(window.webpackJsonp=window.webpackJsonp||[]).push([[507],{944:function(e,r,t){"use strict";t.r(r);var a=t(56),n=Object(a.a)({},(function(){var e=this,r=e.$createElement,t=e._self._c||r;return t("ContentSlotsDistributor",{attrs:{"slot-key":e.$parent.slotKey}},[t("h1",{attrs:{id:"xml-支持-处理-xml-有效负载"}},[t("a",{staticClass:"header-anchor",attrs:{href:"#xml-支持-处理-xml-有效负载"}},[e._v("#")]),e._v(" XML 支持-处理 XML 有效负载")]),e._v(" "),t("h2",{attrs:{id:"xml-支持-处理-xml-有效负载-2"}},[t("a",{staticClass:"header-anchor",attrs:{href:"#xml-支持-处理-xml-有效负载-2"}},[e._v("#")]),e._v(" XML 支持-处理 XML 有效负载")]),e._v(" "),t("p",[e._v("Spring Integration 的 XML 支持扩展了 Spring Integration 与以下组件的核心：")]),e._v(" "),t("ul",[t("li",[t("p",[t("a",{attrs:{href:"#xml-transformation"}},[e._v("编组变压器")])])]),e._v(" "),t("li",[t("p",[t("a",{attrs:{href:"#xml-transformation"}},[e._v("解组变压器")])])]),e._v(" "),t("li",[t("p",[t("a",{attrs:{href:"#xml-transformation"}},[e._v("XSLT 变压器")])])]),e._v(" 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xmlns="http://www.example.org/orders">\n\t<orderItem>\n\t\t<isbn>0321200683</isbn>\n\t\t<quantity>2</quantity>\n\t</orderItem>\n\t<orderItem>\n\t\t<isbn>1590596439</isbn>\n\t\t<quantity>1</quantity>\n\t</orderItem>\n</order>\n')])])]),t("p",[e._v("前面的示例看起来与前面的示例完全相同，但声明了一个默认的名称空间。")]),e._v(" "),t("p",[e._v("但是，前面的 XPath 表达式（"),t("code",[e._v("/order/orderItem")]),e._v("）在这种情况下会失败。")]),e._v(" "),t("p",[e._v("为了解决这个问题，你必须通过设置"),t("code",[e._v("ns-prefix")]),e._v("和"),t("code",[e._v("ns-uri")]),e._v("属性或设置"),t("code",[e._v("namespace-map")]),e._v("属性来提供名称空间前缀和名称空间 URI。名称空间 URI 必须与 XML 文档中声明的名称空间匹配。在前面的示例中，这是"),t("code",[e._v("[http://www.example.org/orders](http://www.example.org/orders)")]),e._v("。")]),e._v(" "),t("p",[e._v("但是，你可以任意选择名称空间前缀。实际上，提供一个空字符串实际上是可行的。（但是，不允许使用 NULL）在名称空间前缀由空字符串组成的情况下，你的 XPath 表达式必须使用冒号（“：”）来指示默认的名称空间。如果不使用冒号，则 XPath 表达式不匹配。下面的 XPath 表达式与前面示例中的 XML 文档匹配：")]),e._v(" "),t("div",{staticClass:"language- 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有效负载。")]),e._v(" "),t("h4",{attrs:{id:"将变压器配置为-bean"}},[t("a",{staticClass:"header-anchor",attrs:{href:"#将变压器配置为-bean"}},[e._v("#")]),e._v(" 将变压器配置为 bean")]),e._v(" "),t("p",[e._v("本节将解释以下转换器的工作方式，以及如何将它们配置为 bean:")]),e._v(" "),t("ul",[t("li",[t("p",[t("a",{attrs:{href:"#xml-unmarshalling-transformer"}},[e._v("解组变压器")])])]),e._v(" "),t("li",[t("p",[t("a",{attrs:{href:"#xml-marshalling-transformer"}},[e._v("编组变压器")])])]),e._v(" "),t("li",[t("p",[t("a",{attrs:{href:"#xml-xslt-payload-transformers"}},[e._v("XSLTpayloadTransformer")])])])]),e._v(" "),t("p",[e._v("所有的 XML 转换器都扩展了["),t("code",[e._v("AbstractTransformer")]),e._v("]（https://DOCS. 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Spring.io/ Spring-integration/api/api/integration/xml/result/resultfactory.html）。")])])]),e._v(" "),t("tbody")]),e._v(" "),t("h5",{attrs:{id:"使用xsltpayloadtransformer"}},[t("a",{staticClass:"header-anchor",attrs:{href:"#使用xsltpayloadtransformer"}},[e._v("#")]),e._v(" 使用"),t("code",[e._v("XsltPayloadTransformer")])]),e._v(" "),t("p",[e._v("对"),t("code",[e._v("XsltPayloadTransformer")]),e._v("的命名空间支持允许你传入"),t("code",[e._v("Resource")]),e._v("（以便创建["),t("code",[e._v("Templates")]),e._v("]（https://DOCS.oracle.com/javase/6/DOCS/api/javax/xml/transform/templates.html）实例）或传入预先创建的"),t("code",[e._v("Templates")]),e._v("实例作为参考。与编组转换器一样，你可以通过指定"),t("code",[e._v("result-factory")]),e._v("或"),t("code",[e._v("result-type")]),e._v("属性来控制结果输出的类型。当需要在发送之前转换结果时，可以使用"),t("code",[e._v("result-transformer")]),e._v("属性来引用"),t("code",[e._v("ResultTransformer")]),e._v("的实现。")]),e._v(" "),t("table",[t("thead",[t("tr",[t("th"),e._v(" "),t("th",[e._v("如果指定"),t("code",[e._v("result-factory")]),e._v("或"),t("code",[e._v("result-type")]),e._v("属性，则底层["),t("code",[e._v("alwaysUseResultFactory")]),e._v("]（https://DOCS. 