedList<>();
   protected final Collection<ResultMapResolver> incompleteResultMaps = new LinkedList<>();
   protected final Collection<MethodResolver> incompleteMethods = new LinkedList<>();
 
   /*
    * A map holds cache-ref relationship. The key is the namespace that
    * references a cache bound to another namespace and the value is the
    * namespace which the actual cache is bound to.
    */
   protected final Map<String, String> cacheRefMap = new HashMap<>();
 
   public Configuration(Environment environment) {
     this();
     this.environment = environment;
   }
 
   public Configuration() {
     typeAliasRegistry.registerAlias("JDBC", JdbcTransactionFactory.class);
     typeAliasRegistry.registerAlias("MANAGED", ManagedTransactionFactory.class);
 
     typeAliasRegistry.registerAlias("JNDI", JndiDataSourceFactory.class);
     typeAliasRegistry.registerAlias("POOLED", PooledDataSourceFactory.class);
     typeAliasRegistry.registerAlias("UNPOOLED", UnpooledDataSourceFactory.class);
 
     typeAliasRegistry.registerAlias("PERPETUAL", PerpetualCache.class);
     typeAliasRegistry.registerAlias("FIFO", FifoCache.class);
     typeAliasRegistry.registerAlias("LRU", LruCache.class);
     typeAliasRegistry.registerAlias("SOFT", SoftCache.class);
     typeAliasRegistry.registerAlias("WEAK", WeakCache.class);
 
     typeAliasRegistry.registerAlias("DB_VENDOR", VendorDatabaseIdProvider.class);
 
     typeAliasRegistry.registerAlias("XML", XMLLanguageDriver.class);
     typeAliasRegistry.registerAlias("RAW", RawLanguageDriver.class);
 
     typeAliasRegistry.registerAlias("SLF4J", Slf4jImpl.class);
     typeAliasRegistry.registerAlias("COMMONS_LOGGING", JakartaCommonsLoggingImpl.class);
     typeAliasRegistry.registerAlias("LOG4J", Log4jImpl.class);
     typeAliasRegistry.registerAlias("LOG4J2", Log4j2Impl.class);
     typeAliasRegistry.registerAlias("JDK_LOGGING", Jdk14LoggingImpl.class);
     typeAliasRegistry.registerAlias("STDOUT_LOGGING", StdOutImpl.class);
     typeAliasRegistry.registerAlias("NO_LOGGING", NoLoggingImpl.class);
 
     typeAliasRegistry.registerAlias("CGLIB", CglibProxyFactory.class);
     typeAliasRegistry.registerAlias("JAVASSIST", JavassistProxyFactory.class);
 
     languageRegistry.setDefaultDriverClass(XMLLanguageDriver.class);
     languageRegistry.register(RawLanguageDriver.class);
   }
 
   public String getLogPrefix() {
     return logPrefix;
   }
 
   public void setLogPrefix(String logPrefix) {
     this.logPrefix = logPrefix;
   }
 
   public Class<? extends Log> getLogImpl() {
     return logImpl;
   }
 
   public void setLogImpl(Class<? extends Log> logImpl) {
     if (logImpl != null) {
       this.logImpl = logImpl;
       LogFactory.useCustomLogging(this.logImpl);
     }
   }
 
   public Class<? extends VFS> getVfsImpl() {
     return this.vfsImpl;
   }
 
   public void setVfsImpl(Class<? extends VFS> vfsImpl) {
     if (vfsImpl != null) {
       this.vfsImpl = vfsImpl;
       VFS.addImplClass(this.vfsImpl);
     }
   }
 
   /**
    * Gets an applying type when omit a type on sql provider annotation(e.g. {@link org.apache.ibatis.annotations.SelectProvider}).
    *
    * @return the default type for sql provider annotation
    * @since 3.5.6
    */
   public Class<?> getDefaultSqlProviderType() {
     return defaultSqlProviderType;
   }
 
