MyBatis 注解（摘自MyBatis官方文档）

系统管理员 2022-08-26 00:58 8阅读 0赞

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   <th style="padding:8px; vertical-align:bottom; border-top-width:0px">注解</th> 
   <th style="padding:8px; vertical-align:bottom; border-top-width:0px">目标</th> 
   <th style="padding:8px; vertical-align:bottom; border-top-width:0px">相对应的 XML</th> 
   <th style="padding:8px; vertical-align:bottom; border-top-width:0px">描述</th> 
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   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221); background-color:rgb(249,249,249)"> @CacheNamespace</td> 
   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221); background-color:rgb(249,249,249)"> 类</td> 
   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221); background-color:rgb(249,249,249)"> &lt;cache&gt;</td> 
   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221); background-color:rgb(249,249,249)"> <p>为给定的命名空间 (比如类) 配置缓存。</p> <p>&nbsp;属性:implemetation,eviction, flushInterval,size 和 readWrite。</p> </td> 
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   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221)"> @CacheNamespaceRef</td> 
   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221)"> 类</td> 
   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221)"> &lt;cacheRef&gt;</td> 
   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221)"> 参照另外一个命名空间的缓存来使用。 属性:value,应该是一个名空姐的字 符串值(也就是类的完全限定名) 。</td> 
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   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221); background-color:rgb(249,249,249)"> @ConstructorArgs</td> 
   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221); background-color:rgb(249,249,249)"> Method</td> 
   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221); background-color:rgb(249,249,249)"> &lt;constructor&gt;</td> 
   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221); background-color:rgb(249,249,249)"> 收集一组结果传递给一个劫夺对象的 构造方法。属性:value,是形式参数 的数组。</td> 
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   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221)"> @Arg</td> 
   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221)"> 方法</td> 
   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221)"> 
    <ul style="padding:0px; margin:0px 0px 10px 25px"> 
     <li style="color:rgb(64,64,64)">&lt;arg&gt;</li> 
     <li style="color:rgb(64,64,64)">&lt;idArg&gt;</li> 
    </ul> </td> 
   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221)"> 单 独 的 构 造 方 法 参 数 , 是 ConstructorArgs 集合的一部分。属性: id,column,javaType,typeHandler。 id 属性是布尔值, 来标识用于比较的属 性,和&lt;idArg&gt;XML 元素相似。</td> 
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   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221); background-color:rgb(249,249,249)"> @TypeDiscriminator</td> 
   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221); background-color:rgb(249,249,249)"> 方法</td> 
   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221); background-color:rgb(249,249,249)"> &lt;discriminator&gt;</td> 
   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221); background-color:rgb(249,249,249)"> 一组实例值被用来决定结果映射的表 现。 属性: column, javaType, jdbcType, typeHandler,cases。cases 属性就是实 例的数组。</td> 
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   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221)"> @Case</td> 
   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221)"> 方法</td> 
   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221)"> &lt;case&gt;</td> 
   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221)"> 单独实例的值和它对应的映射。属性: value,type,results。Results 属性是结 果数组,因此这个注解和实际的 ResultMap 很相似,由下面的 Results 注解指定。</td> 
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   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221); background-color:rgb(249,249,249)"> @Results</td> 
   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221); background-color:rgb(249,249,249)"> 方法</td> 
   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221); background-color:rgb(249,249,249)"> &lt;resultMap&gt;</td> 
   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221); background-color:rgb(249,249,249)"> 结果映射的列表, 包含了一个特别结果 列如何被映射到属性或字段的详情。 属 性:value,是 Result 注解的数组。</td> 
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   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221)"> @Result</td> 
   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221)"> 方法</td> 
   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221)"> 
    <ul style="padding:0px; margin:0px 0px 10px 25px"> 
     <li style="color:rgb(64,64,64)">&lt;result&gt;</li> 
     <li style="color:rgb(64,64,64)">&lt;id&gt;</li> 
