如何使用 JDOM2 使用 CDATA 转换 XML 文档?

How to transform XML document with CDATA using JDOM2?

源文件:

<content><![CDATA[>&< test]]></content>

XSLT 文档 (cdata-transformation.xslt):

<?xml version="1.0" encoding="utf-8"?>
<xsl:stylesheet version="1.1" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
  <xsl:output method="xml" cdata-section-elements="transformed" />

  <xsl:template match="/content">
    <transformed>
      <xsl:value-of select="." />
    </transformed>
  </xsl:template>
</xsl:stylesheet>

想要的结果:

<?xml version="1.0" encoding="UTF-8"?>
<transformed><![CDATA[>&< test]]></transformed>

实际结果:

<?xml version="1.0" encoding="UTF-8"?>
<transformed>&gt;&amp;&lt; test</transformed>

用于使用 JDOM2 进行测试的代码:

import java.io.IOException;
import java.io.InputStream;

import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerException;
import javax.xml.transform.TransformerFactory;

import org.jdom2.CDATA;
import org.jdom2.Document;
import org.jdom2.Element;
import org.jdom2.JDOMException;
import org.jdom2.input.SAXBuilder;
import org.jdom2.output.XMLOutputter;
import org.jdom2.transform.JDOMResult;
import org.jdom2.transform.JDOMSource;
import org.junit.Test;

public class CdataTransformationTest {

    @Test
    public void learning_cdataTransformationWithJdom() throws Exception {
        Document xslt = loadResource("xslt/cdata-transformation.xslt");
        Document source = new Document(new Element("content")
                .addContent(new CDATA(">&< test")));

        Document transformed = transform(source, xslt);

        XMLOutputter outputter = new XMLOutputter();
        System.out.println(outputter.outputString(transformed));
    }

    private static Document transform(Document sourceDoc, Document xsltDoc) throws TransformerException {
        JDOMSource source = new JDOMSource(sourceDoc);
        JDOMResult result = new JDOMResult();

        Transformer transformer = TransformerFactory.newInstance()
                .newTransformer(new JDOMSource(xsltDoc));

        transformer.transform(source, result);

        return result.getDocument();
    }

    private static Document loadResource(String resource) throws IOException, JDOMException {
        ClassLoader classloader = Thread.currentThread().getContextClassLoader();
        InputStream inputStream = classloader.getResourceAsStream(resource);
        if (inputStream != null) {
            try {
                SAXBuilder builder = new SAXBuilder();
                return builder.build(inputStream);
            } finally {
                inputStream.close();
            }
        } else {
            return null;
        }
    }
}

使用的 JDOM 版本:

<dependency>
    <groupId>org.jdom</groupId>
    <artifactId>jdom2</artifactId>
    <version>2.0.6</version>
</dependency>

使用的 XSLT 处理器:

<dependency>
    <groupId>xalan</groupId>
    <artifactId>xalan</artifactId>
    <version>2.7.1</version>
</dependency>

我四处寻找执行此操作的方法,最好的答案是在 CDATA 中包装内容所需的是在 cdata-section-elements 属性中添加标签名称。我无法让它与 JDOM 一起使用,也无法在使用 Free online XSL Transformer 时使用。我也尝试过使用 saxon 而不是 xalan,但结果相同。

为什么这行不通?我 missing/doing 哪里错了? JDOM 是否忽略了 cdata-section-elements 属性?

我也试过这样包装内容:

<xsl:text disable-output-escaping="yes">&lt;![CDATA[</xsl:text>
<xsl:value-of select="." />
<xsl:text disable-output-escaping="yes">]]&gt;</xsl:text>

但这会在 JDOM 中产生不需要的结果,使其难以使用。设置 outputer.getFormat().setIgnoreTrAXEscapingPIs(true); 时可见,使用漂亮格式时看起来真的很难看。

<?xml version="1.0" encoding="UTF-8"?>
<transformed>
  <?javax.xml.transform.disable-output-escaping?>
  &lt;![CDATA[
  <?javax.xml.transform.enable-output-escaping?>
  &gt;&amp;&lt; test
  <?javax.xml.transform.disable-output-escaping?>
  ]]&gt;
  <?javax.xml.transform.enable-output-escaping?>
</transformed>

您正在转换为 JDOMResult,即树表示,而不是流或文件。像 cdata-section-elements 这样的输出指令仅在 XSLT 处理器将结果序列化为流或文件时使用,而不是在内存中构建结果树时使用。所以我认为如果你想构建 CDATA 部分作为 XSLT 的结果 cdata-section-elements,你需要确保你写入文件或流或至少一个 StringWriter,然后你可以从该文件加载 JDOM 结果或流分别创建String.

将转换方法重写为:

private static Document transform(Document sourceDoc, Document xsltDoc) throws JDOMException, IOException, TransformerException {
    StringWriter writer = new StringWriter();
    JDOMSource source = new JDOMSource(sourceDoc);
    Result result = new StreamResult(writer);

    Transformer transformer = TransformerFactory.newInstance()
            .newTransformer(new JDOMSource(xsltDoc));

    transformer.transform(source, result);

    SAXBuilder builder = new SAXBuilder();
    return builder.build(new StringReader(writer.toString()));
}