   /**
    * Sets an applying type when omit a type on sql provider annotation(e.g. {@link org.apache.ibatis.annotations.SelectProvider}).
    *
    * @param defaultSqlProviderType
    *          the default type for sql provider annotation
    * @since 3.5.6
    */
   public void setDefaultSqlProviderType(Class<?> defaultSqlProviderType) {
     this.defaultSqlProviderType = defaultSqlProviderType;
   }
 
   public boolean isCallSettersOnNulls() {
     return callSettersOnNulls;
   }
 
   public void setCallSettersOnNulls(boolean callSettersOnNulls) {
     this.callSettersOnNulls = callSettersOnNulls;
   }
 
   public boolean isUseActualParamName() {
     return useActualParamName;
   }
 
   public void setUseActualParamName(boolean useActualParamName) {
     this.useActualParamName = useActualParamName;
   }
 
   public boolean isReturnInstanceForEmptyRow() {
     return returnInstanceForEmptyRow;
   }
 
   public void setReturnInstanceForEmptyRow(boolean returnEmptyInstance) {
     this.returnInstanceForEmptyRow = returnEmptyInstance;
   }
 
   public boolean isShrinkWhitespacesInSql() {
     return shrinkWhitespacesInSql;
   }
 
   public void setShrinkWhitespacesInSql(boolean shrinkWhitespacesInSql) {
     this.shrinkWhitespacesInSql = shrinkWhitespacesInSql;
   }
 
   /**
    * Sets the default value of 'nullable' attribute on 'foreach' tag.
    *
    * @param nullableOnForEach If nullable, set to {@code true}
    * @since 3.5.9
    */
   public void setNullableOnForEach(boolean nullableOnForEach) {
     this.nullableOnForEach = nullableOnForEach;
   }
 
   /**
    * Returns the default value of 'nullable' attribute on 'foreach' tag.
    *
    * <p>Default is {@code false}.
    *
    * @return If nullable, set to {@code true}
    * @since 3.5.9
    */
   public boolean isNullableOnForEach() {
     return nullableOnForEach;
   }
 
   public boolean isArgNameBasedConstructorAutoMapping() {
     return argNameBasedConstructorAutoMapping;
   }
 
   public void setArgNameBasedConstructorAutoMapping(boolean argNameBasedConstructorAutoMapping) {
     this.argNameBasedConstructorAutoMapping = argNameBasedConstructorAutoMapping;
   }
 
   public String getDatabaseId() {
     return databaseId;
   }
 
   public void setDatabaseId(String databaseId) {
     this.databaseId = databaseId;
   }
 
   public Class<?> getConfigurationFactory() {
     return configurationFactory;
   }
 
   public void setConfigurationFactory(Class<?> configurationFactory) {
     this.configurationFactory = configurationFactory;
   }
 
   public boolean isSafeResultHandlerEnabled() {
     return safeResultHandlerEnabled;
   }
 
   public void setSafeResultHandlerEnabled(boolean safeResultHandlerEnabled) {
     this.safeResultHandlerEnabled = safeResultHandlerEnabled;
   }
 
   public boolean isSafeRowBoundsEnabled() {
     return safeRowBoundsEnabled;
   }
 
   public void setSafeRowBoundsEnabled(boolean safeRowBoundsEnabled) {
     this.safeRowBoundsEnabled = safeRowBoundsEnabled;
   }
 
   public boolean isMapUnderscoreToCamelCase() {
     return mapUnderscoreToCamelCase;
   }
 
   public void setMapUnderscoreToCamelCase(boolean mapUnderscoreToCamelCase) {
     this.mapUnderscoreToCamelCase = mapUnderscoreToCamelCase;
   }
 
   public void addLoadedResource(String resource) {
     loadedResources.add(resource);
   }
 
   public boolean isResourceLoaded(String resource) {
     return loadedResources.contains(resource);
   }
 
   public Environment getEnvironment() {
     return environment;
   }
 
   public void setEnvironment(Environment environment) {
     this.environment = environment;
   }
 
   public AutoMappingBehavior getAutoMappingBehavior() {
     return autoMappingBehavior;
   }
 
   public void setAutoMappingBehavior(AutoMappingBehavior autoMappingBehavior) {
     this.autoMappingBehavior = autoMappingBehavior;
   }
 
   /**
    * Gets the auto mapping unknown column behavior.
    *
    * @return the auto mapping unknown column behavior
    * @since 3.4.0
    */
   public AutoMappingUnknownColumnBehavior getAutoMappingUnknownColumnBehavior() {
     return autoMappingUnknownColumnBehavior;
   }
 
