如何从 xsd 模式生成 xml?

本文介绍了如何从 xsd 模式生成 xml?的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！

问题描述

我有 xsd 架构..如何通过在 java.. 中以编程方式使用此架构生成 xml?它应该是动态的，这意味着我可以给出任何模式.有没有图书馆可以做同样的事情.?我已经看过其他帖子了，但不幸的是它不适合我..请给旅游建议......?我没有找到任何方法来做同样的事情.

I am having xsd schema..How can I generate the xml by using this schema programmatically in java..? and it should be dynamic ,means I can give any schema.Is there any library available to do same.? I have alrady seen the other post also,but unfortunately it did not suit me.. please give tour ideas....???I am not finding any approach to do same.

推荐答案

以下代码根据您的需要执行验证，并告诉您解析过程中发生错误的行号您将需要以下 jars 来运行此代码

The following code performs validation as per your need,and also tells you the line number where the error occurred during parsingYou will need following jars to run this code

唯一需要更改的代码是 validateSchema() 方法，其中请求响应参数需要替换为 xml 的字符串表示和 XSD 的字符串表示.

Only code change needed is at validateSchema() method where request response args need to be replaced with a string representation of your xml and String representation of your XSD.

resolver.jar、xml-apis.jar、serializer.jar、xercesImpl.jar

resolver.jar, xml-apis.jar, serializer.jar, xercesImpl.jar

import org.apache.xerces.parsers.SAXParser;
import org.apache.xerces.xni.Augmentations;
import org.apache.xerces.xni.NamespaceContext;
import org.apache.xerces.xni.XMLLocator;
import org.apache.xerces.xni.XNIException;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
import org.xml.sax.SAXParseException;
import org.xml.sax.helpers.DefaultHandler;

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

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 * Performs validation on XML based on the XSD. Overrides the
 * {@link SAXParser}.
 *
 *
 */
public class ValidateSchema extends SAXParser {

  /**
   * Container for current line and coloum number being parsed in the XML.
   */
  private XMLLocator locator;

  /**
   * Default public constructor.
   */
  public ValidateSchema() {
    super();
  }

  /**
   * Used for obtaining the {@link XMLLocator} locator object.
   */
  @Override
  public void startDocument(
      XMLLocator locator, String encoding, NamespaceContext namespaceContext, Augmentations augs)
      throws XNIException {
    this.locator = locator;
    super.startDocument(locator, encoding, namespaceContext, augs);
  }

  /**
   * Validates the XML against the provided XSD.
   *
   * @param req HttpServletRequest object.
   * @param resp HttpServletResponse object.
   * @throws IOException
   */
  public void validateSchema(HttpServletRequest req, HttpServletResponse resp)
      throws IOException {
    String content = req.getParameter("data");
    String selectbox = req.getParameter("selectbox");
    content = content.trim();

    // Convert the XML string to byte stream.
    InputStream is = new ByteArrayInputStream(content.getBytes());

    try {
      this.setFeature(Constants.VALIDATION_PROP, true);
      this.setFeature(Constants.SCHEMA_PROP, true);
      this.setFeature(Constants.DYNAMIC_PROP, true);
      this.setFeature(Constants.SCHEMA_CHECKING_PROP, true);
      if("1".equalsIgnoreCase(selectbox)) {
    this.setProperty(Constants.SCHEMA_LOC,"oem.xsd" );
      } else if("2".equalsIgnoreCase(selectbox)) {
    this.setProperty(Constants.SCHEMA_LOC,"carrier.xsd" );
      }

      Validator handler = new Validator();
      this.setErrorHandler(handler);

      InputSource isp = new InputSource();
      isp.setByteStream(is);
      isp.setEncoding("UTF-8");
      this.parse(isp);

      if (handler.validationError == true) {
    StringBuffer errorMessage = new StringBuffer(512);
    errorMessage
        .append("<div style='background: #ffebe6;border: 0px solid #ffe0d7;color:#c10000;height:60px;padding: 5px;'>")
        .append(Constants.INVALID_XML_DOCUMENT)
        .append(" LineNo: ")
        .append(handler.saxParseException.getLineNumber())
        .append(" ColumnNo: ")
        .append(handler.saxParseException.getColumnNumber())
        .append("<br/>")
        .append(handler.validationError)
        .append(handler.saxParseException.getMessage())
        .append("</div>");
    System.out.println( errorMessage );
      } else {
    StringBuffer validMsg = new StringBuffer(512);
    validMsg.append("<div style='background: #ebeff9;border: 0px solid #6b90da;height:60px;padding: 5px;'>")
    .append(Constants.VALID_XML_DOCUMENT).append("</div>");
    System.out.println( validMsg );
      }
    } catch (SAXException e) {
      StringBuffer errorMessage = new StringBuffer(512);
      errorMessage
      .append("<div style='background: #ffebe6;border: 0px solid #ffe0d7;color:#c10000;height:60px;padding: 5px;'>")
      .append(Constants.INVALID_XML_DOCUMENT)
      .append(" LineNo: ")
      .append(this.locator.getLineNumber())
      .append(" ColumnNo: ")
      .append(this.locator.getColumnNumber())
      .append(" <br/>")
      .append(e.getMessage())
      .append("</div>");
    System.out.println( errorMessage );
    } catch (Exception e) {
      StringBuffer errorMessage = new StringBuffer(512);
      errorMessage
      .append("<div style='background: #ffebe6;border: 1px solid #ffe0d7;color:#c10000;height:60px;padding: 5px;'>")
      .append(Constants.INVALID_XML_DOCUMENT)
      .append(" <br/>")
      .append(e.getMessage())
      .append("</div>");
     System.out.println( errorMessage );
    }
  }

  /**
   * Writes back the response to client.
   *
   * @param msg Response message.
   * @param resp HttpServletResponse object.
   * @throws IOException
   */
  private void responseWrite(
      String msg, HttpServletResponse resp) throws IOException {
    resp.setContentType("text/html");
    resp.getWriter().write(msg);
  }

  /**
   * Custom handler for Errors while parsing documents.
   */
  private class Validator extends DefaultHandler {
    public boolean validationError = false;
    public SAXParseException saxParseException = null;

    /**
     * @throws SAXException
     */
    @Override
    public void error(SAXParseException exception) throws SAXException {
      validationError = true;
      saxParseException = exception;
    }

    /**
     * @throws SAXException
     */
    @Override
    public void fatalError(SAXParseException exception) throws SAXException {
      validationError = true;
      saxParseException = exception;
    }

    /**
     * @throws SAXException
     */
    @Override
    public void warning(SAXParseException exception) throws SAXException {
    }
  }
}

Constants.Java 包含您需要指定的验证属性

public final class Constants {

public static final String VALIDATION_PROP = "http://xml.org/sax/features/validation";
public static final String SCHEMA_PROP = "http://apache.org/xml/features/validation/schema";
public static final String DYNAMIC_PROP = "http://apache.org/xml/features/validation/dynamic";
public static final String SCHEMA_CHECKING_PROP =
    "http://apache.org/xml/features/validation/schema-full-checking";
public static final String SCHEMA_LOC =
    "http://apache.org/xml/properties/schema/external-noNamespaceSchemaLocation";
public static final String VALID_XML_DOCUMENT = "The above XML is valid.";
public static final String INVALID_XML_DOCUMENT = "The Document has error at:";

}

这篇关于如何从 xsd 模式生成 xml?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！

JAR