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Spring.api/api/api/api/api/api/api63/apylotframFramework/xtframework/xparser.html）设置")])])]),e._v(" "),t("tbody")]),e._v(" "),t("p",[e._v("下面的示例配置了两个 XSLT 转换器：")]),e._v(" "),t("div",{staticClass:"language- extra-class"},[t("pre",{pre:!0,attrs:{class:"language-text"}},[t("code",[e._v('<int-xml:xslt-transformer id="xsltTransformerWithResource"\n    input-channel="withResourceIn" output-channel="output"\n    xsl-resource="org/springframework/integration/xml/config/test.xsl"/>\n\n<int-xml:xslt-transformer id="xsltTransformerWithTemplatesAndResultTransformer"\n    input-channel="withTemplatesAndResultTransformerIn" output-channel="output"\n    xsl-templates="templates"\n    result-transformer="resultTransformer"/>\n')])])]),t("p",[e._v("你可能需要访问"),t("code",[e._v("Message")]),e._v("数据，例如"),t("code",[e._v("Message")]),e._v("头，以便协助转换。例如，你可能需要访问某些"),t("code",[e._v("Message")]),e._v("头，并将它们作为参数传递给转换器（例如，"),t("code",[e._v("transformer.setParameter(..)")]),e._v("）。 Spring 集成提供了两种方便的方式来实现这一点，如下例所示：")]),e._v(" "),t("div",{staticClass:"language- extra-class"},[t("pre",{pre:!0,attrs:{class:"language-text"}},[t("code",[e._v('<int-xml:xslt-transformer id="paramHeadersCombo"\n    input-channel="paramHeadersComboChannel" output-channel="output"\n    xsl-resource="classpath:transformer.xslt"\n    xslt-param-headers="testP*, *foo, bar, baz">\n\n    <int-xml:xslt-param name="helloParameter" value="hello"/>\n    <int-xml:xslt-param name="firstName" expression="headers.fname"/>\n</int-xml:xslt-transformer>\n')])])]),t("p",[e._v("如果消息头名称与参数名称一一匹配，则可以使用"),t("code",[e._v("xslt-param-headers")]),e._v("属性。在其中，你可以使用通配符进行简单的模式匹配。它支持以下简单的模式样式："),t("code",[e._v("xxx*")]),e._v("，"),t("code",[e._v("**xxx**")]),t("strong",[e._v("，"),t("code",[e._v("*xxx")])]),e._v("，和"),t("code",[e._v("xxx*yyy")]),e._v("。")]),e._v(" "),t("p",[e._v("你还可以通过使用"),t("code",[e._v("<xslt-param/>")]),e._v("元素来配置各个 XSLT 参数。在该元素上，你可以设置"),t("code",[e._v("expression")]),e._v("属性或"),t("code",[e._v("value")]),e._v("属性。"),t("code",[e._v("expression")]),e._v("属性应该是任何有效的 SPEL 表达式，而"),t("code",[e._v("Message")]),e._v("是表达式求值上下文的根对象。"),t("code",[e._v("value")]),e._v("属性（与 Spring bean 中的任何"),t("code",[e._v("value")]),e._v("一样）允许你指定简单的标量值。你也可以使用属性占位符（例如"),t("code",[e._v("${some.value}")]),e._v("）。因此，使用"),t("code",[e._v("expression")]),e._v("和"),t("code",[e._v("value")]),e._v("属性，你可以将 XSLT 参数映射到"),t("code",[e._v("Message")]),e._v("的任何可访问部分以及任何文本值。")]),e._v(" "),t("p",[e._v("从 Spring Integration3.0 开始，你现在可以通过设置"),t("code",[e._v("transformer-factory-class")]),e._v("属性来指定 Transformer Factory 类名称。")]),e._v(" "),t("h4",{attrs:{id:"名称空间配置和结果转换器"}},[t("a",{staticClass:"header-anchor",attrs:{href:"#名称空间配置和结果转换器"}},[e._v("#")]),e._v(" 名称空间配置和结果转换器")]),e._v(" "),t("p",[e._v("我们在[使用"),t("code",[e._v("ResultTransformer")]),e._v("实现]（#xml-using-result-transformers）中介绍了使用结果转换器的情况。本节中的示例使用 XML 名称空间配置来演示几个特殊的用例。首先，我们定义"),t("code",[e._v("ResultTransformer")]),e._v("，如下例所示：")]),e._v(" "),t("div",{staticClass:"language- extra-class"},[t("pre",{pre:!0,attrs:{class:"language-text"}},[t("code",[e._v('<beans:bean id="resultToDoc" class="o.s.i.xml.transformer.ResultToDocumentTransformer"/>\n')])])]),t("p",[e._v("此"),t("code",[e._v("ResultTransformer")]),e._v("接受"),t("code",[e._v("StringResult")]),e._v("或"),t("code",[e._v("DOMResult")]),e._v("作为输入，并将输入转换为"),t("code",[e._v("Document")]),e._v("。")]),e._v(" "),t("p",[e._v("现在我们可以申报变压器了，具体如下：")]),e._v(" "),t("div",{staticClass:"language- extra-class"},[t("pre",{pre:!0,attrs:{class:"language-text"}},[t("code",[e._v('<int-xml:xslt-transformer input-channel="in" output-channel="fahrenheitChannel"\n    xsl-resource="classpath:noop.xslt" result-transformer="resultToDoc"/>\n')])])]),t("p",[e._v("如果传入消息的有效负载类型为"),t("code",[e._v("Source")]),e._v("，那么作为第一步，通过使用"),t("code",[e._v("ResultFactory")]),e._v("来确定"),t("code",[e._v("Result")]),e._v("。