   /**
    * Sets the auto mapping unknown column behavior.
    *
    * @param autoMappingUnknownColumnBehavior
    *          the new auto mapping unknown column behavior
    * @since 3.4.0
    */
   public void setAutoMappingUnknownColumnBehavior(AutoMappingUnknownColumnBehavior autoMappingUnknownColumnBehavior) {
     this.autoMappingUnknownColumnBehavior = autoMappingUnknownColumnBehavior;
   }
 
   public boolean isLazyLoadingEnabled() {
     return lazyLoadingEnabled;
   }
 
   public void setLazyLoadingEnabled(boolean lazyLoadingEnabled) {
     this.lazyLoadingEnabled = lazyLoadingEnabled;
   }
 
   public ProxyFactory getProxyFactory() {
     return proxyFactory;
   }
 
   public void setProxyFactory(ProxyFactory proxyFactory) {
     if (proxyFactory == null) {
       proxyFactory = new JavassistProxyFactory();
     }
     this.proxyFactory = proxyFactory;
   }
 
   public boolean isAggressiveLazyLoading() {
     return aggressiveLazyLoading;
   }
 
   public void setAggressiveLazyLoading(boolean aggressiveLazyLoading) {
     this.aggressiveLazyLoading = aggressiveLazyLoading;
   }
 
   public boolean isMultipleResultSetsEnabled() {
     return multipleResultSetsEnabled;
   }
 
   public void setMultipleResultSetsEnabled(boolean multipleResultSetsEnabled) {
     this.multipleResultSetsEnabled = multipleResultSetsEnabled;
   }
 
   public Set<String> getLazyLoadTriggerMethods() {
     return lazyLoadTriggerMethods;
   }
 
   public void setLazyLoadTriggerMethods(Set<String> lazyLoadTriggerMethods) {
     this.lazyLoadTriggerMethods = lazyLoadTriggerMethods;
   }
 
   public boolean isUseGeneratedKeys() {
     return useGeneratedKeys;
   }
 
   public void setUseGeneratedKeys(boolean useGeneratedKeys) {
     this.useGeneratedKeys = useGeneratedKeys;
   }
 
   public ExecutorType getDefaultExecutorType() {
     return defaultExecutorType;
   }
 
   public void setDefaultExecutorType(ExecutorType defaultExecutorType) {
     this.defaultExecutorType = defaultExecutorType;
   }
 
   public boolean isCacheEnabled() {
     return cacheEnabled;
   }
 
   public void setCacheEnabled(boolean cacheEnabled) {
     this.cacheEnabled = cacheEnabled;
   }
 
   public Integer getDefaultStatementTimeout() {
     return defaultStatementTimeout;
   }
 
   public void setDefaultStatementTimeout(Integer defaultStatementTimeout) {
     this.defaultStatementTimeout = defaultStatementTimeout;
   }
 
   /**
    * Gets the default fetch size.
    *
    * @return the default fetch size
    * @since 3.3.0
    */
   public Integer getDefaultFetchSize() {
     return defaultFetchSize;
   }
 
   /**
    * Sets the default fetch size.
    *
    * @param defaultFetchSize
    *          the new default fetch size
    * @since 3.3.0
    */
   public void setDefaultFetchSize(Integer defaultFetchSize) {
     this.defaultFetchSize = defaultFetchSize;
   }
 
   /**
    * Gets the default result set type.
    *
    * @return the default result set type
    * @since 3.5.2
    */
   public ResultSetType getDefaultResultSetType() {
     return defaultResultSetType;
   }
 
   /**
    * Sets the default result set type.
    *
    * @param defaultResultSetType
    *          the new default result set type
    * @since 3.5.2
    */
   public void setDefaultResultSetType(ResultSetType defaultResultSetType) {
     this.defaultResultSetType = defaultResultSetType;
   }
 
   public boolean isUseColumnLabel() {
     return useColumnLabel;
   }
 
   public void setUseColumnLabel(boolean useColumnLabel) {
     this.useColumnLabel = useColumnLabel;
   }
 
   public LocalCacheScope getLocalCacheScope() {
     return localCacheScope;
   }
 
   public void setLocalCacheScope(LocalCacheScope localCacheScope) {
     this.localCacheScope = localCacheScope;
   }
 
   public JdbcType getJdbcTypeForNull() {
     return jdbcTypeForNull;
   }
 
   public void setJdbcTypeForNull(JdbcType jdbcTypeForNull) {
     this.jdbcTypeForNull = jdbcTypeForNull;
   }
 
   public Properties getVariables() {
     return variables;
   }
 
   public void setVariables(Properties variables) {
     this.variables = variables;
   }
 
   public TypeHandlerRegistry getTypeHandlerRegistry() {
     return typeHandlerRegistry;
   }
 