    </ul> </td> 
   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221)"> 在列和属性或字段之间的单独结果映 射。属 性:id,column, property, javaType ,jdbcType ,type Handler, one,many。id 属性是一个布尔值,表 示了应该被用于比较(和在 XML 映射 中的&lt;id&gt;相似)的属性。one 属性是单 独 的 联 系, 和 &lt;association&gt; 相 似 , 而 many 属 性 是 对 集 合 而 言 的 , 和 &lt;collection&gt;相似。 它们这样命名是为了 避免名称冲突。</td> 
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   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221); background-color:rgb(249,249,249)"> @One</td> 
   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221); background-color:rgb(249,249,249)"> 方法</td> 
   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221); background-color:rgb(249,249,249)"> &lt;association&gt;</td> 
   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221); background-color:rgb(249,249,249)"> 复杂类型的单独属性值映射。属性: select,已映射语句(也就是映射器方 法)的完全限定名,它可以加载合适类 型的实例。注意:联合映射在注解 API 中是不支持的。这是因为 Java 注解的 限制,不允许循环引用。</td> 
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   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221)"> @Many</td> 
   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221)"> 方法</td> 
   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221)"> &lt;collection&gt;</td> 
   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221)"> A mapping to a collection property of a complex type. Attributes:&nbsp;select, which is the fully qualified name of a mapped statement (i.e. mapper method) that can load a collection of instances of the appropriate types.&nbsp;<span style="display:inline-block; padding:2px 4px; font-size:11.844px; font-weight:bold; line-height:14px; color:rgb(255,255,255); white-space:nowrap; vertical-align:baseline; background-color:rgb(153,153,153)">NOTE</span>&nbsp;You will notice that join mapping is not supported via the Annotations API. This is due to the limitation in Java Annotations that does not allow for circular references.</td> 
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   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221); background-color:rgb(249,249,249)"> @MapKey</td> 
   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221); background-color:rgb(249,249,249)"> 方法</td> 
   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221); background-color:rgb(249,249,249)"> &nbsp;</td> 
   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221); background-color:rgb(249,249,249)"> 复 杂 类 型 的 集合 属 性 映射 。 属 性 : select,是映射语句(也就是映射器方 法)的完全限定名,它可以加载合适类 型的一组实例。注意:联合映射在 Java 注解中是不支持的。这是因为 Java 注 解的限制,不允许循环引用。</td> 
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   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221)"> @Options</td> 
   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221)"> 方法</td> 
   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221)"> 映射语句的属性</td> 
   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221)"> 这个注解提供访问交换和配置选项的 宽广范围, 它们通常在映射语句上作为 属性出现。 而不是将每条语句注解变复 杂,Options 注解提供连贯清晰的方式 来访问它们。属性:useCache=true , flushCache=false , resultSetType=FORWARD_ONLY , statementType=PREPARED , fetchSize=-1 , , timeout=-1 useGeneratedKeys=false , keyProperty=”id”。 理解 Java 注解是很 重要的,因为没有办法来指定“null” 作为值。因此,一旦你使用了 Options 注解,语句就受所有默认值的支配。要 注意什么样的默认值来避免不期望的 行为。</td> 
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   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221); background-color:rgb(249,249,249)"> 
    <ul style="padding:0px; margin:0px 0px 10px 25px"> 
     <li style="color:rgb(64,64,64)">@Insert</li> 
     <li style="color:rgb(64,64,64)">@Update</li> 
     <li style="color:rgb(64,64,64)">@Delete</li> 
     <li style="color:rgb(64,64,64)">@Select</li> 
    </ul> </td> 
   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221); background-color:rgb(249,249,249)"> 方法</td> 
   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221); background-color:rgb(249,249,249)"> 
    <ul style="padding:0px; margin:0px 0px 10px 25px"> 
     <li style="color:rgb(64,64,64)">&lt;insert&gt;</li> 
     <li style="color:rgb(64,64,64)">&lt;update&gt;</li> 
     <li style="color:rgb(64,64,64)">&lt;delete&gt;</li> 
     <li style="color:rgb(64,64,64)">&lt;select&gt;</li> 
    </ul> </td> 
   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221); background-color:rgb(249,249,249)"> 这些注解中的每一个代表了执行的真 实 SQL。 它们每一个都使用字符串数组 (或单独的字符串)。如果传递的是字 符串数组, 它们由每个分隔它们的单独 空间串联起来。这就当用 Java 代码构 建 SQL 时避免了“丢失空间”的问题。 然而,如果你喜欢,也欢迎你串联单独 的字符串。属性:value,这是字符串 数组用来组成单独的 SQL 语句。</td> 
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   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221)"> 
    <ul style="padding:0px; margin:0px 0px 10px 25px"> 
     <li style="color:rgb(64,64,64)">@InsertProvider</li> 
