diff --git a/docs/spring/cs4b17d13c-a90f-11ee-b0cd-acde48001122.java b/docs/spring/cs4b17d13c-a90f-11ee-b0cd-acde48001122.java
new file mode 100644
index 00000000..6e582685
--- /dev/null
+++ b/docs/spring/cs4b17d13c-a90f-11ee-b0cd-acde48001122.java
@@ -0,0 +1,9 @@
+package dolores.oauthserver.config;
+
+import org.springframework.boot.context.properties.EnableConfigurationProperties;
+import org.springframework.context.annotation.Configuration;
+
+@Configuration
+@EnableConfigurationProperties(OAuth2Properties.class)
+public class OAuth2CoreConfig {
+}
diff --git a/docs/spring/cs4b508e0a-a90f-11ee-b0cd-acde48001122.java b/docs/spring/cs4b508e0a-a90f-11ee-b0cd-acde48001122.java
new file mode 100644
index 00000000..1059332b
--- /dev/null
+++ b/docs/spring/cs4b508e0a-a90f-11ee-b0cd-acde48001122.java
@@ -0,0 +1,40 @@
+/**
+ * Copyright 2009-2018 the original author or authors.
+ * <p>
+ * 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
+ * <p>
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * <p>
+ * 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.sql.Connection;
+
+/**
+ * 事物级别, 封装 java.sql 的事物美剧
+ * @author Clinton Begin
+ */
+public enum TransactionIsolationLevel {
+    NONE(Connection.TRANSACTION_NONE),
+    READ_COMMITTED(Connection.TRANSACTION_READ_COMMITTED),
+    READ_UNCOMMITTED(Connection.TRANSACTION_READ_UNCOMMITTED),
+    REPEATABLE_READ(Connection.TRANSACTION_REPEATABLE_READ),
+    SERIALIZABLE(Connection.TRANSACTION_SERIALIZABLE);
+
+    private final int level;
+
+    TransactionIsolationLevel(int level) {
+        this.level = level;
+    }
+
+    public int getLevel() {
+        return level;
+    }
+}
diff --git a/docs/spring/cs4b881c6c-a90f-11ee-b0cd-acde48001122.java b/docs/spring/cs4b881c6c-a90f-11ee-b0cd-acde48001122.java
new file mode 100644
index 00000000..8b0c22ce
--- /dev/null
+++ b/docs/spring/cs4b881c6c-a90f-11ee-b0cd-acde48001122.java
@@ -0,0 +1,74 @@
+/**
+ * Copyright 2009-2018 the original author or authors.
+ * <p>
+ * 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
+ * <p>
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * <p>
+ * 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.jdbc;
+
+import org.apache.ibatis.type.*;
+
+/**
+ * 对于 null 不同类型的描述, {类型处理器,jdbc类型}
+ * @author Clinton Begin
+ * @author Adam Gent
+ */
+public enum Null {
+    BOOLEAN(new BooleanTypeHandler(), JdbcType.BOOLEAN),
+
+    BYTE(new ByteTypeHandler(), JdbcType.TINYINT),
+    SHORT(new ShortTypeHandler(), JdbcType.SMALLINT),
+    INTEGER(new IntegerTypeHandler(), JdbcType.INTEGER),
+    LONG(new LongTypeHandler(), JdbcType.BIGINT),
+    FLOAT(new FloatTypeHandler(), JdbcType.FLOAT),
+    DOUBLE(new DoubleTypeHandler(), JdbcType.DOUBLE),
+    BIGDECIMAL(new BigDecimalTypeHandler(), JdbcType.DECIMAL),
+
+    STRING(new StringTypeHandler(), JdbcType.VARCHAR),
+    CLOB(new ClobTypeHandler(), JdbcType.CLOB),
+    LONGVARCHAR(new ClobTypeHandler(), JdbcType.LONGVARCHAR),
+
+    BYTEARRAY(new ByteArrayTypeHandler(), JdbcType.LONGVARBINARY),
+    BLOB(new BlobTypeHandler(), JdbcType.BLOB),
+    LONGVARBINARY(new BlobTypeHandler(), JdbcType.LONGVARBINARY),
+
