如果您的问题不仅仅是 为什么？ 以及我该如何做到这一点......那么以下可能是您可能喜欢的替代方案。
我发现我无法让常规的 xerces 与 Android 一起使用，但我确实找到了 Xerces-for-Android，我可以使用它。以下是设置的详细信息和一些示例代码。祝你好运:)
以下内容对我有用：
- 创建验证实用程序。
- 将 xml 和 xsd 都放入 android 操作系统上的文件中，然后使用验证实用程序对其进行验证。
- 使用 Xerces-For-Android 进行验证。
Android 确实支持一些我们可以使用的包，我创建了我的 xml 验证实用程序，基于：http://docs.oracle.com/javase/1.5.0/docs/api/javax/xml/validation/package-summary.html
我最初的沙盒测试使用 java 非常顺利，然后我尝试将其移植到 Dalvik 并发现我的代码不起作用。 Dalvik 不支持某些东西，所以我做了一些修改。
我找到了对 android 的 xerces 的引用，所以我修改了我的沙盒测试（以下不适用于 android，之后的示例可以）：
import java.io.File;
import javax.xml.XMLConstants;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.transform.Source;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamSource;
import javax.xml.validation.Schema;
import javax.xml.validation.SchemaFactory;
import javax.xml.validation.Validator;
import org.w3c.dom.Document;
/**
* A Utility to help with xml communication validation.
*/
public class XmlUtil {
/**
* Validation method.
* Base code/example from: http://docs.oracle.com/javase/1.5.0/docs/api/javax/xml/validation/package-summary.html
*
* @param xmlFilePath The xml file we are trying to validate.
* @param xmlSchemaFilePath The schema file we are using for the validation. This method assumes the schema file is valid.
* @return True if valid, false if not valid or bad parse.
*/
public static boolean validate(String xmlFilePath, String xmlSchemaFilePath) {
// parse an XML document into a DOM tree
DocumentBuilder parser = null;
Document document;
// Try the validation, we assume that if there are any issues with the validation
// process that the input is invalid.
try {
// validate the DOM tree
parser = DocumentBuilderFactory.newInstance().newDocumentBuilder();
document = parser.parse(new File(xmlFilePath));
// create a SchemaFactory capable of understanding WXS schemas
SchemaFactory factory = SchemaFactory.newInstance(XMLConstants.W3C_XML_SCHEMA_NS_URI);
// load a WXS schema, represented by a Schema instance
Source schemaFile = new StreamSource(new File(xmlSchemaFilePath));
Schema schema = factory.newSchema(schemaFile);
// create a Validator instance, which can be used to validate an instance document
Validator validator = schema.newValidator();
validator.validate(new DOMSource(document));
} catch (Exception e) {
// Catches: SAXException, ParserConfigurationException, and IOException.
return false;
}
return true;
}
}
上面的代码必须进行一些修改才能与 xerces for android (http://gc.codehum.com/p/xerces-for-android/) 一起使用。获取项目需要SVN，以下是一些crib note：
download xerces-for-android
download silk svn (for windows users) from http://www.sliksvn.com/en/download
install silk svn (I did complete install)
Once the install is complete, you should have svn in your system path.
Test by typing "svn" from the command line.
I went to my desktop then downloaded the xerces project by:
svn checkout http://xerces-for-android.googlecode.com/svn/trunk/ xerces-for-android-read-only
You should then have a new folder on your desktop called xerces-for-android-read-only
使用上面的jar（最终我会把它做成一个jar，直接复制到我的源代码中以便快速测试。如果你想这样做，你可以用Ant快速制作jar（http://ant.apache.org/manual/using.html） )，我能够获得以下内容来进行我的 xml 验证：
import java.io.File;
import java.io.IOException;
import mf.javax.xml.transform.Source;
import mf.javax.xml.transform.stream.StreamSource;
import mf.javax.xml.validation.Schema;
import mf.javax.xml.validation.SchemaFactory;
import mf.javax.xml.validation.Validator;
import mf.org.apache.xerces.jaxp.validation.XMLSchemaFactory;
import org.xml.sax.SAXException;
/**
* A Utility to help with xml communication validation.
*/public class XmlUtil {
/**
* Validation method.
*
* @param xmlFilePath The xml file we are trying to validate.
* @param xmlSchemaFilePath The schema file we are using for the validation. This method assumes the schema file is valid.
* @return True if valid, false if not valid or bad parse or exception/error during parse.
*/
public static boolean validate(String xmlFilePath, String xmlSchemaFilePath) {
// Try the validation, we assume that if there are any issues with the validation
// process that the input is invalid.
try {
SchemaFactory factory = new XMLSchemaFactory();
Source schemaFile = new StreamSource(new File(xmlSchemaFilePath));
Source xmlSource = new StreamSource(new File(xmlFilePath));
Schema schema = factory.newSchema(schemaFile);
Validator validator = schema.newValidator();
validator.validate(xmlSource);
} catch (SAXException e) {
return false;
} catch (IOException e) {
return false;
} catch (Exception e) {
// Catches everything beyond: SAXException, and IOException.
e.printStackTrace();
return false;
} catch (Error e) {
// Needed this for debugging when I was having issues with my 1st set of code.
e.printStackTrace();
return false;
}
return true;
}
}
一些旁注：
为了创建文件，我制作了一个简单的文件实用程序来将字符串写入文件：
public static void createFileFromString(String fileText, String fileName) {
try {
File file = new File(fileName);
BufferedWriter output = new BufferedWriter(new FileWriter(file));
output.write(fileText);
output.close();
} catch ( IOException e ) {
e.printStackTrace();
}
}
我还需要写一个我可以访问的区域，所以我使用了：
String path = this.getActivity().getPackageManager().getPackageInfo(getPackageName(), 0).applicationInfo.dataDir;
有点hackish，它有效。我确信有一种更简洁的方法可以做到这一点，但是我想我会分享我的成功，因为我没有找到任何好的例子。