MyBatis直接执行SQL的工具SqlMapper
可能有些人也有过类似需求，一般都会选择使用其他的方式如Spring-JDBC等方式解决。
能否通过MyBatis实现这样的功能呢？
为了让通用Mapper更彻底的支持多表操作以及更灵活的操作，在2.2.0版本增加了一个可以直接执行SQL的新类SqlMapper。
通过这篇博客，我们来了解一下SqlMapper。
SqlMapper提供的方法
SqlMapper提供了以下这些公共方法：
-
Map<String,Object> selectOne(String sql) -
Map<String,Object> selectOne(String sql, Object value) -
<T> T selectOne(String sql, Class<T> resultType) -
<T> T selectOne(String sql, Object value, Class<T> resultType) -
List<Map<String,Object>> selectList(String sql) -
List<Map<String,Object>> selectList(String sql, Object value) -
<T> List<T> selectList(String sql, Class<T> resultType) -
<T> List<T> selectList(String sql, Object value, Class<T> resultType) -
int insert(String sql) -
int insert(String sql, Object value) -
int update(String sql) -
int update(String sql, Object value) -
int delete(String sql) -
int delete(String sql, Object value)
一共14个方法，这些方法的命名和参数和SqlSession接口的很像，只是基本上第一个参数都成了sql。
其中Object value为入参，入参形式和SqlSession中的入参一样，带有入参的方法，在使用时sql可以包含#{param}或${param}形式的参数，这些参数需要通过入参来传值。需要的参数过多的时候，参数可以使用Map类型。另外这种情况下的sql还支持下面这种复杂形式：
<code class="language-java hljs has-numbering" style="display: block; padding: 0px; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-top-left-radius: 0px; border-top-right-radius: 0px; border-bottom-right-radius: 0px; border-bottom-left-radius: 0px; word-wrap: normal; background: transparent;">String sql = <span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"<script>select * from sys_user where 1=1"</span> +
<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"<if test=\"usertype != null\">usertype = #{usertype}</if></script>"</span>;</code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; top: 0px; left: 0px; margin: 0px; padding: 6px 0px 40px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style: none; text-align: right; background-color: rgb(238, 238, 238);"><li style="box-sizing: border-box; padding: 0px 5px;">1</li><li style="box-sizing: border-box; padding: 0px 5px;">2</li></ul>
这种情况用的比较少，不多说。
不带有Object value的所有方法，sql中如果有参数需要手动拼接成一个可以直接执行的sql语句。
在selectXXX方法中，使用Class<T> resultType可以指定返回类型，否则就是Map<String,Object>类型。
实例化SqlMapper
SqlMapper构造参数public SqlMapper(SqlSession sqlSession)，需要一个入参SqlSession sqlSession，在一般系统中，可以按照下面的方式获取：
<code class="language-java hljs has-numbering" style="display: block; padding: 0px; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-top-left-radius: 0px; border-top-right-radius: 0px; border-bottom-right-radius: 0px; border-bottom-left-radius: 0px; word-wrap: normal; background: transparent;">SqlSession sqlSession = (...);<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//通过某些方法获取sqlSession</span> <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//创建sqlMapper</span> SqlMapper sqlMapper = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> SqlMapper(sqlSession);</code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; top: 0px; left: 0px; margin: 0px; padding: 6px 0px 40px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style: none; text-align: right; background-color: rgb(238, 238, 238);"><li style="box-sizing: border-box; padding: 0px 5px;">1</li><li style="box-sizing: border-box; padding: 0px 5px;">2</li><li style="box-sizing: border-box; padding: 0px 5px;">3</li></ul>
如果使用的Spring，那么可以按照下面的方式配置<bean>:
<code class="language-xml hljs has-numbering" style="display: block; padding: 0px; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-top-left-radius: 0px; border-top-right-radius: 0px; border-bottom-right-radius: 0px; border-bottom-left-radius: 0px; word-wrap: normal; background: transparent;"><span class="hljs-tag" style="color: rgb(0, 102, 102); box-sizing: border-box;"><<span class="hljs-title" style="box-sizing: border-box; color: rgb(0, 0, 136);">bean</span> <span class="hljs-attribute" style="box-sizing: border-box; color: rgb(102, 0, 102);">id</span>=<span class="hljs-value" style="box-sizing: border-box; color: rgb(0, 136, 0);">"sqlMapper"</span> <span class="hljs-attribute" style="box-sizing: border-box; color: rgb(102, 0, 102);">class</span>=<span class="hljs-value" style="box-sizing: border-box; color: rgb(0, 136, 0);">"com.github.abel533.sql.SqlMapper"</span> <span class="hljs-attribute" style="box-sizing: border-box; color: rgb(102, 0, 102);">scope</span>=<span class="hljs-value" style="box-sizing: border-box; color: rgb(0, 136, 0);">"prototype"</span>></span> <span class="hljs-tag" style="color: rgb(0, 102, 102); box-sizing: border-box;"><<span class="hljs-title" style="box-sizing: border-box; color: rgb(0, 0, 136);">constructor-arg</span> <span class="hljs-attribute" style="box-sizing: border-box; color: rgb(102, 0, 102);">ref</span>=<span class="hljs-value" style="box-sizing: border-box; color: rgb(0, 136, 0);">"sqlSession"</span>/></span> <span class="hljs-tag" style="color: rgb(0, 102, 102); box-sizing: border-box;"></<span class="hljs-title" style="box-sizing: border-box; color: rgb(0, 0, 136);">bean</span>></span></code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; top: 0px; left: 0px; margin: 0px; padding: 6px 0px 40px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style: none; text-align: right; background-color: rgb(238, 238, 238);"><li style="box-sizing: border-box; padding: 0px 5px;">1</li><li style="box-sizing: border-box; padding: 0px 5px;">2</li><li style="box-sizing: border-box; padding: 0px 5px;">3</li></ul>
在Service中使用的时候可以直接使用@Autowired注入。
简单例子
在src/test/java目录的com.github.abel533.sql包中包含这些方法的测试。
下面挑几个看看如何使用。
selectList
<code class="language-java hljs has-numbering" style="display: block; padding: 0px; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-top-left-radius: 0px; border-top-right-radius: 0px; border-bottom-right-radius: 0px; border-bottom-left-radius: 0px; word-wrap: normal; background: transparent;"><span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//查询，返回List<Map></span>
List<Map<String, Object>> list = sqlMapper.selectList(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"select * from country where id < 11"</span>);
<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//查询，返回指定的实体类</span>
List<Country> countryList = sqlMapper.selectList(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"select * from country where id < 11"</span>, Country.class);
<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//查询，带参数</span>
countryList = sqlMapper.selectList(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"select * from country where id < #{id}"</span>, <span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">11</span>, Country.class);
<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//复杂点的查询，这里参数和上面不同的地方，在于传入了一个对象</span>
Country country = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> Country();
country.setId(<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">11</span>);
countryList = sqlMapper.selectList(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"<script>"</span> +
<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"select * from country "</span> +
<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">" <where>"</span> +
<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">" <if test=\"id != null\">"</span> +
<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">" id < #{id}"</span> +
<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">" </if>"</span> +
<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">" </where>"</span> +
<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"</script>"</span>, country, Country.class);</code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; top: 0px; left: 0px; margin: 0px; padding: 6px 0px 40px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style: none; text-align: right; background-color: rgb(238, 238, 238);"><li style="box-sizing: border-box; padding: 0px 5px;">1</li><li style="box-sizing: border-box; padding: 0px 5px;">2</li><li style="box-sizing: border-box; padding: 0px 5px;">3</li><li style="box-sizing: border-box; padding: 0px 5px;">4</li><li style="box-sizing: border-box; padding: 0px 5px;">5</li><li style="box-sizing: border-box; padding: 0px 5px;">6</li><li style="box-sizing: border-box; padding: 0px 5px;">7</li><li style="box-sizing: border-box; padding: 0px 5px;">8</li><li style="box-sizing: border-box; padding: 0px 5px;">9</li><li style="box-sizing: border-box; padding: 0px 5px;">10</li><li style="box-sizing: border-box; padding: 0px 5px;">11</li><li style="box-sizing: border-box; padding: 0px 5px;">12</li><li style="box-sizing: border-box; padding: 0px 5px;">13</li><li style="box-sizing: border-box; padding: 0px 5px;">14</li><li style="box-sizing: border-box; padding: 0px 5px;">15</li><li style="box-sizing: border-box; padding: 0px 5px;">16</li><li style="box-sizing: border-box; padding: 0px 5px;">17</li><li style="box-sizing: border-box; padding: 0px 5px;">18</li><li style="box-sizing: border-box; padding: 0px 5px;">19</li><li style="box-sizing: border-box; padding: 0px 5px;">20</li></ul>
selectOne
<code class="language-java hljs has-numbering" style="display: block; padding: 0px; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-top-left-radius: 0px; border-top-right-radius: 0px; border-bottom-right-radius: 0px; border-bottom-left-radius: 0px; word-wrap: normal; background: transparent;">Map<String, Object> map = sqlMapper.selectOne(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"select * from country where id = 35"</span>);
map = sqlMapper.selectOne(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"select * from country where id = #{id}"</span>, <span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">35</span>);
Country country = sqlMapper.selectOne(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"select * from country where id = 35"</span>, Country.class);
country = sqlMapper.selectOne(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"select * from country where id = #{id}"</span>, <span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">35</span>, Country.class);</code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; top: 0px; left: 0px; margin: 0px; padding: 6px 0px 40px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style: none; text-align: right; background-color: rgb(238, 238, 238);"><li style="box-sizing: border-box; padding: 0px 5px;">1</li><li style="box-sizing: border-box; padding: 0px 5px;">2</li><li style="box-sizing: border-box; padding: 0px 5px;">3</li><li style="box-sizing: border-box; padding: 0px 5px;">4</li><li style="box-sizing: border-box; padding: 0px 5px;">5</li><li style="box-sizing: border-box; padding: 0px 5px;">6</li><li style="box-sizing: border-box; padding: 0px 5px;">7</li></ul>
insert,update,delete
<code class="language-java hljs has-numbering" style="display: block; padding: 0px; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-top-left-radius: 0px; border-top-right-radius: 0px; border-bottom-right-radius: 0px; border-bottom-left-radius: 0px; word-wrap: normal; background: transparent;"><span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//insert</span>
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> result = sqlMapper.insert(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"insert into country values(1921,'天朝','TC')"</span>);
Country tc = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> Country();
tc.setId(<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">1921</span>);
tc.setCountryname(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"天朝"</span>);
tc.setCountrycode(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"TC"</span>);
<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//注意这里的countrycode和countryname故意写反的</span>
result = sqlMapper.insert(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"insert into country values(#{id},#{countrycode},#{countryname})"</span>
, tc);
<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//update</span>
result = sqlMapper.update(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"update country set countryname = '天朝' where id = 35"</span>);
tc = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> Country();
tc.setId(<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">35</span>);
tc.setCountryname(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"天朝"</span>);