+    OBJECT(new ObjectTypeHandler(), JdbcType.OTHER),
+    OTHER(new ObjectTypeHandler(), JdbcType.OTHER),
+    TIMESTAMP(new DateTypeHandler(), JdbcType.TIMESTAMP),
+    DATE(new DateOnlyTypeHandler(), JdbcType.DATE),
+    TIME(new TimeOnlyTypeHandler(), JdbcType.TIME),
+    SQLTIMESTAMP(new SqlTimestampTypeHandler(), JdbcType.TIMESTAMP),
+    SQLDATE(new SqlDateTypeHandler(), JdbcType.DATE),
+    SQLTIME(new SqlTimeTypeHandler(), JdbcType.TIME);
+
+    /**
+     * 类型处理器
+     */
+    private TypeHandler<?> typeHandler;
+    /**
+     * jdbc 类型
+     */
+    private JdbcType jdbcType;
+
+    Null(TypeHandler<?> typeHandler, JdbcType jdbcType) {
+        this.typeHandler = typeHandler;
+        this.jdbcType = jdbcType;
+    }
+
+    public TypeHandler<?> getTypeHandler() {
+        return typeHandler;
+    }
+
+    public JdbcType getJdbcType() {
+        return jdbcType;
+    }
+}
diff --git a/docs/spring/cs4bbe87d4-a90f-11ee-b0cd-acde48001122.java b/docs/spring/cs4bbe87d4-a90f-11ee-b0cd-acde48001122.java
new file mode 100644
index 00000000..96a1f336
--- /dev/null
+++ b/docs/spring/cs4bbe87d4-a90f-11ee-b0cd-acde48001122.java
@@ -0,0 +1,35 @@
+package com.huifer.design.proxy.cglib;
+
+import net.sf.cglib.proxy.Enhancer;
+import net.sf.cglib.proxy.MethodInterceptor;
+import net.sf.cglib.proxy.MethodProxy;
+
+import java.lang.reflect.Method;
+
+/**
+ * <p>Title : CGLIBZhiLian </p>
+ * <p>Description : </p>
+ *
+ * @author huifer
+ * @date 2019-05-17
+ */
+public class CGLIBZhiLian {
+
+    public Object getInstance(Class<?> clazz) throws Exception {
+        Enhancer enhancer = new Enhancer();
+        enhancer.setSuperclass(clazz);
+
+        enhancer.setCallback(new MethodInterceptor() {
+            @Override
+            public Object intercept(Object o, Method method, Object[] args,
+                                    MethodProxy methodProxy) throws Throwable {
+                System.out.println("CGLIB 代理智联");
+                Object o1 = methodProxy.invokeSuper(o, args);
+                return o1;
+            }
+        });
+
+        return enhancer.create();
+
+    }
+}
diff --git a/docs/spring/cs4bf48604-a90f-11ee-b0cd-acde48001122.java b/docs/spring/cs4bf48604-a90f-11ee-b0cd-acde48001122.java
new file mode 100644
index 00000000..72ddd356
--- /dev/null
+++ b/docs/spring/cs4bf48604-a90f-11ee-b0cd-acde48001122.java
@@ -0,0 +1,141 @@
+/**
+ * Copyright 2009-2019 the original author or authors.
+ * <p>
+ * 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
+ * <p>
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * <p>
+ * 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.logging;
+
+import java.lang.reflect.Constructor;
+
+/**
+ * <p>日志工厂，实现内容:</p>
+ * <ol>
+ *     <li>org.slf4j.Logger 日志框架 slf4j</li>
+ *     <li>org.apache.commons.logging.Log 日志框架 apache</li>
+ *     <li>org.apache.logging.log4j.Logger 日志框架 log4j2</li>
+ *     <li>org.apache.log4j.Logger 日志框架 log4j </li>
+ *     <li>java.util.logging.Logger 日志框架,JDK的logger</li>
+ *
+ * </ol>
+ * @author Clinton Begin
+ * @author Eduardo Macarron
+ */
+public final class LogFactory {
+
+    /**
+     * Marker to be used by logging implementations that support markers.