由于我们没有指定"),t("code",[e._v("ResultFactory")]),e._v("，所以使用了缺省的"),t("code",[e._v("DomResultFactory")]),e._v("，这意味着转换会产生"),t("code",[e._v("DomResult")]),e._v("。")]),e._v(" "),t("p",[e._v("然而，当我们指定一个"),t("code",[e._v("ResultTransformer")]),e._v("时，它被使用，结果"),t("code",[e._v("Message")]),e._v("的有效负载类型为"),t("code",[e._v("Document")]),e._v("。")]),e._v(" "),t("table",[t("thead",[t("tr",[t("th"),e._v(" "),t("th",[e._v("指定的"),t("code",[e._v("ResultTransformer")]),e._v("将被"),t("code",[e._v("String")]),e._v("或"),t("code",[e._v("Document")]),e._v("有效载荷忽略。"),t("br"),e._v("如果传入消息的有效载荷类型为"),t("code",[e._v("String")]),e._v("，则 XSLT 转换后的有效载荷为"),t("code",[e._v("String")]),e._v("。"),t("br"),e._v("类似地，如果传入消息的有效载荷类型为"),t("code",[e._v("Document")]),e._v("，XSLT 转换后的有效负载是"),t("code",[e._v("Document")]),e._v("。")])])]),e._v(" "),t("tbody")]),e._v(" "),t("p",[e._v("如果消息有效负载不是"),t("code",[e._v("Source")]),e._v("、"),t("code",[e._v("String")]),e._v("或"),t("code",[e._v("Document")]),e._v("，则作为一个后备选项，我们尝试通过使用默认的["),t("code",[e._v("Source")]),e._v("]（https://DOCS. 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"),t("h4",{attrs:{id:"简单的-xpath-转换"}},[t("a",{staticClass:"header-anchor",attrs:{href:"#简单的-xpath-转换"}},[e._v("#")]),e._v(" 简单的 XPath 转换")]),e._v(" "),t("p",[e._v("考虑以下变压器配置：")]),e._v(" "),t("div",{staticClass:"language- extra-class"},[t("pre",{pre:!0,attrs:{class:"language-text"}},[t("code",[e._v('<int-xml:xpath-transformer input-channel="inputChannel" output-channel="outputChannel"\n      xpath-expression="/person/@name" />\n')])])]),t("p",[e._v("还要考虑以下"),t("code",[e._v("Message")]),e._v(":")]),e._v(" "),t("div",{staticClass:"language- extra-class"},[t("pre",{pre:!0,attrs:{class:"language-text"}},[t("code",[e._v("Message<?> message =\n  MessageBuilder.withPayload(\"<person name='John Doe' age='42' married='true'/>\").build();\n")])])]),t("p",[e._v("在将此消息发送到“InputChannel”之后，先前配置的 XPath Transformer 将此 XML 消息转换为一个简单的"),t("code",[e._v("Message")]),e._v("，其有效负载为’John Doe’，所有这些都基于"),t("code",[e._v("xpath-expression")]),e._v("属性中指定的简单 XPath 表达式。")]),e._v(" "),t("p",[e._v("XPath 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           xpath-expression="/person/@married = \'true\'"\n                           evaluation-type="BOOLEAN_RESULT" output-channel="output"/>\n')])])]),t("h4",{attrs:{id:"节点映射器"}},[t("a",{staticClass:"header-anchor",attrs:{href:"#节点映射器"}},[e._v("#")]),e._v(" 节点映射器")]),e._v(" "),t("p",[e._v("如果需要为通过 XPath 表达式提取的节点提供自定义映射，则可以提供对"),t("code",[e._v("org.springframework.xml.xpath.NodeMapper")]),e._v("的实现的引用（由"),t("code",[e._v("XPathOperations")]),e._v("使用的接口实现为在每个节点的基础上映射"),t("code",[e._v("Node")]),e._v("对象）。要提供对"),t("code",[e._v("NodeMapper")]),e._v("的引用，可以使用"),t("code",[e._v("node-mapper")]),e._v("属性，如下例所示：")]),e._v(" "),t("div",{staticClass:"language- extra-class"},[t("pre",{pre:!0,attrs:{class:"language-text"}},[t("code",[e._v('<int-xml:xpath-transformer input-channel="nodeMapperInput" xpath-expression="/person/@age"\n                           node-mapper="testNodeMapper" 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converter="testXmlPayloadConverter" />\n')])])]),t("p",[e._v("下面的示例显示了与前面的示例一起工作的"),t("code",[e._v("XmlPayloadConverter")]),e._v("实现：")]),e._v(" "),t("div",{staticClass:"language- extra-class"},[t("pre",{pre:!0,attrs:{class:"language-text"}},[t("code",[e._v("class TestXmlPayloadConverter implements XmlPayloadConverter {\n  public Source convertToSource(Object object) {\n    throw new UnsupportedOperationException();\n  }\n  //\n  public Node convertToNode(Object object) {\n    try {\n      return DocumentBuilderFactory.newInstance().newDocumentBuilder().parse(\n          new InputSource(new StringReader(\"<test type='custom'/>\")));\n    }\n    catch (Exception e) {\n      throw new IllegalStateException(e);\n    }\n  }\n  //\n  public Document convertToDocument(Object object) {\n    throw new UnsupportedOperationException();\n  }\n}\n")])])]),t("p",[e._v("如果不提供此引用，则使用"),t("code",[e._v("DefaultXmlPayloadConverter")]),e._v("。在大多数情况下，它应该足够了，因为它可以从"),t("code",[e._v("Node")]),e._v("、"),t("code",[e._v("Document")]),e._v("、"),t("code",[e._v("Source")]),e._v("、"),t("code",[e._v("File")]),e._v("、"),t("code",[e._v("String")]),e._v("、"),t("code",[e._v("InputStream")]),e._v("和"),t("code",[e._v("byte[]")]),e._v("有效载荷转换。