   /**
    * Set a default {@link TypeHandler} class for {@link Enum}.
    * A default {@link TypeHandler} is {@link org.apache.ibatis.type.EnumTypeHandler}.
    * @param typeHandler a type handler class for {@link Enum}
    * @since 3.4.5
    */
   public void setDefaultEnumTypeHandler(Class<? extends TypeHandler> typeHandler) {
     if (typeHandler != null) {
       getTypeHandlerRegistry().setDefaultEnumTypeHandler(typeHandler);
     }
   }
 
   public TypeAliasRegistry getTypeAliasRegistry() {
     return typeAliasRegistry;
   }
 
   /**
    * Gets the mapper registry.
    *
    * @return the mapper registry
    * @since 3.2.2
    */
   public MapperRegistry getMapperRegistry() {
     return mapperRegistry;
   }
 
   public ReflectorFactory getReflectorFactory() {
     return reflectorFactory;
   }
 
   public void setReflectorFactory(ReflectorFactory reflectorFactory) {
     this.reflectorFactory = reflectorFactory;
   }
 
   public ObjectFactory getObjectFactory() {
     return objectFactory;
   }
 
   public void setObjectFactory(ObjectFactory objectFactory) {
     this.objectFactory = objectFactory;
   }
 
   public ObjectWrapperFactory getObjectWrapperFactory() {
     return objectWrapperFactory;
   }
 
   public void setObjectWrapperFactory(ObjectWrapperFactory objectWrapperFactory) {
     this.objectWrapperFactory = objectWrapperFactory;
   }
 
   /**
    * Gets the interceptors.
    *
    * @return the interceptors
    * @since 3.2.2
    */
   public List<Interceptor> getInterceptors() {
     return interceptorChain.getInterceptors();
   }
 
   public LanguageDriverRegistry getLanguageRegistry() {
     return languageRegistry;
   }
 
   public void setDefaultScriptingLanguage(Class<? extends LanguageDriver> driver) {
     if (driver == null) {
       driver = XMLLanguageDriver.class;
     }
     getLanguageRegistry().setDefaultDriverClass(driver);
   }
 
   public LanguageDriver getDefaultScriptingLanguageInstance() {
     return languageRegistry.getDefaultDriver();
   }
 
   /**
    * Gets the language driver.
    *
    * @param langClass
    *          the lang class
    * @return the language driver
    * @since 3.5.1
    */
   public LanguageDriver getLanguageDriver(Class<? extends LanguageDriver> langClass) {
     if (langClass == null) {
       return languageRegistry.getDefaultDriver();
     }
     languageRegistry.register(langClass);
     return languageRegistry.getDriver(langClass);
   }
 
   /**
    * Gets the default scripting language instance.
    *
    * @return the default scripting language instance
    * @deprecated Use {@link #getDefaultScriptingLanguageInstance()}
    */
   @Deprecated
   public LanguageDriver getDefaultScriptingLanuageInstance() {
     return getDefaultScriptingLanguageInstance();
   }
 
   public MetaObject newMetaObject(Object object) {
     return MetaObject.forObject(object, objectFactory, objectWrapperFactory, reflectorFactory);
   }
 
   public ParameterHandler newParameterHandler(MappedStatement mappedStatement, Object parameterObject, BoundSql boundSql) {
     ParameterHandler parameterHandler = mappedStatement.getLang().createParameterHandler(mappedStatement, parameterObject, boundSql);
     parameterHandler = (ParameterHandler) interceptorChain.pluginAll(parameterHandler);
     return parameterHandler;
   }
 