+     */
+    public static final String MARKER = "MYBATIS";
+
+    private static Constructor<? extends Log> logConstructor;
+
+    /**
+     * 日志的实现类的具体选择
+     */
+    static {
+        // slf4j 日志
+        tryImplementation(LogFactory::useSlf4jLogging);
+        // apache 日志
+        tryImplementation(LogFactory::useCommonsLogging);
+        // log4j2 日志
+        tryImplementation(LogFactory::useLog4J2Logging);
+        // log4 日志
+        tryImplementation(LogFactory::useLog4JLogging);
+        // JDK 日志
+        tryImplementation(LogFactory::useJdkLogging);
+        // 空 日志
+        tryImplementation(LogFactory::useNoLogging);
+    }
+
+    /**
+     * 私有化构造方法,这是一个单例
+     */
+    private LogFactory() {
+        // disable construction
+    }
+
+    public static Log getLog(Class<?> aClass) {
+        return getLog(aClass.getName());
+    }
+
+    public static Log getLog(String logger) {
+        try {
+            return logConstructor.newInstance(logger);
+        } catch (Throwable t) {
+            throw new LogException("Error creating logger for logger " + logger + ".  Cause: " + t, t);
+        }
+    }
+
+    public static synchronized void useCustomLogging(Class<? extends Log> clazz) {
+        setImplementation(clazz);
+    }
+
+    public static synchronized void useSlf4jLogging() {
+        setImplementation(org.apache.ibatis.logging.slf4j.Slf4jImpl.class);
+    }
+
+    public static synchronized void useCommonsLogging() {
+        setImplementation(org.apache.ibatis.logging.commons.JakartaCommonsLoggingImpl.class);
+    }
+
+    public static synchronized void useLog4JLogging() {
+        setImplementation(org.apache.ibatis.logging.log4j.Log4jImpl.class);
+    }
+
+    public static synchronized void useLog4J2Logging() {
+        setImplementation(org.apache.ibatis.logging.log4j2.Log4j2Impl.class);
+    }
+
+    public static synchronized void useJdkLogging() {
+        setImplementation(org.apache.ibatis.logging.jdk14.Jdk14LoggingImpl.class);
+    }
+
+    public static synchronized void useStdOutLogging() {
+        setImplementation(org.apache.ibatis.logging.stdout.StdOutImpl.class);
+    }
+
+    public static synchronized void useNoLogging() {
+        setImplementation(org.apache.ibatis.logging.nologging.NoLoggingImpl.class);
+    }
+
+    /**
+     * 选择具体的日志实现
+     */
+    private static void tryImplementation(Runnable runnable) {
+        if (logConstructor == null) {
+            try {
+                // run()? 似乎违背了代码的语义, 看静态方法.静态方法多行同类型的操作我认为是一个多线程
+                runnable.run();
+            } catch (Throwable t) {
+                // ignore
+            }
+        }
+    }
+
+    /**
+     * 选择具体的日志实现
+     */
+    private static void setImplementation(Class<? extends Log> implClass) {
+        try {
+            Constructor<? extends Log> candidate = implClass.getConstructor(String.class);
+            Log log = candidate.newInstance(LogFactory.class.getName());
+            if (log.isDebugEnabled()) {
+                log.debug("Logging initialized using '" + implClass + "' adapter.");
+            }
+            logConstructor = candidate;
+        } catch (Throwable t) {
+            throw new LogException("Error setting Log implementation.  Cause: " + t, t);
+        }
+    }
+
+}
diff --git a/docs/spring/cs4c2a4b40-a90f-11ee-b0cd-acde48001122.java b/docs/spring/cs4c2a4b40-a90f-11ee-b0cd-acde48001122.java
new file mode 100644
index 00000000..d1f2a3f7
--- /dev/null
+++ b/docs/spring/cs4c2a4b40-a90f-11ee-b0cd-acde48001122.java
@@ -0,0 +1,34 @@
+package com.github.huifer.netty.learn.hello;
+
+import io.netty.bootstrap.ServerBootstrap;
+import io.netty.channel.ChannelFuture;
+import io.netty.channel.EventLoopGroup;
+import io.netty.channel.nio.NioEventLoopGroup;
+import io.netty.channel.socket.nio.NioServerSocketChannel;
+
+public class HelloNetty {
+
+    public static void main(String[] args) {
+        EventLoopGroup boosGroup = new NioEventLoopGroup();
+        EventLoopGroup workerGroup = new NioEventLoopGroup();
+
+        try {
+            ServerBootstrap serverBootstrap
+                    = new ServerBootstrap()
+                    .group(boosGroup, workerGroup)
+                    .channel(NioServerSocketChannel.class)
+                    .childHandler(
+                            new HttpServerHandler()
+                    );
+            ChannelFuture sync = serverBootstrap.bind(1010).sync();
+            sync.channel().closeFuture().sync();
+        } catch (InterruptedException e) {
+            e.printStackTrace();
+        } finally {
+            boosGroup.shutdownGracefully();
+            workerGroup.shutdownGracefully();
+        }
+
+    }
+
+}
diff --git a/docs/spring/cs4c5f653c-a90f-11ee-b0cd-acde48001122.java b/docs/spring/cs4c5f653c-a90f-11ee-b0cd-acde48001122.java
new file mode 100644
index 00000000..5f0d68f4
--- /dev/null
+++ b/docs/spring/cs4c5f653c-a90f-11ee-b0cd-acde48001122.java
@@ -0,0 +1,21 @@
+/**
+ * Copyright 2009-2015 the original author or authors.
+ * <p>
+ * 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
+ * <p>
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * <p>
+ * 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.
