Java-Android,org.w3c.dom：没有可用的验证DocumentBuilder实现

我正在尝试在Android 2.3.3上解析XML文档,但似乎没有验证解析器.我需要进行验证的原因是忽略XML文件中的空格(空白,回车,换行等).

那就是我想解析文档的方式：

DocumentBuilderFactory dbfac = DocumentBuilderFactory.newInstance();
dbfac.setValidating(true);
dbfac.setIgnoringElementContentWhitespace(true);
DocumentBuilder docBuilder;
docBuilder = dbfac.newDocumentBuilder();
Document d = docBuilder.parse(file);

file是文件位置的URL,为字符串.执行此代码的最后一行时,将引发以下异常：

javax.xml.parsers.ParserConfigurationException: No validating DocumentBuilder implementation available

当我取出dbfac.setValidating(true)时,没有异常发生,但是空白出现了问题.

有谁知道如何解决这个问题？我必须使用另一个解析器吗？

解决方法:

在Android上,当验证设置为true时,对实现进行硬编码以引发异常.这是Android source code link：

@Override
public DocumentBuilder newDocumentBuilder()
        throws ParserConfigurationException {
    if (isValidating()) {
        throw new ParserConfigurationException(
                "No validating DocumentBuilder implementation available");
    }

    /**
     * TODO If Android is going to support a different DocumentBuilder
     * implementations, this should be wired here. If we wanted to
     * allow different implementations, these could be distinguished by
     * a special feature (like http://www.org.apache.harmony.com/xml/expat)
     * or by throwing the full SPI monty at it.
     */
    DocumentBuilderImpl builder = new DocumentBuilderImpl();
    builder.setCoalescing(isCoalescing());
    builder.setIgnoreComments(isIgnoringComments());
    builder.setIgnoreElementContentWhitespace(isIgnoringElementContentWhitespace());
    builder.setNamespaceAware(isNamespaceAware());

    // TODO What about expandEntityReferences?

    return builder;
}

标签：dom,xml,java,android,xml-parsing
来源： https://codeday.me/bug/20191202/2085220.html