如果你需要扩展到该默认实现的功能之外，那么上游"),t("code",[e._v("Transformer")]),e._v("可能是一个更好的选择，而不是在这里提供对该策略的自定义实现的引用。")]),e._v(" "),t("h3",{attrs:{id:"分割-xml-消息"}},[t("a",{staticClass:"header-anchor",attrs:{href:"#分割-xml-消息"}},[e._v("#")]),e._v(" 分割 XML 消息")]),e._v(" "),t("p",[t("code",[e._v("XPathMessageSplitter")]),e._v("支持带有"),t("code",[e._v("String")]),e._v("或"),t("code",[e._v("Document")]),e._v("有效负载的消息。拆分器使用提供的 XPath 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<property name="outputChannel" ref="orderItemsChannel" />\n        </bean>\n    </constructor-arg>\n</bean>\n')])])]),t("p",[e._v("XPath Splitter 名称空间支持允许你创建带有输入通道和输出通道的消息端点，如下例所示：")]),e._v(" "),t("div",{staticClass:"language- extra-class"},[t("pre",{pre:!0,attrs:{class:"language-text"}},[t("code",[e._v('\x3c!-- Split the order into items and create a new message for each item node --\x3e\n<int-xml:xpath-splitter id="orderItemSplitter"\n                       input-channel="orderChannel"\n                       output-channel="orderItemsChannel">\n    <int-xml:xpath-expression expression="/order/items"/>\n</int-xml:xpath-splitter>\n\n\x3c!-- Split the order into items, create a new document for each item--\x3e\n<int-xml:xpath-splitter id="orderItemDocumentSplitter"\n                       input-channel="orderChannel"\n                       output-channel="orderItemsChannel"\n                       create-documents="true">\n    <int-xml:xpath-expression expression="/order/items"/>\n    <int:poller fixed-rate="2000"/>\n</int-xml:xpath-splitter>\n')])])]),t("p",[e._v("从版本 4.2 开始，当请求"),t("code",[e._v("payload")]),e._v("类型不是"),t("code",[e._v("org.w3c.dom.Node")]),e._v("时，"),t("code",[e._v("outputProperties")]),e._v("实例的"),t("code",[e._v("OutputKeys.OMIT_XML_DECLARATION")]),e._v("属性（例如"),t("code",[e._v("OutputKeys.OMIT_XML_DECLARATION")]),e._v("）公开。下面的示例定义了一个属性，并将其与"),t("code",[e._v("output-properties")]),e._v("属性一起使用：")]),e._v(" "),t("div",{staticClass:"language- extra-class"},[t("pre",{pre:!0,attrs:{class:"language-text"}},[t("code",[e._v('<util:properties id="outputProperties">\n\t<beans:prop key="#{T (javax.xml.transform.OutputKeys).OMIT_XML_DECLARATION}">yes</beans:prop>\n</util:properties>\n\n<xpath-splitter input-channel="input"\n             output-properties="outputProperties">\n    <xpath-expression expression="/orders/order"/>\n</xpath-splitter>\n')])])]),t("p",[e._v("从"),t("code",[e._v("version 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extra-class"},[t("pre",{pre:!0,attrs:{class:"language-text"}},[t("code",[e._v('<int-xml:xpath-router id="orderTypeRouter" input-channel="orderChannel">\n    <int-xml:xpath-expression expression="/order/type"/>\n</int-xml:xpath-router>\n')])])]),t("table",[t("thead",[t("tr",[t("th"),e._v(" "),t("th",[e._v("有关路由器中常见的属性的概述，请参见"),t("RouterLink",{attrs:{to:"/spring-integration/router.html#router-common-parameters"}},[e._v("通用路由器参数")]),e._v("。")],1)])]),e._v(" "),t("tbody")]),e._v(" "),t("p",[e._v("在内部，XPath 表达式被求值为类型"),t("code",[e._v("NODESET")]),e._v("，并转换为表示通道名的"),t("code",[e._v("List<String>")]),e._v("。通常，这样的列表只包含一个通道名。然而，基于 XPath 表达式的结果，如果 XPath 表达式返回多个值，则 XPath 路由器还可以具有收件人列表路由器的特性。在这种情况下，"),t("code",[e._v("List<String>")]),e._v("包含多个通道名。因此，消息被发送到列表中的所有通道。")]),e._v(" "),t("p",[e._v("因此，假设传递给以下路由器配置的 XML 文件包含许多表示通道名的"),t("code",[e._v("responder")]),e._v("子元素，则消息将被发送到所有这些通道：")]),e._v(" "),t("div",{staticClass:"language- extra-class"},[t("pre",{pre:!0,attrs:{class:"language-text"}},[t("code",[e._v('\x3c!-- route the order to all responders--\x3e\n<int-xml:xpath-router id="responderRouter" input-channel="orderChannel">\n    <int-xml:xpath-expression expression="/request/responders"/>\n</int-xml:xpath-router>\n')])])]),t("p",[e._v("如果返回的值不直接表示通道名称，则可以指定其他映射参数，将这些返回的值映射到实际的通道名称。例如，如果"),t("code",[e._v("/request/responders")]),e._v("表达式导致两个值（"),t("code",[e._v("responderA")]),e._v("和"),t("code",[e._v("responderB")]),e._v("），但不希望将响应者名称与通道名称耦合，则可以提供额外的映射配置，例如：")]),e._v(" "),t("div",{staticClass:"language- extra-class"},[t("pre",{pre:!0,attrs:{class:"language-text"}},[t("code",[e._v('\x3c!