   public ResultSetHandler newResultSetHandler(Executor executor, MappedStatement mappedStatement, RowBounds rowBounds, ParameterHandler parameterHandler,
       ResultHandler resultHandler, BoundSql boundSql) {
     ResultSetHandler resultSetHandler = new DefaultResultSetHandler(executor, mappedStatement, parameterHandler, resultHandler, boundSql, rowBounds);
     resultSetHandler = (ResultSetHandler) interceptorChain.pluginAll(resultSetHandler);
     return resultSetHandler;
   }
 
   public StatementHandler newStatementHandler(Executor executor, MappedStatement mappedStatement, Object parameterObject, RowBounds rowBounds, ResultHandler resultHandler, BoundSql boundSql) {
     StatementHandler statementHandler = new RoutingStatementHandler(executor, mappedStatement, parameterObject, rowBounds, resultHandler, boundSql);
     statementHandler = (StatementHandler) interceptorChain.pluginAll(statementHandler);
     return statementHandler;
   }
 
   public Executor newExecutor(Transaction transaction) {
     return newExecutor(transaction, defaultExecutorType);
   }
 
   public Executor newExecutor(Transaction transaction, ExecutorType executorType) {
     executorType = executorType == null ? defaultExecutorType : executorType;
     executorType = executorType == null ? ExecutorType.SIMPLE : executorType;
     Executor executor;
     if (ExecutorType.BATCH == executorType) {
       executor = new BatchExecutor(this, transaction);
     } else if (ExecutorType.REUSE == executorType) {
       executor = new ReuseExecutor(this, transaction);
     } else {
       executor = new SimpleExecutor(this, transaction);
     }
     if (cacheEnabled) {
       executor = new CachingExecutor(executor);
     }
     executor = (Executor) interceptorChain.pluginAll(executor);
     return executor;
   }
 
   public void addKeyGenerator(String id, KeyGenerator keyGenerator) {
     keyGenerators.put(id, keyGenerator);
   }
 
   public Collection<String> getKeyGeneratorNames() {
     return keyGenerators.keySet();
   }
 
   public Collection<KeyGenerator> getKeyGenerators() {
     return keyGenerators.values();
   }
 
   public KeyGenerator getKeyGenerator(String id) {
     return keyGenerators.get(id);
   }
 
   public boolean hasKeyGenerator(String id) {
     return keyGenerators.containsKey(id);
   }
 
   public void addCache(Cache cache) {
     caches.put(cache.getId(), cache);
   }
 
   public Collection<String> getCacheNames() {
     return caches.keySet();
   }
 
   public Collection<Cache> getCaches() {
     return caches.values();
   }
 
   public Cache getCache(String id) {
     return caches.get(id);
   }
 
   public boolean hasCache(String id) {
     return caches.containsKey(id);
   }
 
   public void addResultMap(ResultMap rm) {
     resultMaps.put(rm.getId(), rm);
     checkLocallyForDiscriminatedNestedResultMaps(rm);
     checkGloballyForDiscriminatedNestedResultMaps(rm);
   }
 
   public Collection<String> getResultMapNames() {
     return resultMaps.keySet();
   }
 
   public Collection<ResultMap> getResultMaps() {
     return resultMaps.values();
   }
 
   public ResultMap getResultMap(String id) {
     return resultMaps.get(id);
   }
 
   public boolean hasResultMap(String id) {
     return resultMaps.containsKey(id);
   }
 
   public void addParameterMap(ParameterMap pm) {
     parameterMaps.put(pm.getId(), pm);
   }
 
   public Collection<String> getParameterMapNames() {
     return parameterMaps.keySet();
   }
 
   public Collection<ParameterMap> getParameterMaps() {
     return parameterMaps.values();
   }
 
   public ParameterMap getParameterMap(String id) {
     return parameterMaps.get(id);
   }
 
   public boolean hasParameterMap(String id) {
     return parameterMaps.containsKey(id);
   }
 
   public void addMappedStatement(MappedStatement ms) {
     mappedStatements.put(ms.getId(), ms);
   }
 
   public Collection<String> getMappedStatementNames() {
     buildAllStatements();
     return mappedStatements.keySet();
   }
 
   public Collection<MappedStatement> getMappedStatements() {
     buildAllStatements();
     return mappedStatements.values();
   }
 
   public Collection<XMLStatementBuilder> getIncompleteStatements() {
     return incompleteStatements;
   }
 
