如何使用java验证XML?

时间:2011-02-28 10:13:57

标签: java xml

我需要解析一堆传入的XML文档,但它不包含DOCTYPE(它们都有不同的DTD)。 DTD由我自己创建。如何根据本地存储为文件的DTD验证XML文件?我有以下要求:

  1. 所有DTD(针对不同的XML)一旦进入XML,就会被加载到内存中,而不会查看本地存储的区域。
  2. 根据加载DTD文件验证传入的XML。
  3. 由于

1 个答案:

答案 0 :(得分:1)

您需要在SAX解析器上使用本地实体解析器,以下是如何实现它的示例:

class LocalEntityResolver implements EntityResolver {

private static final Logger LOG = ESAPI.getLogger(LocalEntityResolver.class);
private static final Map<String, String> DTDS;
static {
    DTDS = new HashMap<String, String>();
    DTDS.put("-//W3C//DTD XHTML 1.0 Transitional//EN",
            "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd");
    DTDS.put("-//W3C//ENTITIES Latin 1 for XHTML//EN",
            "http://www.w3.org/TR/xhtml1/DTD/xhtml-lat1.ent");
    DTDS.put("-//W3C//ENTITIES Symbols for XHTML//EN",
            "http://www.w3.org/TR/xhtml1/DTD/xhtml-symbol.ent");
    DTDS.put("-//W3C//ENTITIES Special for XHTML//EN",
            "http://www.w3.org/TR/xhtml1/DTD/xhtml-special.ent");
}

@Override
public InputSource resolveEntity(String publicId, String systemId)
        throws SAXException, IOException {
    InputSource input_source = null;
    if (publicId != null && DTDS.containsKey(publicId)) {
        LOG.debug(Logger.EVENT_SUCCESS, "Looking for local copy of [" + publicId + "]");

        final String dtd_system_id = DTDS.get(publicId);
        final String file_name = dtd_system_id.substring(
                dtd_system_id.lastIndexOf('/') + 1, dtd_system_id.length());

        InputStream input_stream = FileUtil.readStreamFromClasspath(
                file_name, "your/dtd/location",
                getClass().getClassLoader());
        if (input_stream != null) {
            LOG.debug(Logger.EVENT_SUCCESS, "Found local file [" + file_name + "]!");
            input_source = new InputSource(input_stream);
        }
    }

    return input_source;
}
}