-- route the order to all responders--\x3e\n<int-xml:xpath-router id="responderRouter" input-channel="orderChannel">\n    <int-xml:xpath-expression expression="/request/responders"/>\n    <int-xml:mapping value="responderA" channel="channelA"/>\n    <int-xml:mapping value="responderB" channel="channelB"/>\n</int-xml:xpath-router>\n')])])]),t("p",[e._v("如前所述，XPath 表达式的默认求值类型是"),t("code",[e._v("NODESET")]),e._v("，它被转换为通道名的"),t("code",[e._v("List<String>")]),e._v("，它处理单个通道场景以及多个通道场景。")]),e._v(" "),t("p",[e._v("尽管如此，某些 XPath 表达式从一开始就可以计算为类型"),t("code",[e._v("String")]),e._v("。例如，考虑下面的 XPath 表达式：")]),e._v(" "),t("div",{staticClass:"language- extra-class"},[t("pre",{pre:!0,attrs:{class:"language-text"}},[t("code",[e._v("name(./node())\n")])])]),t("p",[e._v("这个表达式返回根节点的名称。如果使用了默认的求值类型"),t("code",[e._v("NODESET")]),e._v("，则会导致异常。")]),e._v(" "),t("p",[e._v("对于这些场景，你可以使用"),t("code",[e._v("evaluate-as-string")]),e._v("属性，该属性允许你管理求值类型。默认情况下是"),t("code",[e._v("FALSE")]),e._v("。但是，如果将其设置为"),t("code",[e._v("TRUE")]),e._v("，则使用"),t("code",[e._v("String")]),e._v("求值类型。")]),e._v(" "),t("table",[t("thead",[t("tr",[t("th"),e._v(" "),t("th",[e._v("XPath1.0 指定了 4 种数据类型："),t("br"),t("br"),e._v("*node-sets"),t("br"),t("br"),e._v("*strings"),t("br"),e._v("*number"),t("br"),t("em",[e._v("boolean当使用可选路径"),t("br"),e._v("时，返回值由"),t("code",[e._v("string()")]),e._v("函数求值，正如 XPath 规范中所定义的。"),t("br"),e._v("这意味着，如果表达式选择了多个节点，它将返回第一个节点的字符串值。"),t("br"),t("br"),e._v("有关更多信息，请参见："),t("br"),t("a",{attrs:{href:"https://www.w3.org/TR/xpath/",target:"_blank",rel:"noopener noreferrer"}},[e._v("规范：XMLPath 语言 1.0 版本"),t("OutboundLink")],1),t("br")]),t("a",{attrs:{href:"https://www.w3.org/TR/xpath-functions-31",target:"_blank",rel:"noopener noreferrer"}},[e._v("XPath 规范-string（）函数"),t("OutboundLink")],1)])])]),e._v(" "),t("tbody")]),e._v(" "),t("p",[e._v("例如，如果我们想基于根节点的名称进行路由，我们可以使用以下配置：")]),e._v(" "),t("div",{staticClass:"language- extra-class"},[t("pre",{pre:!0,attrs:{class:"language-text"}},[t("code",[e._v('<int-xml:xpath-router id="xpathRouterAsString"\n        input-channel="xpathStringChannel"\n        evaluate-as-string="true">\n    <int-xml:xpath-expression expression="name(./node())"/>\n</int-xml:xpath-router>\n')])])]),t("h4",{attrs:{id:"xml-有效负载转换器"}},[t("a",{staticClass:"header-anchor",attrs:{href:"#xml-有效负载转换器"}},[e._v("#")]),e._v(" XML 有效负载转换器")]),e._v(" "),t("p",[e._v("对于 XPath 路由器，你还可以在 XPath 评估之前指定转换有效负载时使用的转换器。因此，XPath 路由器支持"),t("code",[e._v("XmlPayloadConverter")]),e._v("策略的自定义实现，并且当在 XML 中配置"),t("code",[e._v("xpath-router")]),e._v("元素时，可以通过"),t("code",[e._v("converter")]),e._v("属性提供对这种实现的引用。")]),e._v(" "),t("p",[e._v("如果没有显式提供此引用，则使用"),t("code",[e._v("DefaultXmlPayloadConverter")]),e._v("。在大多数情况下，它应该足够了，因为它可以从节点、文档、源、文件和字符串类型的有效负载转换。如果你需要扩展到该默认实现的能力之外，那么在大多数情况下，上游转换器通常是更好的选择，而不是在这里提供对此策略的自定义实现的引用。")]),e._v(" "),t("h3",{attrs:{id:"xpath-header-enricher"}},[t("a",{staticClass:"header-anchor",attrs:{href:"#xpath-header-enricher"}},[e._v("#")]),e._v(" XPath Header Enricher")]),e._v(" "),t("p",[e._v("XPath Header Enricher 定义了 Header Enricher 消息转换器，该消息转换器根据消息有效负载计算 XPath 表达式，并将计算结果插入到消息头中。")]),e._v(" "),t("p",[e._v("下面的清单显示了所有可用的配置参数：")]),e._v(" "),t("div",{staticClass:"language- extra-class"},[t("pre",{pre:!0,attrs:{class:"language-text"}},[t("code",[e._v('<int-xml:xpath-header-enricher default-overwrite="true"    (1)\n                               id=""                       (2)\n                               input-channel=""            (3)\n                               output-channel=""           (4)\n                               should-skip-nulls="true">   (5)\n    <int:poller></int:poller>                              (6)\n    <int-xml:header name=""                                (7)\n                    evaluation-type="STRING_RESULT"        (8)\n                    header-type="int"                      (9)\n                    