   public void addIncompleteStatement(XMLStatementBuilder incompleteStatement) {
     incompleteStatements.add(incompleteStatement);
   }
 
   public Collection<CacheRefResolver> getIncompleteCacheRefs() {
     return incompleteCacheRefs;
   }
 
   public void addIncompleteCacheRef(CacheRefResolver incompleteCacheRef) {
     incompleteCacheRefs.add(incompleteCacheRef);
   }
 
   public Collection<ResultMapResolver> getIncompleteResultMaps() {
     return incompleteResultMaps;
   }
 
   public void addIncompleteResultMap(ResultMapResolver resultMapResolver) {
     incompleteResultMaps.add(resultMapResolver);
   }
 
   public void addIncompleteMethod(MethodResolver builder) {
     incompleteMethods.add(builder);
   }
 
   public Collection<MethodResolver> getIncompleteMethods() {
     return incompleteMethods;
   }
 
   public MappedStatement getMappedStatement(String id) {
     return this.getMappedStatement(id, true);
   }
 
   public MappedStatement getMappedStatement(String id, boolean validateIncompleteStatements) {
     if (validateIncompleteStatements) {
       buildAllStatements();
     }
     return mappedStatements.get(id);
   }
 
   public Map<String, XNode> getSqlFragments() {
     return sqlFragments;
   }
 
   public void addInterceptor(Interceptor interceptor) {
     interceptorChain.addInterceptor(interceptor);
   }
 
   public void addMappers(String packageName, Class<?> superType) {
     mapperRegistry.addMappers(packageName, superType);
   }
 
   public void addMappers(String packageName) {
     mapperRegistry.addMappers(packageName);
   }
 
   public <T> void addMapper(Class<T> type) {
     mapperRegistry.addMapper(type);
   }
 
   public <T> T getMapper(Class<T> type, SqlSession sqlSession) {
     return mapperRegistry.getMapper(type, sqlSession);
   }
 
   public boolean hasMapper(Class<?> type) {
     return mapperRegistry.hasMapper(type);
   }
 
   public boolean hasStatement(String statementName) {
     return hasStatement(statementName, true);
   }
 
   public boolean hasStatement(String statementName, boolean validateIncompleteStatements) {
     if (validateIncompleteStatements) {
       buildAllStatements();
     }
     return mappedStatements.containsKey(statementName);
   }
 
   public void addCacheRef(String namespace, String referencedNamespace) {
     cacheRefMap.put(namespace, referencedNamespace);
   }
 
   /*
    * Parses all the unprocessed statement nodes in the cache. It is recommended
    * to call this method once all the mappers are added as it provides fail-fast
    * statement validation.
    */
   protected void buildAllStatements() {
     parsePendingResultMaps();
     if (!incompleteCacheRefs.isEmpty()) {
       synchronized (incompleteCacheRefs) {
         incompleteCacheRefs.removeIf(x -> x.resolveCacheRef() != null);
       }
     }
     if (!incompleteStatements.isEmpty()) {
       synchronized (incompleteStatements) {
         incompleteStatements.removeIf(x -> {
           x.parseStatementNode();
           return true;
         });
       }
     }
     if (!incompleteMethods.isEmpty()) {
       synchronized (incompleteMethods) {
         incompleteMethods.removeIf(x -> {
           x.resolve();
           return true;
         });
       }
     }
   }
 
   private void parsePendingResultMaps() {
     if (incompleteResultMaps.isEmpty()) {
       return;
     }
     synchronized (incompleteResultMaps) {
       boolean resolved;
       IncompleteElementException ex = null;
       do {
         resolved = false;
         Iterator<ResultMapResolver> iterator = incompleteResultMaps.iterator();
         while (iterator.hasNext()) {
           try {
             iterator.next().resolve();
             iterator.remove();
             resolved = true;
           } catch (IncompleteElementException e) {
             ex = e;
           }
         }
       } while (resolved);
       if (!incompleteResultMaps.isEmpty() && ex != null) {
         // At least one result map is unresolvable.
         throw ex;
       }
     }
   }
 