     <li style="color:rgb(64,64,64)">@UpdateProvider</li> 
     <li style="color:rgb(64,64,64)">@DeleteProvider</li> 
     <li style="color:rgb(64,64,64)">@SelectProvider</li> 
    </ul> </td> 
   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221)"> 方法</td> 
   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221)"> 
    <ul style="padding:0px; margin:0px 0px 10px 25px"> 
     <li style="color:rgb(64,64,64)">&lt;insert&gt;</li> 
     <li style="color:rgb(64,64,64)">&lt;update&gt;</li> 
     <li style="color:rgb(64,64,64)">&lt;delete&gt;</li> 
     <li style="color:rgb(64,64,64)">&lt;select&gt;</li> 
    </ul> </td> 
   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221)"> 这些可选的 SQL 注解允许你指定一个 类名和一个方法在执行时来返回运行 允许创建动态 的 SQL。 基于执行的映射语句, MyBatis 会实例化这个类,然后执行由 provider 指定的方法. 这个方法可以选择性的接 受参数对象作为它的唯一参数, 但是必 须只指定该参数或者没有参数。属性: type,method。type 属性是类的完全限 定名。method 是该类中的那个方法名。 注意: 这节之后是对 SelectBuilder 类的 讨论,它可以帮助你以干净,容于阅读 的方式来构建动态 SQL。</td> 
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   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221); background-color:rgb(249,249,249)"> @Param</td> 
   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221); background-color:rgb(249,249,249)"> Parameter</td> 
   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221); background-color:rgb(249,249,249)"> N/A</td> 
   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221); background-color:rgb(249,249,249)"> 如果你的映射器的方法需要多个参数, 这个注解可以被应用于映射器的方法 参数来给每个参数一个名字。否则,多 参数将会以它们的顺序位置来被命名 (不包括任何 RowBounds 参数) 比如。 #{param1} , #{param2} 等 , 这 是 默 认 的 。 使 用 @Param(“person”),参数应该被命名为 #{person}。</td> 
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   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221)"> @SelectKey</td> 
   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221)"> Method</td> 
   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221)"> &lt;selectKey&gt;</td> 
   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221)"> This annotation duplicates the&nbsp;&lt;selectKey&gt;&nbsp;functionality for methods annotated with&nbsp;@Insert&nbsp;or&nbsp;@InsertProvider. It is ignored for other methods. If you specify a&nbsp;@SelectKey&nbsp;annotation, then MyBatis will ignore any generated key properties set via the&nbsp;@Options&nbsp;annotation, or configuration properties. Attributes: statement an array of strings which is the SQL statement to execute,&nbsp;keyProperty&nbsp;which is the property of the parameter object that will be updated with the new value, before which must be either&nbsp;true&nbsp;or&nbsp;false&nbsp;to denote if the SQL statement should be executed before or after the insert,resultType&nbsp;which is the Java type of the&nbsp;keyProperty, and&nbsp;statementType=PREPARED.</td> 
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   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221); background-color:rgb(249,249,249)"> @ResultMap</td> 
   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221); background-color:rgb(249,249,249)"> Method</td> 
   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221); background-color:rgb(249,249,249)"> N/A</td> 
   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221); background-color:rgb(249,249,249)"> This annotation is used to provide the id of a&nbsp;&lt;resultMap&gt;&nbsp;element in an XML mapper to a&nbsp;@Select&nbsp;or&nbsp;@SelectProviderannotation. This allows annotated selects to reuse resultmaps that are defined in XML. This annotation will override any@Results&nbsp;or&nbsp;@ConstructorArgs&nbsp;annotation if both are specified on an annotated select.</td> 
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   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221)"> @ResultType</td> 
   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221)"> Method</td> 
   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221)"> N/A</td> 
   <td style="padding:8px; vertical-align:top; border-top-width:1px; border-top-style:solid; border-top-color:rgb(221,221,221)"> This annotation is used when using a result handler. In that case, the return type is void so MyBatis must have a way to determine the type of object to construct for each row. If there is an XML result map, use the @ResultMap annotation. If the result type is specified in XML on the&nbsp;&lt;select&gt;&nbsp;element, then no other annotation is necessary. In other cases, use this annotation. For example, if a @Select annotated method will use a result handler, the return type must be void and this annotation (or @ResultMap) is required. This annotation is ignored unless the method return type is void.</td> 
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