overwrite="true"                       (10)\n                    xpath-expression=""                    (11)\n                    xpath-expression-ref=""/>              (12)\n</int-xml:xpath-header-enricher>\n')])])]),t("table",[t("thead",[t("tr",[t("th",[t("strong",[e._v("1")])]),e._v(" "),t("th",[e._v("指定是否覆盖现有标头值的默认布尔值。"),t("br"),e._v("这仅对不提供自己的“覆盖”属性的子元素有效，"),t("br"),e._v("如果不设置“默认-覆盖”属性，指定的标头值不会覆盖任何具有相同标头名的现有标头值。"),t("br"),e._v("可选。")])])]),e._v(" "),t("tbody",[t("tr",[t("td",[t("strong",[e._v("2")])]),e._v(" "),t("td",[e._v("ID 为底层的 Bean 定义。"),t("br"),e._v("可选的。")])]),e._v(" "),t("tr",[t("td",[t("strong",[e._v("3")])]),e._v(" "),t("td",[e._v("这个端点的接收消息通道。"),t("br"),e._v("可选的。")])]),e._v(" "),t("tr",[t("td",[t("strong",[e._v("4")])]),e._v(" "),t("td",[e._v("丰富的消息被发送到的通道。"),t("br"),e._v("可选。")])]),e._v(" "),t("tr",[t("td",[t("strong",[e._v("5")])]),e._v(" "),t("td",[e._v("指定是否应跳过空值，例如可能从表达式求值返回的空值。"),t("br"),e._v("默认值是"),t("code",[e._v("true")]),e._v("。"),t("br"),e._v("如果空值应触发删除相应的标头，请将其设置为"),t("code",[e._v("false")]),e._v("。"),t("br"),e._v("可选。")])]),e._v(" "),t("tr",[t("td",[t("strong",[e._v("6")])]),e._v(" "),t("td",[e._v("与标题 Enricher 一起使用的 Poller。"),t("br"),e._v("可选的。")])]),e._v(" "),t("tr",[t("td",[t("strong",[e._v("7")])]),e._v(" "),t("td",[e._v("要丰富的标题的名称。"),t("br"),e._v("强制。")])]),e._v(" "),t("tr",[t("td",[t("strong",[e._v("8")])]),e._v(" "),t("td",[e._v("如果你没有设置"),t("code",[e._v("header-type")]),e._v("属性，则这是该标头值的类型。"),t("br"),e._v("允许以下值："),t("code",[e._v("BOOLEAN_RESULT")]),e._v("，"),t("code",[e._v("STRING_RESULT")]),e._v("，"),t("code",[e._v("NUMBER_RESULT")]),e._v("，"),t("code",[e._v("NODE_RESULT")]),e._v("，以及"),t("code",[e._v("NODE_LIST_RESULT")]),e._v("。"),t("br"),e._v("如果未设置，它在内部默认为"),t("code",[e._v("XPathEvaluationType.STRING_RESULT")]),e._v("。"),t("br"),e._v("可选。")])]),e._v(" "),t("tr",[t("td",[t("strong",[e._v("9")])]),e._v(" "),t("td",[e._v("标头值类型的完全限定类名称。"),t("br"),e._v("XPath 求值的结果通过"),t("code",[e._v("ConversionService")]),e._v("转换为该类型。"),t("br"),e._v("例如，这允许，将"),t("code",[e._v("NUMBER_RESULT")]),e._v("（一个 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使用 XPath 过滤器")]),e._v(" "),t("p",[e._v("这个组件定义了一个基于 XPath 的消息过滤器。在内部，这个组件使用"),t("code",[e._v("MessageFilter")]),e._v("来包装"),t("code",[e._v("AbstractXPathMessageSelector")]),e._v("的实例。")]),e._v(" "),t("table",[t("thead",[t("tr",[t("th"),e._v(" "),t("th",[e._v("有关更多详细信息，请参见"),t("RouterLink",{attrs:{to:"/spring-integration/filter.html#filter"}},[e._v("Filter")]),e._v("。")],1)])]),e._v(" "),t("tbody")]),e._v(" "),t("p",[e._v("要使用 XPath 过滤器，你至少必须通过声明"),t("code",[e._v("xpath-expression")]),e._v("元素或在"),t("code",[e._v("xpath-expression-ref")]),e._v("属性中引用一个 XPath 表达式来提供一个 XPath 表达式。")]),e._v(" "),t("p",[e._v("如果提供的 XPath 表达式计算为"),t("code",[e._v("boolean")]),e._v("值，则不需要进一步的配置参数。但是，如果 XPath 表达式的求值为"),t("code",[e._v("String")]),e._v("，则应该设置"),t("code",[e._v("match-value")]),e._v("属性，并与求值结果进行匹配。")]),e._v(" "),t("p",[t("code",[e._v("match-type")]),e._v("有三种选择：")]),e._v(" "),t("ul",[t("li",[t("p",[t("code",[e._v("exact")]),e._v(":在"),t("code",[e._v("java.lang.String")]),e._v("上对应于"),t("code",[e._v("equals")]),e._v("。底层实现使用"),t("code",[e._v("StringValueTestXPathMessageSelector")])])]),e._v(" "),t("li",[t("p",[t("code",[e._v("case-insensitive")]),e._v(":在"),t("code",[e._v("java.lang.String")]),e._v("上对应于"),t("code",[e._v("equals-ignore-case")]),e._v("。底层实现使用"),t("code",[e._v("StringValueTestXPathMessageSelector")])])]),e._v(" "),t("li",[t("p",[t("code",[e._v("regex")]),e._v(":匹配操作 1"),t("code",[e._v("java.lang.String")]),e._v("。