   /**
    * Extracts namespace from fully qualified statement id.
    *
    * @param statementId
    *          the statement id
    * @return namespace or null when id does not contain period.
    */
   protected String extractNamespace(String statementId) {
     int lastPeriod = statementId.lastIndexOf('.');
     return lastPeriod > 0 ? statementId.substring(0, lastPeriod) : null;
   }
 
   // Slow but a one time cost. A better solution is welcome.
   protected void checkGloballyForDiscriminatedNestedResultMaps(ResultMap rm) {
     if (rm.hasNestedResultMaps()) {
       for (Map.Entry<String, ResultMap> entry : resultMaps.entrySet()) {
         Object value = entry.getValue();
         if (value instanceof ResultMap) {
           ResultMap entryResultMap = (ResultMap) value;
           if (!entryResultMap.hasNestedResultMaps() && entryResultMap.getDiscriminator() != null) {
             Collection<String> discriminatedResultMapNames = entryResultMap.getDiscriminator().getDiscriminatorMap().values();
             if (discriminatedResultMapNames.contains(rm.getId())) {
               entryResultMap.forceNestedResultMaps();
             }
           }
         }
       }
     }
   }
 
   // Slow but a one time cost. A better solution is welcome.
   protected void checkLocallyForDiscriminatedNestedResultMaps(ResultMap rm) {
     if (!rm.hasNestedResultMaps() && rm.getDiscriminator() != null) {
       for (Map.Entry<String, String> entry : rm.getDiscriminator().getDiscriminatorMap().entrySet()) {
         String discriminatedResultMapName = entry.getValue();
         if (hasResultMap(discriminatedResultMapName)) {
           ResultMap discriminatedResultMap = resultMaps.get(discriminatedResultMapName);
           if (discriminatedResultMap.hasNestedResultMaps()) {
             rm.forceNestedResultMaps();
             break;
           }
         }
       }
     }
   }
 
   protected static class StrictMap<V> extends HashMap<String, V> {
 
     private static final long serialVersionUID = -4950446264854982944L;
     private final String name;
     private BiFunction<V, V, String> conflictMessageProducer;
 
     public StrictMap(String name, int initialCapacity, float loadFactor) {
       super(initialCapacity, loadFactor);
       this.name = name;
     }
 
     public StrictMap(String name, int initialCapacity) {
       super(initialCapacity);
       this.name = name;
     }
 
     public StrictMap(String name) {
       super();
       this.name = name;
     }
 
     public StrictMap(String name, Map<String, ? extends V> m) {
       super(m);
       this.name = name;
     }
 
     /**
      * Assign a function for producing a conflict error message when contains value with the same key.
      * <p>
      * function arguments are 1st is saved value and 2nd is target value.
      * @param conflictMessageProducer A function for producing a conflict error message
      * @return a conflict error message
      * @since 3.5.0
      */
     public StrictMap<V> conflictMessageProducer(BiFunction<V, V, String> conflictMessageProducer) {
       this.conflictMessageProducer = conflictMessageProducer;
       return this;
     }
 
     @Override
     @SuppressWarnings("unchecked")
     public V put(String key, V value) {
       if (containsKey(key)) {
         throw new IllegalArgumentException(name + " already contains value for " + key
             + (conflictMessageProducer == null ? "" : conflictMessageProducer.apply(super.get(key), value)));
       }
       if (key.contains(".")) {
         final String shortKey = getShortName(key);
         if (super.get(shortKey) == null) {
           super.put(shortKey, value);
         } else {
           super.put(shortKey, (V) new Ambiguity(shortKey));
         }
       }
       return super.put(key, value);
     }
 
     @Override
     public V get(Object key) {
       V value = super.get(key);
       if (value == null) {
         throw new IllegalArgumentException(name + " does not contain value for " + key);
       }
       if (value instanceof Ambiguity) {
         throw new IllegalArgumentException(((Ambiguity) value).getSubject() + " is ambiguous in " + name
             + " (try using the full name including the namespace, or rename one of the entries)");
       }
       return value;
     }
 
     protected static class Ambiguity {
       private final String subject;
 
       public Ambiguity(String subject) {
         this.subject = subject;
       }
 
       public String getSubject() {
         return subject;
       }
     }
 
     private String getShortName(String key) {
       final String[] keyParts = key.split("\\.");
       return keyParts[keyParts.length - 1];
     }
   }
 
 }