+ * <p>
+ * Hyper-simple Datasource.
+ */
+/**
+ * Hyper-simple Datasource.
+ */
+package org.apache.ibatis.datasource.unpooled;
diff --git a/docs/spring/cs4c958d4c-a90f-11ee-b0cd-acde48001122.java b/docs/spring/cs4c958d4c-a90f-11ee-b0cd-acde48001122.java
new file mode 100644
index 00000000..707887fa
--- /dev/null
+++ b/docs/spring/cs4c958d4c-a90f-11ee-b0cd-acde48001122.java
@@ -0,0 +1,57 @@
+/**
+ * Copyright 2009-2016 the original author or authors.
+ * <p>
+ * 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
+ * <p>
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * <p>
+ * 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.submitted.ancestor_ref;
+
+import java.util.List;
+
+public class User {
+    private Integer id;
+    private String name;
+    private User friend;
+    private List<User> friends;
+
+    public Integer getId() {
+        return id;
+    }
+
+    public void setId(Integer id) {
+        this.id = id;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public User getFriend() {
+        return friend;
+    }
+
+    public void setFriend(User friend) {
+        this.friend = friend;
+    }
+
+    public List<User> getFriends() {
+        return friends;
+    }
+
+    public void setFriends(List<User> friends) {
+        this.friends = friends;
+    }
+}
diff --git a/docs/spring/cs4ccbfcec-a90f-11ee-b0cd-acde48001122.java b/docs/spring/cs4ccbfcec-a90f-11ee-b0cd-acde48001122.java
new file mode 100644
index 00000000..e623cd74
--- /dev/null
+++ b/docs/spring/cs4ccbfcec-a90f-11ee-b0cd-acde48001122.java
@@ -0,0 +1,21 @@
+/**
+ * Copyright 2009-2015 the original author or authors.
+ * <p>
+ * 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
+ * <p>
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * <p>
+ * 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.
+ * <p>
+ * Base package for Datasources
+ */
+/**
+ * Base package for Datasources
+ */
+package org.apache.ibatis.datasource;
diff --git a/docs/spring/cs4d03e800-a90f-11ee-b0cd-acde48001122.java b/docs/spring/cs4d03e800-a90f-11ee-b0cd-acde48001122.java
new file mode 100644
index 00000000..4943128e
--- /dev/null
+++ b/docs/spring/cs4d03e800-a90f-11ee-b0cd-acde48001122.java
@@ -0,0 +1,78 @@
+/**
+ * Copyright 2009-2019 the original author or authors.
+ * <p>
+ * 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
+ * <p>
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * <p>
+ * 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.cache;
+
+import org.apache.ibatis.cache.decorators.SerializedCache;
+import org.apache.ibatis.cache.decorators.WeakCache;
+import org.apache.ibatis.cache.impl.PerpetualCache;
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+class WeakCacheTest {
+
+    @Test
+    void shouldDemonstrateObjectsBeingCollectedAsNeeded() {
+        final int N = 3000000;
+        WeakCache cache = new WeakCache(new PerpetualCache("default"));
+        for (int i = 0; i < N; i++) {
+            cache.putObject(i, i);
+            if (cache.getSize() < i + 1) {
+                // System.out.println("Cache exceeded with " + (i + 1) + " entries.");
+                break;
+            }
+            if ((i + 1) % 100000 == 0) {
+                // Try performing GC.
+                System.gc();
+            }
+        }
+        assertTrue(cache.getSize() < N);
+    }
+
+    @Test
+    void shouldDemonstrateCopiesAreEqual() {
+        Cache cache = new WeakCache(new PerpetualCache("default"));
+        cache = new SerializedCache(cache);
+        for (int i = 0; i < 1000; i++) {
+            cache.putObject(i, i);
+            Object value = cache.getObject(i);
+            assertTrue(value == null || value.equals(i));
+        }
+    }
+
+    @Test
+    void shouldRemoveItemOnDemand() {
+        WeakCache cache = new WeakCache(new PerpetualCache("default"));
+        cache.putObject(0, 0);
+        assertNotNull(cache.getObject(0));
+        cache.removeObject(0);
+        assertNull(cache.getObject(0));
+    }
+
+    @Test
+    void shouldFlushAllItemsOnDemand() {
+        WeakCache cache = new WeakCache(new PerpetualCache("default"));
+        for (int i = 0; i < 5; i++) {
+            cache.putObject(i, i);
+        }
+        assertNotNull(cache.getObject(0));
+        assertNotNull(cache.getObject(4));
+        cache.clear();
+        assertNull(cache.getObject(0));
+        assertNull(cache.getObject(4));
+    }
+
+}