底层实现使用"),t("code",[e._v("RegexTestXPathMessageSelector")])])])]),e._v(" "),t("p",[e._v("当提供“regex”的“match-type”值时，带有"),t("code",[e._v("match-value")]),e._v("属性的值必须是有效的正则表达式。")]),e._v(" "),t("p",[e._v("下面的示例显示了"),t("code",[e._v("xpath-filter")]),e._v("元素的所有可用属性：")]),e._v(" "),t("div",{staticClass:"language- extra-class"},[t("pre",{pre:!0,attrs:{class:"language-text"}},[t("code",[e._v('<int-xml:xpath-filter discard-channel=""                      (1)\n                      id=""                                   (2)\n                      input-channel=""                        (3)\n                      match-type="exact"                      (4)\n                      match-value=""                          (5)\n                      output-channel=""                       (6)\n                      throw-exception-on-rejection="false"    (7)\n                      xpath-expression-ref="">                (8)\n    <int-xml:xpath-expression ... />                          (9)\n    <int:poller ... />                                        (10)\n</int-xml:xpath-filter>\n')])])]),t("table",[t("thead",[t("tr",[t("th",[t("strong",[e._v("1")])]),e._v(" "),t("th",[e._v("要发送被拒绝的消息的消息通道。"),t("br"),e._v("可选的。")])])]),e._v(" "),t("tbody",[t("tr",[t("td",[t("strong",[e._v("2")])]),e._v(" "),t("td",[e._v("ID 为底层的 Bean 定义。"),t("br"),e._v("可选的。")])]),e._v(" "),t("tr",[t("td",[t("strong",[e._v("3")])]),e._v(" "),t("td",[e._v("这个端点的接收消息通道。"),t("br"),e._v("可选。")])]),e._v(" "),t("tr",[t("td",[t("strong",[e._v("4")])]),e._v(" "),t("td",[e._v("要在 XPath 求值结果和"),t("code",[e._v("match-value")]),e._v("之间应用匹配的类型。"),t("br"),e._v("默认值是"),t("code",[e._v("exact")]),e._v("。"),t("br"),e._v("可选的。")])]),e._v(" "),t("tr",[t("td",[t("strong",[e._v("5")])]),e._v(" "),t("td",[e._v("要与 XPath 求值结果匹配的字符串值。"),t("br"),e._v("如果不设置此属性，则 XPath 求值必须产生一个布尔结果。"),t("br"),e._v("可选。")])]),e._v(" "),t("tr",[t("td",[t("strong",[e._v("6")])]),e._v(" "),t("td",[e._v("将与筛选条件匹配的消息发送到的通道。"),t("br"),e._v("可选。")])]),e._v(" "),t("tr",[t("td",[t("strong",[e._v("7")])]),e._v(" "),t("td",[e._v("默认情况下，此属性被设置为"),t("code",[e._v("false")]),e._v("，并且被拒绝的消息（与筛选条件不匹配的消息）将被静默删除。"),t("br"),e._v("但是，如果设置为"),t("code",[e._v("true")]),e._v("，则消息拒绝将导致一个错误条件，并且异常将向上传播到调用者。"),t("br"),e._v("可选。")])]),e._v(" "),t("tr",[t("td",[t("strong",[e._v("8")])]),e._v(" "),t("td",[e._v("引用 XPath 表达式实例进行求值。")])]),e._v(" "),t("tr",[t("td",[t("strong",[e._v("9")])]),e._v(" "),t("td",[e._v("此子元素设置要求值的 XPath 表达式。"),t("br"),e._v("如果不包含此元素，则必须设置"),t("code",[e._v("xpath-expression-ref")]),e._v("属性。"),t("br"),e._v("此外，你只能包含一个"),t("code",[e._v("xpath-expression")]),e._v("元素。")])]),e._v(" "),t("tr",[t("td",[t("strong",[e._v("10")])]),e._v(" "),t("td",[e._v("与 XPath 过滤器一起使用的 Poller。"),t("br"),e._v("可选的。")])])])]),e._v(" "),t("h3",{attrs:{id:"xpath-spel-函数"}},[t("a",{staticClass:"header-anchor",attrs:{href:"#xpath-spel-函数"}},[e._v("#")]),e._v(" #XPath spel 函数")]),e._v(" "),t("p",[e._v("Spring 集成，自版本 3.0 以来，提供了内置的"),t("code",[e._v("#xpath")]),e._v("spel 函数，它调用"),t("code",[e._v("XPathUtils.evaluate(…​)")]),e._v("静态方法。此方法将委托给"),t("code",[e._v("org.springframework.xml.xpath.XPathExpression")]),e._v("。下面的清单展示了一些使用示例：")]),e._v(" "),t("div",{staticClass:"language- extra-class"},[t("pre",{pre:!0,attrs:{class:"language-text"}},[t("code",[e._v('<transformer expression="#xpath(payload, \'/name\')"/>\n\n<filter expression="#xpath(payload, headers.xpath, \'boolean\')"/>\n\n<splitter expression="#xpath(payload, \'//book\', \'document_list\')"/>\n\n<router expression="#xpath(payload, \'/person/@age\', \'number\')">\n    <mapping channel="output1" value="16"/>\n    <mapping channel="output2" value="45"/>\n</router>\n')])])]),t("p",[t("code",[e._v("#xpath()")]),e._v("还支持用于转换 XPath 求值结果的第三个可选参数。它可以是字符串常量之一（"),t("code",[e._v("string")]),e._v("，"),t("code",[e._v("boolean")]),e._v("，"),t("code",[e._v("number")]),e._v("，"),t("code",[e._v("node")]),e._v("，"),t("code",[e._v("node_list")]),e._v("和"),t("code",[e._v("document_list")]),e._v("）或"),t("code",[e._v("org.springframework.xml.xpath.NodeMapper")]),e._v("实例。默认情况下，"),t("code",[e._v("#xpath")]),e._v("spel 函数返回 XPath 求值的"),t("code",[e._v("String")]),e._v("表示。")]),e._v(" "),t("table",[t("thead",[t("tr",[t("th"),e._v(" "),t("th",[e._v("要启用"),t("code",[e._v("#xpath")]),e._v("spel 函数，你可以将"),t("code",[e._v("spring-integration-xml.jar")]),e._v("添加到 Classpath。"),t("br"),e._v("你不需要从 Spring 集成 XML 命名空间中声明任何组件。")])])]),e._v(" "),t("tbody")]),e._v(" "),t("p",[e._v("有关更多信息，请参见“`"),t("RouterLink",{attrs:{to:"/spring-integration/spel.html#spel"}},[e._v("Spring Expression Language (SpEL)")]),e._v("。")],1),e._v(" "),t("h3",{attrs:{id:"xml-验证过滤器"}},[t("a",{staticClass:"header-anchor",attrs:{href:"#xml-验证过滤器"}},[e._v("#")]),e._v(" XML 验证过滤器")]),e._v(" "),t("p",[e._v("XML 验证过滤器允许你根据提供的模式实例验证传入消息。