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> result = sqlMapper.update(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"update country set countryname = #{countryname}"</span> +
<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">" where id in(select id from country where countryname like 'A%')"</span>, tc);
<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//delete</span>
result = sqlMapper.delete(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"delete from country where id = 35"</span>);
result = sqlMapper.delete(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"delete from country where id = #{id}"</span>, <span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">35</span>);
</code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; top: 0px; left: 0px; margin: 0px; padding: 6px 0px 40px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style: none; text-align: right; background-color: rgb(238, 238, 238);"><li style="box-sizing: border-box; padding: 0px 5px;">1</li><li style="box-sizing: border-box; padding: 0px 5px;">2</li><li style="box-sizing: border-box; padding: 0px 5px;">3</li><li style="box-sizing: border-box; padding: 0px 5px;">4</li><li style="box-sizing: border-box; padding: 0px 5px;">5</li><li style="box-sizing: border-box; padding: 0px 5px;">6</li><li style="box-sizing: border-box; padding: 0px 5px;">7</li><li style="box-sizing: border-box; padding: 0px 5px;">8</li><li style="box-sizing: border-box; padding: 0px 5px;">9</li><li style="box-sizing: border-box; padding: 0px 5px;">10</li><li style="box-sizing: border-box; padding: 0px 5px;">11</li><li style="box-sizing: border-box; padding: 0px 5px;">12</li><li style="box-sizing: border-box; padding: 0px 5px;">13</li><li style="box-sizing: border-box; padding: 0px 5px;">14</li><li style="box-sizing: border-box; padding: 0px 5px;">15</li><li style="box-sizing: border-box; padding: 0px 5px;">16</li><li style="box-sizing: border-box; padding: 0px 5px;">17</li><li style="box-sizing: border-box; padding: 0px 5px;">18</li><li style="box-sizing: border-box; padding: 0px 5px;">19</li><li style="box-sizing: border-box; padding: 0px 5px;">20</li><li style="box-sizing: border-box; padding: 0px 5px;">21</li><li style="box-sizing: border-box; padding: 0px 5px;">22</li><li style="box-sizing: border-box; padding: 0px 5px;">23</li><li style="box-sizing: border-box; padding: 0px 5px;">24</li><li style="box-sizing: border-box; padding: 0px 5px;">25</li><li style="box-sizing: border-box; padding: 0px 5px;">26</li><li style="box-sizing: border-box; padding: 0px 5px;">27</li></ul>
注意
通过上面这些例子应该能对此有个基本的了解，但是如果你使用参数方式，建议阅读下面的文章：
深入了解MyBatis参数
实现原理
2015-03-09：最初想要设计这个功能的时候，感觉会很复杂，想的也复杂，需要很多个类，因此当时没有实现。
2015-03-10：突发奇想，设计了现在的这种方式。并且有种强烈的感觉就是幸好昨天没有尝试去实现，因为昨天晚上思考这个问题的时候是晚上10点多，而今天（10号）是晚上7点开始思考。我很庆幸在一个更清醒的状态下去写这段代码。
下面简单说思路和实现方式。
在写MyBatis分页插件的时候熟悉了MappedStatement类。
在写通用Mapper的时候熟悉了xml转SqlNode结构。
如果我根据SQL动态的创建一个MappedStatement，然后使用MappedStatement的id在sqlSession中执行不就可以了吗？
想到这一点，一切就简单了。
看看下面select查询创建MappedStatement的代码：
<code class="language-java hljs has-numbering" style="display: block; padding: 0px; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-top-left-radius: 0px; border-top-right-radius: 0px; border-bottom-right-radius: 0px; border-bottom-left-radius: 0px; word-wrap: normal; background: transparent;"><span class="hljs-javadoc" style="color: rgb(136, 0, 0); box-sizing: border-box;">/**
* 创建一个查询的MS
*
*<span class="hljs-javadoctag" style="color: rgb(102, 0, 102); box-sizing: border-box;"> @param</span> msId
*<span class="hljs-javadoctag" style="color: rgb(102, 0, 102); box-sizing: border-box;"> @param</span> sqlSource 执行的sqlSource
*<span class="hljs-javadoctag" style="color: rgb(102, 0, 102); box-sizing: border-box;"> @param</span> resultType 返回的结果类型
*/</span>
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">private</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">newSelectMappedStatement</span>(String msId, SqlSource sqlSource, <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">final</span> Class<?> resultType) {
MappedStatement ms = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> MappedStatement.Builder(
configuration, msId, sqlSource, SqlCommandType.SELECT)
.resultMaps(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> ArrayList<ResultMap>() {
{
add(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> ResultMap.Builder(configuration,
<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"defaultResultMap"</span>,
resultType,
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> ArrayList<ResultMapping>(<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>)).build());
}
})
.build();
<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//缓存</span>
configuration.addMappedStatement(ms);
}</code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; top: 0px; left: 0px; margin: 0px; padding: 6px 0px 40px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style: none; text-align: right; background-color: rgb(238, 238, 238);"><li style="box-sizing: border-box; padding: 0px 5px;">1</li><li style="box-sizing: border-box; padding: 0px 5px;">2</li><li style="box-sizing: border-box; padding: 0px 5px;">3</li><li style="box-sizing: border-box; padding: 0px 5px;">4</li><li style="box-sizing: border-box; padding: 0px 5px;">5</li><li style="box-sizing: border-box; padding: 0px 5px;">6</li><li style="box-sizing: border-box; padding: 0px 5px;">7</li><li style="box-sizing: border-box; padding: 0px 5px;">8</li><li style="box-sizing: border-box; padding: 0px 5px;">9</li><li style="box-sizing: border-box; padding: 0px 5px;">10</li><li style="box-sizing: border-box; padding: 0px 5px;">11</li><li style="box-sizing: border-box; padding: 0px 5px;">12</li><li style="box-sizing: border-box; padding: 0px 5px;">13</li><li style="box-sizing: border-box; padding: 0px 5px;">14</li><li style="box-sizing: border-box; padding: 0px 5px;">15</li><li style="box-sizing: border-box; padding: 0px 5px;">16</li><li style="box-sizing: border-box; padding: 0px 5px;">17</li><li style="box-sizing: border-box; padding: 0px 5px;">18</li><li style="box-sizing: border-box; padding: 0px 5px;">19</li><li style="box-sizing: border-box; padding: 0px 5px;">20</li><li style="box-sizing: border-box; padding: 0px 5px;">21</li><li style="box-sizing: border-box; padding: 0px 5px;">22</li></ul>
代码是不是很简单，这段代码的关键是参数sqlSource，下面是创建SqlSource的方法，分为两种。
一种是一个完整的sql，不需要参数的，可以直接执行的：
<code class="language-java hljs has-numbering" style="display: block; padding: 0px; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-top-left-radius: 0px; border-top-right-radius: 0px; border-bottom-right-radius: 0px; border-bottom-left-radius: 0px; word-wrap: normal; background: transparent;">StaticSqlSource sqlSource = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> StaticSqlSource(configuration, sql);</code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; top: 0px; left: 0px; margin: 0px; padding: 6px 0px 40px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style: none; text-align: right; background-color: rgb(238, 238, 238);"><li style="box-sizing: border-box; padding: 0px 5px;">1</li></ul>
其中configuration从sqlSession中获取，sql就是用户传入到sql语句，是不是也很简单？
另一种是支持动态sql的，支持参数的SqlSource：
<code class="language-java hljs has-numbering" style="display: block; padding: 0px; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-top-left-radius: 0px; border-top-right-radius: 0px; border-bottom-right-radius: 0px; border-bottom-left-radius: 0px; word-wrap: normal; background: transparent;">SqlSource sqlSource = languageDriver.createSqlSource(configuration, sql, parameterType);</code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; top: 0px; left: 0px; margin: 0px; padding: 6px 0px 40px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style: none; text-align: right; background-color: rgb(238, 238, 238);"><li style="box-sizing: border-box; padding: 0px 5px;">1</li></ul>
是不是也很简单？这个方法其实可以兼容上面的StaticSqlSource，这里比上面多了一个parameterType，因为这儿是可以传递参数的，另外languageDriver是从configuration中获取的。
是不是很简单？
我一开始也没想到MyBatis直接执行sql实现起来会这么的容易。
insert,delete,update方法的创建更容易，因为他们的返回值都是int，所以处理起来更简单，有兴趣的可以去通用Mapper下的包com.github.abel533.sql中查看SqlMapper的源码。