支持以下模式类型：")]),e._v(" "),t("ul",[t("li",[t("p",[e._v("xml-schema（"),t("a",{attrs:{href:"https://www.w3.org/2001/XMLSchema",target:"_blank",rel:"noopener noreferrer"}},[e._v("https://www.w3.org/2001/XMLSchema"),t("OutboundLink")],1),e._v("）")])]),e._v(" "),t("li",[t("p",[e._v("relax-ng（"),t("a",{attrs:{href:"https://relaxng.org",target:"_blank",rel:"noopener noreferrer"}},[e._v("https://relaxng.org"),t("OutboundLink")],1),e._v("）")])])]),e._v(" "),t("p",[e._v("验证失败的消息可以被静默删除，也可以转发到可定义的"),t("code",[e._v("discard-channel")]),e._v("。此外，你可以将此筛选器配置为在验证失败的情况下抛出"),t("code",[e._v("Exception")]),e._v("。")]),e._v(" "),t("p",[e._v("下面的清单显示了所有可用的配置参数：")]),e._v(" "),t("div",{staticClass:"language- extra-class"},[t("pre",{pre:!0,attrs:{class:"language-text"}},[t("code",[e._v('<int-xml:validating-filter discard-channel=""                    (1)\n                           id=""                                 (2)\n                           input-channel=""                      (3)\n                           output-channel=""                     (4)\n                           schema-location=""                    (5)\n                           schema-type="xml-schema"              (6)\n                           throw-exception-on-rejection="false"  (7)\n                           xml-converter=""                      (8)\n                           xml-validator="">                     (9)\n    <int:poller .../>                                            (10)\n</int-xml:validating-filter>\n')])])]),t("table",[t("thead",[t("tr",[t("th",[t("strong",[e._v("1")])]),e._v(" "),t("th",[e._v("要发送被拒绝的消息的消息通道。"),t("br"),e._v("可选的。")])])]),e._v(" "),t("tbody",[t("tr",[t("td",[t("strong",[e._v("2")])]),e._v(" "),t("td",[e._v("ID 为底层的 Bean 定义。"),t("br"),e._v("可选的。")])]),e._v(" "),t("tr",[t("td",[t("strong",[e._v("3")])]),e._v(" "),t("td",[e._v("这个端点的接收消息通道。"),t("br"),e._v("可选的。")])]),e._v(" "),t("tr",[t("td",[t("strong",[e._v("4")])]),e._v(" "),t("td",[e._v("要发送已接受的消息的消息通道。"),t("br"),e._v("可选的。")])]),e._v(" "),t("tr",[t("td",[t("strong",[e._v("5")])]),e._v(" "),t("td",[e._v("设置模式的位置以验证消息的有效负载。"),t("br"),e._v("内部使用"),t("code",[e._v("org.springframework.core.io.Resource")]),e._v("接口。"),t("br"),e._v("你可以设置此属性或"),t("code",[e._v("xml-validator")]),e._v("属性，但不能同时设置这两个属性。"),t("br"),e._v("可选。")])]),e._v(" "),t("tr",[t("td",[t("strong",[e._v("6")])]),e._v(" "),t("td",[e._v("设置模式类型。"),t("br"),e._v("可以是"),t("code",[e._v("xml-schema")]),e._v("或"),t("code",[e._v("relax-ng")]),e._v("。"),t("br"),e._v("可选的。"),t("br"),e._v("如果未设置，它默认为"),t("code",[e._v("xml-schema")]),e._v("，在内部翻译为"),t("code",[e._v("org.springframework.xml.validation.XmlValidatorFactory#SCHEMA_W3C_XML")]),e._v("。")])]),e._v(" "),t("tr",[t("td",[t("strong",[e._v("7")])]),e._v(" "),t("td",[e._v("如果"),t("code",[e._v("true")]),e._v("，如果对所提供的消息的有效负载的验证失败，则抛出一个"),t("code",[e._v("MessageRejectedException")]),e._v("。"),t("br"),e._v("如果未设置，则默认为"),t("code",[e._v("false")]),e._v("。"),t("br"),e._v("可选。")])]),e._v(" "),t("tr",[t("td",[t("strong",[e._v("8")])]),e._v(" "),t("td",[e._v("参考自定义"),t("code",[e._v("org.springframework.integration.xml.XmlPayloadConverter")]),e._v("策略。"),t("br"),e._v("可选策略。")])]),e._v(" "),t("tr",[t("td",[t("strong",[e._v("9")])]),e._v(" "),t("td",[e._v("引用自定义的"),t("code",[e._v("sorg.springframework.xml.validation.XmlValidator")]),e._v("策略。"),t("br"),e._v("可以设置此属性或"),t("code",[e._v("schema-location")]),e._v("属性，但不能同时设置这两个属性。"),t("br"),e._v("可选。")])]),e._v(" "),t("tr",[t("td",[t("strong",[e._v("10")])]),e._v(" "),t("td",[e._v("与 XPath 过滤器一起使用的 Poller。"),t("br"),e._v("可选的。")])])])])])}),[],!1,null,null,null);r.default=n.exports}}]);